Advancements in 3D In Vitro Models for Colorectal Cancer.

The process of drug discovery and pre-clinical testing is currently inefficient, expensive, and time-consuming. Most importantly, the success rate is unsatisfactory, as only a small percentage of tested drugs are made available to oncological patients. This is largely due to the lack of reliable models that accurately predict drug efficacy and safety. Even animal models often fail to replicate human-specific pathologies and human body's complexity. These factors, along with ethical concerns regarding animal use, urge the development of suitable human-relevant, translational in vitro models.

[Scientific methods for in-vitro investigations in the field of joint kinematics : Cluster experimental joint kinematics]. / Wissenschaftliche Methoden bei In-vitro-Untersuchungen im Bereich der Gelenkkinematik : Cluster Experimentelle Gelenkkinematik.

In vitro studies are an established method to determine joint kinematics for answering preclinical questions regarding the effects of new treatment options, surgical techniques or implant designs. The lack of standardized, interdisciplinary representation in the determination of joint kinematics poses a problem. In addition to representation forms such as the "neutral-zero method" or the description of movements within the three basic planes, there are other mathematical joint-specific representations of individual working groups. The International Society of Biomechanics (ISB) has already made recommendations for standardization, but most of these cannot be implemented in biomechanical in-vitro studies. The cluster has therefore set itself the goal of standardizing in-vitro test methods in order to achieve better comparability of scientific results from different working groups.

Do oral antiseptics used in the dental routine have anti-viral efficacy? a systematic review of in vitro studies / Os antissépticos orais utilizados na rotina odontológica têm eficácia anti-viral? Uma revisão sistemática de estudos in vitro / ¿Los antisépticos orales utilizados en la rutina odontológica tienen eficacia antiviral? Una revisión sistemática de estudios in vitro

Introduction: Mouthwashes play an important role in the dental clinic, but their role on viruses requires investigation. Objective:to review in vitro studies to identify the effect of different mouthwashes on the main viruses associated with routine dental care. Methodology:The following databases were searched in September 2023: PubMed, Embase, Scopus and Web of Science databases; the Cochrane Library and the Virtual Health Library (VHL); and grey literature. In vitro studies that used mouthwashes to reduce the viral load were selected. The PICOS strategy was considered to define eligibility criteria: the Population (viruses involved in the etiology of oral infection), the Intervention (oral antiseptics), the appropriate comparator (positive and negative controls), the Outcomes of interest (reduction of viral load) and the Study design (in vitro studies). Results:Considering the eligibility criteria, 19 articles were included in this review. The efficacy of povidone-iodine (PVP-I), chlorhexidine, Listerine®, essential oils, and cetylpyridinium chloride (CPC) rinses were investigated. PVP-I (0.23%) had its effects mainly associated with coronaviruses SARS(Severe Acute Respiratory Syndrome),demonstrating a significant reduction in viral load after 15 seconds of exposure. Chlorhexidine (0.05%; 0.1% and 0.5%) was ineffective against adenovirus, poliovirus, and rhinovirus respiratory viruses. Listerine® demonstrated superior efficacy against HSV-1 and 2 viruses and influenza A, and cetylpyridine chloride also demonstrated virucidal activity against influenza A. Conclusions:The type, concentration, and time of exposure to antiseptics varied between studies. PVP-I and chlorhexidine digluconate were the most studied substances, butin general, PVP-I was more effective in reducing viral titers, especially concerning coronaviruses. Other antiseptics such as CPC, H2O2 and Listerine® have also shown significant reduction in viral load, but this is a limited number of studies (AU).

Introdução: Os enxaguantes bucais desempenham um papel importante na clínica odontológico, porém seu papel sobre os vírus requer investigações. Objetivo: revisar estudos in vitro para identificar o efeito de diferentes colutórios sobre os principais vírus associados ao atendimento odontológico de rotina. Metodologia: As seguintes bases foram pesquisadas até setembro de 2023: PubMed, Embase, Scopus e Web of Science; a Biblioteca Cochrane e a Biblioteca Virtual em Saúde (BVS); e literatura cinzenta. Foram selecionados estudos in vitro que utilizaram bochechos com o objetivo de reduzir a carga viral. A estratégia PICOS foi considerada para a definição dos critérios de elegibilidade: População (vírus envolvidos na etiologia da infecção oral), Intervenção (antissépticos orais), Comparador (controles positivos e negativos), os Desfechos de interesse (redução da carga viral) e o desenho do estudo (estudos in vitro). Resultados: Considerando os critérios de elegibilidade, 19 artigos foram incluídos para esta revisão. A eficácia da povidona-iodo (PVP-I), clorexidina, Listerine®, óleos essenciais e lavagens com cloreto de cetilpiridínio foram investigadas. O PVP-I(0.23%)teve seus efeitos principalmente associados ao coronavírusSARS (Síndrome Respiratória Aguda Severa),demonstrando uma redução significativa da carga viral após 15 segundos de exposição. A clorexidina mostrou-se ineficaz contra vírus respiratórios de adenovírus, poliovírus e rinovírus. Listerine® demonstrou eficácia superior contra vírus HSV-1 e 2 e vírus influenza A, e cloreto de cetilpiridinio também demonstrou atividade virucida contra influenza A.Conclusões:O tipo, concentração e tempo de exposição aos antissépticos variaram entre os estudos. O PVP-I e o digluconato de clorexidina foram as substâncias mais estudadas, mas no geral, o PVP-I foi mais eficaz na redução dos títulos virais, principalmente no que diz respeito aos coronavírus. Outros antissépticos como CPC, H2O2 e Listerine® também mostraram redução significativa da carga viral, mas trata-se de um número limitado de estudos (AU).

Introducción: Los enjuagues bucales son importantesen la clínica dental, sin embargo, su efecto sobre los virus requiere investigaciones. Objetivo: Revisar estudios in vitro para identificar el efecto de enjuagues bucales sobre los principales virus asociados con larutinaodontológica. Metodología: Las siguientes bases de datos fueron investigadas hasta septiembrede 2023: PubMed, Embase, Scopus y Web of Science; Biblioteca Cochrane y Biblioteca Virtual en Salud (BVS); yliteratura gris. Se seleccionaron estudios in vitro que utilizaron enjuagues bucales con el objetivo de reducir la carga viral. Se consideró la estrategia PICOS para definir los criterios de elegibilidad: Población (virus implicados en la etiología de la infección oral), Intervención (antisépticos bucales), Comparador (controles positivos y negativos), Resultados de interés (reducción de la carga viral) y diseño del estudio (in vitro). Resultados: Considerando los criterios de elegibilidad, se incluyeron 19 artículos.Se investigó la eficacia de povidona yodada (PVP-I), clorhexidina, Listerine®,aceites esenciales y enjuagues de cloruro de cetilpiridinio (CPC). PVP-I(0.23%)mostró sus efectos principalmente asociados al coronavirus SARS(Síndrome Respiratorio Agudo Severo), demostrando una reducción significativa de la carga viral después de 15 segundos. Se ha demostrado que la clorhexidina es ineficaz contra losvirus respiratorios adenovirus, poliovirus y rinovirus. Listerine® demostró una eficacia superior contra los virus HSV-1 y 2 y el virus de la influenza A, y el CPCtambién mostró actividad virucida contra la influenza A.Conclusiones: El tipo, la concentración y el tiempo de exposiciónvariaron entre los estudios. PVP-I y digluconato de clorhexidina fueron las sustancias más estudiadas, pero,PVP-I fue más efectiva en la reducción de los títulos virales, especialmente en lo que respecta a los coronavirus. Otros antisépticos como CPC, H2O2 y Listerine® también mostraron una reducción significativa de la carga viral, pero se trata de un número limitado de estudios (AU).

