Complementary imaging of nanoclusters interacting with mitochondria via stimulated emission depletion and scanning transmission electron microscopy.

The emerging stress caused by nanomaterials in the environment is of great concern because they can have toxic effects on organisms. However, thorough study of the interactions between cells and diverse nanoparticles (NPs) using a unified approach is challenging. Here, we present a novel approach combining stimulated emission depletion (STED) microscopy and scanning transmission electron microscopy (STEM) for quantitative assessment, real-time tracking, and in situ imaging of the intracellular behavior of gold-silver nanoclusters (AuAgNCs), based on their fluorescence and electron properties. The results revealed an aggregated state of AuAgNCs within the mitochondria and an increase in sulfur content in AuAgNCs, presumably owing to their reaction with thiol-containing molecules inside the mitochondria. Moreover, AuAgNCs (100 µg/mL) induced a 75% decline in mitochondrial membrane potential and a 12-fold increase of mitochondrial reactive oxygen species in comparison to control. This mitochondrial damage may be triggered by the reaction of AuAgNCs with thiol, which provides direct imaging evidence for uncovering the action mechanism of AuAgNCs on the mitochondria. The proposed dual-imaging strategy using STED and STEM is a potential tool to offer valuable insights into cytotoxicity between subcellular structures and diverse NPs, and can serve as a key strategy for nanomaterial biosafety assessment.

Distribution Analysis of Iron and Copper by STEM-EDX Spectroscopy of Hemosiderin Particles in the Liver of Rats Overloaded With Iron.

BACKGROUND/AIM: Our recent studies have indicated that trace copper co-existed with iron in hemosiderin particles of human genetic iron overload. To understand this phenomenon, we analyzed hemosiderin particles in iron-overloaded rat liver by using scanning transmission electron microscopy - energy-dispersive X-ray (STEM-EDX) spectroscopy. MATERIALS AND METHODS: Samples for STEM-EDX spectroscopy were prepared from the liver of rats administered an intraperitoneal injection of dextran iron. RESULTS: The micro-domain analysis with STEM-EDX spectroscopy showed that dense bodies contained high levels of iron and trace copper. Quantitative analysis of copper levels in the liver specimen using atomic spectrophotometry showed that copper concentration in the liver was not increased by iron overload. These findings suggest that the overload of iron induced distribution of trace copper to hemosiderin particles without changing cellular copper levels. CONCLUSION: Co-existence of copper with iron was observed in hemosiderin particles of the liver of an experimental model of iron overload, suggesting that iron overload induced distribution of trace copper into hemosiderin particles.

An introduction to scanning transmission electron microscopy for the study of protozoans.

Since its inception in the 1930s, transmission electron microscopy (TEM) has been a powerful method to explore the cellular structure of parasites. TEM usually requires samples of <100 nm thick and with protozoans being larger than 1 µm, their study requires resin embedding and ultrathin sectioning. During the past decade, several new methods have been developed to improve, facilitate, and speed up the structural characterisation of biological samples, offering new imaging modalities for the study of protozoans. In particular, scanning transmission electron microscopy (STEM) can be used to observe sample sections as thick as 1 µm thus becoming an alternative to conventional TEM. STEM can also be performed under cryogenic conditions in combination with cryo-electron tomography providing access to the study of thicker samples in their native hydrated states in 3D. This method, called cryo-scanning transmission electron tomography (cryo-STET), was first developed in 2014. This review presents the basic concepts and benefits of STEM methods and provides examples to illustrate the potential for new insights into the structure and ultrastructure of protozoans.

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.

Caracterização de cubossomos não-iônicos em presença de proteínas modelo: uma abordagem estrutural e funcional / Characterization of non-ionic cubosomes in the presence of model pro­teins: a structural and functional approach

Uma área de pesquisa que vem ganhando muita atenção nos últimos anos é a nanome­dicina, com especial atenção para os sistemas com entrega controlada de fármacos, ou drug delivery. Dentre as diversas nanopartículas utilizadas para este fim, destacam-se os sistemas formados por lipídeos e polímeros, como por exemplo os lipossomos e os cubossomos. Neste trabalho, é estudada a influência estrutural da lisozima e da curcumina, proteínas modelo. A lisozima é uma enzima antimicrobiana produzida por animais e que faz parte do sistema imunológico. Ela é uma hidrolase glicosídica que catalisa a hidrólise dos componentes da parede celular de bactérias gram-positivas. Esta hidrólise, por sua vez, compromete a integridade das paredes celulares, causando a lise (e como consequência a morte) das bactérias. Curcumina é um composto cristalino de cor amarelada brilhante, encontrada no caule da Curcuma longa (ou açafrão), que tem sido utilizada como corante ou até mesmo como aditivo alimentar. Este composto tem sido uma grande aposta no tratamento de doenças crônicas como inflamação, artrite, síndrome metabólica, doença hepática, obesidade, doenças neurodegenerativas e principalmente canceres, sendo também utilizada em estudos como potencial agente antibacteriano. O principal objetivo deste trabalho é construir sistemas nanoestruturados com potencial de atuarem como sistemas antimicrobianos, com a liberação controlada de ambos dos fármacos. Estes sistemas são compostos por cubossomos de fitantriol (PHY) em ausência e presença da lisozima, da curcumina e de suas combinações, a fim de analisar ação antimicrobiana conjunta da lisozima e da curcumina. As técnicas biofísicas utilizadas para caracterizar essas partículas são SAXS (espalhamento de raios-X em baixos ângulos), DLS (espalhamento dinâmico de luz), Cryo-TEM (criomicroscopia eletrônica de transmissão) e NTA (análise de rastreamento de nanopartículas). Foi possível verificar que as formulações lipídicas são eficazes na formação de estruturas cúbicas com estabilidade desejável. As nanopartículas cúbicas demonstraram alta capacidade de encapsulação da lisozima e da curcumina. A cinética de liberação desses medicamentos mostrou-se promissora, sugerindo que a encapsulação dos fármacos é eficaz, bem como a liberação controlada e direcionada. Duas linhagens de bactérias foram estudadas, sendo que a E. coli, não sofreu nenhum dano citotóxico, enquanto a Bacillus subtilis sim. Tal resultado indica o potencial antimicrobiano do sistema para alguns tipos de bactérias

