Perspectives of Breast Cancer Thermotherapies

International audienceIn this article, the use of different types of thermotherapies to treat breast cancer is reviewed. While hyperthermia is most commonly used as an adjuvant in combination with radiotherapy, chemotherapy, targeted therapy or cryotherapy to enhance the therapeutic effect of these therapies, thermoablation is usually carried out alone to eradicate small breast tumors. A recently developed thermotherapy, called magnetic hyperthermia, which involves localized heating of nanoparticles under the application of an alternating magnetic field, is also presented. The advantages and drawbacks of these different thermotherapies are highlighted

Nanomaterials as Ultrasound Theragnostic Tools for Heart Disease Treatment/Diagnosis.

A variety of different nanomaterials (NMs) such as microbubbles (MBs), nanobubbles (NBs), nanodroplets (NDs), and silica hollow meso-structures have been tested as ultrasound contrast agents for the detection of heart diseases. The inner part of these NMs is made gaseous to yield an ultrasound contrast, which arises from the difference in acoustic impedance between the interior and exterior of such a structure. Furthermore, to specifically achieve a contrast in the diseased heart region (DHR), NMs can be designed to target this region in essentially three different ways (i.e., passively when NMs are small enough to diffuse through the holes of the vessels supplying the DHR, actively by being associated with a ligand that recognizes a receptor of the DHR, or magnetically by applying a magnetic field orientated in the direction of the DHR on a NM responding to such stimulus). The localization and resolution of ultrasound imaging can be further improved by applying ultrasounds in the DHR, by increasing the ultrasound frequency, or by using harmonic, sub-harmonic, or super-resolution imaging. Local imaging can be achieved with other non-gaseous NMs of metallic composition (i.e., essentially made of Au) by using photoacoustic imaging, thus widening the range of NMs usable for cardiac applications. These contrast agents may also have a therapeutic efficacy by carrying/activating/releasing a heart disease drug, by triggering ultrasound targeted microbubble destruction or enhanced cavitation in the DHR, for example, resulting in thrombolysis or helping to prevent heart transplant rejection

Glioblastoma Treatments: An Account of Recent Industrial Developments

The different drugs and medical devices, which are commercialized or under industrial development for glioblastoma treatment, are reviewed. Their different modes of action are analyzed with a distinction being made between the effects of radiation, the targeting of specific parts of glioma cells, and immunotherapy. Most of them are still at a too early stage of development to firmly conclude about their efficacy. Optune, which triggers antitumor activity by blocking the mitosis of glioma cells under the application of an alternating electric field, seems to be the only recently developed therapy with some efficacy reported on a large number of GBM patients. The need for early GBM diagnosis is emphasized since it could enable the treatment of GBM tumors of small sizes, possibly easier to eradicate than larger tumors. Ways to improve clinical protocols by strengthening preclinical studies using of a broader range of different animal and tumor models are also underlined. Issues related with efficient drug delivery and crossing of blood brain barrier are discussed. Finally societal and economic aspects are described with a presentation of the orphan drug status that can accelerate the development of GBM therapies, patents protecting various GBM treatments, the different actors tackling GBM disease, the cost of GBM treatments, GBM market figures, and a financial analysis of the different companies involved in the development of GBM therapies

Ultrasound and nanomaterial: an efficient pair to fight cancer

Ultrasounds are often used in cancer treatment protocols, e.g. to collect tumor tissues in the right location using ultrasound-guided biopsy, to image the region of the tumor using more affordable and easier to use apparatus than MRI and CT, or to ablate tumor tissues using HIFU. The efficacy of these methods can be further improved by combining them with various nano-systems, thus enabling: (i) a better resolution of ultrasound imaging, allowing for example the visualization of angiogenic blood vessels, (ii) the specific tumor targeting of anti-tumor chemotherapeutic drugs or gases attached to or encapsulated in nano-systems and released in a controlled manner in the tumor under ultrasound application, (iii) tumor treatment at tumor site using more moderate heating temperatures than with HIFU. Furthermore, some nano-systems display adjustable sizes, i.e. nanobubbles can grow into micro-bubbles. Such dual size is advantageous since it enables gathering within the same unit the targeting properties of nano bubbles via EPR effect and the enhanced ultrasound contrasting properties of micro bubbles. Interestingly, the way in which nano-systems act against a tumor could in principle also be adjusted by accurately selecting the nano-system among a large choice and by tuning the values of the ultrasound parameters, which can lead, due to their mechanical nature, to specific effects such as cavitation that are usually not observed with purely electromagnetic waves and can potentially help destroying the tumor. This review highlights the clinical potential of these combined treatments that can improve the benefit/risk ratio of current cancer treatments

Análisis de la evolución hidrogeoquímica y diagnóstico de procesos de biomineralización controlada en agua subterránea : caso Pozo UPTC, Sogamoso