Papel dos receptores farmacológicos AT1 e AT2 da Angiotensina II em doença periodontal induzida: aspectos moleculares / Role of pharmacological receptors AT1 and AT2 of Angiotensin II in caused periodontal disease: molecular aspects

O sistema renina angiotensina (SRA) é de grande importância para o equilíbrio hídrico e regulação da pressão arterial do organismo, além de estar associado ao estimulo de vias próinflamatórias. Seu principal peptídeo é a angiotensina II, que interage principalmente com os receptores do tipo 1 (AT1) e do tipo 2 (AT2). Foi encontrado interrelação entre as doenças cardiovasculares e a periodontite. Este estudo teve como objetivo avaliar os aspectos moleculares em camundongos submetidos a um modelo experimental de periodontite, observando a influência dos receptores de Ang II tipo 1 (AT1(-)) e Ang II tipo 2 (AT2(-)) na periodontite. Métodos: A periodontite experimental foi induzida colocando-se uma ligadura com fio de nylon 5.0 ao redor do segundo molar superior esquerdo de camundongos knockoutAT1(-), AT2(-) e selvagem (WT), subdivididos 2 grupos para cada linhagem: sem ligadura e ligadura, totalizando seis grupos: três controles e três experimentais. Após 15 dias da indução da doença os animais foram submetidos à eutanásia. Com o intuito de avaliar se as variações genéticas teriam influência sobre a periodontite foram realizadas as análises de citocinas, peptídeos e enzimas foram analisados a partir de tecidos gengivais por ELISA e RT-PCR. Resultados: Os animais WT e AT2(-) apresentaram resultados semelhantes em relação às citocinas IL-1ß, IL-6, TNF-α, com aumento dos níveis em relação aos saudáveis (p < 0,001). Houve diferenças significativas em IL-ß entre os grupo AT1(-)-L e WT-L (p < 0,05), e em IL-6 e TNF-α os grupos AT1(-)-L apresentaram diferenças significativas (p < 0,001) tanto quando comparado aos grupo WT-L quanto aos grupos AT2(-)-L. Os níveis de IL-10 foram maiores em WT-L (p < 0,01), enquanto os grupos AT2(-) e AT1(-) não apresentaram alterações significativas em relação a essa citocina. Houve diferenças significativas em Angiotensina II entre os grupos AT2(-)-NL e AT2(-)-L (p < 0,01); e em Angiotensina 1-7 entre os grupos AT1(-)-L e AT2(-)-L (p < 0,05). Para TLR2 houve diferenças entre os grupos WT-NL/WT-L (p < 0,05); AT1(-)-NL/AT1(-)-L (p < 0,01) e AT2(-)-NL/AT2(-) - L (p < 0,01). Para o receptor MAS houve diferenças entre os grupos WT-NL/WT-L (p < 0,001) e AT2(-)-NL/AT2(-)-L (p < 0,001), e também em relação ao grupo WT-L/AT1(-)-L (p < 0,001) e AT1(-)-L/AT2(-)-L (p < 0,001). Para a expressão dos peptídeos ECA e ECA2, houve diferença estatística apenas para ECA entre os tipos de grupos WT-NL/WT-L (p < 0,001). Conclusão: Os animais do grupo AT1(-) apresentaram menor inflamação que as demais linhagens doentes, assim como uma menor expressão do receptor Mas e Ang 1-7. Além disso os animais dos grupos WT e AT2(-) demonstraram resultados próximos em diversas análises, evidenciando que o bloqueio do receptor AT1, sobre os efeitos moleculares, é mais positiva (AU).

The renin angiotensin system (RAS) is of great importance for water balance and regulation of blood pressure in the body, in addition to being associated with the stimulation of proinflammatory pathways. Its main peptide is angiotensin II, which interacts mainly with type 1 (AT1) and type 2 (AT2) receptors. An interrelationship was found between cardiovascular diseases and periodontitis. This study aimed to evaluate the molecular aspects in mice subjected to an experimental model of periodontal disease, observing the influence of Ang II type 1 (AT1(-)) and Ang II type 2 (AT2(-)) receptors on periodontitis. Methods: Experimental periodontitis was induced by placing a ligature with 5.0 nylon thread around the upper left second molar of AT1(-), AT2(-) and wild-type (WT) knockout mice, subdivided into 2 groups for each strain: without ligation and ligation, totaling six groups: three controls and three experimental. After 15 days of disease induction, the animals were euthanized. In order to evaluate whether genetic variations would have an influence on periodontal disease, analyzes of cytokines were carried out, peptides and enzymes were analyzed from gingival tissues by ELISA and RT-PCR. Results: WT and AT2(-) animals showed similar results in relation to the cytokines IL-1ß, IL-6, TNF-α, with increased levels compared to healthy ones (p < 0.001). There were significant differences in IL-ß between the AT1(-)-L and WT-L groups (p < 0.05), and in IL-6 and TNF-α the AT1(-)-L groups showed significant differences (p < 0.001) both when compared to the WT-L and AT2(-)-L groups. IL-10 levels were higher in WT-L (p < 0.01), while the AT2(-) and AT1(-) groups did not show significant changes in relation to this cytokine. There were significant differences in Angiotensin II between the AT2(-)-NL and AT2(-)-L groups (p < 0.01); and in Angiotensin 1-7 between the AT1(-)-L and AT2(-)-L groups (p < 0.05). For TLR2 there were differences between the WT-NL/WT-L groups (p < 0.05); AT1(-)-NL/AT1(-)-L (p < 0.01) and AT2(-)-NL/AT2(-)-L (p < 0.01). For the MAS receptor there were differences between the WT-NL/WT-L (p < 0.001) and AT2(-)-NL/AT2(- )-L (p < 0.001) groups, and also in relation to the WT-L group /AT1(-)-L (p < 0.001) and AT1(-)-L/AT2(-)-L (p < 0.001). For the expression of ACE and ACE2 peptides, there was a statistical difference only for ACE between the types of WT-NL/WT-L groups (p < 0.001). Conclusion: The animals in the AT1(-) group showed less inflammation than the other diseased lines, as well as a lower expression of the Mas and Ang 1-7 receptor. Furthermore, animals from the WT and AT2(-) groups demonstrated similar results in several analyses, showing that the blockade of the AT1 receptor, on molecular effects, is more positive (AU).