An area of research that has gained significant attention in recent years is nanomedicine, with a particular focus on drug delivery systems. Among the various nanoparticles used for this purpose, lipid and polymer-based systems, such as liposomes and cubosomes stand out. This study investigate the structural influence of encapsulating lysozyme and curcumin, model compounds. Lysozyme is an antimicrobial enzyme produced by animals and is part of the immune system. It is a glycosidic hydrolase that catalyzes the hydrolysis of components in the cell walls of gram-positive bacteria. This hydrolysis compromises the integrity of cell walls, leading to the lysis (and consequently the death) of bacteria. Curcumin is a bright yellow crystalline compound found in the stem of Curcuma longa (or turmeric), commonly used as a dye or even as a food additive. It has been a significant focus in the treatment of chronic diseases such as inflammation, arthritis, metabolic syndrome, liver disease, obesity, neurodegenerative diseases, and especially cancers. It is also studied as a potential antibacterial agent. The main objective of this study is to construct nanostructured systems with the potential to act as antimicrobial agents, with controlled release of both drugs. These systems consist of phytantriol (PHY) cubosomes in the absence and presence of lysozyme, curcumin, and their combinations to analyze the joint antimicrobial action of lysozyme and curcumin. Biophysical techniques used for characterization include Small-Angle X-ray Scattering (SAXS), Dynamic Light Scattering (DLS), Cryo-Transmission Electron Microscopy (Cryo-TEM), and Nanoparticle Tracking Analysis (NTA). It was observed that lipid formulations are effective in forming cubic structures with desirable stability. Cubic nanoparticles have demonstrated a high encapsulation capacity for lysozyme and curcumin. The release kinetics of these drugs have shown promise, suggesting that drug encapsulation is effective, as well as their controlled and targeted release. Two bacterial strains were studied, with E. coli showing no cytotoxic damage, while Bacillus subtilis did. This result indicates the antimicrobial potential of the system against types of bacteria

Considérations relatives à la mise en œuvre et à la gestion de la recherche des contacts de cas de maladie à coronavirus 2019 (COVID 19) dans la Région des Amériques, 5 août 2021

Cette publication de l’Organisation panaméricaine de la Santé (OPS) est une version mise à jour de la publication de juin 2020 intitulée Considérations pour la mise en œuvre et la gestion de la recherche des contacts pour la maladie à coronavirus 2019 (COVID-19) dans la Région des Amériques. Elle est destinée à compléter les directives provisoires de l’Organisation mondiale de la Santé (OMS) sur la recherche des contacts dans le contexte de la COVID-19. La publication comprend des lignes directrices pour la recherche des contacts vaccinés et des voyageurs internationaux, ainsi que dans les milieux de transmission communautaire. Elle comprend également les définitions mises à jour des cas, des contacts et de la transmission communautaire publiées par l’OMS. Elle vise à fournir des orientations et des recommandations opérationnelles pour la mise en œuvre de la recherche des contacts pour la COVID-19 dans la Région des Amériques et sera mise à jour à mesure que les connaissances actuelles sur la COVID-19 évolueront. Les publics cibles de cette publication sont les autorités sanitaires nationales, les professionnels de la santé publique et d’autres responsables impliqués dans l’élaboration et la mise en œuvre de politiques et de procédures opérationnelles normalisées concernant les activités de recherche des contacts dans la Région.

Considerações para a implementação e gestão de rastreamento de contatos para a doença pelo coronavírus 2019 (COVID-19) na Região das Américas, 5 de agosto de 2021

Esta publicação da Organização Pan-Americana da Saúde (OPAS) é uma versão atualizada do documento Considerações para a implementação e gerenciamento de rastreamento de contatos para a doença causada pelo novo coronavírus (COVID-19) na Região das Américas, de junho de 2020, cujo objetivo é complementar a orientação provisória da Organização Mundial da Saúde (OMS) sobre o rastreamento de contatos no contexto da COVID-19. A presente publicação inclui orientações para o rastreamento de contatos entre contatos vacinados e viajantes internacionais e em ambientes com transmissão comunitária. Ela também inclui as definições atualizadas de casos, contatos e transmissão comunitária publicadas pela OMS. Busca fornecer orientações e recomendações operacionais para implementar o rastreamento de contatos de COVID-19 nas Américas. Ela será atualizada conforme o conhecimento atual sobre a COVID-19 evolua. O público-alvo desta publicação são autoridades sanitárias nacionais, profissionais de saúde pública e outros funcionários envolvidos na elaboração e implantação de políticas e procedimentos operacionais padrão relacionados a operações de rastreamento de contatos nas Américas.

