Advances in Tumor Organoids for the Evaluation of Drugs: A Bibliographic Review.

Tumor organoids are defined as self-organized three-dimensional assemblies of heterogeneous cell types derived from patient samples that mimic the key histopathological, genetic, and phenotypic characteristics of the original tumor. This technology is proposed as an ideal candidate for the evaluation of possible therapies against cancer, presenting advantages over other models which are currently used. However, there are no reports in the literature that relate the techniques and material development of tumor organoids or that emphasize in the physicochemical and biological properties of materials that intent to biomimicry the tumor extracellular matrix. There is also little information regarding the tools to identify the correspondence of native tumors and tumoral organoids (tumoroids). Moreover, this paper relates the advantages of organoids compared to other models for drug evaluation. A growing interest in tumoral organoids has arisen from 2009 to the present, aimed at standardizing the process of obtaining organoids, which more accurately resemble patient-derived tumor tissue. Likewise, it was found that the characteristics to consider for the development of organoids, and therapeutic responses of them, are cell morphology, physiology, the interaction between cells, the composition of the cellular matrix, and the genetic, phenotypic, and epigenetic characteristics. Currently, organoids have been used for the evaluation of drugs for brain, lung, and colon tumors, among others. In the future, tumor organoids will become closer to being considered a better model for studying cancer in clinical practice, as they can accurately mimic the characteristics of tumors, in turn ensuring that the therapeutic response aligns with the clinical response of patients.

Cytotoxicity and Genotoxicity of Azobenzene-Based Polymeric Nanocarriers for Phototriggered Drug Release and Biomedical Applications.

Drug nanoencapsulation increases the availability, pharmacokinetics, and concentration efficiency for therapeutic regimes. Azobenzene light-responsive molecules experience a hydrophobicity change from a polar to an apolar tendency by trans-cis photoisomerization upon UV irradiation. Polymeric photoresponse nanoparticles (PPNPs) based on azobenzene compounds and biopolymers such as chitosan derivatives show prospects of photodelivering drugs into cells with accelerated kinetics, enhancing their therapeutic effect. PPNP biocompatibility studies detect the safe concentrations for their administration and reduce the chance of side effects, improving the effectiveness of a potential treatment. Here, we report on a PPNP biocompatibility evaluation of viability and the first genotoxicity study of azobenzene-based PPNPs. Cell line models from human ventricular cardiomyocytes (RL14), as well as mouse fibroblasts (NIH3T3) as proof of concept, were exposed to different concentrations of azobenzene-based PPNPs and their precursors to evaluate the consequences on mitochondrial metabolism (MTT assay), the number of viable cells (trypan blue exclusion test), and deoxyribonucleic acid (DNA) damage (comet assay). Lethal concentrations of 50 (LC50) of the PPNPs and their precursors were higher than the required drug release and synthesis concentrations. The PPNPs affected the cell membrane at concentrations higher than 2 mg/mL, and lower concentrations exhibited lesser damage to cellular genetic material. An azobenzene derivative functionalized with a biopolymer to assemble PPNPs demonstrated biocompatibility with the evaluated cell lines. The PPNPs encapsulated Nile red and dofetilide separately as model and antiarrhythmic drugs, respectively, and delivered upon UV irradiation, proving the phototriggered drug release concept. Biocompatible PPNPs are a promising technology for fast drug release with high cell interaction opening new opportunities for azobenzene biomedical applications.

Genotoxicity of organic material extracted from particulate matter of alternative fuels.

Global demand for energy is rapidly increasing, and resources for the production of petroleum-based fuels are running out. For this, renewable fuels like biodiesel and hydrotreated vegetable oil biofuel are considered important alternatives to replace such fuels. In this study, we evaluated the in vitro genotoxicity effect on HepG2 cells of organic material extracted from particulate matter emissions of an engine fueled with conventional diesel or mixtures of diesel with 10% of biomass. The emissions were collected in two operational modes, 2410 rpm (slope simulation) and 1890 rpm (plane). Genotoxicity was evaluated through two methods, chromosomal aberration test and the alkaline comet assay. The former did not show any genotoxic effect, but the latter exhibited a statistically significant effect despite the operational mode of the engine and the concentration organic material extracted. In conclusion, regardless of the concentration of organic material extracted from particulate matter, the operational mode of the engine, or the fuel used, a significant damage of the DNA was found. In general, at the physicochemical level, a decrease in the amount of emissions of the used fuels is not directly related to a decrease in the genotoxicity potential.

