Antibacterial efficacy of novel bismuth-silver nanoparticles synthesis on Staphylococcus aureus and Escherichia coli infection models.

Introduction: The emergence of multi-drug-resistant bacteria is one of the main concerns in the health sector worldwide. The conventional strategies for treatment and prophylaxis against microbial infections include the use of antibiotics. However, these drugs are failing due to the increasing antimicrobial resistance. The unavailability of effective antibiotics highlights the need to discover effective alternatives to combat bacterial infections. One option is the use of metallic nanoparticles, which are toxic to some microorganisms due to their nanometric size. Methods: In this study we (1) synthesize and characterize bismuth and silver nanoparticles, (2) evaluate the antibacterial activity of NPs against Staphylococcus aureus and Escherichia coli in several infection models (in vivo models: infected wound and sepsis and in vitro model: mastitis), and we (3) determine the cytotoxic effect on several cell lines representative of the skin tissue. Results and discussion: We obtained bimetallic nanoparticles of bismuth and silver in a stable aqueous solution from a single reaction by chemical synthesis. These nanoparticles show antibacterial activity on S. aureus and E. coli in vitro without cytotoxic effects on fibroblast, endothelial vascular, and mammary epithelium cell lines. In an infected-wound mice model, antibacterial effect was observed, without effect on in vitro mastitis and sepsis models.

Antitumor efficacy of silver nanoparticles reduced with ß-D-glucose as neoadjuvant therapy to prevent tumor relapse in a mouse model of breast cancer.

Introduction: Neoadjuvant therapy constitutes a valuable modality for diminishing tumor volume prior to surgical resection. Nonetheless, its application encounters limitations in the context of recurrent tumors, which manifest resistance to conventional treatments. Silver nanoparticles (AgNPs) have emerged as a promising alternative for cancer treatment owing to their cytotoxic effects. Methods: Cellular viability was assessed by Alamar blue assay in 4T1 breast cancer cell line. Silver biodistribution was detected by an inductively coupled plasma optical emission spectrometer in an in vivo mice model. For neoadjuvant evaluation, mice were randomized and treated intratumoral with AgNPs-G or intraperitoneally with doxorubicin (DOX) as a control. Recurrence was determined after 170 days by counting lung metastatic nodules (dyed with Bouin solution) with histological confirmation by H&E. Masson's stain, Ki67 immunohistochemistry, and a TUNEL assay were performed in lungs from treated mice. Results: AgNPs-G reduced 4T1 cell viability and in an ex vivo assay the AgNPs-G decreased the tumor cell viability. After intravenous administration of AgNPs-G were detected in different organs. After intratumor administration, AgNPs-G are retained. The AgNPs-G treatment significantly reduced tumor volume before its surgical resection. AgNPs-G reduced the development of lung metastatic nodules and the expression of Ki67. TUNEL assay indicated that AgNPs-G didn't induce apoptosis. Conclusions: We concluded that intratumor administration of AgNPs-G reduced tumor volume before surgical resection, alongside a reduction in lung metastatic nodules, and Ki67 expression. These findings provide valuable insights into the AgNPs-G potential for intratumor and neoadjuvant cancer therapies. However, further research is needed to explore their full potential and optimize their use in clinical settings.

Well-of-the-well (WOW) versus polyester mesh (PM): a comparison of single-embryo culture systems in bovines

Background: Mexico is innovating in the livestock industry through in vitro generation of bovine embryos with technologies such as well-of-the-well (WOW) and polyester mesh (PM) single-embryo culture systems. These techniques allow to maintain embryos in separate areas of a shared culture medium. Objective: To compare the quantity and quality of bovine embryos produced in WOW and PM culture systems versus the conventional (CG) culture system. Methods: In total, 345 embryos fertilized in vitro were evaluated for blastocyst yield in the three culture systems. To count blastocyst cell numbers, 69 embryos in each system were differentially stained for trophectoderm (TE), inner cell mass (ICM), and apoptotic cells. A qPCR gene expression analysis was performed for embryos in all three systems. Results: The WOW, PM and CG systems developed similar amount of blastocysts (41, 35 and 36%, respectively; p>0.05). Blastocysts in all three systems showed adequate amounts of ICM and apoptotic cells. Blastocysts in the PM system showed a greater number of TE cells [63.7 versus 58.6% in the CG system (p0.05). The ATP5B expression was higher in WOW than in PM (p0.05). The TJP3 expression was higher in PM than in WOW and CG (p<0.05). Expression of ID2 and CLDN4 was higher in WOW than in PM and CG (p<0.05). The biplot graphic from Principal Component Analysis (PCA) revealed that CG was located near degenerated embryos, whereas PM was located near arrested embryos, larger ICM and TE, and TJP3 expression. The WOW was located toward blastocysts, morulae, and expression of CLDN4, ID2 and GNAS. Conclusion: Compared with CG, both the PM and WOW systems are good options for culturing single embryos in the bovine model. Moreover, the PCA results suggest that embryos developed in the WOW system have greater capacity for generating blastocysts with increased ability to form TE and ICM layers, which might improve implantation.