Asociación del resultado auditivo final, en pacientes con hipoacusia súbita, a la respuesta a glucocorticoides in vitro / Association of the final hearing result, in patients with sudden hearing loss, to the response to glucocorticoids in vitro

Introducción: La hipoacusia súbita (HS) es poco frecuente y su etiopatogenia no está definida. La terapia con corticoides es de elección en base a recomendaciones de expertos por sus efectos teóricos y no en base a utilidad clínica demostrada. Objetivo: Evaluar si existe correlación entre el resultado auditivo final, de pacientes con HS tratados con corticoides, y la respuesta in vitro de sus leucocitos a corticoides, medida como diferencias en la expresión relativa de genes blanco del receptor de glucocorticoides. Material y Método: Estudio de casos (recuperación total) y controles (no recuperados) de pacientes con HS tratados con corticoides en el Hospital Clínico de la Universidad de Chile, durante 2017-2019. Se obtuvo DNA que fue almacenado en el Biobanco de Tejidos y Fluidos de la Universidad de Chile (BTUCH). Se purificaron y cultivaron leucocitos mononucleares de sangre periférica, expuestos in vitro a hidrocortisona. Se determinó la diferencia en la expresión relativa de genes blanco (IGFBP1, CAT, HSD17B12, APOA2), por Q-RTPCR, entre ambos grupos. Resultados: Se reclutaron 35 pacientes; se incluyeron para análisis 23: 11 casos y 12 controles, con edad promedio de 54,9 y 50,8 años respectivamente, distribución homogénea de sexo. No hubo diferencia estadísticamente significativa en la expresión relativa de los genes blanco, a la exposición in vitro a corticoides, entre ambos grupos. Conclusión: En nuestro estudio, modelo, y sistema de evaluación no se evidenciaron efectos de los corticoides. No podemos descartar que, con un número mayor de pacientes, otros genes blanco u otros protocolos de estudio podrían detectarse diferencias.

Introduction: Sudden hearing loss (SHL) is rare and its etiopathogenesis is still not clear. Corticosteroid therapy is of choice based on expert recommendations due to its theoretical effects and no based on proved clinical efficacy. Objectives: To assess whether there is a correlation between the final auditory outcome of patients with SHL treated with corticosteroids and the in vitro response of their leukocytes to corticosteroids, measured as differences in the relative expression of glucocorticoid receptor target genes. Material and Method: Case-control (total recovery and not recovered respectively) study of patients with SHL treated with corticosteroids at Clinical Hospital Universidad de Chile between 2017 and 2019. DNA was obtained and stored in the Biobanco de Tejidos y Fluidos de la Universidad de Chile (BTUCH). Peripheral blood mononuclear leukocytes were purified and cultured and then exposed to hydrocortisone. The difference in the relative expression of target genes (GFBP1, CAT, HSD17B12, APOA2), by Q-RTPCR was determined. Results: Thirty-five patients were recruited, 24 were included for the analysis: 11 cases and 12 controls, with and average age of 54.9 and 50.,8 years respectively, homogeneous sex distribution. There was no statistically significant difference in the relative expression of the target genes, upon in vitro exposure to corticosteroids, between both groups. Conclusion: In our study, model and evaluation system, no effects of corticosteroids were evidenced. With a larger number of patients, other target genes or other study protocols, we cannot rule out that differences could be detected.

In vitro production of cat-restricted Toxoplasma pre-sexual stages.

Sexual reproduction of Toxoplasma gondii, confined to the felid gut, remains largely uncharted owing to ethical concerns regarding the use of cats as model organisms. Chromatin modifiers dictate the developmental fate of the parasite during its multistage life cycle, but their targeting to stage-specific cistromes is poorly described1,2. Here we found that the transcription factors AP2XII-1 and AP2XI-2 operate during the tachyzoite stage, a hallmark of acute toxoplasmosis, to silence genes necessary for merozoites, a developmental stage critical for subsequent sexual commitment and transmission to the next host, including humans. Their conditional and simultaneous depletion leads to a marked change in the transcriptional program, promoting a full transition from tachyzoites to merozoites. These in vitro-cultured pre-gametes have unique protein markers and undergo typical asexual endopolygenic division cycles. In tachyzoites, AP2XII-1 and AP2XI-2 bind DNA as heterodimers at merozoite promoters and recruit MORC and HDAC3 (ref. 1), thereby limiting chromatin accessibility and transcription. Consequently, the commitment to merogony stems from a profound epigenetic rewiring orchestrated by AP2XII-1 and AP2XI-2. Successful production of merozoites in vitro paves the way for future studies on Toxoplasma sexual development without the need for cat infections and holds promise for the development of therapies to prevent parasite transmission.

Modelos avançados de pele humana 3D in vitro: epiderme bioimpressa e pele tricamada contendo hipoderme para avaliação de segurança e mimético de dermatite atópica nocaute de IL-13Rα2 para estudo da função barreira / Advanced in vitro 3D human skin models: bioprinted epidermis and trilayer skin containing hypodermis for safety assessment and atopic dermatitis mimetic with IL-13Rα2 knockout for barrier function study

A reconstrução de modelos avançados de pele tridimensional in vitro, que corresponda de forma mais fidedigna ao complexo microambiente da pele humana, depende da utilização de inovações tecnológicas e da adição de novos tipos celulares representativos da pele humana. Desta maneira, estes miméticos fornecem uma plataforma de alta relevância para estudos de fisiopatologia da pele, além de propiciar um sistema para a avaliação da segurança e eficácia de cosméticos e medicamentos alternativo ao uso de animais. Dessa maneira, o Capítulo I compara a performance de uma epiderme reconstruída humana (RHE) bioimpressa com a manual utilizando o teste in vitro de irritação cutânea descrito no guia OCDE número 439. Nossos resultados demonstram que ambos os modelos de pele exibiram morfologia estratificada e a função barreira epidérmica equivalente aos modelos validados. Nos testes de irritação in vitro, ambos modelos distinguiram corretamente as substâncias de referência, classificadas entre irritantes ou não-irritantes de acordo com o limiar de viabilidade de 50%. Esse resultado indica que a bioimpressora poderia ser de grande utilidade para a automação da reconstrução de modelos epidérmicos. O tecido hipodérmico possui importante papel na homeostase da pele humana. O Capítulo II aborda a reconstrução de uma pele tricamada, contendo a camada hipodérmica, além da epiderme e derme. Usando esferoides de adipócitos diferenciados in vitro, um modelo de pele tricamada em matriz de colágeno foi construído. Ao comparar este com a pele bicamada obtivemos maior expressão de loricrina e involucrina no modelo tricamada, indicando um potencial para maior função barreira, além de maior expressão de PPAR-γ. Testes de função barreira através da resistividade elétrica não demonstraram diferenças entre os modelos, mas a aplicação de SDS a 5 mg/ml por 18 horas induziu o aumento da viabilidade na pele tricamada. Além disso, após a aplicação de SDS a 2,5% para induzir uma irritação aguda, seguida de recuperação por 42h, obtivemos maior viabilidade na pele tricamada, indicando melhor recuperação pós-lesão irritativa induzida. A pele tricamada é promissora para estudos do metabolismo da pele humana e recuperação de lesões. A dermatite atópica (DA) é uma doença eczematosa de pele caracterizada por inflamação do tipo Th2 e alteração da barreira epidérmica. IL-13 e IL-4 são centrais no comprometimento da barreira epidérmica na DA. Entre os receptores de IL-13 em queratinócitos, o receptor IL-13Rα2, tem um papel controverso na alteração da barreira cutânea. O objetivo do Capítulo III foi estudar a deleção da expressão de IL-13Rα2 em RHE, que foram expostas a IL-4 e IL-13, e avaliadas conforme a expressão dos receptores e de proteínas alteradas na DA. As epidermes com knockout em IL-13Rα2 apresentaram redução da expressão de NELL2 (p<0,0021), tipicamente aumentadas na DA. Além disso, houve redução da expressão do receptor do IL-2Rγ. Assim, um possível papel de exacerbação da DA do receptor IL-13Rα2 deve ser estudado mais extensamente para ser caracterizado