1 recurso en línea (103 páginas) : ilustraciones color, figuras, tablas.Geomicrobiology has special interest in the role played by microorganisms in chemical cycles of chemical elements, including iron. Therefore, the incidence of bacteria in the absorption and reduction of elements of interest has been studied; Experimental studies have also been carried out on the use of catabolic processes of different bacteria as a bioremediation technique during the treatment of groundwater. However, the design of a formulation for the purification of this type of water, it is advisable to know the dynamics of the flow and the great part of the rock-water interaction processes that have influenced the chemical tool of the underground resource. In accordance with the above, it was pointed out the hydrogeochemical processes that have intervened in the evolution of the groundwater captured in the UPTC well, Sogamoso, and the iron and manganese removal capacity in the well water samples was evaluated from the exploitation of bacterial biomineralization processes. To do this, the sampling of eleven (11) samples of groundwater was carried out for the analysis of physicochemical parameters and the determination of the concentrations of the ionic content of interest. The processing of the information was done through hydrogeochemical diagrams (Piper, Stiff and Schoeller-Berkaloff) and some binary graphs that provide information on local conditions; and in a complementary manner, two (2) multivariate statistical methods were applied to quantitatively verify the results obtained through the hydrogeochemical analysis. In a complementary manner, the isotopic content of four (4) of the samples was analyzed to identify the possible recharge zones and, in this way, the preliminary hydrogeological model was constructed for the study area. The integration of this information allowed to define part of the natural and exogenous constituents to the dynamics of the underground flow. Additionally, an experimental method of bioremediation based on the biomineralization mechanisms, typical of the Magnetotactic Bacteria (MTB's) was tested, from which it was possible to eliminate part of the high content of Fe and Mn in the well waters. For this, it was required of the prospection of MTB at regional level, the isolation, the characterization and the verification of the magnetic response of the microorganisms, to finally, perform a process of inoculation of samples enriched with MTB in well water samples. This research for the opening to the future development of methodologies that include the use of microorganisms with magnetic properties and the use of bacterial biomineralization processes for the removal of medical crystals during the treatment of groundwater.La geomicrobiología tiene especial interés en el papel que desempeñan los microorganismos en los ciclos biológicos de los elementos químicos, entre ellos el hierro. Por ello, se ha estudiado la incidencia de bacterias en la absorción y reducción de elementos de interés; asimismo se han realizado estudios experimentales acerca de la utilización de los procesos catabólicos de diferentes bacterias como técnica de biorremediación durante el tratamiento de aguas subterráneas. No obstante, previo a cualquier formulación para la depuración de este tipo de aguas, es recomendable conocer la dinámica del flujo y gran parte de los procesos de interacción roca-agua que han incidido en la composición química del recurso subterráneo. Conforme a lo anterior, se analizaron los procesos hidrogeoquímicos que han intervenido en la evolución del agua subterránea captada en el pozo UPTC, Sogamoso, y se evaluó la capacidad de remoción de hierro y manganeso en muestras de agua del pozo a partir del aprovechamiento de los procesos de biomineralización bacteriana. Para ello, se realizó la toma de once (11) muestras de agua subterránea para el análisis de parámetros fisicoquímicos y la determinación de las concentraciones del contenido iónico de interés. El procesamiento de la información se realizó a través de diagramas hidrogeoquímicos (Piper, Stiff y Schoeller-Berkaloff) y algunos gráficos binarios que aportaran información de las condiciones locales; y de manera complementaria, se aplicaron dos (2) métodos estadísticos multivariantes para comprobar cuantitativamente los resultados obtenidos a través del análisis hidrogeoquímico. De manera complementaria, se analizó el contenido isotópico de cuatro (4) de las muestras, para identificar las posibles zonas de recarga y de esta manera construir el modelo hidrogeológico preliminar para el área de estudio. La integración de esta información permitió definir parte de los constituyentes naturales y exógenos a la dinámica del flujo subterráneo. Adicionalmente, se ensayó un método experimental de biorremediación basado en los mecanismos de biomineralización, propios de las bacterias Magnetotácticas (MTB’s), a partir del cual se logró remover parte del alto contenido de Fe y Mn en las aguas del pozo. Para ello, se requirió de la prospección de MTB’s a nivel regional, el aislamiento, la caracterización y la comprobación de la respuesta magnética de los microorganismos, para finalmente, realizar un proceso de inoculación de muestras enriquecidas con MTB´s en muestras de agua del pozo. Esta investigación da apertura al futuro desarrollo de metodologías que incluyan la utilización de microorganismos con propiedades magnéticas y el uso de procesos de biomineralización bacteriana para la remoción de elementos metálicos durante el tratamiento de aguas subterráneas.Bibliografía y webgrafía: páginas 94-103.PregradoIngeniero Geólog