Consideraciones sobre la ejecución y el manejo del rastreo de contactos para la enfermedad por coronavirus del 2019 (COVID-19) en la Región de las Américas, 5 de agosto del 2021

Esta publicación de la Organización Panamericana de la Salud (OPS) es una versión actualizada del documento de junio del 2020 titulado Consideraciones sobre la ejecución y el manejo del rastreo de contactos para la enfermedad por coronavirus del 2019 (COVID-19) en la Región de las Américas, cuyo propósito es complementar las orientaciones provisionales proporcionadas por la Organización Mundial de la Salud (OMS) sobre el rastreo de contactos en el contexto de la COVID-19. La presente publicación incluye orientación sobre el rastreo de contactos en los contactos vacunados y viajeros internacionales, así como en los entornos en los que hay transmisión comunitaria. También incluye las definiciones actualizadas de “caso”, “contacto” y “transmisión comunitaria” que ha publicado la OMS. El objetivo del presente documento es brindar orientación y recomendaciones operativas que permitan realizar el rastreo de contactos de COVID-19 en la Región de las Américas. El documento se actualizará conforme se disponga de información nueva sobre la COVID-19. Esta publicación está dirigida a las autoridades nacionales de salud, los profesionales de la salud pública y otros funcionarios que formulan y ejecutan políticas y procedimientos normalizados de trabajo relacionados con las operaciones de rastreo de contactos en la Región.

Tetradenia riparia leaves, flower buds, and stem essential oils to control of Aedes aegypti larvae

Abstract Tetradenia riparia (Hochst.) Codd (Lamiaceae) is a species native to the African continent and used as an insect repellent. The objective of the study was to evaluate the larvicidal potential of essential oils (EOs) from the leaves, flower buds, and stem of T. riparia, collected in winter against Aedes aegypti larvae. The EOs were extracted by hydrodistillation (3 h) and identified by GC/MS. The EOs were tested against larvae of A. aegypti at concentrations ranging from 12500 to 1.5 µg/mL for 24 h. The insecticide activity was evaluated by probit analysis, and the anticholinesterase activity was determined by bioautographic method. The results of the class projection indicated sesquiterpenes as the majority class, corresponding to 60.66% (leaves), 64.70% (flower buds) and 83.99% (stem), and the bioassays on A. aegypti larvae indicated LC50 of 1590, 675 and 665 µg/mL, respectively. The anticholinesterase activity indicated that the EO of the leaves inhibited the enzyme at a concentration of 780 µg/mL, and those from the flower buds and stem inhibited up to 1560 µg/mL. The results indicated weak activity of essential oils against A. aegypti larvae.

Essential Oil from the Stem Bark of Casuarina equisetifolia Exerts Anti-inflammatory and Anti-nociceptive Activities in Rats

Abstract Herein the chemical constituents and the anti-pain properties of the essential oil from the stem bark of Casuarina equisetifolia L. (Casuarinaceae) grown in Nigeria were evaluated. The essential oil was obtained by hydrodistillation method in an all glass Clevenger-type apparatus, and characterized by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The hot plate method was used to determine the anti-nociceptive property whereas the anti-inflammatory activity was evaluated by carrageenan-induced and formalin experimental models. The pale-yellow essential oil was obtained in yield of 0.21% (v/w), calculated on a dry weight basis. The main constituents of the essential oil were methyl salicylate (30.4%), a-zingiberene (15.5%), (E)-anethole (9.5%), b-bisabolene (8.6%), b- sesquiphellandrene (6.9%), and ar-curcumene (6.2%). In the anti-nociceptive study, the rate of inhibition increases as the doses of essential oil increases with optimum activity at the 30th and 60th min for all tested doses. The essential oil displayed anti-nociceptive activity independently of reaction time at the highest tested dose (200 mg/kg). The essential oil of C. equisetifolia moderately reduced pain responses in early and late phases of the formalin test. The oil inhibited the paw licking in the neurogenic phase (60-63%) compared to the late phase of the formalin test. The carrageenan- induced oedema model revealed the suppression of inflammatory mediators within the 1st - 3rd h. Thus, C. equisetifolia essential oil displayed both anti-nociceptive and anti-inflammatory activities independent of the dose tested. The anti-inflammatory and anti-nociceptive activities of C. equisetifolia essential oil are herein reported for the first time

Associação da imunoexpressão das proteínas Ecaderina, SHH e GLI-1 com parâmetros clinicopatológicos em Carcinoma Epidermóide de Língua Oral / Association of immunoexpression of Ecadherin, SHH and GLI-1 proteins with clinicopathological parameters in Oral Tongue Squamous Cell Carcinoma