The reconstruction of advanced three-dimensional in vitro skin models, which more reliably correspond to the complex microenvironment of human skin, depends on the use of technological innovations and the addition of new cell types representative of human skin.In this way, these mimetics provide a highly relevant platform for studies of skin pathophysiology, in addition to providing a system for evaluating the safety and efficacy of cosmetics and medicines alternative to animal use. In this way, Chapter I compares the performance of a bioprinted human reconstructed epidermis (RHE) with a manual one using the in vitro skin irritation test described in OECD guide number 439. Our results demonstrate that both skin models exhibited stratified morphology and the epidermal barrier function equivalent to validated models. In in vitro irritation tests, both models correctly distinguished the reference substances, classified as irritating or non-irritating according to the viability threshold of 50%. This result indicates that the bioprinter could be of great use for automating the reconstruction of epidermal models Hypodermic tissue plays an important role in the homeostasis of human skin. Chapter II addresses the reconstruction of a three-layer skin, containing the hypodermic layer, in addition to the epidermis and dermis. Using in vitro differentiated adipocyte spheroids, a trilayer skin model in collagen matrix was constructed. When comparing this with bilayer skin, we obtained greater expression of loricrin and involucrin in the trilayer model, indicating a potential for greater barrier function, in addition to greater expression of PPAR-γ . Barrier function tests using electrical resistivity did not demonstrate differences between the models, but the application of SDS at 5 mg/ml for 18 hours induced an increase in viability in the three-layer skin. Furthermore, after applying 2.5% SDS to induce acute irritation, followed by recovery for 42 hours, we obtained greater viability in the three-layer skin, indicating better recovery after induced irritant injury. Trilayer skin holds promise for studies of human skin metabolism and injury recovery. Atopic dermatitis (AD) is an eczematous skin disease characterized by Th2-type inflammation and alteration of the epidermal barrier. IL-13 and IL-4 are central to the impairment of the epidermal barrier in AD. Among the IL-13 receptors on keratinocytes, the IL-13Rα2 receptor has a controversial role in altering the skin barrier. The objective of Chapter III was to study the deletion of IL-13Rα2 expression in RHE, which were exposed to IL-4 and IL-13, and evaluated according to the expression of receptors and proteins altered in AD. Epidermis with IL-13Rα2 knockout showed reduced NELL2 expression (p<0.0021), typically increased in AD. Furthermore, there was a reduction in the expression of the IL-2Rγ receptor. Therefore, a possible AD exacerbation role of the IL-13Rα2 receptor should be studied more extensively to be characterized

Interação de cepas de Lactobacillus crispatus com Streptococcus agalactiae em culturas celulares mimetizando o ambiente vaginal / Interaction between Lactobacillus crispatus and Streptococcus agalactiae strains in cell cultures mimicking the vaginal environment

A microbiota vaginal é dominada pelo gênero Lactobacillus, mantendo um pH ácido crucial para a saúde. Alterações hormonais e a menopausa podem impactar essa microbiota. Estreptococos do Grupo B (EGB) são associados a infecções neonatais e podem colonizar a microbiota vaginal. A interação entre Lactobacillus e EGB é complexa, com resultados conflitantes em estudos in vitro e in vivo. O uso de probióticos contendo Lactobacillus pode ter benefícios, como alterar a positividade para EGB em um grupo que recebeu o tratamento. Contudo a replicabilidade deste resultado é limitada, e os mecanismos envolvidos nessa interação ainda são pouco elucidados. Portanto o objetivo desse estudo foi caracterizar cepas de EGB, avaliar sua interação com L. crispatus em diversas condições. Neste estudo foram selecionadas seis cepas, pertencentes aos sorotipos Ia, II, III e V. Essas cepas foram caracterizadas de acordo com o sorotipo capsular, presença de genes de virulência (hialuronidase, ß-citolisina/hemolisina, e ilhas de pili 1, 2a e 2b), resistência a antimicrobianos (penicilina, cefepima, vancomicina, eritromicina e clindamicina), curva de crescimento, Restriction Fragment Length Polymorphism (RFLP) e Multi-Locus Sequence Typing (MLST). O resultado de MLST identificou os sequence types ST1, ST23 ST28 e ST182, e os clonal complexes CC1, CC19 e CC23. Cepas possuem a maior parte dos genes de virulência testados. Somente uma cepa apresentou alguma resistência, no caso à eritromicina e clindamicina. Resultados que estão de acordo com a literatura como os principais descritos em isolados clínicos. Os ensaios de interação realizados foram: crescimento em co-cultura, formação de biofilme, ensaios de adesão e exclusão em cultura celular e por fim, análise do perfil proteico. Alguns efeitos de L. crispatus no EGB observados foram aumento na formação de biofilme de EGB e diminuição da sua proliferação quando em co-cultura. Contudo esses resultados variaram de acordo com a cepa de EGB. Nos ensaios de competição em cultura celular, a presença de L. crispatus levou à diminuição da adesão em uma cepa pertencente ao sorotipo III, e aumento de adesão em uma cepa pertencente ao sorotipo V. Quando a cultura de células recebeu tratamento prévio de L. crispatus, nos ensaios de exclusão, houve menor adesão de EGB. Contudo todos os efeitos observados são cepa-dependente; não foram encontradas associações entre o comportamento das cepas e seu sorotipo capsular ou fenótipo MLST. Estudos futuros podem elucidar as respostas ativadas na presença de microrganismos comensais

