Cytotoxicity evaluation of haloperidol, clozapine and a new molecule with antipsychotic potential, PT-31, in NIH-3T3 cells

Schizophrenia is an illness that affects 26 million people worldwide. However, conventional antipsychotics present side effects and toxicity, highlighting the need for new antipsychotics. We aimed to evaluate the cytotoxicity of haloperidol (HAL), clozapine (CLO), and a new molecule with antipsychotic potential, PT-31, in NIH-3T3 cells. The neutral red uptake assay and the MTT assay were performed to evaluate cell viability and mitochondrial activity, morphological changes were assessed, and intracellular reactive oxygen species (ROS) detection was performed. HAL and CLO (0.1 μM) showed a decrease in cell viability in the neutral red uptake assay and in the MTT assay. In addition, cell detachment, content decrease, rounding and cell death were also observed at 0.1 μM for both antipsychotics. An increase in ROS was observed for HAL (0.001, 0.01 and 1 μM) and CLO (0.01 and 1 μM). PT-31 did not alter cell viability in any of the assays, although it increased ROS at 0.01 and 1 μM. HAL and CLO present cytotoxicity at 0.1 μM, possibly through apoptosis and necrosis. In contrast, PT-31 does not present cytotoxicity to NIH-3T3 cells. Further studies must be performed for a better understanding of these mechanisms and the potential risk of conventional antipsychotics

Smoking fewer than 20 cigarettes per day and remaining abstinent for more than 12 hours reduces carboxyhemoglobin levels in packed red blood cells for transfusion

The prevalence of smokers among blood donors and the effect of smoking on the quality of donated blood have not been extensively explored. In the present study, we determined the prevalence of smoker donors in a large blood bank in Southern Brazil and evaluated the quality of packed red blood cells (RBCs) from these donors through recommended quality control tests and measurement of carboxyhemoglobin (COHb) levels. We then assessed the influence of smoking habits and abstinence before donation on these parameters. Material and methods An observational study was conducted to determine the prevalence of smoking donors, while a prospective cohort study compared conventional hematological and serological parameters and COHb levels at 0, 15, and 30 days after donation in RBCs donated by smokers (N = 31) and nonsmokers (N = 31) and their association with smoking habits and abstinence before donation. Results Of 14,428 blood donations received in 1 year, 5.9% were provided by smokers. Storage over time slightly altered some quality parameters, such as hematocrit, hemoglobin, hemolysis, and COHb levels, in RBC packs. COHb levels were higher in RBC packs from smokers (8%) than from non-smokers (2%), and increased as a function of the number of cigarettes smoked daily and time elapsed since the last cigarette smoked before donation. Lower levels were found in RBC packs from donors who smoked fewer than 20 cigarettes per day or remained abstinent for more than 12h before giving blood. Conclusion Although cigarette smoke had no significant effect on blood quality parameters such as hematocrit, hemoglobin, or hemolysis, it quadrupled COHb levels in packed RBCs. Abstinence from smoking for more than 12h or smoking fewer than 20 cigarettes daily helped decrease COHb levels. Implications Given the increasing prevalence of tobacco use worldwide, we suggest blood banks recommend 12h of tobacco abstinence before donation and analyze COHb levels in donated blood as an approach to reduce risk for high-risk recipients

Early detection of SARS-CoV-2 P.1 variant in Southern Brazil and reinfection of the same patient by P.2

Multiple variants of the Severe Acute Respiratory Syndrome coronavirus 2 virus (SARS-CoV-2) have been constantly reported across the world. The B.1.1.28 lineage has been evolving in Brazil since February 2020 and originated the P.1 variant of concern (VOC), recently named as the Gamma variant by the newly WHO nomenclature proposal, and P.2 as a variant of interest (VOI). Here we describe an early case of P.1 primary infection in Southern Brazil in late November 2020, soon after the emergence of the variant in Manaus, Northern Brazil. The same male patient was reinfected by another B.1.1.28 variant, namely P.2, in March, 2021. The genomic analysis confirmed genetically significant differences between the two viruses recovered in both infections, the P.1 lineage in the first episode and P.2 in the reinfection. Due the very early detection of P.1, we have also investigated the circulation of P.1 in the same region by differential RT-qPCR, showing that this was an isolated case of P.1 at the time of detection, and this variant has disseminated and became prominent from late January to the end of March, 2021. SARS-CoV-2 recent reports of reinfection have raised critical questions on whether and how well a first infection protects against reinfection

