Nanotechnological approaches to address photosensitizers' limitations: towards improved clinical applicability of photodynamic therapy

Photodynamic therapy (PDT) uses a combination of molecular oxygen, light and a photosensitizer (PS) to generate singlet oxygen or reactive oxygen species (ROS), which can eradicate tumoral cells. All currently approved PSs for cancer treatment are molecular PSs. To date, no nanoparticlebased PSs are used clinically although it has widely been shown that nanotechnology may help to improve the properties of molecular PSs; for instance, molecular PSs suffer from some intrinsic limitations that undermine their therapeutic efficacy. In the present minireview, the most critical weaknesses exhibited by molecular PSs are described, and the potential use of nanoparticles (NPs) to address them and to reach the clinics is discussed

Bis(cyanato-κN)bis­(5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine-κN 3)zinc

In the title complex, [Zn(NCO)2(C7H8N4)2], the ZnII ion exhibits a distorted tetra­hedral coordination geometry. The coordination environment is formed by two 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine (dmtp) ligands, coordinated through the N atom in position 3, and two cyanate anions inter­acting by their N atoms. Supra­molecular dimers are generated by stacking inter­actions between the pyrimidine rings of two ligands related by an inversion center [centroid–centroid distance = 3.5444 (18) Å]

4,7-Phenanthrolinium perchlorate-5-methyl-1,2,4-triazolo[1,5-a]pyrimidin-7(4H)-one-water (1/1/2)

The asymmetric unit of the title compound, C12H9N2+·ClO4-·C6H6N4O·2H2O, contains a monoprotonated 4,7-phenanthrolinium (47phen) cation, a perchlorate anion balancing its charge, a neutral molecule of 5-methyl-1,2,4-triazolo[1,5-a]pyrimidin-7(4H)-one (HmtpO) and two interstitial water molecules. In the crystal structure, the acidic H atoms of 47phenH+ and HmtpO form strong hydrogen bonds with the water molecules, which in turn act as hydrogen-bond donors, forming links between them and towards the carbonyl O atom of HmtpO, the non-protonated N atom of 47phen+ and one of the O atoms of the anion.We acknowledge financial support from the Spanish Ministerio de Ciencia y Tecnología (project CTQ2008–00037/PPQ) and from the Junta de Andalucía (research group FQM 195). ABC is grateful for a FPU grant from the Spanish Ministerio de Educación y Ciencia

Bis(7-amino-1,2,4-triazolo[1,5-a]pyrimidin-4-ium) bis­(oxalato-κ2 O 1,O 2)cuprate(II) dihydrate

The structure of the title ionic compound, (C5H6N5)2[Cu(C2O4)2]·2H2O, consists of a centrosymmetric copper(II) oxalate dianion, two monoprotonated mol­ecules of the adenine analog 7-amino-1,2,4-triazolo[1,5-a]pyrimidine (7atp) and two water mol­ecules of crystallization. The CuII ion, located on an inversion center, exhibits a sligthly distorted square-planar coordination geometry, in which two oxalate anions bind in a bidentate fashion. The triazolopyrimidine ligand is protonated at the N atom in position 4, instead of its most basic N atom in position 3. This fact may be explained by the network stability, which is provided through the formation of a two-dimensional wave-like network parallel to (50) by N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds. These nets are further connected via C—H⋯O inter­actions

Concentraciones fosilíferas del Kimmeridgiano Superior en Mazapil, Zacatecas, México: Tafonomía e interpretación paleoambiental

