Sens-ocular model: Cell-based assay to evaluate eye stinging potential of chemicals and baby cosmetic formulations.

The TRPV1 receptor, which is known to contribute significantly to pain perception, has recently been identified as a useful tool for predicting eye stinging potential in cosmetics. In this study, HEK-293 cells with high TRPV1 expression were utilized to evaluate calcium influx related to receptor activation triggered by chemicals and cosmetic formulations. The cells were exposed to increasing concentrations of substances to cause or not some aggression to the eye, and TRPV1 activity was assessed by measuring intracellular FURA-2 AM fluorescence signal. To confirm TRPV1 channel activation, capsazepine, a capsaicin antagonist, was employed in addition to using capsaicin as a positive control. The study's results indicate that this novel model can identify compounds known to cause some aggression to the eye, such as stinging, considering a cut-off value of 60% of Ca2+ influx exposed to the lowest evaluated concentration (0.00032%). When applied to the cosmetic baby formulation, although the presented model exhibited higher sensitivity by classifying as stinging formulations that had previously undergone clinical testing and were deemed non-stinging, the assay could serve as a valuable in vitro tool for predicting human eye stinging sensation and can be used as a tier 1 in an integrated testing strategy.

Chitosan-Calcium Aluminate as a Cell-homing Scaffold: Its Bioactivity Testing in a Microphysiological Dental Pulp Platform.

In vitro models of the dental pulp microenvironment have been proposed for the assessment of biomaterials, to minimise animal use in operative dentistry. In this study, a scaffold/3-D dental pulp cell culture interface was created in a microchip, under simulated dental pulp pressure, to evaluate the cell-homing potential of a chitosan (CH) scaffold functionalised with calcium aluminate (the 'CHAlCa scaffold'). This microphysiological platform was cultured at a pressure of 15 cm H2O for up to 14 days; cell viability, migration and odontoblastic differentiation were then assessed. The CHAlCa scaffold exhibited intense chemotactic potential, causing cells to migrate from the 3-D culture to its surface, followed by infiltration into the macroporous structure of the scaffold. By contrast, the cells in the presence of the non-functionalised chitosan scaffold showed low cell migration and no cell infiltration. CHAlCa scaffold bioactivity was confirmed in dentin sialophosphoprotein-positive migrating cells, and odontoblastic markers were upregulated in 3-D culture. Finally, in situ mineralised matrix deposition by the cells was confirmed in an Alizarin Red-based assay, in which the CHAlCa and CH scaffolds were adapted to fit within dentin discs. More intense deposition of matrix was observed with the CHAlCa scaffold, as compared to the CH scaffold. In summary, we present an in vitro platform that provides a simple and reproducible model for selecting and developing innovative biomaterials through the assessment of their cell-homing potential. By using this platform, it was shown that the combination of calcium aluminate and chitosan has potential as an inductive biomaterial that can mediate dentin tissue regeneration during cell-homing therapies.

In vitro and in vivo anthelmintic response of the seeds of Amomum subulatum roxb and Vitex negundo / Atividade anti-helmíntica in vitro e in vivo das sementes de Amomum subulatum roxb e Vitex negundo

The current study was designed to check the anthelmintic activities of some local plants. Seeds of Amomum (A.) subulatum and Vitex (V.) negundo in different solvents were subjected to in vitro (adult motility assay; AMA and egg hatch assay; EHA) and in vivo (faecal egg count reduction test; FECRT) anthelmintic activity testing protocols using Haemonchus (H.) contortus as an experimental model. The results of AMA, EHA, and FECRT were statistically analysed through linear regression and Duncan multiple range test. In AMA test, at 50 mg mL-1 concentration, the percent mortality of H. contortus was higher in A. subulatum than V. negundo, whereas, in EHA test, A. subulatum was proven better ovicidal (LC50=14.2 µg mL-1) than V. negundo (LC50= 65.7405 µg mL-1). The FECRT also indicated the better efficacy of A. subulatum than V. negundo against natural infection of gastrointestinal (GI) parasites. The crude powder of plants used in this study showed 29.6% to 57.7% anthelmintic. The reduction rate was found higher for A. subulatum (3 g kg-1) as compared to V. negundo (7 g kg-1). Reagrding efficacy analysis of solvents used for plants extract, ethyl acetate and chloroform were found better in increasing ovicidal activity in adult worms (in vitro testing), whereas, the crude aqueous methanol was found better than the crude powders in in vivo testing. It will be beneficial to document the indigenous knowledge to standard scientific procedures for their validation. This study will help to motivate the farmers to make a better choice of cultivation of the indigenous plants because of their varying efficacies as an alternative preventive approach against the GI parasitic infections.

