Schiff bases are diverse organic compounds with an azomethine structure (–C=N–), holding potential in both chemistry and biology. They serve as catalysts, stabilizers, and exhibit various biological activities. The molecular structure of Schiff bases influences their biological properties, including antimicrobial effects. Redox-active compounds with more negative potentials tend to be more effective against microbes. In one of our recent studies, we explored the antimicrobial properties of two Schiff bases derivatives, SB-1 ((E)-4-amino-3-((3,5-di-tert-butyl-2-hydroxybenzylidene)amino) and SB-2 ((E)-2-((4-nitrobenzilidene)amino)aniline). SB-1 showed antibacterial activity against certain Gram-positive bacteria, while SB-2 did not. The difference in their cyclic voltametric profiles, especially SB-1’s more negative reduction potential, prompted us to carry out further characterizations, including scan-rate studies, solvent analysis, and computational calculations. We found that SB-1, which presents a stable intramolecular hydrogen bond, undergoes irreversible oxidation, likely at the –NH2 group, and a quasi-reversible reduction via an intramolecular reductive coupling of the (–C=N–) azomethine group, supported by orbital theoretical calculations. This research sheds light on the potential applications of Schiff bases in antimicrobial contexts, guided by their redox properties and structure. –C=N–, CN –C=N– , C N biology catalysts stabilizers activities effects Redoxactive Redox active microbes studies derivatives SB1 SB 1 SB- E4amino33,5ditertbutyl2hydroxybenzylideneamino E4amino335ditertbutyl2hydroxybenzylideneamino Eaminoditertbutylhydroxybenzylideneamino E 4 amino 3 3,5 di tert butyl 2 hydroxybenzylidene 5 ((E)-4-amino-3-((3,5-di-tert-butyl-2-hydroxybenzylidene)amino SB2 E24nitrobenzilideneaminoaniline. E24nitrobenzilideneaminoaniline Enitrobenzilideneaminoaniline nitrobenzilidene aniline . ((E)-2-((4-nitrobenzilidene)amino)aniline) Grampositive Gram positive bacteria not profiles SB1s SBs s characterizations scanrate scan rate analysis calculations SB1, 1, bond oxidation NH2 NH –NH group quasireversible quasi reversible (–C=N– contexts –C=N E4amino33 5ditertbutyl2hydroxybenzylideneamino ditertbutyl hydroxybenzylideneamino 35 3, nitrobenzilideneaminoaniline ((E)-2-((4-nitrobenzilidene)amino)aniline (–C=N Eamino E4amino3 ditertbutylhydroxybenzylideneamino E4amino

ABSTRACT Objective: Sorafenib significantly prolonged progression-free survival in patients with iodine-refractory advanced thyroid cancer. The present study was initiated before sorafenib was approved in Colombia and therefore represents an effort by an oncology institution to evaluate its efficacy and safety in this population. Subjects and methods: This phase II clinical trial had a single treatment arm. We included adult patients with progressive metastatic iodine-refractory thyroid cancer who received treatment with sorafenib 800 mg/day (400 mg every 12 hours) up to a maximum of 24 months or until the occurrence of limiting related toxicity, the progression of the disease, or voluntary withdrawal. Results: Nineteen patients received the treatment and were included in the safety analysis. However, for the efficacy analysis, 6 patients were excluded because they received only one month of therapy. Thirteen (68%) patients were women, and the mean age at diagnosis was 61.8 years. No complete responses were observed; 5 patients had a partial response (35.7%), 6 patients had stable disease, and 3 showed progression. Mean progression-free survival was calculated at 18 months (95% CI 10.7-20.3). Overall survival was estimated at 21.3 months (95% CI 17.8-24.8). Conclusion: For the first time in Colombia, the efficacy of sorafenib was evaluated in patients with advanced and progressive thyroid carcinoma refractory to radioactive iodine, with an efficacy and a safety profile similar to those previously reported.

Abstract Objective: to describe the initial experience in Colombia of locally advanced melanoma treated by isolated limb perfusion and compare the response rate of our melanoma subtypes with the literature. Methods: descriptive, retrospective study of a series of patients selected between 2007 and 2016. Qualitative variables were analyzed with proportions and frequencies, and quantitative variable with central tendency measures and measures of dispersion. Results: 11 patients were treated by isolated limb perfusion. After the treatment, seven patients (63.6%) had partial response, two patients (18.2%) had stable disease and two patients (18.2%) had disease progression. Five patients (45.5%) had mild complications. Conclusions: Isolated limb perfusion is still an important treatment strategy for locally advanced melanoma, with the goal of improving the patient quality of life. The response can change according to the type of melanoma, and could be smaller in patients with acral lentiginous and nodular melanoma, although we cannot make this conclusion with this type of study because it has low power and lack of a comparison group.