Este último proyecto (Proyecto CGL2012-39835) y el Posgrado de Ciencias de la Tierra, UNAM; facilitaron la realización de una estancia de investigación de la primera autora en la Facultad de Ciencias de la Universidad de Granada. Se reconocen las aportaciones de los revisores, Sara Alicia Quiroz Barroso y Miguel Agustín Téllez Duarte. Se agradece a Marco Antonio Argáez Martínez su apoyo en campo, elaboración de láminas delgadas y superficies pulidas.Como aproximación preliminar al estudio detallado de concentraciones fosilíferas en el Jurásico Superior de México, se analizan las registradas en una sucesión de 410 cm de espesor de la Formación La Caja, perteneciente al Kimmeridgiano tardío, la cual aflora en el Cañón de San Matías. Mazapil, Zacatecas. Las observaciones litoestratigráficas, sedimentológicas, paleontológicas, bioestratigráficas y tafonómicas se realizaron estrato a estrato con resolución centimétrica. El estudio taxonómico y bioestratigráfico se centró en las asociaciones de macroinvertebrados, esencialmente ammonites. El análisis tafonómico se realizó sobre 1175 restos cuya composición responde a la de comunidades neríticas (ammonites 53 %, aptychi 27 %, bivalvos 18 % y gasterópodos 2 %) que se depositaron en profundidades menores que las de implosión para las carcasas de ammonites. En ámbito de plataforma sin evidencias de relieves pronunciados, se interpreta un contexto eco- sedimentario de baja energía (floatstone-wackestone de bioclastos y wackestone de radiolarios; existen parches locales de packstone), con depósito de limolitas incipiente e irregularmente calcáreas asociadas a un ambiente de plataforma sin evidencias de relieves pronunciados. Son características la ausencia de superficies de erosión expresivas, deslizamientos sinsedimentarios, aportes exóticos, y estructuras sedimentarias inequívocamente relacionadas con oleaje, así como el predominio de laminaciones paralelas y/o suavemente oblicuas. Las condiciones ecológicas incluyeron fondos disaeróbicos-poikiloaeróbicos con escaso registro de bentos in situ, y ferruginización frecuente relacionada con concentraciones de materia orgánica, así como inestabilidades en la columna de agua que afectarían a las comunidades de organismos pelágicos y bentónicos generando incrementos en la exportación de restos al fondo. Las concentraciones fosilíferas registradas son más expresivas hacia la base y techo de los estratos, son discontinuas y su configuración macroscópica responde a la de pavimentos y capas de conchas (shell beds). Se interpretan como eventitas distales resultantes de procesos con energía efectiva variable (huracanes, tormentas, corrientes de fondo ligadas a tormentas, aventamientos), cuya incidencia alcanzó sectores proximales de la plataforma externa en torno al nivel de base de tormentas. Secuencias de redepósito incompletas se relacionan con eventos de mayor energía efectiva y sobreimposición de horizontes. El patrón de la secuencia de redepósito tipo responde a eventos energéticos, disipación progresiva pero rápida de la energía, y retorno a condiciones eco-sedimentarias normales para el sector según el registro estratigráfico. La dinámica eco-sedimentaria propuesta para la sucesión estudiada en el perfil Cañón de San Matías responde a rupturas de equilibrio ambiental con periodos de recurrencia de rango inferior al de la resolución bioestratigráfica en ámbito de plataforma, sin evidencias de relieves próximos, ni de la existencia de ruptura de plataforma ni talud continental en el área, durante el intervalo estudiado del Kimmeridgiano tardío.A 410 cm thick succession of late Kimmeridgian deposits belonging to the La Caja Fm. has been analyzed in the San Matias Canyon as preliminary approach to the study of fossil concentrations in the Upper Jurassic of Mexico. Lithostratigraphic, sedimentologic, taxonomic, biostratigraphic and taphonomic observations based on a bed-by-bed sampling with centimeter scale resolution. Taxonomic and biostratigraphic analyses focused on macroinvertebrate assemblages, mainly ammonites. The taphonomic analysis applied to 1175 fossil remains of neritic communities (ammonites 53 %, aptychi 27 %, bivalves 18 % and gastropods 2 %), accumulated in depths lesser than those estimated for implosion of ammonite carcasses. Within a shelf-area without evidence of high-irregular seabeds, an eco-sedimentary context of low energy agrees with depositional conditions resulting in lithofacies of floatstone-wackestone of bioclasts and wackestone of radiolaria, together with local patches of packstone and the intercalation of calcareous siltstone. In addition, low energy conditions are in accordance with the absence of expressive erosion surfaces, synsedimentary sliding, exotic clasts, and sedimentary structures typically related to wave action, as well as with the common occurrence of parallel and/or subtle oblique laminations. Ecological conditions included disaerobic-poikiloaerobic seabeds with rare record of benthos in situ, common ferruginization related to organic matter-rich sediments, and water column instabilities affecting pelagic and benthic communities resulting in increased accumulation of skeletals remains on the seabed. The recorded fossiliferous concentrations are more evident to the bottom and top surfaces of beds, they are discontinuous, and their macroscopic biofabric corresponds to pavements and shell beds. These fossil-rich horizons are interpreted as distal eventites resulting from turbulence events of variable effective energy (hurricanes, storms, storm-forced bottom currents, and winnowing), the influence of which reached proximal sectors of the outer shelf at depths close to the storm wave base. Incomplete sequences related to reworking are interpreted as resulting from events of higher-than-background effective energy and over-imposition of depositional horizons. The pattern of the type sequence of re-deposition related to the succession of higher-than-background energy events, progressive but rapid dissipation of energy, and the return to background eco-sedimentary conditions. The eco-sedimentary dynamics proposed for the succession analyzed at the San Matias Canyon, Mazapil, Zacatecas, indicates pulses of paleoenvironmental instability within a neritic shelf, and with recurrence periods shorter than the range of biostratigraphic resolution. No evidence of high-irregular seabeds has been found in the surrounding area nor the occurrence of the shelf-break and slope in the area during the investigated stratigraphic interval of late Kimmeridgian age.Esta investigación fue apoyada por los proyectos UNAM-DGAPA-PAPIIT IN105311-3, IN102016, y el Proyecto CGL2012-39835 del Ministerio de Industria Economía y Competitividad (MINECO), España