O presente estudo foi desenhado para verificar as propriedades anti-helmínticas de algumas plantas locais. Sementes de Amomum (A.) subulatum e Vitex (V.) negundo em diferentes solventes foram submetidas à análise de atividade anti-helmíntica in vitro (ensaio de motilidade de adultos; AMA e teste de eclosão de ovos; EHA) e in vivo (teste de redução da contagem de ovos nas fezes; TRCOF), usando o Haemonchus (H.) contortus como modelo experimental no protocolo de teste. Os resultados dos testes AMA, EHA e TRCOF foram analisados ​​estatisticamente por meio de regressão linear e teste de Duncan. No teste AMA, na concentração de 50 mg mL-1, o percentual de mortalidade de H. contortus foi maior com o uso de A. subulatum do que com V. negundo, enquanto, no teste EHA, A. subulatum apresentou maior ação ovicida (LC50=14,2 µg mL- 1) do que V. negundo (LC50= 65,7405 µg mL-1). O TRCOF também indicou a melhor eficácia do uso de A. subulatum do que de V. negundo contra a infecção natural de parasitas gastrointestinais (GI). O extrato bruto seco das plantas utilizadas neste estudo apresentou 29,6% a 57,7% de atividade anti-helmíntica. A taxa de redução observada com o uso de A. subulatum (3 g kg-1) foi maior que com o uso de V. negundo (7 g kg-1). Em relação à análise da eficácia dos solventes utilizados para o extrato de plantas, o acetato de etila e o clorofórmio apresentaram maior ação ovicida em vermes adultos (testes in vitro), enquanto o extrato bruto metanólico aquoso apresentou maior eficácia do que os extratos brutos secos em testes in vivo. Consideramos vantajoso documentar o conhecimento indígena relativos aos procedimentos científicos padronizados, para sua validação. Este estudo irá servir de motivação para que os agricultores façam escolhas melhores referentes ao cultivo das plantas indígenas devido às suas diferentes eficácias comprovadas, servindo como alternativa para a abordagem preventiva contra as infecções parasitárias GI.

Microparticles in the Development and Improvement of Pharmaceutical Formulations: An Analysis of In Vitro and In Vivo Studies.

Microparticulate systems such as microparticles, microspheres, microcapsules or any particle in a micrometer scale (usually of 1-1000 µm) are widely used as drug delivery systems, because they offer higher therapeutic and diagnostic performance compared to conventional drug delivery forms. These systems can be manufactured with many raw materials, especially polymers, most of which have been effective in improving the physicochemical properties and biological activities of active compounds. This review will focus on the in vivo and in vitro application in the last decade (2012 to 2022) of different active pharmaceutical ingredients microencapsulated in polymeric or lipid matrices, the main formulation factors (excipients and techniques) and mostly their biological activities, with the aim of introducing and discussing the potential applicability of microparticulate systems in the pharmaceutical field.

The Surprisingly Positive Effect of Zinc-Phthalocyanines With High Photodynamic Therapy Efficacy of Melanoma Cancer.

Phthalocyanine (Pc) dyes are photoactive molecules that can absorb and emit light in the visible spectrum, especially in the red region of the spectrum, with great potential for biological scopes. For this target, it is important to guarantee a high Pc solubility, and the use of suitable pyridinium units on their structure can be a good strategy to use effective photosensitizers (PSs) for photodynamic therapy (PDT) against cancer cells. Zn(II) phthalocyanines (ZnPcs) conjugated with thiopyridinium units (1-3) were evaluated as PS drugs against B16F10 melanoma cells, and their photophysical, photochemical, and in vitro photobiological properties were determined. The photodynamic efficiency of the tetra- and octa-cationic ZnPcs 1-3 was studied and compared at 1, 2, 5, 10, and 20 µM. The different number of charge units, and the presence/absence of a-F atoms on the Pc structure, contributes for their PDT efficacy. The 3-(4',5'-dimethylthiazol-2'-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays on B16F10 melanoma cells show a moderate to high capacity to be photoinactivated by ZnPcs 1-3 (ZnPc 1 > ZnPc 2 > ZnPc 3). The best PDT conditions were found at a Pc concentration of 20 µM, under red light (λ = 660 ± 20 nm) at an irradiance of 4.5 mW/cm2 for 667 s (light dose of 3 J/cm2). In these conditions, it is noteworthy that the cationic ZnPc 1 shows a promising photoinactivation ratio, reaching the detection limit of the MTT method. Moreover, these results are comparable to the better ones in the literature.

Synergistic effect of oxytetracycline as a combination treatment with Carboplatin on MCF-7 breast cancer cell line / Efeito sinérgico da oxitetraciclina em um tratamento combinado com Carboplatina na linhagem de células cancerígenas pulmonares MCF-7

In breast cancer treatment, chemotherapy resistance is a major problem where many receptive tumors rebound and develop resistance. When provided in combination, cancer drugs are most successful, thus reducing the risk of developing resistant cancer cells. However, the evaluation of combination therapies has increased rapidly in recent years. Consequently, by repurposing old treatments, the discovery of additional medicines that may interact synergistically with chemotherapy is considered a current medical aim through discovering a new cancer medication or therapeutic strategy. The purpose of this research is to increase the anti-cancer activity of carboplatin (CP) by increasing the apoptotic effect of breast cancer cells (MCF-7) during in vitro experiments in combination with oxytetracycline. Our results showed a high synergistic effect between oxytetracycline and carboplatin, MCF-7 representative cell treated with carboplatin with/without different concentrations of oxytetracycline (5% and 10% of IC50). Oxytetracycline, which potentiated the action of carboplatin and/or had notable activity was reported as a single agent. This research demonstrated the synergistic relationship between oxytetracycline and carboplatin in viability assays. Surprisingly, our findings suggest that inhibiting treatment strategies can extend carboplatin's therapeutic window, potentially allowing for cancer therapy.(AU)