Natural Metallic Nanoparticles for Application in Nano-Oncology

Here, the various types of naturally synthesized metallic nanoparticles, which are essentially composed of Ce, Ag, Au, Pt, Pd, Cu, Ni, Se, Fe, or their oxides, are presented, based on a literature analysis. The synthesis methods used to obtain them most often involve the reduction of metallic ions by biological materials or organisms, i.e., essentially plant extracts, yeasts, fungus, and bacteria. The anti-tumor activity of these nanoparticles has been demonstrated on different cancer lines. They rely on various mechanisms of action, such as the release of chemotherapeutic drugs under a pH variation, nanoparticle excitation by radiation, or apoptotic tumor cell death. Among these natural metallic nanoparticles, one type, which consists of iron oxide nanoparticles produced by magnetotactic bacteria called magnetosomes, has been purified to remove endotoxins and abide by pharmacological regulations. It has been tested in vivo for anti-tumor efficacy. For that, purified and stabilized magnetosomes were injected in intracranial mouse glioblastoma tumors and repeatedly heated under the application of an alternating magnetic field, leading to the full disappearance of these tumors. As a whole, the results presented in the literature form a strong basis for pursuing the efforts towards the use of natural metallic nanoparticles for cancer treatment first pre-clinically and then clinically

Nano dimensions/adjuvants in COVID-19 vaccines

A favorable outcome of the COVID-19 crisis might be achieved with massive vaccination. The proposed vaccines contain several different vaccine active principles (VAP), such as inactivated virus, antigen, mRNA, and DNA, which are associated with either standard adjuvants or nanomaterials (NM) such as liposomes in Moderna's and BioNTech/Pfizer's vaccines. COVID-19 vaccine adjuvants may be chosen among liposomes or other types of NM composed for example of graphene oxide, carbon nanotubes, micelles, exosomes, membrane vesicles, polymers, or metallic NM, taking inspiration from cancer nano-vaccines, whose adjuvants may share some of their properties with those of viral vaccines. The mechanisms of action of nano-adjuvants are based on the facilitation by NM of targeting certain regions of immune interest such as the mucus, lymph nodes, and zones of infection or blood irrigation, the possible modulation of the type of attachment of the VAP to NM, in particular VAP positioning on the NM external surface to favor VAP presentation to antigen presenting cells (APC) or VAP encapsulation within NM to prevent VAP degradation, and the possibility to adjust the nature of the immune response by tuning the physico-chemical properties of NM such as their size, surface charge, or composition. The use of NM as adjuvants or the presence of nano-dimensions in COVID-19 vaccines does not only have the potential to improve the vaccine benefit/risk ratio, but also to reduce the dose of vaccine necessary to reach full efficacy. It could therefore ease the overall spread of COVID-19 vaccines within a sufficiently large portion of the world population to exit the current crisis

Iron oxide nanoparticles as multimodal imaging tools

International audienceIn medicine, obtaining simply a resolute and accurate image of an organ of interest is a real challenge. To achieve this, it has recently been proposed to use combined methods in which standard imaging (MRI, PAI, CT, PET/SPEC, USI, OI) is carried out in the presence of iron oxide nanoparticles, thus making it possible to image certain tissues/cells through the specific targeting of these nanoparticles, hence resulting in improved imaging contrast and resolution. Here, the advantages and drawbacks of these combined methods are presented as well as some of their recent medical applications

Iron oxide nanoparticles for therapeutic applications

In nanomedicine, iron oxide nanoparticles are at an advanced stage, being commercialized for cancer treatment and iron-deficiency anemia treatment. Their therapeutic efficacy comes from their ability to target a tissue, activate a drug, locally produce a temperature increase following (or not) the application of an external source of energy, modify genes or activate various biological materials, or replace diseased cells by stem cells. Owing to these various mechanisms of action, they can potentially be used for treating a whole range of different diseases, making them more appealing than conventional drugs that target a more limited number of indications

Applications of magnetotactic bacteria and magnetosome for cancer treatment: A review emphasizing on practical and mechanistic aspects

Magnetotactic bacteria (MTB) synthesize iron oxide (Fe$_{3}$O$_{4}$) nanoparticles (NPs), called magnetosomes, with large sizes leading to a ferrimagnetic behavior and a stable magnetic moment at physiological temperature, a chain structure that prevents NP aggregation and promotes uniform NP distribution, and a mineral core of magnetite/maghemite composition, which can be stabilized by an organic coating. Such properties can favor magnetosome administration to humans under certain optimized non-toxic conditions of fabrication. In this review, I describe the fabrication methods, physico-chemical properties, and the anti-tumor activity of different types of MTB/magnetosome preparations, highlighting the bio-compatibility and excellent anti-tumor activity of purified non-pyrogenic magnetosome minerals stabilized by a synthetic chemical compound