First records of the iceryine scale insects \u3ci\u3eCrypticerya brasiliensis\u3c/i\u3e (Hempel) and \u3ci\u3eCrypticerya genistae\u3c/i\u3e (Hempel) (Hemiptera: Monophlebidae) for Colombia

Abstract. Crypticerya brasiliensis (Hempel) and Crypticerya genistae (Hempel) (Hemiptera: Monophlebidae: Iceryini) are herein reported for the fi rst time in Colombia. The above two species and Crypticerya multicicatrices Kondo and Unruh and Crypticerya zeteki (Cockerell) are briefl y diagnosed based on the adult females. The presence of C. zeteki in Colombia is confi rmed and a key to the adult females of species of the tribe Iceryini reported in Colombia is provided. Resumen. Se reportan por primera vez a Crypticerya brasiliensis (Hempel) y Crypticerya genistae (Hempel) (Hemiptera: Monophlebidae: Iceryini) en Colombia. Las dos especies arriba mencionadas junto con Crypticerya multicicatrices Kondo y Unruh y Crypticerya zeteki (Cockerell) se diagnostican brevemente con base en morfología de las hembras adultas. Se confi rma la presencia de C. zeteki en Colombia y se provee una clave para las hembras adultas de las especies de la tribu Iceryini registradas en Colombia

Steric hindrance, ligand ejection and associated photocytotoxic properties of ruthenium(II) polypyridyl complexes

Two ruthenium(II) polypyridyl complexes were prepared with the {Ru(phen)2}2+ moiety and a third sterically non-hindering bidentate ligand, namely 2,2'-dipyridylamine (dpa) and N-benzyl-2,2'-dipyridylamine (Bndpa). Hence, complexes [Ru(phen)2(dpa)](PF6)2 (1) and [Ru(phen)2(Bndpa)](PF6)2 (2) were characterized and their photochemical behaviour in solution (acetonitrile and water) was subsequently investigated. Compounds 1 and 2, which do not exhibit notably distorted octahedral coordination environments, contrarily to the homoleptic 'parent' compound [Ru(phen)3](PF6)2, experience two-step photoejection of the dpa and Bndpa ligand upon irradiation (1050-430 nm) for several hours. DNA-binding studies revealed that compounds 1 and 2 affect the biomolecule differently upon irradiation; while 2 solely modifies its electrophoretic mobility, complex 1 is also capable of cleaving it. In vitro cytotoxicity studies with two cancer-cell lines, namely A549 (lung adenocarcinoma) and A375 (melanoma), showed that both 1 and 2 are not toxic in the dark, while only 1 is significantly cytotoxic if irradiated, 2 remaining non-toxic under these conditions

The effect of potential supramolecular-bond promoters on the DNA-interacting abilities of copper-terpyridine compounds.