No tratamento do câncer de pulmão a resistência à quimioterapia é o maior problema no qual muitos tumores receptivos apresentam um rebote e desenvolvem a resistência. Quando oferecidas em combinações, as drogas anticancerígenas apresentam maior taxa de sucesso, reduzindo assim o risco de desenvolvimento de células cancerígenas resistentes. Contudo, a avaliação das terapias de combinação tem crescido muito rapidamente. Consequentemente, por reaproveitamento de tratamentos antigos, a descoberta de novos medicamentos adicionais que podem interagir sinergicamente com a quimioterapia que é considerada como auxílio médico na corrente busca à descoberta de novas medicações anticancerígenas ou estratégias terapêuticas. O propósito da presente pesquisa é aumentar a atividade anticancerígena da Carboplatina (CP) pelo incremento do efeito apoptótico de células de câncer pulmonar (MCF-7) em experimentos in vitro pela combinação com oxitetraciclina. Os resultados obtidos confirmaram elevado efeito sinérgico entre oxitetraciclina e Carboplatina em células MCF-7 representativas tratadas com Carboplatina, com e sem diferentes concentrações de oxitetraciclina (5% e 10% de IC50). A oxitetracilina que potencializou a ação da Carboplatina e/ou teve uma notável atividade relatada como um agente isolado. A pesquisa demonstrou a relação sinérgica entre oxitetraxiclina e Carboplatina nos ensaios de viabilidade. Surpreendentemente, os resultados obtidos sugeriram que as estratégias de tratamento inibidor podem aplicar um janela terapêutica da Carboplatina com potencial para a terapia do câncer.(AU)

In vitro bacterial probiotic selection from Nannostomus beckfordi, an Amazon ornamental fish / [Seleção in vitro de bactérias probióticas do peixe ornamental Amazônico Nannostomus beckfordi]

This study aimed to isolate and select in vitro bacteria with probiotic potential for the Amazon ornamental fish Nannostomus beckfordi. For isolate, twelve fish underwent surgery procedure to remove their intestinal tract, macerate and then inoculate in the plate petri containing de Man Rugosa Sharped Agar (MRS). After bacterial growth (48 hours at 35ºC), selected strains were inoculated in MRS broth and submitted to resistance test with NaCl (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0%), pH (4, 5, 6, 8 and 9) and bile salts (5% w/v). Inhibition test against pathogenic bacteria Aeromonas hydrophila, Pseudomonas aeroginosa, Streptococcus agalactiae and Aeromonas Jandaei was also performed. Within the isolated strains group (23 strains), only six (S1, S2, S3, S4, S5 and S6) showed probiotic potential. Strains S1 and S6 showed the greater resistance for NaCl (0.5% and 1%) and pH (5 and 6), but only S1 obtained better results to resist the bile salts. Even against pathogenic bacteria, the S1 showed the best results with inhibition halos greater than 9 mm. In the end, this bacterial strain (S1) was identified as Enterococcus faecium 11037CHB. Thus, this is the first report regarding isolated autochthonous bacterium E. faecium with probiotic potential of N. beckfordi.

O objetivo deste estudo foi isolar e selecionar in vitro bactérias com potencial probiótico do peixe ornamental Amazônico Nannostomus beckfordi. Para o isolamento, retirou-se o intestino de 12 espécimes, que foram macerados, homogeneizados e semeados em placa de petri contento Ágar Man Rogosa e Sharpe (MRS). Posteriormente ao crescimento bacteriano (48 horas a 35ºC), as cepas selecionadas foram mantidas em caldo MRS e submetidas a testes de resistência a NaCl (0,5, 1,0, 1,5, 2,0 e 2,5 e 3,0%), pH (4, 5, 6, 8 e 9) e sais biliares (5% p/v). O antagonismo foi realizado frente as bactérias patogênicas Aeromonas hydrophila, Pseudomonas aeroginosa, Streptococcus agalactiae e Aeromonas jandaei. Das cepas isoladas (23 cepas), apenas seis (C1, C2, C3, C4, C5 e C6) apresentaram potencial probiótico. As cepas C1 e C6 tiveram maior resistência (p<0,05) para o NaCl (0,5 e 1%) e pH (5 a 6), na presença de sais biliares somente a C1 teve a melhor resistência de crescimento. Para o antagonismo frente as bactérias patogênicas, a C1 apresentou halo de inibição maior que 9 mm. Sendo esta cepa bactéria (C1) identificada como Enterococcus faecium 11037 CHB. Portanto, este é o primeiro relato do isolamento da bactéria autóctone E. faecium em N. beckfordi com potencial probiótico.