Genomic epidemiology of SARS-CoV-2 in Esteio, Rio Grande do Sul, Brazil

Background: Brazil is the third country most affected by Coronavirus disease-2019 (COVID-19), but viral evolution in municipality resolution is still poorly understood in Brazil and it is crucial to understand the epidemiology of viral spread. We aimed to track molecular evolution and spread of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Esteio (Southern Brazil) using phylogenetics and phylodynamics inferences from 21 new genomes in global and regional context. Importantly, the case fatality rate (CFR) in Esteio (3.26%) is slightly higher compared to the Rio Grande do Sul (RS) state (2.56%) and the entire Brazil (2.74%). Results: We provided a comprehensive view of mutations from a representative sampling from May to October 2020, highlighting two frequent mutations in spike glycoprotein (D614G and V1176F), an emergent mutation (E484K) in spike Receptor Binding Domain (RBD) characteristic of the B.1.351 and P.1 lineages, and the adjacent replacement of 2 amino acids in Nucleocapsid phosphoprotein (R203K and G204R). E484K was found in two genomes from mid-October, which is the earliest description of this mutation in Southern Brazil. Lineages containing this substitution must be subject of intense surveillance due to its association with immune evasion. We also found two epidemiologicallyrelated clusters, including one from patients of the same neighborhood. Phylogenetics and phylodynamics analysis demonstrates multiple introductions of the Brazilian most prevalent lineages (B.1.1.33 and B.1.1.248) and the establishment of Brazilian lineages ignited from the Southeast to other Brazilian regions. Conclusions: Our data show the value of correlating clinical, epidemiological and genomic information for the understanding of viral evolution and its spatial distribution over time. This is of paramount importance to better inform policy making strategies to fight COVID-19

Efeito da taurina sobre os sistemas gabaérgico e glutamatérgico e sobre parâmetros comportamentais de ratos cronicamente tratados e abstinentes ao álcool

