Marcadores citogenéticos aplicados en biomedicina = Cytogentic biomarkers applied in biomedicine

Cuando se pretende identificar una determinada exposición a una sustancia exógena al organismo se utilizan biomarcadores que nos permitan confirmar esta exposición. En el caso de que la exposición provoque un efecto nocivo en el material genético, el interés se centra en biomarcadores genotóxicos. Si el efecto en el material genético se traduce en cambios en la estructura o en el número de cromosomas observables y cuantificables mediante técnicas citogenéticas, estos cambios se podrán emplear como biomarcadores citogenéticos. De hecho, los biomarcadores citogenéticos son criterios de valoración frecuentemente utilizados en estudios poblacionales. Su sensibilidad para la medición de exposición a agentes genotóxicos y el papel de algunos biomarcadores como indicadores tempranos del riesgo de cáncer han contribuido a este éxito. Existen distintos biomarcadores citogenéticos según el propósito del estudio, entre ellos, los generalmente más utilizados son los micronúcleos, los intercambios de cromátidas hermanas y las aberraciones cromosómicas. Entre los agentes químicos a los que los humanos pueden estar expuestos se encuentran aquellos que componen el tabaco. Un elevado número de compuestos presentes en el tabaco han sido clasificados por la Agencia Internacional de Investigación sobre el Cáncer (IARC) como cancerígenos o posibles cancerígenos para el ser humano. La evaluación mediante técnicas citogenéticas del daño causado en el ADN por la exposición a estos compuestos es de gran utilidad para confirmar los efectos perjudiciales del tabaco sobre el material genético. Otro tipo de agentes, concretamente los presentes en las pinturas usadas como aerosoles, causaron un grave impacto en la salud de ciertos trabajadores de industrias textiles in la región de Valencia (España). Este suceso fue clasificado como el “syndrome de Ardystil” y después del accidente se pensó en llevar a cabo un plan de vigilancia de la salud de la gente afectada. Con el fin de evaluar la posible persistencia de alteración en los cromosomas, se realizó la técnica de intercambio de cromátidas hermanas. La radiación ionizante es otro agente que provoca lesiones en el material genético de las células. En determinados casos estas lesiones forman parte del efecto deseado de las radiaciones, como en la radioterapia, sin embargo, en estos procedimientos de tratamiento o en determinadas situaciones de diagnóstico médico con radiaciones ionizantes se pueden ocasionar efectos indeseados con repercusiones sobre la salud de los individuos. Con el propósito de evitar o mitigar estos efectos indeseados de la radiación ionizante se han investigado diversos productos sintéticos y naturales, con un interés creciente por estos últimos. Mediante los biomarcadores citogenéticos como las aberraciones cromosómicas podemos evaluar el daño que la radiación causa en el ADN de las células y la posible disminución ofrecida por parte de los compuestos llamados radioprotectores. De forma semejante podemos evaluar la toxicidad que los compuestos objeto de estudio pueden ejercer por sí mismos. Uno de los grupos con más interés para su aplicación como radioprotectores es el grupo de los polifenoles. En relación con la exposición a la radiación ionizante, las técnicas citogenéticas pueden ser utilizadas como una herramienta para evaluar la posible radiosensibilidad de cada individuo ya que se sabe que en los seres humanos se exhibe un rango de variación interindividual en la frecuencia y severidad de los efectos aparecidos después de la exposición a las radiaciones ionizantes. Esta medida podría ayudar a evaluar el riesgo individual de sujetos expuestos a tratamientos con radiaciones ionizantes con la posibilidad de un ajuste más personalizado de las dosis o como una medida preventiva adicional en trabajadores expuestos a radiación ionizante. Además, la técnica citogenética desarrollada para la evaluación de la radiosensibilidad individual permite evaluar in vitro, cómo determinados compuestos, que pueden estar presentes