The translational challenge in Chagas disease drug development

Chagas disease is a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. There is an urgent need for safe, effective, and accessible new treatments since the currently approved drugs have serious limitations. Drug development for Chagas disease has historically been hampered by the complexity of the disease, critical knowledge gaps, and lack of coordinated R&D efforts. This review covers some of the translational challenges associated with the progression of new chemical entities from preclinical to clinical phases of development, and discusses how recent technological advances might allow the research community to answer key questions relevant to the disease and to overcome hurdles in R&D for Chagas disease.

Energy values and protein digestibility of soybean milk by-product in pigs based on in vitro assays / Valores energéticos y digestibilidad proteica del subproducto de la leche de soja en cerdos con base en ensayos in vitro / Valores energéticos e digestibilidade protéica do subproduto do leite de soja em suínos com base em ensaios in vitro

Abstract Background: Soybean milk by-product (SMBP) is a potential alternative feed ingredient in swine diets due to its high protein content. However, information on energy and nutritional values of SMBP used as swine feed ingredient is limited. Objective: To estimate energy values and protein digestibility of SMBP in pigs based on in vitro assays. Methods: Four SMBP samples were obtained from 3 soybean milk-producing facilities. In vitro total tract disappearance (IVTTD) and in vitro ileal disappearance (IVID) of dry matter (DM) in the SMBP samples were determined. In vitro ileal disappearance of crude protein was determined by analyzing crude protein content in undigested residues after determining IVID of DM. Digestible and metabolizable energy of SMBP were estimated using gross energy, IVTTD of DM, and prediction equations. Results: Sample 4 had greater IVTTD of DM than that of sample 3 (97.7 vs. 94.4%, p<0.05), whereas IVID of DM in sample 4 was lower compared with sample 1 (53.5 vs. 65.0%, p<0.05). In vitro ileal disappearance of crude protein in sample 2 was greater than that in sample 1 and 3 (92.6 vs. 90.6 and 90.1%; p<0.05). The estimated metabolizable energy of SMBP ranged from 4,311 to 4,619 kcal/kg as-is basis and the value of sample 3 was the least (p<0.05) among SMBP samples. Conclusion: Energy values and protein digestibility should be determined before using SMBP in swine diets.

Resumen Antecedentes: El subproducto de la leche de soja (SMBP) es un ingrediente alimenticio alternativo con uso potencial en dietas porcinas dado su alto contenido de proteína. Sin embargo, la información sobre sus valores energéticos y nutricionales para alimentación de cerdos es muy limitada. Objetivo: Estimar los valores de energía y la digestibilidad de la proteína del SMBP en cerdos con base en ensayos in vitro. Métodos: Se obtuvieron cuatro muestras de SMBP de tres empresas productoras de leche de soja. Se determinaron la desaparición de tracto total in vitro (IVTTD) y la desaparición ileal in vitro (IVID) de la materia seca (DM) en las muestras de SMBP. La desaparición ileal in vitro de proteína cruda se determinó analizando el contenido de proteína cruda en residuos no digeridos después de determinar la IVID de la DM. La energía digestible y metabolizable de SMBP se estimó utilizando la energía bruta, IVTTD de la DM y ecuaciones de predicción. Resultados: La muestra 4 tuvo una mayor IVTTD de la DM que la muestra 3 (97,7 vs. 94,4%, p<0,05), mientras que la IVID de la DM en la muestra 4 fue menor en comparación con la muestra 1 (53,5 vs. 65,0%, p<0,05). La desaparición ileal in vitro de la proteína cruda en la muestra 2 fue mayor que la de las muestras 1 y 3 (92,6 vs. 90,6 y 90,1%; p<0,05). La energía metabolizable estimada de SMBP varió de 4.311 a 4.619 kcal/kg (en base húmeda) y el valor de la muestra 3 fue el menor (p<0.05) entre las muestras de SMBP. Conclusión: Los valores de energía y la digestibilidad de la proteína deben determinarse antes de usar el SMBP en dietas porcinas.

Resumo Antecedentes: O subproduto do leite de soja (SMBP) é um potencial ingrediente alternativo na dieta de suínos, considerando seu alto teor de proteínas. No entanto, as informações sobre os valores energéticos e nutricionais do SMBP usado como ingrediente alimentar para suínos são limitadas. Objetivo: Estimar valores energéticos e digestibilidade protéica do SMBP em suínos com base em ensaios in vitro. Métodos: Foram obtidas quatro amostras de SMBP de três instalações produtores de leite de soja. Foram determinados o desaparecimento total do trato in vitro (IVTTD) e o desaparecimento ileal in vitro (IVID) da matéria seca (DM) nas amostras de SMBP. O desaparecimento ileal in vitro da proteína bruta foi determinado pela análise do conteúdo de proteína bruta em resíduos não digeridos após a determinação da IVID do DM. A energia digerível e metabolizável do SMBP foi estimada usando energia bruta, IVTTD do DM e equações de predição. Resultados: a amostra 4 apresentou maior IVTTD de DM do que a amostra 3 (97,7 vs. 94,4%, p<0,05) enquanto a IVID do DM na amostra 4 foi menor em comparação com a amostra 1 (53,5 vs. 65,0%, p<0,05). O desaparecimento ileal in vitro da proteína bruta na amostra 2 foi superior ao da amostra 1 e 3 (92,6 vs. 90,6 e 90,1%; p<0,05). A energia metabolizável estimada do SMBP variou de 4.311 a 4.619 kcal/kg no estado em que se encontra e o valor da amostra 3 foi o menor (p<0,05) entre as amostras do SMBP. Conclusão: os valores energéticos e a digestibilidade das proteínas devem ser determinados antes do uso do SMBP nas dietas suínas.