A dependência ao álcool é um problema de saúde pública e está relacionada a milhares de mortes por ano. Indivíduos dependentes, quando em abstinência ao uso de álcool, apresentam sintomas negativos que contribuem para a recaída e a manutenção do ciclo da adição. Muitos dos sintomas da abstinência são resultantes do desequilíbrio entre os sistemas GABAérgico e glutamatérgico. A neuroplasticidade induzida pelo álcool afeta principalmente os receptores do ácido gama-aminobutírico A (GABAA) e os receptores N-metil-D-aspartato (NMDA) de glutamato. A taurina, um aminoácido sulfonado, atua como modulador inibitório e diminui a excitotoxicidade induzida por glutamato por interação com os receptores NMDA, diminuindo o influxo de cálcio na célula. Portanto, no primeiro artigo apresentado nesta tese foram avaliados os efeitos da taurina (100 mg/kg/dia) no comportamento de ratos cronicamente tratados (2 g/kg, 2x ao dia) ou após cinco dias de abstinência ao álcool. Também foi verificada a expressão de RNAm da subunidade α2 do receptor de GABAA e de BDNF no córtex frontal destes animais. Os resultados obtidos mostraram que mesmo após cinco dias de abstinência os ratos ainda apresentam diminuição no comportamento exploratório no campo aberto quando comparados ao grupo controle. O tratamento com taurina foi capaz de restaurar o comportamento dos animais abstinentes. A taurina reduziu a expressão de BDNF no grupo cronicamente tratado com álcool, demonstrando um efeito neuroprotetor e diminuiu a expressão de α2 apenas nos ratos controle. No segundo artigo avaliou-se a expressão de RNAm das subunidades α1, α4, δ e γ2 de GABAA e GluN2A e GluN2B de NMDA no hipocampo de ratos submetidos ao mesmo protocolo de exposição crônica e abstinência ao álcool. Não foram observadas diferenças significativas de expressão de subunidades entre os grupos estudados. Porém, análise de correlação mostrou que o uso crônico de álcool e a abstinência alteram as correlações entre as subunidades observadas no grupo controle, e a taurina não foi capaz de reverter este efeito. Apesar de sua interação com os receptores GABAA e NMDA a taurina não é eficaz para equilibrar estes dois sistemas que são afetados pelo uso crônico e abstinência ao álcool. Os resultados obtidos nesta tese contribuem para a elucidação das alterações decorrentes do uso e abstinência ao álcool e do tratamento com taurina sobre sistemas neurotransmissores e comportamentos. Tais resultados podem contribuir para o desenvolvimento de novos fármacos para o tratamento da dependência.Alcohol dependency is a public health problem and is related to millions of deaths per year. Alcohol dependent people presents negative symptoms during withdrawal and theses symptoms contribute to relapse and maintenance of addiction cycle. Many of the withdrawal symptoms are due to unbalance of GABAergic and glutamatergic systems. Neuroplasticity induced by alcohol mainly affects gamma-aminobutiric acid A (GABAA) and glutamate N-methil-D-aspartate (NMDA) receptors. Taurine, a sulfonated amino acid, acts as an inhibitory neurotransmitter and decreases glutamate induced excitotoxicity through direct interaction with NMDA receptors, decreasing cellular Ca2+ influx. Therefore, in the first presented article we evaluated taurine (100 mg/kg/day) in rats chronically treated (2 g/kg, twice a day) or alcohol five days withdrawal. GABAA α2 subunit receptor and BDNF mRNA expression was also verified in the frontal cortex of these animals. Results showed that even after five days of withdrawal, the rats still showed difference in exploratory behavior in the open field when compared to the control group. Taurine treatment restored this behavior in withdrawal animals. Taurine also reduced BDNF expression in the chronically alcohol-treated group, demonstrating a neuroprotective effect, and decreased α2 expression only in control rats. In the second article GABAA α1, α4, δ and γ2 subunits and NMDA GluN2A and GluN2B subunits were evaluated in the hippocampus of rats exposed to the same protocol of chronic alcohol and withdrawal. No significant differences in subunit expression were observed between studied groups. Correlation analysis showed that the chronic alcohol treatment and withdrawal alter the correlations between subunits observed in control group. Taurine was not able to reverse this effect. Besides taurine interaction with GABAA and NMDA receptors, it is not effective balancing these two systems that are affected by alcohol chronic use and withdrawal. Our results contribute to the elucidation of changes related to alcohol use and withdrawal and taurine effect in different brain areas. They may contributes to the development of new drugs for the treatment of addiction

Estudo da camada de óxido obtida por tratamento térmico do NiTi e do comportamento eletroquímico do NiTi em diferentes eletrólitos que simulam o fluído corpóreo