The vaginal microbiota is dominated by the genus Lactobacillus, which helps to maintain a crucial acidic pH for health. Hormonal changes and menopause can impact this microbiota. Group B Streptococcus (GBS) are associated with neonatal infections and can colonize the vaginal microbiota. The interaction between Lactobacillus and GBS is complex, with conflicting results in in vitro and in vivo studies. The use of probiotics containing Lactobacillus may have benefits, such as altering GBS positivity in a treated group. However, the replicability of this result is limited, and the mechanisms involved in this interaction are still poorly understood. The use of probiotics containing Lactobacillus may have some benefits, but further research is needed. These strains were characterized based on capsular serotype, presence of virulence genes (hyaluronidase, ß-cytolysin/hemolysin, and pili islands 1, 2a, and 2b), antimicrobial resistance (penicillin, cefepime, vancomycin, erythromycin, and clindamycin), growth curve, Restriction Fragment Length Polymorphism (RFLP), and Multi-Locus Sequence Typing (MLST) Therefore, the aim of this study was to characterize GBS strains, evaluate their interaction with L. crispatus under various conditions. Six strains were selected for this study, belonging to serotypes Ia, II, III, and V. MLST results identified sequence types ST1, ST23, ST28, and ST182, and clonal complexes CC1, CC19, and CC23. Most strains possessed the tested virulence genes, with only one strain showing resistance to erythromycin and clindamycin. These results are in line with the literature. Interaction assays included co-culture growth, biofilm formation, adhesion and exclusion assays in cell culture, and, finally, protein profile analysis. Some observed effects of L. crispatus on GBS included an increase in GBS biofilm formation and a decrease in GBS proliferation during co-culture. However, these results varied according to the GBS strain. GBS interaction with L. crispatus resulted in increased biofilm formation and decreased proliferation in co-culture. In cell culture competition assays, the presence of L. crispatus led to decreased adhesion in one GBS strain belonging to serotype III and increased adhesion in one strain belonging to serotype V. When cell culture received pre-treatment with L. crispatus, exclusion assays showed lower GBS adhesion. However, all observed effects are strain-dependent; no associations were found between strain behavior and capsular serotype or MLST phenotype. Future studies may elucidate the responses activated in the presence of commensal microorganisms

Effect of Toothpaste Fluoride Concentration on Color Stability of Resin Composites: An In Vitro Study

ABSTRACT Objective: To investigate the effects of two different dentifrice fluoride concentrations on the color stability of the composite. Material and Methods: Twenty-seven specimens (2×4×5 mm) each of microfilled (Gradia, GC, Japan) and nanohybrid (Grandio, VOCO, Germany) composites were prepared. The specimens were randomly divided into six groups (control, Fluoflor caries protection toothpaste with 1450ppm Fluoride (EXW, France), and Fluoflor kids toothpaste with 500ppm Fluoride (EXW, France) (n = 9). The specimens were immersed in a mixture of artificial saliva and toothpaste in a ratio of 1:3 and applied for 60 seconds every 12 hours for 42 days. The control samples were incubated in artificial saliva at 37°C. Primary and secondary color measurements were performed using color parameters (L∗a∗b) with a spectrophotoshade (MHT Optic Research AG, Niederhasli, Switzerland). Data were analyzed using a two-way analysis of variance at a significance level of 0.05. Results: According to the two-way ANOVA analysis, there was no significant difference in color change between the composites and no difference in the level of discoloration between different fluoride concentrations(p>0.05). Also, None of the dentifrices caused clinically significant color changes(∆E˂3.3). Conclusion: No clinically unacceptable color changes were observed in the microfilled and nanofilled composites with different concentrations of fluoride toothpaste.

Regulação da Septina 9 na síndrome do desconforto respiratório agudo associado à malária / The role of Septin 9 in regulating vascular permeability in malarial respiratory distress syndrome

A malária é um problema mundial de saúde, com 249 milhões de casos de infecção, ocasionando 608 mil mortes no ano de 2022. Causada pelo gênero Plasmodium, são cinco principais espécies causadoras da malária no ser humano, o Plasmodium malariae, Plasmodium ovale, Plasmodium knowlesi, Plasmodium vivax e Plasmodium falciparum sendo os dois últimos responsáveis pelo maior número de casos clínicos e mortes ao redor do mundo, transmitida pelo mosquito fêmea do gênero Anopheles durante o repasto sanguíneo. Sabe-se ainda que eritrócitos infectados por Plasmodium berghei ANKA causam alteração no citoesqueleto de actina, consequentemente levando a hiperpermeabiliade da barreira endotelial. Em experimentos in vitro, a imunofluorescência, foi observada alteração do citoesqueleto de actina em células estimuladas com eritrócitos parasitados por PbA (EP), em contrapartida, aquelas não estimuladas (NE) e estimuladas com eritrócitos não parasitados por PbA (EnP), não mostraram alterações no mesmo. Nos experimentos in vivo, ao observar dados coletados, sendo estes respiratórios (penh e frequência respiratória) e parasitemia coletados no 7º DPI, foi observado um mesmo padrão entre o experimento 1 e o experimento 2. Os animais infectados com 106 de eritrócitos infectados, foram alocados em dois grupos, sendo eles hiperparasitemia (HP) ou síndrome do desconforto respiratório agudo-associado a malária (SDRA/SDRA-MA) e comparados àqueles não infectados (NI). Os animais NI, não apresentam parasitemia, em contrapartida, os animais SDRA, tem maior parasitemia que os HP, visto que estes têm aumento em sua parasitemia após o 12º DPI, e assim seguem aumentando gradativamente até levar os animais a óbito.O penh tem o mesmo padrão que a parasitemia, os NI com penh mais baixa que os HPs e os SDRA, sendo dentre estes, o grupo SDRA o mais elevado. A frequência respiratória, por sua vez se apresenta mais elevada no grupo NI, sendo o grupo SDRAmenor que o HP, um achado tido como normal, visto que os pulmões de animais com SDRA sofrem maior dano que os HPs. Apesar de não apresentar um valor significativo, as imagens de gel SDS-PAGE (WB) mostram maior concentração da Septina 9 nos animais com SDRA em comparação com os HPs e com os NIs. O mesmo é observado na qRT-PCR, mesmo sem significância estatística, o valor mostrado nos gráficos temmaior concentração nos SDRA. Assim, a Septina 9 está presente nas CEPP, e, mesmo sem significância estatística, da mesma forma que está presente nas amostras de tecido pulmonar utilizadas no WB e qT-PCR. É hipotetizado ainda que esta proteína pode ser ativada e assim sofrer alteração em sua localização intracelular