Estandarización de un método para la identificación y determinación de contenido antigénico en vacunas contra la hepatitis B mediante el ensayo por inmunoabsorción ligado a enzima (ELISA) / Standardization of identification and determination of antigenic content in hepatitis B vaccines enzyme linked immuno sorbent assay (ELISA) method

Las afecciones causadas por el Virus de la Hepatitis B (VHB) constituyen una de las grandes problemáticas de salud pública a nivel mundial. En la actualidad la principal estrategia de prevención es una vacuna obtenida mediante la tecnología de ADN recombinante a partir de la expresión del gen viral que codifica el antígeno de superficie de la hepatitis B (HBsAg). En Argentina, esta vacuna está incorporada en el Calendario Nacional de Vacunación desde el año 2000, y es deber de la Autoridad Reguladora Nacional (ARN) verificar la calidad, seguridad y eficacia de cada lote liberado al mercado. Considerando que la determinación del contenido antigénico en vacunas representa uno de los ensayos esenciales de control de calidad y que, para ello, es necesario contar con metodologías estandarizadas que permitan obtener resultados reproducibles y confiables, en el Laboratorio de Inmunobiológicos del Instituto Nacional de Medicamentos se estandarizó un método para la identificación y cuantificación del HBsAg en vacunas contra la Hepatitis B empleando un kit comercial de ELISA cuyo uso clínico está previsto para la detección de HBsAg en suero o plasma humano. Para ello, se analizaron dos muestras: una preparación de antígeno HBsAg purificado y una vacuna contra la Hepatitis B ADN recombinante comercial y se evaluaron los parámetros de especificidad, exactitud, repetibilidad, precisión intermedia y linealidad. En todos los casos, se cumplieron con los criterios de aceptación establecidos para cada parámetro, por lo cual se concluye que la metodología analítica es adecuada para la identificación y cuantificación del HBsAg.

Estandarización de un método para la identificación y determinación de contenido antigénico en vacunas contra la hepatitis B mediante el ensayo por inmunoabsorción ligado a enzima (ELISA) / Standardization of identification and determination of antigenic content in hepatitis B vaccines enzyme linked immuno sorbent assay (ELISA) method

Las afecciones causadas por el Virus de la Hepatitis B (VHB) constituyen una de las grandes problemáticas de salud pública a nivel mundial. En la actualidad la principal estrategia de prevención es una vacuna obtenida mediante la tecnología de ADN recombinante a partir de la expresión del gen viral que codifica el antígeno de superficie de la hepatitis B (HBsAg). En Argentina, esta vacuna está incorporada en el Calendario Nacional de Vacunación desde el año 2000, y es deber de la Autoridad Reguladora Nacional (ARN) verificar la calidad, seguridad y eficacia de cada lote liberado al mercado. Considerando que la determinación del contenido antigénico en vacunas representa uno de los ensayos esenciales de control de calidad y que, para ello, es necesario contar con metodologías estandarizadas que permitan obtener resultados reproducibles y confiables, en el Laboratorio de Inmunobiológicos del Instituto Nacional de Medicamentos se estandarizó un método para la identificación y cuantificación del HBsAg en vacunas contra la Hepatitis B empleando un kit comercial de ELISA cuyo uso clínico está previsto para la detección de HBsAg en suero o plasma humano. Para ello, se analizaron dos muestras: una preparación de antígeno HBsAg purificado y una vacuna contra la Hepatitis B ADN recombinante comercial y se evaluaron los parámetros de especificidad, exactitud, repetibilidad, precisión intermedia y linealidad. En todos los casos, se cumplieron con los criterios de aceptación establecidos para cada parámetro, por lo cual se concluye que la metodología analítica es adecuada para la identificación y cuantificación del HBsAg.

Estandarización de un método para la identificación y determinación de contenido antigénico en vacunas contra la hepatitis B mediante el ensayo por inmunoabsorción ligado a enzima (ELISA) / Standardization of identification and determination of antigenic content in hepatitis B vaccines enzyme linked immuno sorbent assay (ELISA) method