O NiTi é uma liga equiatômica de níquel-titânio amplamente utilizada como biomaterial devido às suas propriedades de memória de forma e superelasticidade. Vários estudos de tratamento superficial da liga NiTi têm sido desenvolvidos, visando melhorar a resistência à corrosão, e bloquear a saída do Ni para os tecidos adjacentes. O óxido de titânio (TiO2) pode ser formado na superfície do NiTi, durante o processo de tratamento térmico de memória de forma. A espessura da camada do óxido formado depende do tempo e da temperatura aplicada no tratamento térmico, e esta camada pode ser eficiente protegendo e melhorando a biocompatibilidade do material de base sem a utilização de outros tratamentos superficiais. Neste trabalho avaliou-se o efeito do tempo e da temperatura do tratamento térmico, no crescimento da camada de óxido, nas temperaturas utilizadas no processo de tratamento térmico para dar forma (530 e 570 °C) à liga de NiTi com memória de forma. Os resultados obtidos mostraram que é possível obter morfologias e características distintas para as camadas de TiO2, controlando os parâmetros tempo e temperatura, do processo de memória de forma. Outra questão importante na avaliação de superfícies para aplicação biomédica é a utilização de métodos e parâmetros adequados permitam a caracterização em condições que representem as situações mais próximas daquelas apresentadas pelo fluido corpóreo. No entanto, diferentes autores utilizam eletrólitos distintos para simular o fluído corpóreo em ensaios de caracterização eletroquímica, o que dificulta a correlação dos resultados encontrados nos artigos. No presente trabalho avaliou-se o comportamento eletroquímico de NiTi polido em diferentes soluções, utilizadas na literatura para simular o fluído corpóreo: solução de Hanks, solução de Hanks com sal balanceado (HBSS), solução salina de fluído corpóreo (SBF), solução de Ringer e solução de NaCl 0,9%. O comportamento eletroquímico do NiTi foi avaliado por ensaios de monitoramento do potencial de circuito aberto (OCP) e voltametria cíclica. Os resultados obtidos demonstraram que a liga de NiTi apresenta o mesmo mecanismo de corrosão (corrosão por pitting) em todas as soluções estudadas. No entanto, o potencial de corrosão desenvolvido em cada eletrólito foi diferente, sendo que a liga de NiTi apresentou comportamento mais ativo na solução HBSS.NiTi is an equiatomic nickel-titanium alloy widely used as biomaterials because of their shape memory and superelasticity properties. Several studies regarding superficial treatments of NiTi alloy have been developed, aiming to improve corrosion resistance, and to block Ni release to adjacent tissues. Titanium oxide (TiO2) can be formed on NiTi surface, during heat treatment of shape memory process. TiO2 is largely studied because its increase corrosion resistance of the alloy. Thickness of oxide layer depends on the temperature that is applied and on the duration of the heat treatment, and this TiO2 layer can be efficient in protecting and improving biocompatibility of the bulk metal without another superficial treatment. In this work it was evaluated the heat treatments duration effects in the oxide growth on the NiTi surface, at the main used temperatures used in the shape process (530 and 570 °C) of shape memory NiTi alloy. Obtained results showed it is possible to obtain distinct morphologies and characteristics of the TiO2 layer by controlling shape memory parameters, as time and temperature. Another important issue in evaluation of surfaces for biomedical application is the use of appropriated parameters and methods that allows the characterization under conditions that represent the environment more similar to body fluid. However, different authors employ distinct electrolytes in electrochemical characterization tests, which makes difficult the correlation between article results. In present work it was evaluated the electrochemical behavior of mechanically polished NiTi in different solutions, used to simulated the body fluid: Hank’s solution, Hank’s balanced salt solution (HBSS), saline body fluid solution (SBF), Ringer’s solution and 0.9% NaCl solution. Electrochemical behavior of NiTi was evaluated by open circuit potential (OCP) monitoring and cyclic voltammetry tests. Obtained results demonstrated that NiTi alloy presents the same corrosion mechanism (pitting corrosion) in all studied solutions. Although, corrosion potential obtained was different in each electrolyte, being the NiTi alloy presented most ative behavior in HBSS solution

Estudo da camada de óxido obtida por tratamento térmico do NiTi e do comportamento eletroquímico do NiTi em diferentes eletrólitos que simulam o fluído corpóreo