Detection of heterogeneous vancomycin intermediate resistance in MRSA isolates from Latin America.

BACKGROUND: Vancomycin is a common first-line option for MRSA infections. The heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) phenotype is associated with therapeutic failure. However, hVISA isolates are usually reported as vancomycin susceptible by routine susceptibility testing procedures. OBJECTIVES: To detect and characterize the hVISA phenotype in MRSA isolates causing infections in nine Latin American countries. METHODS: We evaluated a total of 1189 vancomycin-susceptible MRSA isolates recovered during 2006-08 and 2011-14. After an initial screening of hVISA using glycopeptide-supplemented agar strategies, the detection of hVISA was performed by Etest (GRD) and Macro-method (MET). Isolates deemed to be hVISA were subjected to population analysis profile/AUC (PAP/AUC) and WGS for further characterization. Finally, we interrogated alterations in predicted proteins associated with the development of the VISA phenotype in both hVISA and vancomycin-susceptible S. aureus (VSSA) genomes. RESULTS: A total of 39 MRSA isolates (3.3%) were classified as hVISA (1.4% and 5.6% in MRSA recovered from 2006-08 and 2011-14, respectively). Most of the hVISA strains (95%) belonged to clonal complex (CC) 5. Only 6/39 hVISA isolates were categorized as hVISA by PAP/AUC, with 6 other isolates close (0.87-0.89) to the cut-off (0.9). The majority of the 39 hVISA isolates exhibited the Leu-14→Ile (90%) and VraT Glu-156→Gly (90%) amino acid substitutions in WalK. Additionally, we identified 10 substitutions present only in hVISA isolates, involving WalK, VraS, RpoB and RpoC proteins. CONCLUSIONS: The hVISA phenotype exhibits low frequency in Latin America. Amino acid substitutions in proteins involved in cell envelope homeostasis and RNA synthesis were commonly identified. Our results suggest that Etest-based methods are an important alternative for the detection of hVISA clinical isolates.

Photosensitive nanocarriers for specific delivery of cargo into cells.

Nanoencapsulation is a rapidly expanding technology to enclose cargo into inert material at the nanoscale size, which protects cargo from degradation, improves bioavailability and allows for controlled release. Encapsulation of drugs into functional nanocarriers enhances their specificity, targeting ability, efficiency, and effectiveness. Functionality may come from cell targeting biomolecules that direct nanocarriers to a specific cell or tissue. Delivery is usually mediated by diffusion and erosion mechanisms, but in some cases, this is not sufficient to reach the expected therapeutic effects. This work reports on the development of a new photoresponsive polymeric nanocarrier (PNc)-based nanobioconjugate (NBc) for specific photo-delivery of cargo into target cells. We readily synthesized the PNcs by modification of chitosan with ultraviolet (UV)-photosensitive azobenzene molecules, with Nile red and dofetilide as cargo models to prove the encapsulation/release concept. The PNcs were further functionalized with the cardiac targeting transmembrane peptide and efficiently internalized into cardiomyocytes, as a cell line model. Intracellular cargo-release was dramatically accelerated upon a very short UV-light irradiation time. Delivering cargo in a time-space controlled fashion by means of NBcs is a promising strategy to increase the intracellular cargo concentration, to decrease dose and cargo side effects, thereby improving the effectiveness of a therapeutic regime.

First Colombian consensus on congenital Chagas and clinical approach for women of child-bearing age diagnosed with Chagas / Primer consenso colombiano sobre Chagas congénito y orientación clínica a mujeres en edad fértil con diagnóstico de Chagas

Congenital transmission of Chagas disease has not been extensively studied in Colombia, and there are no standardized processes in the health system regarding the specific diagnosis, treatment and follow-up of this disease. To generate recommendations on congenital Chagas disease and Chagas in women of childbearing age in Colombia, a consensus of experts was developed. An extensive literature search through the Medline database was carried out using the MeSH terms: «Chagas disease/congenital¼, «prevention and control¼, «diagnosis¼, «therapeutics¼ and «pregnancy¼. Appropriate abstracts were selected and the full texts were analyzed. The relevant information was synthesized, classified, and organized into tables and figures and was presented to a panel of experts, which was composed of 30 professionals from various fields. Based on the Delphi methodology, three rounds of consultation were conducted. The first and second rounds were based on electronic questionnaires that measured the level of consensus of each question among the participants. The third round was based on a face-to-face discussion focusing on those questions without consensus in the previous consultations. The evidence was adapted to national circumstances on a case-by-case basis, and the content the final document was approved. These recommendations are proposed for use in routine medical practice by health professionals in Colombia.