Malaria is a global health problem, with 249 million cases of infection, causing 608 thousand deaths in the year 2022. Caused by the genus Plasmodium, there are five main species that cause malaria in humans, Plasmodium malariae, Plasmodium ovale, Plasmodium knowlesi, Plasmodium vivax and Plasmodium falciparum, the last two being responsible for the largest number of clinical cases and deaths around the world, transmitted by the female mosquito of the genus Anopheles during blood meal. It is also known that erythrocytes infected by Plasmodium berghei ANKA (PbA) cause changes in the actin cytoskeleton, consequently leading to hyperpermeability of the endothelial barrier. In in vitro experiments, immunofluorescence, changes in the actin cytoskeleton were observed in cells stimulated with erythrocytes parasitized by PbA (EP), in contrast, those not stimulated (NE) and stimulated with erythrocytes not parasitized by PbA (EnP), did not show changes the same. In the in vivo experiments, when observing collected data, these being respiratory (penh and respiratory frequency) and parasitemia collected on the 7th DPI, the same pattern was observed between experiment 1 and experiment 2. Animals infected with 106 infected erythrocytes were allocated into two groups, namely hyperparasitemia (HP) or malaria-associated acute respiratory distress syndrome (ARDS/ARDS-MA) and compared to those not infected (NI). NI animals do not present parasitemia, on the other hand, ARDS animals have greater parasitemia than HP animals, as the latter have an increase in their parasitemia after the 12th DPI, and thus continue to gradually increase until the animals die. the same pattern as parasitemia, NI with lower penh than HPs and ARDS, among these, the ARDS group being the highest. The respiratory rate, in turn, is higher in the NI group, with the ARDS group being lower than the HP, a finding considered normal, given that the lungs of animals with ARDS suffer greater damage than the HPs. Despite not showing a significant value, SDS-PAGE (WB) gel images show a higher concentration of Septin 9 in animals with ARDS compared to HPs and NIs. The same is observed in qRT-PCR, even without statistical significance, the value shown in the graphs has a higher concentration in ARDS. Thus, Septin 9 is present in CEPP, and, even without statistical significance, in the same way that it is present in lung tissue samples used in WB and qT-PCR. It is also hypothesized that this protein can be activated and thus undergo changes in its intracellular location

Effect of Water and Chlorhexidine with Different Pressures of Oral Irrigation Device on the Surface Roughness and Topography of Giomer

Abstract Objective: To evaluate the effect of different pressures of an oral irrigation device (OID) and the irrigation solution type on the surface roughness of the giomer restorative material. Material and Methods: In this in vitro study, disk-shaped giomer samples were fabricated and assigned to 5 groups (n=23): Group 1, storage in distilled water (control); Group 2, OID #7 pressure/ water; Group 3, OID #10 pressure/ water; Group 4, OID #7 pressure/ 0.05% CHX; Group 5, OID #10 pressure/ 0.05% CHX. The samples' treatment simulated a one-year application of OID. Surface roughness (Ra) and topography of the giomer were evaluated using profilometry and scanning electron microscopy. The data were analyzed with Paired t-test, Tukey, and ANOVA tests (α=0.05). Results: The Ra of the samples increased significantly after treatment with OID (p<0.001). The roughness increase in groups with a pressure of 10 was higher than those with a pressure of 7 (p<0.001). The effect of pressure on surface changes was significant (p<0.001). However, the solution type and the cumulative effect of these two factors were insignificant (p=0.08 and p=0.43, respectively). Conclusion: Oral irrigation device with both solutions significantly increased the surface roughness and topographic changes of the giomer. The severity of these changes was related to the device's pressure.

Hymenaea rubriflora Ducke stem bark extract has vasorelaxant and contractile inhibition capacity

Abstract We investigated the vasodilatory effects of Hymenaea rubriflora Ducke stem bark extract (HRHAc). Vascular reactivity of the aortic rings of Wistar rats was tested by in vitro cumulative doses (0.1 - 729 µg/mL). Rats (n=5) were treated with 25 (G25), 50 (G50) and 100 (G100) mg/ kg of HR-HAc or saline (control group - CG) for four weeks. An in vitro assay resulted in dose-dependent relaxation of the aortic rings with functional endothelium, which was inhibited in the presence of L-NAME. Rings of the treated animals increased acetylcholine relaxing potency at all doses, with a greater effect on G50 (pD2 = 7.8±0.1, Emax = 95.6±1.1) and a decreased contractile potency to phenylephrine in G25 (pD2 = 6.9±0.06, Emax = 61.5±6.0%) and G50 (pD2= 6.6±0.06, Emax = 71.0±8.5%) when compared to the CG in the presence and absence of endothelium (pD2= 6.4± 0.1, 6.4±0.1 and 6.9±0.1, respectively). Cumulative doses of nitroprusside resulted in increased relaxing potency in all treated groups and maintained Emax at 100%. It is concluded that HR-HAc has vasorelaxant capacity and inhibitory vascular contraction activity applied either directly to aortic rings or after treatment with in vivo supplementation, which places this extract as a potential nutraceutical or pharmacological agent for treating diseases associated with vascular dysfunction.

Multiplication, morphogenesis and foliar abscision of Schinopsis brasiliensis Engl. in vitro / Multiplicación, morfogénesis y abscisión foliar de Schinopsis brasiliensis Engl. in vitro

The objective was to evaluate plant growth regulators and ethylene inhibitors on the development and leaf abscission of Schinopsis brasiliensis Engl. Zeatin (ZEA) was evaluated in concentrations combined with concentrations of indolacetic acid (IAA), naphthalene acetic acid (NAA) and indolbutyric acid (IBA). ZEA and 6-benzylamino purine (BAP) were evaluated in concentrations plus a control. Ethylene inhibitors, silver nitrate and cobalt chloride were evaluated in four concentrations. The addition of 0.2 µL-1 of NAA to 0.4 µL-1 of ZEA promotes a greater number of baraúna sprouts. At concentrations of 5 and 10 µM, cobalt chloride is more efficient than silver nitrate for reducing leaf abscission in baraúna. IAA is the most suitable auxin to be associated with ZEA for higher shoot length and number of buds. Silver nitrate from a concentration of 20 µM completely avoids leaf abscission whilecobalt chloride has a maximum reduction in abscission at a concentration of 40 µM.

El objetivo fue evaluar reguladores de crecimiento e inhibidores de etileno sobre el desarrollo y abscisión foliar en Schinopsis brasiliensis Engl. La zeatina (ZEA) se evaluó en concentraciones combinadas con concentraciones de ácido indolacético (IAA), ácido naftaleno acético (NAA) y ácido indolbutírico (IBA). Se evaluaron ZEA y 6-bencilamino purina (BAP) en concentraciones más un control. Se evaluaron inhibidores de etileno, nitrato de plata y cloruro de cobalto, en cuatro concentraciones. La adición de 0.2 µL-1 de NAA a 0.4 µL-1 de ZEA promueve un mayor número de brotes de baraúna. A concentraciones de 5 y 10 µM, el cloruro de cobalto es más eficaz que el nitrato de plata para reducir la abscisión de las hojas en baraúna. IAA es la auxina más adecuada para asociar con ZEA para una mayor longitud de brotes y número de brotes. El nitrato de plata a partir de una concentración de 20 µM evita completamente la abscisión de las hojas, mientras que el cloruro de cobalto tiene una reducción máxima en la abscisión a una concentración de 40 µM.