O NiTi é uma liga equiatômica de níquel-titânio amplamente utilizada como biomaterial devido às suas propriedades de memória de forma e superelasticidade. Vários estudos de tratamento superficial da liga NiTi têm sido desenvolvidos, visando melhorar a resistência à corrosão, e bloquear a saída do Ni para os tecidos adjacentes. O óxido de titânio (TiO2) pode ser formado na superfície do NiTi, durante o processo de tratamento térmico de memória de forma. A espessura da camada do óxido formado depende do tempo e da temperatura aplicada no tratamento térmico, e esta camada pode ser eficiente protegendo e melhorando a biocompatibilidade do material de base sem a utilização de outros tratamentos superficiais. Neste trabalho avaliou-se o efeito do tempo e da temperatura do tratamento térmico, no crescimento da camada de óxido, nas temperaturas utilizadas no processo de tratamento térmico para dar forma (530 e 570 °C) à liga de NiTi com memória de forma. Os resultados obtidos mostraram que é possível obter morfologias e características distintas para as camadas de TiO2, controlando os parâmetros tempo e temperatura, do processo de memória de forma. Outra questão importante na avaliação de superfícies para aplicação biomédica é a utilização de métodos e parâmetros adequados permitam a caracterização em condições que representem as situações mais próximas daquelas apresentadas pelo fluido corpóreo. No entanto, diferentes autores utilizam eletrólitos distintos para simular o fluído corpóreo em ensaios de caracterização eletroquímica, o que dificulta a correlação dos resultados encontrados nos artigos. No presente trabalho avaliou-se o comportamento eletroquímico de NiTi polido em diferentes soluções, utilizadas na literatura para simular o fluído corpóreo: solução de Hanks, solução de Hanks com sal balanceado (HBSS), solução salina de fluído corpóreo (SBF), solução de Ringer e solução de NaCl 0,9%. O comportamento eletroquímico do NiTi foi avaliado por ensaios de monitoramento do potencial de circuito aberto (OCP) e voltametria cíclica. Os resultados obtidos demonstraram que a liga de NiTi apresenta o mesmo mecanismo de corrosão (corrosão por pitting) em todas as soluções estudadas. No entanto, o potencial de corrosão desenvolvido em cada eletrólito foi diferente, sendo que a liga de NiTi apresentou comportamento mais ativo na solução HBSS.NiTi is an equiatomic nickel-titanium alloy widely used as biomaterials because of their shape memory and superelasticity properties. Several studies regarding superficial treatments of NiTi alloy have been developed, aiming to improve corrosion resistance, and to block Ni release to adjacent tissues. Titanium oxide (TiO2) can be formed on NiTi surface, during heat treatment of shape memory process. TiO2 is largely studied because its increase corrosion resistance of the alloy. Thickness of oxide layer depends on the temperature that is applied and on the duration of the heat treatment, and this TiO2 layer can be efficient in protecting and improving biocompatibility of the bulk metal without another superficial treatment. In this work it was evaluated the heat treatments duration effects in the oxide growth on the NiTi surface, at the main used temperatures used in the shape process (530 and 570 °C) of shape memory NiTi alloy. Obtained results showed it is possible to obtain distinct morphologies and characteristics of the TiO2 layer by controlling shape memory parameters, as time and temperature. Another important issue in evaluation of surfaces for biomedical application is the use of appropriated parameters and methods that allows the characterization under conditions that represent the environment more similar to body fluid. However, different authors employ distinct electrolytes in electrochemical characterization tests, which makes difficult the correlation between article results. In present work it was evaluated the electrochemical behavior of mechanically polished NiTi in different solutions, used to simulated the body fluid: Hank’s solution, Hank’s balanced salt solution (HBSS), saline body fluid solution (SBF), Ringer’s solution and 0.9% NaCl solution. Electrochemical behavior of NiTi was evaluated by open circuit potential (OCP) monitoring and cyclic voltammetry tests. Obtained results demonstrated that NiTi alloy presents the same corrosion mechanism (pitting corrosion) in all studied solutions. Although, corrosion potential obtained was different in each electrolyte, being the NiTi alloy presented most ative behavior in HBSS solution

Efeito da taurina sobre os sistemas gabaérgico e glutamatérgico e sobre parâmetros comportamentais de ratos cronicamente tratados e abstinentes ao álcool