Three copper(II) coordination compounds have been prepared from three different 2,2′:6′,2′′-terpyridine-based ligands, which have been selected to investigate the potential role of supramolecular interactions on the DNA-interacting and cytotoxicity properties of the corresponding metal complexes. Hence, the ligands 4′-((naphthalen-2-yl)methoxy)-2,2′:6′,2′′-terpyridine (Naphtpy) and 4′-((1H-benzo[d]imidazol-2-yl)methoxy)-2,2′:6′,2′′-terpyridine (Bimztpy) have been synthesized from commercially-available 4′-chloro-2,2′:6′,2′′-terpyridine (Cltpy), and their copper(II) complexes have been obtained by reaction with copper(II) nitrate. The DNA-interacting abilities of the corresponding compounds [Cu(Cltpy)(H2O)(NO3)2] (1), [Cu(naphtpy)(NO3)(H2O)](NO3)(MeOH) (2) and [Cu(bimztpy)(NO3)(H2O)](NO3) (3) have been investigated using different techniques, and cytotoxicity assays with several cancer cell lines have revealed interesting features, viz. the more efficient complex is 2, which although it does not act as a DNA cleaver, displays the most effective DNA-interacting and cytotoxic properties, compared to 1 and 3

Sistema de acciones con enfoque bioético a cuidadores de pacientes oncogeriátricos con ingreso domiciliario

Introduction: the first cause of death in elderly are oncological diseases, which require quality in the performance of the caregiver with a bioethical approach at home.Objective: to design a system of actions with a bioethical focus for caregivers of oncogeriatric patients with advanced stages of the disease and home admission.Methods: a descriptive, transversal and observational study was carried out at the "Marta Abreu de Estévez" University Polyclinic in the Municipality of Santa Clara from September 2018 to June 2019. The universe was made up of the 12 primary caretakers of oncogeriatric patients in an advanced stage of the disease admitted to the home. In order to obtain the information, documentary analysis and the application of a survey were used to measure knowledge in caregivers related to care with a bioethical approach, prior informed consent.Results: predominantly female between 50 and 59 years old, and low and high level of schooling. Learning needs were identified for palliative care with bioethical approach at home, which allowed the design of the system of actions to face this stage of life.Conclusions: Insufficient instruction was identified in caregivers about bioethical knowledge in the care of the elderly in advanced stages with oncological disease. It was pertinent to design a system of psycho-educational actions to be implemented by the health team that would contribute to the performance of the caregivers with greater quality and would respect bioethical principles during life and human dignity as the most sacred of rights.Introducción: la primera causa de muerte en los gerontes son las enfermedades oncológicas, que requieren de calidad en la actuación del cuidador con enfoque bioético en el domicilio.Objetivo: diseñar un sistema de acciones con enfoque bioético para cuidadores de pacientes oncogeriátricos con estado avanzado de la enfermedad e ingreso domiciliario.Métodos: se realizó un estudio descriptivo, transversal y observacional en el Policlínico Universitario “Marta Abreu de Estévez” del Municipio Santa Clara desde septiembre de 2018 a junio de 2019. El universo estuvo constituido por los 12 cuidadores primarios de pacientes oncogeriátricos en fase avanzada de la enfermedad ingresados en el hogar. Para obtener la información se utilizaron el análisis documental y la aplicación de encuesta para medir conocimientos en cuidadores relacionados con la atención con enfoque bioético, previo consentimiento informado.Resultados: predominó el sexo femenino entre 50 y 59 años, y nivel bajo y superior de escolaridad. Se identificaron necesidades de aprendizaje para la atención paliativa con enfoque bioético en el domicilio, lo que permitió el diseño del sistema de acciones para enfrentar esta etapa de la vida.Conclusiones: se identificaron insuficiencias de instrucción en los cuidadores sobre conocimientos bioéticos en la atención al adulto mayor en estadio avanzado con enfermedad oncológica. Fue pertinente el diseño de un sistema de acciones psicoeducativo a implementar por el equipo de salud que contribuya al desempeño de los cuidadores con mayor calidad y respete los principios bioéticos durante la vida y la dignidad humana como el más sagrado de los derechos