Las afecciones causadas por el Virus de la Hepatitis B (VHB) constituyen una de las grandes problemáticas de salud pública a nivel mundial. En la actualidad la principal estrategia de prevención es una vacuna obtenida mediante la tecnología de ADN recombinante a partir de la expresión del gen viral que codifica el antígeno de superficie de la hepatitis B (HBsAg). En Argentina, esta vacuna está incorporada en el Calendario Nacional de Vacunación desde el año 2000, y es deber de la Autoridad Reguladora Nacional (ARN) verificar la calidad, seguridad y eficacia de cada lote liberado al mercado. Considerando que la determinación del contenido antigénico en vacunas representa uno de los ensayos esenciales de control de calidad y que, para ello, es necesario contar con metodologías estandarizadas que permitan obtener resultados reproducibles y confiables, en el Laboratorio de Inmunobiológicos del Instituto Nacional de Medicamentos se estandarizó un método para la identificación y cuantificación del HBsAg en vacunas contra la Hepatitis B empleando un kit comercial de ELISA cuyo uso clínico está previsto para la detección de HBsAg en suero o plasma humano. Para ello, se analizaron dos muestras: una preparación de antígeno HBsAg purificado y una vacuna contra la Hepatitis B ADN recombinante comercial y se evaluaron los parámetros de especificidad, exactitud, repetibilidad, precisión intermedia y linealidad. En todos los casos, se cumplieron con los criterios de aceptación establecidos para cada parámetro, por lo cual se concluye que la metodología analítica es adecuada para la identificación y cuantificación del HBsAg.

In vitro acaricidal activity of different ectoparasiticide classes against Amblyomma sculptum larvae / Atividade acaricida in vitro de diferentes classes de ectoparasiticidas frente a larvas de Amblyomma sculptum

Abstract Zoonoses are major causes of morbidity and mortality worldwide. Among them, Brazilian Spotted Fever (BSF) is an important one that occurs in some regions of South America and can be transmitted by the "star tick" Amblyomma sculptum. Application of acaricides against the larval stage is important as strategy of population control. However, there is still a deficiency of studies on chemical control of A. sculptum and the present work aims to evaluate the in vitro acaricidal activity of cypermethrin, flumethrin, deltamethrin, fipronil, coumaphos and chlorpyrifos against A. sculptum larvae. Bioassays were performed using the larval immersion test method. A discriminatory analysis between the antiparasitic classes most used for tick control was carried out, which made it possible to determine the classes with higher potential for controlling A. sculptum larvae. Our results showed that A. sculptum larvae present highest sensitivity to the synthetic pyrethroid group, followed by the phenylpyrazole, organophosphate and macrocyclic lactone groups. These findings may support studies on improvement of tick control as in animals as in the environment.

Resumo As zoonoses são a maior causa de morbidade de mortalidade no mundo. A Febre Maculosa Brasileira (FMB) é uma importante zoonose que ocorre em algumas regiões da América do Sul e pode ser transmitida pelo "carrapato-estrela" Amblyomma sculptum. A aplicação de acaricidas, frente ao estágio larval, é importante como estratégia no controle da população. No entanto, ainda há uma deficiência de estudos para o controle químico de A. sculptum. Devido à necessidade de mais informações sobre o controle de A. sculptum, o presente trabalho tem como objetivo avaliar a atividade acaricida in vitro de cipermetrina, flumetrina, deltametrina, fipronil, coumafós e clorpirifós frente a larvas de A. sculptum. Os bioensaios foram realizados pelo método Teste de Imersão de Larva. Foi realizada uma análise discriminatória entre as classes antiparasitárias mais utilizadas para controle de carrapatos, possibilitando determinar classes com maior potencial para o controle de larvas de A. sculptum. Os resultados deste trabalho mostraram que as larvas de A. sculptum apresentam maior sensibilidade ao grupo dos piretroides sintéticos, seguido pelos grupos fenilpirazóis, organofosforados e lactonas macrocíclicas. Esses achados poderiam apoiar estudos visando ao controle do carrapato tanto em animais quanto no meio ambiente.

In vitro acaricidal activity of different ectoparasiticide classes against Amblyomma sculptum larvae / Atividade acaricida in vitro de diferentes classes de ectoparasiticidas frente a larvas de Amblyomma sculptum

Zoonoses are major causes of morbidity and mortality worldwide. Among them, Brazilian Spotted Fever (BSF) is an important one that occurs in some regions of South America and can be transmitted by the “star tick” Amblyomma sculptum. Application of acaricides against the larval stage is important as strategy of population control. However, there is still a deficiency of studies on chemical control of A. sculptum and the present work aims to evaluate the in vitro acaricidal activity of cypermethrin, flumethrin, deltamethrin, fipronil, coumaphos and chlorpyrifos against A. sculptum larvae. Bioassays were performed using the larval immersion test method. A discriminatory analysis between the antiparasitic classes most used for tick control was carried out, which made it possible to determine the classes with higher potential for controlling A. sculptum larvae. Our results showed that A. sculptum larvae present highest sensitivity to the synthetic pyrethroid group, followed by the phenylpyrazole, organophosphate and macrocyclic lactone groups. These findings may support studies on improvement of tick control as in animals as in the environment.(AU)