A dependência ao álcool é um problema de saúde pública e está relacionada a milhares de mortes por ano. Indivíduos dependentes, quando em abstinência ao uso de álcool, apresentam sintomas negativos que contribuem para a recaída e a manutenção do ciclo da adição. Muitos dos sintomas da abstinência são resultantes do desequilíbrio entre os sistemas GABAérgico e glutamatérgico. A neuroplasticidade induzida pelo álcool afeta principalmente os receptores do ácido gama-aminobutírico A (GABAA) e os receptores N-metil-D-aspartato (NMDA) de glutamato. A taurina, um aminoácido sulfonado, atua como modulador inibitório e diminui a excitotoxicidade induzida por glutamato por interação com os receptores NMDA, diminuindo o influxo de cálcio na célula. Portanto, no primeiro artigo apresentado nesta tese foram avaliados os efeitos da taurina (100 mg/kg/dia) no comportamento de ratos cronicamente tratados (2 g/kg, 2x ao dia) ou após cinco dias de abstinência ao álcool. Também foi verificada a expressão de RNAm da subunidade α2 do receptor de GABAA e de BDNF no córtex frontal destes animais. Os resultados obtidos mostraram que mesmo após cinco dias de abstinência os ratos ainda apresentam diminuição no comportamento exploratório no campo aberto quando comparados ao grupo controle. O tratamento com taurina foi capaz de restaurar o comportamento dos animais abstinentes. A taurina reduziu a expressão de BDNF no grupo cronicamente tratado com álcool, demonstrando um efeito neuroprotetor e diminuiu a expressão de α2 apenas nos ratos controle. No segundo artigo avaliou-se a expressão de RNAm das subunidades α1, α4, δ e γ2 de GABAA e GluN2A e GluN2B de NMDA no hipocampo de ratos submetidos ao mesmo protocolo de exposição crônica e abstinência ao álcool. Não foram observadas diferenças significativas de expressão de subunidades entre os grupos estudados. Porém, análise de correlação mostrou que o uso crônico de álcool e a abstinência alteram as correlações entre as subunidades observadas no grupo controle, e a taurina não foi capaz de reverter este efeito. Apesar de sua interação com os receptores GABAA e NMDA a taurina não é eficaz para equilibrar estes dois sistemas que são afetados pelo uso crônico e abstinência ao álcool. Os resultados obtidos nesta tese contribuem para a elucidação das alterações decorrentes do uso e abstinência ao álcool e do tratamento com taurina sobre sistemas neurotransmissores e comportamentos. Tais resultados podem contribuir para o desenvolvimento de novos fármacos para o tratamento da dependência.Alcohol dependency is a public health problem and is related to millions of deaths per year. Alcohol dependent people presents negative symptoms during withdrawal and theses symptoms contribute to relapse and maintenance of addiction cycle. Many of the withdrawal symptoms are due to unbalance of GABAergic and glutamatergic systems. Neuroplasticity induced by alcohol mainly affects gamma-aminobutiric acid A (GABAA) and glutamate N-methil-D-aspartate (NMDA) receptors. Taurine, a sulfonated amino acid, acts as an inhibitory neurotransmitter and decreases glutamate induced excitotoxicity through direct interaction with NMDA receptors, decreasing cellular Ca2+ influx. Therefore, in the first presented article we evaluated taurine (100 mg/kg/day) in rats chronically treated (2 g/kg, twice a day) or alcohol five days withdrawal. GABAA α2 subunit receptor and BDNF mRNA expression was also verified in the frontal cortex of these animals. Results showed that even after five days of withdrawal, the rats still showed difference in exploratory behavior in the open field when compared to the control group. Taurine treatment restored this behavior in withdrawal animals. Taurine also reduced BDNF expression in the chronically alcohol-treated group, demonstrating a neuroprotective effect, and decreased α2 expression only in control rats. In the second article GABAA α1, α4, δ and γ2 subunits and NMDA GluN2A and GluN2B subunits were evaluated in the hippocampus of rats exposed to the same protocol of chronic alcohol and withdrawal. No significant differences in subunit expression were observed between studied groups. Correlation analysis showed that the chronic alcohol treatment and withdrawal alter the correlations between subunits observed in control group. Taurine was not able to reverse this effect. Besides taurine interaction with GABAA and NMDA receptors, it is not effective balancing these two systems that are affected by alcohol chronic use and withdrawal. Our results contribute to the elucidation of changes related to alcohol use and withdrawal and taurine effect in different brain areas. They may contributes to the development of new drugs for the treatment of addiction