O potencial de invasão do carcinoma epidermoide requer modifcações fenotípicas nas células parenquimatosas de forma que essas adquiram capacidade de sobreviver e invadir o microambiente tumoral. Esse processo de modificação fenotípica é denominado de transição epitélio-mesenquimal (TEM), cujo as células epiteliais perdem parte de suas características e adquirem outras inerentes às células mesenquimais, de forma controlada por diversos fatores de transcrição indutores destas alterações, conferindo além das habilidades citadas, características de célula tronco, de resistência ao tratamento antineoplásico e angiogênese. O objetivo do presente estudo foi investigar associações da expressão imunoistoquímica das proteínas E-caderina, Shh e Gli-1, sinalizadoras da TEM, com caraterísticas clinicopatológicas de carcinomas epidermoides de língua oral (CELO). A imunoexpressão dessas proteínas foi analisada em 42 casos de CELO, de forma semiquantitativa, nas células neoplásicas do front de invasão tumoral e nos brotamentos tumorais. Os CELOs foram classificados como de baixa e alta expressão proteíca. As gradações de Almangush et al. (2015) e de Boxberg et al. (2017) mostraram categorização semelhante para os casos de CELOs, todavia, a gradação de Almangush et al. (2015) apresentou melhor associação com os parâmetros clínicos, destacando o tamanho do tumor (p=0,013) e o desfecho de óbito (p<0,01). A análise imunoistoquímica revelou predomínio de baixa expressão membranar da E-caderina, apresentando associação significativa com o comprometimento linfonodal (p=0,042). A expressão do Shh foi bem variável e não mostrou associações significativas. A expressão do Gli-1 foi predominantemente alta, mostrando relações significativas com parâmetros clinicopatológicos, como comprometimento linfonodal (p=0,024), estágio clínico do tumor (p=0,016), profundidade de invasão (p=0,015), atividade de brotamentos tumorais (p=0,033), menor tamanho do ninho tumoral (p=0,020) e o grau de diferenciação (p=0,033), sendo estes quatro últimos associados com os brotamentos tumorais. A análise estatística evidenciou ausência de associações significativas entre as variáveis imunoistoquímicas e indicadores de prognóstico do CELO. Os resultados deste estudo indicam que os sistemas de gradação morfológica analisados mostraram-se eficazes na identificação de casos de CELOs mais agressivos, com maior destaque para o proposto por Almangush et al (2015) e, em relação aos achados imunoistoquímicos, os resultados sugerem que a menor expressão membranar da E-caderina e a alta expressão nuclear/citoplasmática de Gli-1 associaram-se ao parâmetro clínico de pior prognóstico, referente ao comprometimento nodal. Diante do modelo do estudo, não se observou associação da imunoexpressão das proteínas estudadas com a sobrevida dos pacientes (AU).

The potential for squamous cell carcinoma invasion requires phenotypic modifications in the parenchymal cells so that they acquire the ability to survive and invade the tumor microenvironment. This process of phenotypic modification is called epithelialmesenchymal transition (EMT), which is crucial for the acquisition of this aggressive malignant phenotype. In this process, the epithelial cells lose part of their characteristics and acquire others inherent to the mesenchymal cells, in a controlled manner, inducing by various transcription factors, conferring, in addition to the aforementioned abilities, stem cell characteristics, resistance to anti-neoplastic treatment and angiogenesis. The aim of the present study was to investigate associations between the immunohistochemical expression of E-cadherin, Shh e, Gli-1 proteins, signaling TEM, with clinicopathological characteristics of oral tongue squamous cell carcinoma (OTSCC). The immunoexpression of these proteins was analyzed in 42 cases of OTSCC, in a semiquantitative way, in the neoplastic cells of the tumor invasion front and in the cells that make up the tumor budding. OTSCCs were classified as low and high protein expression. Aiming at the association of immunohistochemical findings with clinicopathological variables and survival rates, cases were classified into low expression and high expression categories. Initially, statistical differences between the histopathological gradations of malignancy by Almangush et al. (2015) and that of Boxberg et al. (2017) regarding clinical parameters. Both, the gradations showed similar categorization for OTSCC cases, were able to categorize the tumors, however, the gradation by Almangush et al. (2015) showed a better association with clinical parameters, highlighting tumor size (p=0.013) and the outcome of death (p<0.01). The immunohistochemical analysis revealed a predominance of low membrane expression of E-cadherin, with a statistically significant association with lymph node involvement (p=0.042). The expression of Shh was quite variable and had no statistically significant associations. Gli-1 had a prevalence of high expression, showing significant relationships with clinicopathological parameters, such as the occurrence of lymph node involvement (p=0.024), clinical stage of the tumor (p=0.016), depth of invasion (p=0.015), activity of tumor budding (p=0.033), smaller size of the tumor nest (p=0.020) and degree of differentiation (p=0.033), the last four being associated with tumor budding. Some correlations between markers were found, such as the positive correlation between the cytoplasmic expression of E-cadherin with Shh (p=0.030) and the immunoexpression of Gli-1 in the cytoplasm/nucleus with Shh (p=0.041). Statistical analysis evidenced the absence of significant associations between immunohistochemical variables and OTSCC prognostic indicators. The findings of this study suggest the expression pattern of E-cadherin, Shh and Gli-1 in OTSCC, in addition to indicating a better clinicopathological association with the malignancy gradation of Almangush et al. (2015). However, the expression of these biomarkers may not be related to patient survival. In addition, no significant differences were observed between the expression of the proteins studied in tumor budding when other cells in the invasion front were evaluated, suggesting a similar cell phenotype for both. The results of this study indicate that the analyzed morphological grading systems proved to be effective in identifying cases of more aggressive OTSCC, with greater emphasis on the one proposed by Almangush et al (2015) and, in relation to the immunohistochemical findings, the results suggest that the lower membrane expression of E-cadherin and the high nuclear/cytoplasmic expression of Gli-1 were associated with the clinical parameter of worse prognosis (AU).

Evaluación preliminar de la actividad de Ageratina havanensis contra virus dengue 2 / Preliminary evaluation of the activity of Ageratina havanensis against the dengue 2 virus