As zoonoses são a maior causa de morbidade de mortalidade no mundo. A Febre Maculosa Brasileira (FMB) é uma importante zoonose que ocorre em algumas regiões da América do Sul e pode ser transmitida pelo “carrapato-estrela” Amblyomma sculptum. A aplicação de acaricidas, frente ao estágio larval, é importante como estratégia no controle da população. No entanto, ainda há uma deficiência de estudos para o controle químico de A. sculptum. Devido à necessidade de mais informações sobre o controle de A. sculptum, o presente trabalho tem como objetivo avaliar a atividade acaricida in vitro de cipermetrina, flumetrina, deltametrina, fipronil, coumafós e clorpirifós frente a larvas de A. sculptum. Os bioensaios foram realizados pelo método Teste de Imersão de Larva. Foi realizada uma análise discriminatória entre as classes antiparasitárias mais utilizadas para controle de carrapatos, possibilitando determinar classes com maior potencial para o controle de larvas de A. sculptum. Os resultados deste trabalho mostraram que as larvas de A. sculptum apresentam maior sensibilidade ao grupo dos piretroides sintéticos, seguido pelos grupos fenilpirazóis, organofosforados e lactonas macrocíclicas. Esses achados poderiam apoiar estudos visando ao controle do carrapato tanto em animais quanto no meio ambiente.(AU)~ipt

Development of a cell-based in vitro assay as a possible alternative for determining bothropic antivenom potency.

Accidents with venomous snakes are a major health hazard in tropical countries. Bothrops genus is responsible for almost 80% of snakebites in Brazil. Immunotherapy is the only approved specific treatment against snake toxins and the production of therapeutic antivenoms requires quality control tests to determine their neutralizing potency. Currently, these controls are performed by in vivo lethality neutralization, however, the inhibition of particular events produced by bothropic venoms such as coagulopathy, hemorrhage, edema or cytotoxic effects are also required. The aim of this work is to develop an in vitro alternative assay for antivenom pre-clinical evaluation. In this sense, we designed a cell viability assay using different amounts (0.2-10 µL/well) of low and high potency anti-bothropic sera, previously classified by the traditional in vivo test, for assessing the antivenom capacity to protect the cells against B. jararaca venom cytotoxicity (5xEC50 = 58.95 µg/mL). We found that high potency sera are more effective in neutralizing B. jararaca venom cytotoxicity when compared to low potency sera, which is in accordance to their pre-determined in vivo potency. Considering sera in vitro inhibitory concentration able to prevent 50% cell death (IC50) and their known in vivo potency, a cut-off point was determined to discriminate low and high potency sera. Our data provide insights for the development of an in vitro method which can determine the anti-bothropic antivenom potency during its production.

Inihibition of mullet (M. liza) brain acetylcholinesterase activity by in vitro polycyclic aromatic hydrocarbon exposure.

Polycyclic aromatic hydrocarbons (PAH) have been reported as acetylcholinesterase (AChE) inibitors, although in vitro studies on PAH effects on AChE activity are scarce and have only been performed using electric eel brain extracts. Thus, this study investigated PAH effects on brain AChE activity in a tropical fish species in Southeastern Brazil, mullet (Mugil liza). Mullet specimens were obtained from Guanabara Bay (N = 20), Rio de Janeiro, Brazil. Brain AChE was extracted and exposed to an environmentally relevant concentration of Pyrene, Chrysene, Phenanthrene, and Naphthalene, and PAH metabolites, 2-Naphthol and 1-OH-Pyrene. AChE activity inhibition was observed, although no difference was observed between high- and low- molecular weight PAH. 2-Naphthol was a less potent AChE inhibitor than Naphthalene, albeit non-significantly. Further studies are required, since only one PAH concentration was used herein. Mullet brain extracts seem to be adequate to assess possible neurotoxic PAH effects on fish AChE.

Viability Assays of PLLA Fibrous Membranes Produced by Rotary Jet Spinning for Application in Tissue Engineering

Abstract Tissue engineering suggests different forms to reconstruct tissues and organs. One of the ways is through the use of polymeric biomaterials such as poly(L-lactic acid) (PLLA). PLLA is a recognized material in tissue engineering due to its characteristics as biocompatibility and bioresorbability. In this work PLLA fibrous membranes were produced by a simple technique known as rotary jet spinning. The rotary jet spinning consists of fibrous membranes production, with fibers of scale nano/micrometric, from a polymeric solution through the centrifugal force generated by the equipment. The membranes formed were subjected to preliminary in vitro assays to verify the cytotoxicity of the membranes made in contact with the cells. Direct cytotoxicity assays were performed through the MTT, AlamarBlue® and Live/Dead® tests, with fibroblastic and osteoblastic cells. The results obtained in this study showed that PLLA membranes produced by rotary jet spinning showed promising results in the 24-hours contact period of the cells with the PLLA fibrous membranes. The information presented in this preliminary study provides criteria to be taken in the future procedures that will be performed with the biomaterial produced, aiming at its improvement.

Immobilizing yeast ß-glucan on zinc-layered hydroxide nanoparticle improves innate immune response in fish leukocytes.