La transmisión congénita de la enfermedad de Chagas ha sido poco estudiada en Colombia y existen pocos procedimientos rutinarios en el sistema de salud para el manejo de esta enfermedad. Por ello se desarrolló un consenso de expertos dirigido a generar recomendaciones de diagnóstico y tratamiento de Chagas con- génito y orientación a mujeres en edad fértil. Con ese propósito se realizó una búsqueda extensiva de la literatura, empleando una combinación de términos Mes (Chagas, Chagas congénito, prevención, control, diagnóstico, tratamiento y embarazo) para reflejar el estado del arte en cada tema de interés. Después de ello, se leyeron los resúmenes y aquellos seleccionados para análisis del texto completo. La literatura relevante se sintetizo, clasifico y organizo en tablas y se presentó al panel de expertos, el cual estaba constituido por 30 profesionales en diferentes áreas. Mediante la metodología Delphi se realizaron 2 rondas de cuestionarios virtuales y una reunión presencial en los cuales se evaluaron los niveles de acuerdo entre los participantes. Los puntos con falta de consenso durante las 2 rondas virtuales se expusieron durante las mesas de discusión en la ronda presencial. La evidencia utilizada se adaptó a las particularidades nacionales según el caso y se aprobó el contenido del documento final. Se propone que estas recomendaciones sean usadas por profesionales de la salud en Colombia.

Detection of Trypanosoma cruzi antibodies in multitransfused patients in Colombia.

INTRODUCTION: Chagas disease is a public health problem in Latin America. Even though vector-borne infection is the most important transmission mode for this disease, other modes such as transfusions require evaluation. OBJECTIVE: To describe the prevalence of T. cruzi infection in multitransfused patients. MATERIALS AND METHODS: We detected IgG antibodies against T. cruzi by two immunoassays in samples from multitransfused patients in four hospitals located in Bogotá and Medellín, Colombia. We analyzed the association with known risk factors, and we calculated the odds ratios (OR) with 95% confidence intervals using Stata 11™ statistical software. RESULTS: In total, 479 samples were tested. Overall, T. cruzi antibody prevalence was 1.88% (nine patients). Five were onco-hematological patients, two were hemodialyzed, one had thalassemia, and one had suffered acute blood loss. We found no hemophilia patients. There was no association between known risk factors for transfusion-transmitted infection (such as the number of transfusion events, number of blood units and type of blood component) and the presence of anti-T. cruzi antibodies in this study. Only the hepatitis C virus infection showed a positive association with the presence of anti-T. cruzi antibodies (OR=5.68, 95% CI: 1.36-23.63). CONCLUSIONS: The results of this study showed a low frequency of T. cruzi infection in multitransfused patients, suggesting that the risk of transfusion infection in Colombia is low. Known risk factors for transfusion-related infection were not associated with the presence of anti-T. cruzi antibodies.

Detección de anticuerpos contra Trypanosoma cruzi en pacientes multitransfundidos, Colombia / Detection of Trypanosoma cruzi antibodies in multitransfused patients in Colombia

Resumen Introducción. La enfermedad de Chagas es un problema de salud pública en Latinoamérica y, aunque la transmisión vectorial es la más importante, deben evaluarse otras formas de transmisión, como la de las transfusiones. Objetivo. Describir la prevalencia de infección con Trypanosoma cruzi en pacientes sometidos a múltiples transfusiones o multitransfundidos. Materiales y métodos. Se detectaron anticuerpos IgG contra T. cruzi mediante dos inmunoensayos en muestras tomadas de pacientes sometidos a múltiples transfusiones en cuatro hospitales de Bogotá y Medellín, Colombia. Se analizó la asociación de factores de riesgo conocidos y se calcularon las razones de momios (odds ratio, OR) con un intervalo de confianza de 95 % (IC) utilizando el programa Stata 11(tm). Resultados. Se evaluaron 479 muestras. La prevalencia de anticuerpos contra T. cruzifue de 1,88 % (nueve pacientes): cinco pacientes remitidos de oncohematología, dos de hemodiálisis, uno tenía talasemia y uno había sufrido pérdida súbita y abundante de sangre. No se halló ningún paciente con hemofilia que resultara positivo, ni relación de los factores de riesgo de infección asociados con la transfusión de componentes sanguíneos, como el número de transfusiones, la cantidad de unidades de sangre y el tipo de componente, con la presencia de anticuerpos anti-T. cruzi. Solo se encontró relación entre la infección con el virus de la hepatitis C y la presencia de anticuerpos anti-T. cruzi (OR=5,68; IC95% 1,36-23,63). Conclusión. La frecuencia de infección por T. cruzi hallada en este grupo de pacientes sugiere que el riesgo de infección por transfusiones en Colombia es bajo. No se encontró relación entre los factores de riesgo asociados con la transfusión y la presencia de anticuerpos anti-T. cruzi.