. Introducción: El dengue es la enfermedad viral transmitida por mosquitos de más rápida propagación en el mundo. A pesar de la alta incidencia de la enfermedad no existe tratamiento antiviral efectivo ni vacuna aprobada para su uso contra esta infección. La planta Ageratina havanensis ha sido ampliamente utilizada por nuestra cultura popular y en otros países debido a sus diversas propiedades biológicas. Objetivo: Evaluar la actividad antiviral de cuatro extractos provenientes de Ageratina havanensis y dos flavonoides aislados de dicha planta frente al virus dengue 2. Métodos: La pesquisa primaria de actividad antiviral de cada extracto y flavonoide se realizó mediante el ensayo de detección de la productividad vírica, y se evaluó la acción virucida de los extractos etanólico de tallo y butanólico de hoja. Resultados: Todos los extractos inhibieron la replicación viral al evidenciarse disminución del número de placas de lisis, sin embargo, no se evidenció disminución del título infectivo viral en el ensayo virucida. El tratamiento con la sakuranetina mostró valores de inhibición de la productividad viral entre 61-91 por ciento, y para la 7-metoxiaromadendrina se registraron valores de reducción viral entre 64-86 por ciento. Conclusiones: Los extractos y flavonoides aislados de Ageratina havanensis mostraron acción antiviral. Los extractos etanólico de tallo y butanólico de hojas no poseen acción virucida sobre la cepa viral empleada. El presente trabajo constituye el primer informe respecto a la evaluación de extractos y compuestos aislados de A. havanensis frente al virus dengue(AU)

Introduction: Dengue is the fastest spreading mosquito-borne viral disease worldwide. Despite its high incidence, no effective antiviral treatment or vaccine has been approved for use against this infection. The plant Ageratina havanensis has been widely used in our folk culture and in other countries due to its various biological properties. Objective: Evaluate the antiviral activity of four extracts from Ageratina havanensis and two flavonoids isolated from that plant against the dengue 2 virus. Methods: Primary screening of the antiviral activity of each extract and flavonoid was conducted by viral productivity detection assay, and an evaluation was carried out of the virucidal action of the stem ethanolic extract and the leaf butanolic extract. Results: All the extracts inhibited viral replication by a reduction in the number of lysis plates. However, no evidence was found of a reduced viral infective titer in the virucidal assay. Treatment with sakuranetin achieved viral productivity inhibition values of 61 percent-91 percent, whereas 7-methoxyaromadendrin obtained viral reduction values of 64 percent-86 percent Conclusions: The extracts and flavonoids isolated from Ageratina havanensis displayed antiviral activity. The stem ethanolic extract and the leaf butanolic extract do not have a virucidal action against the viral strain used. The paper is the first report about the effect of extracts and compounds isolated from A. havanensis against the dengue virus(AU)

Trasplante de progenitores hematopoyéticos alogénico haploidéntico en aplasia medular, reporte del primer caso en Cuba / Allogenic hematopoietic stem-cell transplantation in marrow aplasia: the first case report in cuba

Introducción: La aplasia medular adquirida grave es una enfermedad hematológica infrecuente caracterizada por una disminución o ausencia de precursores hematopoyéticos en la médula ósea, lo cual se expresa con distintos grados de citopenias. Varios factores, infecciosos o no, pueden incidir en su origen. Su manejo es complejo y puede incluir tratamiento inmunosupresor y trasplante de progenitores hematopoyéticos alogénico. Objetivo: Demostrar la utilidad de la realización del trasplante de progenitores hematopoyéticos alogénico haploidéntico en pacientes con aplasia medular grave. Caso clínico: Paciente masculino de 21 años de edad, con antecedentes de salud, que en octubre del 2018 debutó con íctero, pancitopenia, lesiones purpúrico hemorrágicas en piel y mucosas, en el curso de una hepatitis aguda seronegativa. La biopsia de médula ósea mostró aplasia medular severa. Se inició tratamiento inmunosupresor con globulina antitimocίtica, ciclosporina A y metilprednisolona. Al cabo de los 6 meses mantenía trombocitopenia severa con necesidades transfusionales y en octubre de 2019 se decide realizar trasplante de progenitores hematopoyéticos alogénico con donante haploidéntico y empleando como tratamiento acondicionante globulina antitimocίtica, fludarabina, ciclofosfamida y bajas dosis de irradiación corporal total. En evaluación clίnica de julio de 2020 (dίa + 280 del trasplante) el paciente estaba asintomático y con parámetros hematológicos normales. Conclusiones: Se demostró que el trasplante de progenitores hematopoyéticos alogénico haploidéntico es un proceder realizable y útil en pacientes con aplasia medular grave, lo cual corrobora el beneficio clínico que puede aportar su ejecución en pacientes con esta enfermedad(AU)

Introduction: Acquired severe marrow aplasia is a rare hematological disease characterized by decrease or absence of hematopoietic precursors in bone marrow, which is expressed with different degrees of cytopenias. Several factors, infectious or not, can influence its origin. Its management is complex and may include immunosuppressive treatment and allogeneic hematopoietic stem-cell transplantation. Objective: To demonstrate the usefulness of performing haploidentical allogeneic hematopoietic stem-cell transplantation in patients with severe medullary aplasia. Clinical case: A 21-year-old male patient, with medical history, who first presented, in October 2018, with icterus, pancytopenia, as well as purpuric hemorrhagic lesions on the skin and mucosa, in the course of acute seronegative hepatitis. The bone marrow biopsy showed severe marrow aplasia. Immunosuppressive treatment was started with antithymocytic globulin, cyclosporine A, and methylprednisolone. After six months, he maintained severe thrombocytopenia under transfusion requirements and, in October 2019, the decision was to perform allogeneic hematopoietic stem-cell transplantation with a haploidentical donor and using antithymocyte globulin, fludarabine, cyclophosphamide, and low doses of total body irradiation as conditioning treatment. In the clinical assessment carried out in July 2020 (day +280 after transplantation), the patient was asymptomatic and with normal hematological parameters. Conclusions: Transplantation of haploidentic allogeneic hematopoietic progenitors was shown to be a feasible and useful procedure in patients with severe marrow aplasia, which corroborates the clinical benefit that its execution can bring in patients with this disease(AU)