Nanoparticle-based delivery technologies have played a central role in a wide variety of applications, including cell therapy, gene transformation, and cellular delivery of molecular dyes. This work synthesized via ionic exchange a nanoparticle consisting of zinc-layered hydroxychloride coupled with yeast ß-glucan (ZG), whose cellular immune response was evaluated using fish spleen leukocytes. Leukocytes from the marine Pacific red snapper (Lutjanus peru) were stimulated with zinc-layered hydroxychloride (ZHC) coupled with yeast ß-glucan (GLU) and challenged with live Vibrio parahaemolyticus after 24 h. Structural characterization of this yeast glucan by proton nuclear magnetic resonance (NMR) indicated structures containing (1-6)-branched (1-3)-ß-D-glucan. The ZHC and ZG were characterized with X-ray diffraction, infrared spectroscopy, scanning electron microscopy and thermogravimetric analysis. The results of the immunological study showed that ZHC, GLU or ZG were safe for leukocytes because cell viability was higher than 80% compared with DMSO or V. parahaemolyticus exposure. The ZG or GLU treatments enhanced nitric oxide production, superoxide dismutase, catalase and peroxidase activities. Induction of anti- and pro-inflammatory cytokine (IL-1ß, IL-6, IL-8, IL-10, IL-12 and IL-17) genes was more pronounced in ZG or GLU treatments compared to the other groups. Based on the results, ZHC nanoparticles can be used as a delivery carrier of yeast ß-glucan for enhancing immunity in fish and have great potential application in the aquaculture industry.

Eficiência de suco de juçara e manga na veiculação de Lactobacillus rhamnosus GG ao trato gastrointestinal humano simulado por ensaio in vitro / Efficiency of juçara and mango juice in the delivery of Lactobacillus rhamnosus GG to the human gastrointestinal tract simulated by in vitro assay

Este trabalho avaliou a interferência do estresse subletal em pH ácido na sobrevivência de Lactobacillus rhamnosus GG em suco misto de juçara e manga com pH ajustado para 3,0 e 3,5 e a resistência desta bactéria ao trato gastrointestinal simulado in vitro durante 28 dias de armazenamento a 6,0 °C. O estresse ácido previamente aplicado nas células de L. rhamnosus GG não aumentou sua resistência ao trato gastrointestinal simulado in vitro e a bactéria apresentou viabilidade mínima de 3,89 Log UFC/mL após a passagem pela fase entérica II. Os tratamentos utilizados, bem como o tempo de armazenamento, não influenciaram (p>0,05) na viabilidade de L. rhamnosus GG. Portanto, o estresse ácido subletal aplicado não se mostrou eficaz no aumento da sobrevivência da bactéria até 28 dias de armazenamento, mas a mesma apresentou boa sobrevivência no suco em pH ácido, mesmo quando não submetida ao estresse prévio em pH 4,0 por 1 hora a 37 °C.

This work evaluated the interference of sublethal stress at acidic pH in the survival of Lactobacillus rhamnosus GG in mixed jussara and mango juice with pH adjusted to 3,0 and 3,5, and the resistance of this bacterium to the gastrointestinal tract simulated in vitro during 28 days of storage at 6.0 °C. The acid stress previously applied to the cells of L. rhamnosus GG did not increase its resistance to the simulated gastrointestinal tract in vitro and thebacterium had a minimum viability of 3.89 Log CFU/mL after passage through the enteric phase II. The treatments used, as well as the storage time, did not influence (p>0.05) the viability of L. rhamnosus GG. Therefore, the sublethal acid stress applied was not effective in increasing the survival of the bacteria until 28 days of storage, but it presented good survival in the juice at acid pH, even when not submitted to previous stress at pH 4.0 per 1 hour at 37 °C.

Flow-through dynamic microextraction system for automatic in vitro assessment of chyme bioaccessibility in food commodities.

An automatic flow-through dynamic extraction method is proposed for the first time for in vitro exploration, with high temporal resolution, of the transit of the chyme from the gastric to the duodenal compartment using the Versantvoort's fed-state physiologically relevant extraction test. The flow manifold was coupled on-line to an inductively coupled plasma optical emission spectrometer (ICP OES) for real-time elucidation of the bioaccessible elemental fraction of micronutrients (viz., Cu, Fe and Mn) in food commodities across the gastrointestinal tract. The simulated intestinal and bile biofluid (added to the gastric phase) was successively pumped at 1.0 mL min-1 through a large-bore column (maintained at 37.0 ±â€¯2.0 °C) initially loaded with a weighed amount of linseed (250 mg) using a PVDF filter membrane (5.0 µm pore size) for retaining of the solid sample and in-line filtration of the extracts. The lack of bias (trueness) of the on-line gastrointestinal extraction method coupled to ICP OES was confirmed using mass balance validation following microwave assisted digestion of the residual (non-bioaccessible) elemental fraction. Mass balance validation yielded absolute recoveries spanning from 79 to 121% for the overall analytes and samples. On-line dynamic extraction was critically appraised against batch counterparts for both gastric and gastrointestinal compartments. Due to the lack of consensus in the literature regarding the agitation method for batch oral bioaccessibility testing, several extraction approaches (viz., magnetic stirring, end-over-end rotation and orbital shaking) were evaluated. Improved gastric extractability of Fe along with bioaccessible data comparable to the dynamic counterpart based on the continuous displacement of the extraction equilibrium was obtained with batchwise magnetic stirring, which is deemed most appropriate for ascertaining worst-case/maximum bioaccessibility scenarios.