Resumen Objetivo: describir la experiencia inicial en Colombia en el manejo del melanoma de extremidad con perfusión aislada y comparar la respuesta de los subtipos histológicos más frecuentes en Colombia con la literatura. Materiales y métodos: estudio descriptivo, retrospectivo de una serie de pacientes con diagnóstico de melanoma con metástasis en tránsito tratados con perfusión aislada de extremidad, seleccionados entre 2007 y 2016. Las variables cualitativas se analizaron con frecuencias absolutas y relativas. Las cuantitativas con medidas de tendencia central y dispersión. Resultados: 11 pacientes fueron tratados con perfusión aislada de extremidad. Hubo respuesta parcial en siete pacientes (63,6%), enfermedad estable en dos pacientes (18,2%) y progresión en dos pacientes (18,2%). Después del tratamiento, cinco pacientes (45,5%) presentaron complicaciones menores. Conclusiones: la perfusión aislada sigue siendo importante para el tratamiento del melanoma localmente avanzado con el fin de mejorar la calidad de vida de los pacientes. La respuesta puede cambiar según el tipo clínico de melanoma, siendo menor, según este estudio, en pacientes con melanoma lentiginoso acral y nodular, aunque por el bajo poder, esto no se puede concluir.

Resumo Este artigo analisa as políticas de redução de cultivos ilícitos na Colômbia no período de 1990 a 2018, a partir de uma revisão bibliográfica e análise documental. A perspectiva hegemônica militarista e proibicionista é comparada com alternativas locais que buscam enfrentar, de maneira abrangente, os problemas estruturais do campo na Colômbia. A trajetória do Plano Alternativo, promovido pelos governadores dos territórios produtores, e do Programa Nacional Abrangente para a Substituição de Culturas Ilícitas, resultante do Acordo de Paz de 2016, revela a hegemonia do proibicionismo estadunidense. Isso traz impactos não apenas para a Colômbia, mas para a América Latina, já que os temas drogas, segurança e controle de fronteiras formam parte da agenda geopolítica dos Estados Unidos.

Abstract This paper analyzes the mitigation policies of illegal cropping expansion in Colombia in the period 1990 to 2018 from the literature review and document analysis. It contrasted the hegemonic militarist and prohibitionist perspective with local alternatives that aim an integral confrontation of the structural problems of Colombian rurality. The historicity of the Alternate Plan, driven by governors of producing territories, and the National Comprehensive Program for the Substitution of Illicit Crops, derived from the 2016 peace agreement, reveals the hegemony of the United States prohibitionism. This preponderance affects Colombia as well as Latin America because of drug agendas, security and border control constitute the US geopolitics.

Resumen Este artículo analiza las políticas de mitigación de la expansión de los cultivos ilegalizados en Colombia en el periodo comprendido entre 1990 y 2018, a partir de la revisión bibliográfica y el análisis documental. Se contrasta la perspectiva hegemónica militarista y prohibicionista con alternativas locales que buscan el enfrentamiento integral de problemas estructurales de la ruralidad colombiana. La historicidad del Plan Alterno, impulsado por los gobernadores de los territorios productores, y del Programa Nacional Integral de Sustitución de Cultivos Ilícitos, derivado del Acuerdo de Paz de 2016, revela la hegemonía del prohibicionismo estadounidense. Esa preponderancia impacta no solo a Colombia, sino a Latinoamérica, puesto que las agendas de drogas, seguridad y control de fronteras son constitutivas de la geopolítica estadounidense.

ABSTRACT Botrytis cinerea is a ubiquitous necrotrophic filamentous fungal pathogen, causing the “grey mold” disease in a wide range of plants, including species of importance in the food industry. Recently, we reported the use of fac-[Re(I)(CO)3(2,2’-bpy)L]PF6 (C3) and fac-[Re(I)(CO)3(4,4′-dimethyl-2,2′-bpy)L]PF6 (C4) complexes as biomarkers for yeasts and bacteria. Nevertheless, the use of these complexes to stain filamentous fungi, such as Botrytis cinerea, has not been explored so far. Since Botrytis cinerea exhibits a dynamic multilayer cell wall that changes the composition during normal growth, in both their hyphae and conidia, is not possible to directly extrapolate the use of both C3 and C4 as biomarkers for Botrytis cinerea without an experimental approach. In this work, we explored new features of the luminescent compounds C3 and C4 as biomarkers for the higher filamentous fungi Botrytis cinerea, including conidia and juvenile hyphae. We found that, with the new protocol proposed, both C3 and C4 were suitable to stain conidia with a simple procedure since no cell permeabilization is required. Additionally, these results suggest that C3 and C4 can selectively stain living conidia, allowing the differentiation from non-germinating conidia. This point opens a new focus of development for rhenium (I) tricarbonyl complexes as new fluorescent biomarkers for Botrytis cinerea with potential properties as vital staining.