Antecedentes: México está innovando en la industria ganadera a través de la generación in vitro de embriones bovinos con tecnologías de cultivo individual como lo son Pozo dentro de Pozo (WOW) y Malla de Poliéster (PM). Estos mantienen los embriones en áreas separadas mientras comparten un mismo medio de cultivo celular. Objetivo: Comparar la cantidad y calidad de embriones bovinos producidos en los sistemas WOW y PM contra el sistema de cultivo convencional en grupo (CG). Métodos: En total se evaluaron 345 embriones fertilizados in vitro para determinar la producción de blastocistos generados en los tres sistemas. Para contar el número de células por blastocisto, 69 embriones en cada sistema se tiñeron diferencialmente para trofectodermo (TE), masa celular interna (ICM) y células apoptóticas. Se realizó un análisis de expresión génica por qPCR de los embriones obtenidos en los tres sistemas. Resultados: Los sistemas WOW, PM y CG desarrollaron similares cantidades de blastocistos (41, 35 y 36%, respectivamente; p>0,05). Los blastocistos en los tres sistemas mostraron cantidades adecuadas de ICM y células apoptóticas. Los blastocistos en el sistema PM mostraron un mayor número de células TE [63,7% versus 58,6% en el sistema CG (p0,05). La expresión de ATP5B fue mayor en WOW que en PM (p<0,05), pero similar a CG (p<0,05). La expresión de TJP3 fue mayor en PM que en WOW y CG (p<0,05). La expresión de ID2 y CLDN4 fue mayor en WOW que en PM y CG (p<0,05). El gráfico de biplot del análisis de componentes principales reveló que CG se encontró cerca de embriones degenerados, mientras que PM se encontró cerca de embriones en arresto, ICM, TE, y TJP3. El WOW se localizó hacia blastocistos, mórulas y la expresión de CLDN4, ID2 y GNAS. Conclusión: En el modelo bovino los sistemas PM y WOW son buenas opciones para cultivar embriones individuales, ya que se obtienen resultados muy similares a los obtenidos con el sistema CG. Además, los resultados de PCA sugieren que los embriones individuales desarrollados en el sistema WOW generan blastocistos con mayor capacidad de formar TE e ICM, lo que podría mejorar su éxito de implantación.

Antecedentes: O México está inovando na indústria pecuária por meio da geração in vitro de embriões bovinos com tecnologias de cultura de embriões individuais, bem como em poço (WOW) e malha de poliéster (PM). Estes mantêm os embriões em áreas separadas, enquanto compartilham o mesmo meio de cultura de células. Objetivo: Comparar a quantidade e a qualidade de embriões bovinos produzidos nos sistemas de cultura WOW e PM com o sistema convencional de cultura em grupo (CG). Métodos: No total, 345 embriões fertilizados in vitro foram avaliados para determinar a produção de blastocistos gerados nos três sistemas. O número de células por blatocisto foi contado, 69 embriões em cada sistema foram diferencialmente corados para trofectoderme (TE), massa celular interna (ICM) e células apoptóticas. Uma análise de expressão gênica qPCR foi realizada para os embriões obtidos nos três sistemas. Resultados: Os sistemas WOW, PM e CG desenvolveram quantidades semelhantes de blastocistos (41, 35 e 36%, respectivamente; p>0,05). Os blastocistos nos três sistemas mostraram quantidades adequadas de ICM e células apoptóticas. Os blastocistos no sistema PM mostraram um número maior de células TE [63,7 versus 58,6% no sistema CG (p0,05). A expressão de ATP5B foi maior no WOW do que no PM (p<0,05), mas semelhante ao GC (p<0,05). A expressão de TJP3 foi maior no PM do que no WOW e CG (p<0,05). A expressão de ID2 e CLDN4 foi maior no WOW do que no PM e CG (p<0,05). O gráfico biplot da análise de componentes principais revelou que CG foi encontrado próximo a embriões degenerados, enquanto PM foi encontrado próximo a embriões presos, ICM, TE e TJP3. WOW foi encontrado para ter blastocistos, mórulas e a expressão de CLDN4, ID2 e GNAS. Conclusão: Em comparação com o CG, os sistemas PM e WOW são boas opções para a cultura de embriões individuais no modelo bovino. Além disso, os resultados da PCA sugerem que embriões individuais desenvolvidos no sistema WOW têm maior capacidade de desenvolver blastocistos com maior capacidade de formar as camadas TE e ICM, o que poderia melhorar seu sucesso de implantação.