Comparison Between Radiographs, White and Fluorescent Images in the Diagnosis and Treatment Decisions for Occlusal Caries: An Ex Vivo Study

ABSTRACT Objective: To compare the agreement of images in white light (WL), fluorescence (FL), and digital radiographs (DR), on the diagnosis and treatment decisions for occlusal caries lesions against a micro-CT gold standard. Material and Methods: Ten extracted third molars, with enamel and/or dentin caries (ICDAS 2-4), were included. Occlusal surface images were acquired with an intraoral camera (SoproLife®) in WL and FL modes. DR was obtained using an intraoral X-ray and a semi-direct digital system. A total of 780 images were needed, organized in a template, to be later examined by twenty-six dentists invited to compose the study. The Generalized Estimation Equations model was used to compare the proportions of the correct answers between the three methods and the gold standard. When significant, Bonferroni post-hoc test was used to identify differences (α=5%). Results: Most of the examiners were specialists (76.9%) with 14.5 years of experience. All diagnostic methods were similar and showed low agreement (DR 12.7%, WL 16.5%, and FL 16.5%) compared with gold standard caries diagnostic scores. Regarding treatment decisions, mean agreement for all diagnostic methods was higher (43.2%; p<0.001), and among all methods, WL (48.1%) and FL (51.2%) modes performed better than DR (30.4%, p<0.001). Conclusion: SoproLife® images could help clinicians to propose rational, minimally invasive treatments for occlusal caries lesions.

Moderate Toxicity of Potential Boron-containing Therapeutic, Dipotassium-trioxohydroxytetrafl uorotriborate - K2 (B3 O3 F4 OH) in Rats and Mice

Abstract Biological activity of boron-containing compounds (BCCs) has been well-known. Growing interest and numerous applications for BCCs have been reported. Boron and boron-containing acids show low acute toxicity in mammals but data on halogenated boroxine (HB) - dipotassium-trioxohydroxytetrafluorotriborate, K2(B3O3F4OH) acute toxicity have not been reported before. This compound, characterized as a potential therapeutic for skin changes, exhibits no observable genotoxicity in doses lower that 0.1 mg/ml in vitro and 55 mg/kg in vivo. It has also been confirmed as an antitumour agent both in vitro and in vivo as well as an inhibitor of enzymes involved in antioxidant mechanisms. The aim of this study was to assess the acute toxicity of HB and to determine the maximum tolerated dose as well as a dose free of any signs of toxicity in different test organisms. Acute toxicity of HB was tested in Sprague-Dawley and Wistar rats and BALB/c mice after single parenteral application of different doses. We determined doses free of any sign of toxicity and LD50 after single dose administration. LD50 of HB ranges from 63 to 75 mg/kg in different test models, meaning that HB shows moderate toxicity

Investigation on formulation parameters of donepezil HCl loaded solid lipid nanoparticles

Abstract Donepezil-HCl is a member of the acetylcholinesterase inhibitors that is indicated for the symptomatic treatment of Alzheimer's disease (AD) and has many side effects. In this study, to reduce the side effects of Donepezil-HCl and increase the penetration of the drug through the blood-brain barrier, we aimed to design a solid lipid nanoparticle (SLN) formulation. The effects of the different formulation parameters, such as homogenization speed, sonication time, lipid and drug concentration, surfactant type and concentration, and volume of the aqueous phase, were assessed for optimization. The particle size and PDI increased with increasing lipid concentration but decreased with increasing amounts of surfactant (Tween 80) and co-surfactant (lecithin). When the homogenization rate and sonication time increased, the particle size decreased and the encapsulation efficiency increased. The optimized formulation exhibited particle size, PDI, encapsulation efficiency, and zeta potential of 87.2±0.11 nm; 0.22±0.02; 93.84±0.01 %; -17.0±0.12 mV respectively. The in vitro release investigation revealed that approximately 70% of Donepezil-HCl was cumulatively released after 24 hours. TEM analysis proved that spherical and smooth particles were obtained and formulations had no toxic effect on cells. The final optimized formulation could be a candidate for Donepezil-HCl application in Alzheimer's treatment with reduced side effects and doses for patients

Effect of polycaprolactone nanocapsules loaded with essential oils on biofilm formation by Staphylococcus aureus strains isolated from bovine mastitis cases

Abstract Bovine infectious mastitis is largely resistant to antibacterial treatment, mainly due to mechanisms of bacterial resistance in the biofilms formed by Staphylococcus aureus. Melaleuca (MEO) and citronella essential oils (CEO) are promising agents for reducing or eliminating biofilms. Free melaleuca oil presented a medium Minimum Inhibitory Concentration (MIC) of 0.625% and a Minimum Bactericidal Concentration (MBC) of 1.250%, while free citronella oil showed medium MIC and MBC of 0.313%. Thus, free CEO and MEO demonstrate bacteriostatic and bactericidal potential. We generated polymeric nanocapsules containing MEO or CEO and evaluated their efficacy at reducing biofilms formed by S. aureus. Glass and polypropylene spheres were used as test surfaces. To compare the responses of free and encapsulated oils, strains were submitted to 10 different procedures, using free and nanoencapsulated essential oils (EOs) in vitro. We observed no biofilm reduction by MEO, free or nanoencapsulated. However, CEO nanocapsules reduced biofilm formation on glass (p=0.03) and showed a tendency to diminish biofilms on polypropylene (p=0.051). Despite nanoencapsulated CEO reducing biofilms in vitro, the formulation could be improved to modify the CEO component polarity and, including MEO, to obtain more interactions with surfaces and the biofilm matrix

Development and characterization of photoprotective nanoemulsions containing Babassu (Orbignya phalerata Mart. ) lipophilic extract

Abstract Oil-in-water photoprotective nanoemulsions (NEs) were developed using Babassu (BBS) lipophilic extract, nonionic surfactants, and low concentrations of organic sunscreens by ultrasonic processing. BBS extract was chosen due to its suitable physicochemical properties (acidity index, peroxide index, refraction index, and relative density) and predominance of saturated fatty acids, identified by gas chromatography-mass spectrometry (GC-MS), which promote biological activities and high oxidative stability. NEs were characterized by mean droplet size, morphology, polydispersity index (PdI), pH, and organoleptic properties, and the physical stability of the NEs was evaluated for 120 days at room temperature. The sun protection factor (SPF) was determined, and the photostability and in vitro cytotoxicity assays were performed for NEs. All NEs remained stable for 120 days, with a droplet size <150 nm and a monomodal distribution profile. The pH values were compatible with the skin's pH. NE3 showed a spherical morphology, with a mean droplet size of 125.15 ± 0.16 nm and PdI of 0.145 ± 0.032. NE3 containing BBS extract and sunscreens presented an SPF of 35.5 ± 3.0, was photostable after 6 h of radiation and was non-cytotoxic to fibroblast cells. Thus, NE3 could be considered a promising formulation for developing synergic plant-extract sunscreen photoprotective products for the market