ABSTRACT Several research to explore the possible conversion of CO2 using rhenium(I) tricarbonyl complexes have been reported the last years. In the present work, we investigated a potential use of fac-Re(CO)3(4,4′-di-methyl-2,2′-bipyridyl)L+ complex (C2), where L is an electron-withdrawing ancillary ligands which present an intramolecular hydrogen bond (IHB), in a preliminary electrocatalytic reduction of CO2. The C2 complex was synthesized and characterized according to reported methods earlier. The cyclic voltammogram profile for the C2 complex were studied in dichloromethane under inert atmosphere, and it shows a typical behavior for an electrocatalytic process, the C2 complex illustrate the electrochemical reaction mechanism corresponds to an electrochemical–chemical–electrochemical pathway (ECE). Also, a Vitreous Carbon plate used as working electrode was employed and modified by cycling the anodic region of C2 in CH2Cl2 which involve the oxidative redox response for the −NH2 and −OH groups. The voltammogram profile involve shows a polymeric deposit on the plate surface in a CO2 saturated solution (pH=7.0). A strong electrocatalytic discharge of current is obtained with a wave foot of -1.3 V showing that C2 have the potential to be used in electrocatalyst CO2 reduction.

(E)-2-{[(2-Aminopyridin-3-yl)imino]-methyl}-4,6-di-tert-butyl-phenol ( 3: ), a ligand containing an intramolecular hydrogen bond, was prepared according to a previous literature report, with modifications, and was characterized by UV-vis, FTIR, ¹H-NMR, 13C-NMR, HHCOSY, TOCSY and cyclic voltammetry. Computational analyses at the level of DFT and TD-DFT were performed to study its electronic and molecular structures. The results of these analyses elucidated the behaviors of the UV-vis and electrochemical data. Analysis of the transitions in the computed spectrum showed that the most important band is primarily composed of a HOMO→LUMO transition, designated as an intraligand (IL) charge transfer.

Objetivos: Describir las principales características del melanoma cutáneo en el Instituto Nacional de Cancerología, centro de referencia del cáncer, en Bogotá, Colombia. Materiales y métodos: Estudio descriptivo, retrospectivo, de las características demográficas, clínicas e histológicas de los pacientes con diagnóstico de melanoma cutáneo primario, en el Instituto Nacional de Cancerología entre 2006 y 2010. Resultados: Se incluyeron un total de 599 pacientes, de los cuales el 57,4% eran mujeres (n = 344) y el 42,6% hombres (n = 255). La edad media de diagnóstico fue de 60,8 años. La mayoría de los casos fueron procedentes de Bogotá, con el 56,3% (n = 329). Fue más frecuente el área urbana como sitio de residencia habitual (n = 500). La media de frecuencia anual fue de 115 casos nuevos por año. La localización más frecuente fue acral, con el 42,2% (n = 253), seguido de cabeza y cuello (n = 186). Concordando con la localización, el subtipo más frecuente fue el melanoma lentiginoso acral, con el 43,7% (n = 262), seguido por el lentigo maligno, con el 24% (n = 144). En cuanto a la profundidad, se observó una frecuencia igual de melanomas in situ y melanomas con Breslow > 4 mm, ambos con el 19% de los casos. Se encontró que la mayoría de los lentigos malignos, el 75% (n = 108), fueron in situ o con un Breslow ≤ 1 mm; por el contrario, los lentiginosos acrales y los nodulares tuvieron un Breslow > 4 mm con mayor frecuencia (con el 26,3%, n = 69, y el 45,4%, n = 10, respectivamente). El estadio más frecuente fue el III, con el 26,2% de los casos (n = 157). Conclusiones: Se evidenció un mayor porcentaje de melanomas en mujeres y mayor frecuencia de melanomas acrales. Un número importante de pacientes se ubicaron en estado avanzado, por lo que se requieren mayores acciones para la detección temprana del melanoma.

Objectives: To describe the main characteristics of cutaneous melanoma in the National Cancerology Institute, a cancer reference center in Bogota, Colombia. Materials and methods: A descriptive, retrospective study was conducted on the demographic, clinical and histological characteristics of patients diagnosed with primary cutaneous melanoma in the National Cancerology Institute between 2006 and 2010. Results: A total of 599 patients were included, of whom 57.4% were females (n= 344) and 42.6% males (n=255). The mean age at diagnosis was 60.8 years. The majority of cases, 56.3% (n=329), were from Bogota. It was also the most common urban area where the patients had their usual residence (n=500). The mean annual frequency was 115 new cases per year. The most frequent location was acral, with 42.2% (n=253), followed by head and neck (n=186). In accordance with the location, the most common sub-type was acral lentiginous melanoma, with con 43.7% (n=262), followed by lentigo maligna, with 24% (n=144). As regards the depth, a similar frequency was observed for melanomas in situ and melanomas with Breslow >4 mm, both with 19% of the cases. It was found that the large majority of the lentigo maligna, 75% (n=108) were in situ or with a Breslow ≤1 mm. On the other hand, acral lentiginous and nodular melanomas had a higher frequency of Breslow >4 mm (with 26.3% n=69 and 45.4% n=10, respectively). Stage III was the most common stage, with 26.2% (n=157) of the cases. Conclusions: A higher percentage of melanomas were observed in women, as well as a higher frequency of acral melanomas. A signifi cant number of patients were in an advanced stage, thus greater action is required for the early detection of melanoma.