Abstract Introduction: Chagas disease is a public health problem in Latin America. Even though vector-borne infection is the most important transmission mode for this disease, other modes such as transfusions require evaluation. Objective: To describe the prevalence of T. cruzi infection in multitransfused patients. Materials and methods: We detected IgG antibodies against T. cruzi by two immunoassays in samples from multitransfused patients in four hospitals located in Bogotá and Medellín, Colombia. We analyzed the association with known risk factors, and we calculated the odds ratios (OR) with 95% confidence intervals using Stata 11(tm) statistical software. Results: In total, 479 samples were tested. Overall, T. cruzi antibody prevalence was 1.88% (nine patients). Five were onco-hematological patients, two were hemodialyzed, one had thalassemia, and one had suffered acute blood loss. We found no hemophilia patients. There was no association between known risk factors for transfusion-transmitted infection (such as the number of transfusion events, number of blood units and type of blood component) and the presence of anti-T. cruzi antibodies in this study. Only the hepatitis C virus infection showed a positive association with the presence of anti-T. cruzi antibodies (OR=5.68, 95% CI: 1.36-23.63). Conclusions: The results of this study showed a low frequency of T. cruzi infection in multitransfused patients, suggesting that the risk of transfusion infection in Colombia is low. Known risk factors for transfusion-related infection were not associated with the presence of anti-T. cruzi antibodies.

Primer consenso colombiano sobre Chagas congénito y orientación clínica a mujeres en edad fértil con diagnóstico de Chagas / First Colombian consensus on congenital Chagas and clinical approach to women of fertile age diagnosed with Chagas

La transmisión congénita de la enfermedad de Chagas ha sido poco estudiada en Colombia y existen pocos procedimientos rutinarios en el sistema de salud para el manejo de esta enfermedad. Por ello se desarrolló un consenso de expertos dirigido a generar recomendaciones de diagnóstico y tratamiento de Chagas congénito y orientación a mujeres en edad fértil. Con ese propósito se realizó una búsqueda extensiva de la literatura, empleando una combinación de términos MeSH (Chagas, Chagas congénito, prevención, control, diagnóstico, tratamiento y embarazo) para reflejar el estado del arte en cada tema de interés. Después de ello, se leyeron los resúmenes y aquellos seleccionados para análisis del texto completo. La literatura relevante se sintetizó, clasificó y organizó en tablas y se presentó al panel de expertos, el cual estaba constituido por 30 profesionales en diferentes áreas. Mediante la metodología Delphi se realizaron 2 rondas de cuestionarios virtuales y una reunión presencial en los cuales se evaluaron los niveles de acuerdo entre los participantes. Los puntos con falta de consenso durante las 2 rondas virtuales se expusieron durante las mesas de discusión en la ronda presencial. La evidencia utilizada se adaptó a las particularidades nacionales según el caso y se aprobó el contenido del documento final. Se propone que estas recomendaciones sean usadas por profesionales de la salud en Colombia.

Congenital transmission of Chagas disease has not been extensively studied in Colombia, and there are no standardized processes in the health system regarding the specific diagnosis, treatment and follow-up of this disease. In order to generate recommendations on congenital Chagas disease and Chagas in women of childbearing age in Colombia, a consensus of experts was developed. An extensive literature search through the Medline database was carried out using the MeSH terms: " Chagas disease/congenital " , " prevention and control " , " diagnosis " , " therapeutics " and " pregnancy " . Appropriate abstracts were selected and the full texts were analyzed. The relevant information was synthesized, classified, and organized into tables and figures and was presented to a panel of experts, which was composed of 30 professionals from various fields. Based on the Delphi methodology, three rounds of consultation were conducted. The first and second rounds were based on electronic questionnaires that measured the level of consensus of each question among the participants. The third round was based on a face-toface discussion focusing on those questions without consensus in the previous consultations. The evidence was adapted to national circumstances on a case-by-case basis, and the content the final document was approved. These recommendations are proposed for use in routine medical practice by health professionals in Colombia.