O efeito do tratamento com rapamicina em órgãos linfoides de camundongos propensos à senescência acelerada / The effect of rapamycin treatment on lymphoid organs of senescence accelerated mice prone

Envelhecer compreende um fenômeno complexo, natural e irreversível, que submete o organismo a inúmeras alterações nos processos biológicos, fisiológicos, ambientais, psicológicos, comportamentais e sociais. Esse processo é caracterizado por um declínio gradual dos mecanismos homeostáticos do organismo, intimamente relacionados com o estado senescente. A senescência, quando diz respeito ao sistema imunológico, é denominada de imunossenescência, que pode ser definida como uma parada estável do ciclo celular associada a mudanças, com uma resposta que limita a proliferação de células envelhecidas ou danificadas. A autofagia está diretamente relacionada com a manutenção do fenótipo senescente, em que a atividade autofágica exerce um papel essencial e ativo na influência da biossíntese de proteínas e organelas. Essa via é regulada naturalmente pela proteína mTOR e quimicamente pelo fármaco rapamicina. Assim, pretendemos investigar: (1) as alterações no perfil corporal e hematimêtrico dos animais ao longo do tratamento com rapamicina; (2) avaliar o perfil de citocinas; (3) observar as modificações histológicas em órgãos linfoides primários e secundário; (4) analisar as populações de células linfoides e mieloides; e (5) avaliar a capacidade proliferativa de linfócitos in vitro. Camundongos SAMP-8 e SAMR-1 foram tratados com rapamicina durante dois meses. A mensuração da massa corporal e análises hematológicas foram realizadas antes e durante o tratamento. Amostras de soro, medula óssea, timo e baço foram analisados em ensaios de ELISA, histologia, população e subpopulações de células. Alterações na massa corporal, parâmetros hematológicos e celularidade de células foram nítidas entre os dois modelos utilizados. Diferenças também foram percebidas na detecção de citocinas IL-1ß. IL-6 e TNF-α, com resultados significantes nas amostras de baço, timo e medula óssea. As citocinas IL-7 e IL-15 apresentaram diferenças de secreção entre os grupos, sendo a primeira maior detectada em camundongos com senescência acelerada tratados com rapamicina. Em nossa análise histológica observamos que os camundongos SAM-P8 apresentaram involução tímica. E nas subpopulações de linfócitos T do baço, células TCD4+ e TCD8+ estavam, respectivamente, em maior e menor quantidade nos camundongos SAM-P8 tratados com rapamicina. Dessa forma, o camundongo da linhagem SAM-P8 é um excelente modelo para se estudar as alterações da senescência, em que o mesmo apresenta características fisiológicas distintas dos camundongos utilizados como controle (SAM-R1). Além disso, verificamos que a dose de rapamicina empregada não desencadeou alterações que pudessem comprometer a resposta imunológica desses camundongos, bem como na possibilidade de atuar na resposta contra os efeitos complexos do envelhecimento

Aging comprises a complex, natural, and irreversible phenomenon, which subjects the organism to countless alterations in biological, physiological, environmental, psychological, behavioral, and social processes. This process is characterized by a gradual decline in the organism's homeostatic mechanisms, closely related to senescence effects. Senescence, when it concerns the immune system, is called immunosenescence, which can be defined as a stable cell cycle arrest associated with changes and is a response that limits the proliferation of aged or damaged cells. Autophagy is a genetically regulated, conserved cellular process and a metabolic pathway essential for maintaining cellular homeostasis, which plays a constitutive and active role in controlling the biosynthesis of proteins and organelles. This pathway is regulated naturally by mTOR or chemically by the drug rapamycin, having a direct relationship with cellular homeostasis and maintenance of the senescent phenotype. Thus, we intend to investigate: (1) the changes in the body and hematimetic profile of the animals throughout the rapamycin treatment; (2) evaluate the cytokine profile; (3) observe histological changes in primary and secondary lymphoid organs; (4) analyze lymphoid and myeloid cell populations; and (5) evaluate the proliferative capacity of lymphocytes in vitro. SAMP-8 and SAMR-1 mice were treated with rapamycin for two months. Body mass measurement and hematological analyses were performed before and during treatment. Serum, bone marrow, thymus and spleen samples were analyzed in ELISA assays, histology, cell population and subpopulations. Changes in body mass, hematological parameters, and cellularity were clear between the two models used. Differences were also noticed in the detection of cytokines IL-1ß. IL-6 and TNF-α, with significant results in the spleen, thymus and bone marrow samples. The cytokines IL-7 and IL-15 showed differences in secretion between groups, the former being higher detected in mice with accelerated senescence treated with rapamycin. In our histological analysis we observed that SAM-P8 mice showed thymic involution. And in the spleen T-lymphocyte subpopulations, TCD4+ and TCD8+ cells were, respectively, in higher and lower quantities in SAM-P8 mice treated with rapamycin. Thus, the SAM-P8 mouse is an excellent model to study the changes of senescence, since it presents physiological characteristics different from the control mice (SAM-R1). Furthermore, we verified that the dose of rapamycin used did not trigger changes that could compromise the immune response of these mice, as well as the possibility of acting in the modulatory response against the complex effects of aging

Bioactivity evaluation of least explored traditionally acclaimed medicinally potent herb Nanorrhinum ramosissimum(Wall. ) Betsche

Abstract Present study analysed the therapeutic potential of traditionally acclaimed medicinal herb Nanorrhinum ramosissimum, using plant parts extracted with different solvents (10 mg/mL). Shoot extracts exhibited comparatively better antimicrobial properties, in comparison to root extracts. Total phenolic content was estimated, to ascertain its dependency on antioxidant properties of plant extracts. Antioxidant assay revealed promising results in comparison to IC50 value of standard ascorbic acid (52.2±0.07 µg/mL), for methanolic extracts of shoot (61.07±0.53 µg/mL and 64.33±0.33 µg/mL) and root (76.705±0.12 µg/mL and 89.73±0.28 µg/ mL) for in vivo and in vitro regenerants respectively. Correlation coefficient R2 values ranged between 0.90-0.95, indicating a positive correlation between phenolic contents and antioxidant activity. Plant extracts were also able to inhibit DNA oxidative damage again indicating their antioxidative potential. Antidiabetic potential was confirmed by alpha amylase inhibition assay where shoot methanolic extracts (invivo, in vitro) exhibited the best IC50 values (54.42±0.16 µg/mL, 66.09±0.12 µg/mL) in comparison to standard metformin (41.92±0.08 µg/mL). Ethanolic extracts of roots (in vitro, invivo) exhibited the relative IC50 values (88.97±0.32µg/mL,96.63±0.44 µg/mL) indicating that shoot parts had a better alpha amylase inhibition property; thus proving the herb's bioactive potential and its prospective therapeutic source for curing various ailments.