Influence of Meloidogyne incognita race 1 on the development of clones of Coffea canephora, variety "Jequitibá Incaper 8122" / Influência de Meloidogyne incognita raça 1 no desenvolvimento de clones de Coffea canephora, variedade "Jequitibá Incaper 8122"

Root-knot nematode is one of the most important phytosanitary problems for Conilon coffee, as it reduces productivity and is difficult to handle. We aimed at studying the infectivity and damage caused by M. incognita race 1 in the "Jequitibá Incaper 8122" intermediate maturity coffee variety. The experiment was conducted in a greenhouse, in completely randomized design, with five replicates. The clones composing the variety "Jequitibá Incaper 8122" were inoculated with 2,000 eggs + second-stage juveniles of M. incognita race 1. Uninoculated plants were the control. Evaluations were performed 180 days after inoculation, considering the plant height (H), stem diameter (SD), number of leaves (NOL), leaf area (LA), number of plagiotropic branches (NPB), number of nodes (NN), chlorophyll content (CHLO), shoot dry matter (SDM), root fresh matter (RFM), final population (FNP), and reproduction factor (NRF). The nematode reduced NOL in clones 208 and 209, NRF in clones 201, 203, 207 and 208, NN in clones 203, 207, 208 and 209, CHLO in clones 201, 204, 206, 207 and 209, SDM in clones 201, 203, 204 and 205 and RFM in clones 205 and 207. M. incognita race 1 FNP and NRF were larger in clones 208, 201, 207 and 203. Clone 202 had FNP and NRF equal to zero, being immune to the nematode. Clone 206 presented the lowest NRF value among clones parasitized by M. incognita.(AU)

O nematoide-das-galhas é um dos mais importantes problemas fitossanitários para o cafeeiro conilon, por reduzir a produtividade e ser de difícil manejo. Objetivou-se estudar a infectividade e os danos causados por M. incognita raça 1 na variedade de café conilon de maturação intermediária "Jequitibá Incaper 8122". O experimento foi conduzido em casa de vegetação, em DIC, com cinco repetições. Os clones que compõem a variedade "Jequitibá Incaper 8122" foram inoculados com 2.000 ovos + juvenis de segundo estádio de M. incognita raça 1. Plantas não inoculadas constituíram a testemunha. As avaliações foram realizadas 180 dias após a inoculação, sendo avaliados: altura da planta (ALT), diâmetro do caule (DCA), número de folhas (NFO), área foliar (AFO), número de ramos plagiotrópicos (NRP), número de nós (NN), teor de clorofila (CLO), massa seca da parte aérea (MSA), matéria fresca da raiz (MFR), população final (PFN) e fator de reprodução (FRE). O nematoide reduziu o NFO nos clones 208 e 209, NRP nos clones 201, 203, 207 e 208, NN nos clones 203, 207, 208 e 209, CLO nos clones 201, 204, 206, 207 e 209, MSA nos clones 201, 203, 204 e 205 e MFR nos clones 205 e 207. PFN e FRE de M. incognita raça 1 foram maiores nos clones 208, 201, 207 e 203; o clone 202 teve a PFN e a FRE igual a zero, apresentando-se imune ao nematoide. O clone 206 apresentou o menor valor de FRE entre os clones parasitados por M. incognita.(AU)

Phytochemical and morpho-anatomical study of the vegetative organs of Psychotria fractistipula L. B.Sm., R.M. Klein & Delprete (Rubiaceae)

Psychotria fractistipula L.B.Sm, R.M. Klein & Delprete (Rubiaceae) is found in the existing Atlantic Forest in the South of Brazil, in the Paraná and Santa Catarina States. The members of Rubiaceae are characterized chemically by the presence of alkaloids, some pharmacological properties of which include antifungal, antibacterial, analgesic, antioxidant, antimutagenic, and antiviral activities. In this study, we report the results of anatomical, morphological, and histochemical analyses of the leaves and stems of the Rubiaceae family member, P. fractistipula. The anatomical analysis involved of light microscopy and scanning electron microscopy. Morpho-anatomical and histochemical characterization were made using standard methodology. The isolated compounds were identified by Nuclear Magnetic Resonance spectroscopic analysis. The following structures are highlighted as the distinctive features of the species: presence of petiolate leaves and a petiole base, leaf blade with smooth cuticle on both surfaces, paracytic stomata, and, dorsiventral mesophyll and presence of trichomes on the leaves and stems. Phytosteroids, identified as β-sitosterol and campesterol, were observed in the hexane fraction of the stem. Future studies should focus on the isolation of other fractions of interest and their characterization through specific biological and cytotoxicity assays.

Agrobacterium rhizogenes-mediated transformation of Hypericum sinaicum L. for the development of hairy roots containing hypericin

Hypericum sinaicum L. is an endangered Egyptian medicinal plant of high importance due to the presence of naphthodianthrones (hypericins), which have photodynamic properties and pharmaceutical potential. We sought to assess H. sinaicum ability to develop hairy roots that could be cultured in contained conditions in vitro and used as a source for hypericin production. We used four A. rhizogenes strains differing in their plasmids and chromosomal backgrounds to inoculate excised H. sinaicum root, stem and leaf explants to induce hairy root development. Additionally, inoculum was applied to shoots held in Rockwool cubes supporting their stand after removal of the root system. All explant types were susceptible to A. rhizogenes although stem explants responded more frequently (over 90%) than other explant types. The A4 and A4T A. rhizogenes strains were highly, and equally effective in hairy root induction on 66-72% of explants while the LBA1334 strain was the most effective in transformation of shoots. Sonication applied to explants during inoculation enhanced the frequency of hairy root development, the most effective was 60 s treatment doubling the percentage of explants with hairy roots. However, shoot transformation was the most effective approach as shoots developed hairy roots within 10 days after inoculation. Molecular analyses confirmed that the established hairy root cultures in vitro were indeed obtained due to a horizontal gene transfer from bacteria. These cultures grew fast and the hypericin content in hairy roots was about two fold higher than in H. sinaicum plants as determined by HPLC.

Specification of Bacteriophage Isolated Against Clinical Methicillin-Resistant Staphylococcus Aureus

OBJECTIVES: The emergence of resistant bacteria is being increasingly reported around the world, potentially threatening millions of lives. Amongst resistant bacteria, methicillin-resistant Staphylococcus aureus (MRSA) is the most challenging to treat. This is due to emergent MRSA strains and less effective traditional antibiotic therapies to Staphylococcal infections. The use of bacteriophages (phages) against MRSA is a new, potential alternate therapy. In this study, morphology, genetic and protein structure of lytic phages against MRSA have been analysed. METHODS: Isolation of livestock and sewage bacteriophages were performed using 0.4 μm membrane filters. Plaque assays were used to determine phage quantification by double layer agar method. Pure plaques were then amplified for further characterization. Sulfate-polyacrylamide gel electrophoresis and random amplification of polymorphic DNA were run for protein evaluation, and genotyping respectively. Transmission electron microscope was also used to detect the structure and taxonomic classification of phage visually. RESULTS: Head and tail morphology of bacteriophages against MRSA were identified by transmission electron microscopy and assigned to the Siphoviridae family and the Caudovirales order. CONCLUSION: Bacteriophages are the most abundant microorganism on Earth and coexist with the bacterial population. They can destroy bacterial cells successfully and effectively. They cannot enter mammalian cells which saves the eukaryotic cells from lytic phage activity. In conclusion, phage therapy may have many potential applications in microbiology and human medicine with no side effect on eukaryotic cells.

RNA viruses in trypanosomatid parasites: a historical overview

Viruses of trypanosomatids are now being extensively studied because of their diversity and the roles they play in flagellates' biology. Among the most prominent examples are leishmaniaviruses implicated in pathogenesis of Leishmania parasites. Here, we present a historical overview of this field, starting with early reports of virus-like particles on electron microphotographs, and culminating in detailed molecular descriptions of viruses obtained using modern next generation sequencing-based techniques. Because of their diversity, different life cycle strategies and host specificity, we believe that trypanosomatids are a fertile ground for further explorations to better understand viral evolution, routes of transitions, and molecular mechanisms of adaptation to different hosts.

Avaliação de protetores solares contendo filtros encapsulados/incorporados em matriz de sílica mesoporosa ordenada do tipo SBA-15 / Evaluation of sunscreens containing encapsulated/entrapped UV filters in ordered mesoporous silica type SBA-15

Filtros orgânicos são amplamente utilizados em formulações fotoprotetoras, com habilidade de absorver radiações ultravioleta (UV). Contudo, parte destes compostos possuem limitações, como: fotoinstabilidade, permeação cutânea e fotossensibilização e entre outros. Este trabalho envolveu a síntese de matriz mesoporosa do tipo SBA-15, encapsulação/incorporação de ρ-metoxicinamato de octila (MCO), benzofenona-3 (BZF-3) e avobenzona (AVO) na SBA-15 para aplicação em formulações fotoprotetoras. Fez-se a determinação da eficácia in vitro dos filtros encapsulados/incorporados combinados a ingrediente cosmético; o preparo de bastão fotoprotetor e determinação eficácia estimada; a avaliação do potencial de irritação ocular dos bastões por HET-CAM - Hen's Egg Test - Chorioallantoic Membrane, e a avaliação da permeação/retenção cutânea e perfil de biodistribuição dos filtros. Para a caracterização dos materiais foram empregadas técnicas físico-químicas e analíticas. As medidas de adsorção/dessorção de N2 mostrou que as amostras dos filtros solares encapsulados/incorporados apresentaram diminuição na área superficial e volume de poro (V), indicando que os filtros solares foram encapsulados/incorporados na superfície e nos poros da SBA-15. Os resultados de Espalhamento de raios X a baixo ângulo evidenciaram que os filtros solares não afetaram a estrutura hexagonal da SBA-15. Por TG/DTG e análise elementar foi possível determinar a quantidade de filtros solares na superfície e nos mesoporos da SBA-15. Enquanto, as curvas DSC e DTA revelaram aumento na estabilidade térmica da AVO e BZF-3, quando encapsulados/incorporados. Os resultados da eficácia fotoprotetora in vitro mostraram que a combinação dos três filtros solares encapsulados/incorporados na SBA-15 promoveram aumento de 52% no fator proteção solar (FPS), enquanto que, na formulação fotoprotetora contendo os três filtros encapsulados/incorporados, o aumento foi de 94%. O ensaio de HET-CAM evidenciou que os bastões contendo SBA-15 e os filtros encapsulados/incorporados não foram irritantes. O ensaio de permeação/retenção cutânea mostrou que o processo de encapsulação/incorporação da BZF-3 promoveu diminuição de sua permeação em todos os tempos de exposição. As quantidades permeadas de AVO e MCO ficaram abaixo do limite de quantificação nos tempos 6 e 12 h, no entanto, no tempo de 24 h foi possível quantificá-los. As quantidades dos filtros solares retidas na pele a partir da formulação contendo os filtros solares encapsulados/incorporados na SBA-15 (F4) foram menores (tempos 6 e 12 h) em comparação à formulação contendo os filtros solares não encapsulados (F3). A investigação da biodistribuição dos filtros solares mostrou que a retenção total na pele, como na derme, foi menor na formulação F4 em comparação à F3. O estudo comparativo entre pele suína e a pele humana mostrou que as quantidades de BZF-3 e AVO permeadas e retidas na pele suína foram superiores do que em relação à humana para ambas as formulações (F4 e FR). Pela técnica de biodistribuição, foi possível determinar que os filtros solares oriundos das formulações F3 e referência (FR) apresentaram maior retenção destes compostos na derme do que em outras camadas da pele. Contudo, observou-se que os filtros encapsulados apresentaram taxa reduzida de retenção na derme

Organic Filters are chemical compounds widely used in sunscreens formulations with the ability to absorb ultraviolet radiation (UV). Despite the effectiveness of these compounds in UV radiation protection, disadvantages related to their photo instability, potential skin permeation and photo sensibility pose significant challenges for improving these products. The aim of this work was to synthesize mesoporous matrix SBA-15, encapsulation/entrapping of octyl methoxycinnamate (OMC), benzophenone-3 (BZF-3) and avobenzone (AVO) into SBA-15 for application in photoprotective formulations. It was accessed in vitro photoprotection efficacy and in vitro photostability assay of encapsulated/entrapped UV filters combined with cosmetic ingredient and photoprotective stick formulations; evaluation of the ocular irritation potential of photoprotective stick formulations by in vitro method HET-CAM - Hen's Egg Test - Chorioallantoic Membrane; evaluation the skin permeation/deposition and biodistribution profile of photoprotective stick formulations. The decrease in the surface area and in mesoporous volume (V) observed in the nitrogen adsorption desorption isotherms of encapsulated/entrapped samples indicated that UV filters were efficiently encapsulated/entrapped into SBA-15. Additionally, SAXS results showed that UV filters did not affected the hexagonal structure of the mesoporous material and that these compounds filled the SBA-15 pores. TG/DTG and elemental analysis were efficient tools to confirm the presence and the quantity of UV filters into SBA-15. DTA and DSC curves of encapsulated/entrapped materials showed that the thermal stability of AVO and BZF-3 were increased. On the other hand, DSC curves of encapsulated/entrapped materials demonstrated that thermal stability of OMC was not increase. The in vitro photoprotective efficacy results demonstrated that the combination of the three sunscreens encapsulated/entrapped into SBA-15 increased 52.0% the SPF values, while the stick formulation containing the UV filters encapsulated/entrapped, the increase was 94.0%. Delivery experiments using porcine skin demonstrated that the encapsulation/entrapping process of UV filters resulted the decreased of BZF-3 permeation and deposition in skin (6 and 12 hours). The cutaneous biodistribution profile of UV filters showed that the deposition of these compounds from encapsulated/entrapped stick formulation (F4) was significantly lower than that from UV filters stick formulations (F3) in the total slices of the skin and dermis. The comparative study between porcine skin and human skin demonstrated that the amounts of BZF-3 and AVO permeated and deposited in porcine skin were higher than in human skin for both formulations (F4 and FR - reference formulation). By the biodistribution technique it was possible to determine that the UV filters from the formulations F3 and FR presented higher retention of these compounds in the dermis than in other layers of the skin. On the other hand, it was observed that the encapsulated UV filters presented low retention rate into dermis

Development and evaluation of ultrasound contrast agents with AS1411-conjugated nanoparticles with liquid core / 中南大学学报(医学版)

To prepare AS1411 targeted nano-ultrasonic contrast agent with liquid core, and to evaluate its ability for ultrasonic contrast enhancement and targeting MCF-7 cell in vitro.
 Methods: The modified solvent evaporation, self-synthesized membrane material and perfluorobrominane (PFOB) was used to form nano-ultrasonic contrast agent with PFOB core (nanoparticles, NP); then N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride and N-hydroxysuccinimide (EDC/NHS) catalysis was used to connect AS1411 to the surface of NP to prepare NP-AS1411. The transmission electron microscopy was chosen to check the morphology of NP-AS1411. The size, surface charge, encapsulation efficiency, biocompatibility, the contrast grey value and the stability of NP-AS1411 and NP were compared. Whether AS411 was attached to the surface of NP was checked by gel electrophoresis. Fluorescence microscopy and flow cytometry were performed to examine the targeting ability of AS1411.
 Results: NP-AS1411 was a shell-nuclear structure under the electron microscope. Its size was at (245.4±16.5) nm, which was larger than that of NP (P=0.05). There was no significant difference in surface charge and encapsulation efficiency between NP-AS1411 and NP (P>0.05). In the MTT experiment, the cell viability decreased significantly at high concentration of NP-AS411 (25 mg/mL) after incubation for 24 h compared with the control group (0 mg/mL ) (P0.05). The contrast grey value of AS1411-NP was 80.1±9.2 after keeping at room temperature for 24 h, which showed no obviously change comparing with that before the treatment (P>0.05). The size of NP-AS1411didn't change too (P>0.05). The results of gel electrophoresis demonstrated that the AS1411 connecting to the surface of NP was the most when the molar ratio of NP:AS1411 was at 40:1. Flow cytometry analysis confirmed that NP and NP-AS1411 were combined with MCF-7 cells separately but the fluorescence produced by the combination of NP-AS1411 and MCF-7 was more intense.
 Conclusion: The modified solvent evaporation and EDC/NHS catalysis could successfully prepare ultrasound contrast agents with aptamer-conjugated nanoparticles with liquid core. The targeted ultrasonic contrast agents with liquid core possess good ultrasonic contrast enhancement ability in vitro, stability and specificity as well.