de forma simultánea a la radiación, son capaces de modificar la respuesta de las células a la misma. En los estudios de genotoxicidad, se analizan los biomarcadores de aberraciones cromosómicas, intercambio de cromátidas hermanas, índice mitótico e índice de proliferación. Concretamente, en el estudio de individuos fumadores y afectados por el síndrome Ardystil, del análisis del intercambio de cromátidas hermanas se extrajeron dos parámetros, las células con un número de intercambios superior al percentil 95 y un ratio que analiza la concentración de intercambios en un cromosoma en lugar de distribuilos uniformemente en los 46 cromosomas. Resulta imprescindible la diferenciación del número de ciclos celulares que han experimentado los linfocitos, por lo que al principio del cultivo se debe añadir una sustancia que permitirá diferenciar la primera, segunda y tercera división mediante la técnica de tinción concreta de Fluorescencia más Giemsa. Para los estudios del tabaco y síndrome de Ardystil se procesaron las muestras de sangre periférica obtenidas de los sujetos estudiados y se procedió al análisis citogenético para el estudio del biomarcador de intercambio de cromátidas hermanas. Para el estudio de la genotoxicidad de los polifenoles de la curcumina y el trans-resveratrol, ambos compuestos se añadieron por separado y en distintas concentraciones un determinado tiempo antes de empezar el cultivo de las muestras. El análisis citogenético incluyó el estudio de los biomarcadores de aberraciones cromosómicas, intercambio de cromátidas hermanas y los índices mitótico y de proliferación. En los estudios de radioprotección, se utilizaron dos técnicas citogenéticas. Por una parte, el ensayo de cromosomas dicéntricos, basado en la irradiación con radiación ionizante de muestras de sangre periférica humana pre-incubadas con curcumina y trans-resveratrol, cultivo de las mismas y análisis citogenéticos de las aberraciones cromosómicas para el recuento de cromosomas dicéntricos considerados biomarcadores de daño radioinducido. Por otra parte, la técnica de condensación prematura de cromosomas, basada en la irradiación con radiación ionizante de linfocitos aislados de sangre periférica humana previamente incubadas con diferentes concentraciones de curcumina y trans-resveratrol, fusión con células mitóticas de ovario de hámster chino, cultivo y análisis citogenético del daño radioinducido en forma de fragmentos cromosómicos. En los estudios de radiosensibiliad, se empleó el ensayo G2 para dos aplicaciones distintas. Por un lado, el ensayo de radiosensibilidad en fase G2 aplicado a la evaluación de la radiosensibilización in vitro de compuestos químicos, concretamente curcumina y trans-resveratrol, para estudiar si ambas sustancias son capaces de modificar la radiosensibilidad en fase G2 de linfocitos humanos. Por otro lado, el ensayo de radiosensibilidad en fase G2 aplicado a un caso clínico para la evaluación de la radiosensibilidad individual de un paciente con efectos secundarios adversos tras un tratamiento de radiología intervencionista. De esta forma la paciente puede ser clasificada como “hiperradiosensible”, “radiosensible”, “normal” o “radioresistente” según la clasificación propuesta por Terzoudi y Pantelias (2011). Mediante el empleo de biomarcadores citogenéticos es posible evaluar como diferentes agentes químicos y físicos causan una alteración del material cromosómico. El análisis de los biomarcadores utilizados para evaluar la genotoxicidad del tabaco y de componentes utilizados en aerografía textil sin condiciones de prevención de riesgos laborales (“Síndrome de Ardystil”) permitió observar un aumento estadísticamente significativo de la afectación del material genético en individuos fumadores así como comprobar que esta afectación ya no estaba presente en sujetos afectados por el “síndrome de Ardystil” pasados diez años del suceso. El estudio in vitro de las propiedades genotóxicas, radioprotectoras y radiosensibilizantes de los compuestos polifenólicos curcumina y trans-resveratrol pone de manifiesto la versatilidad con la que actúan estos compuestos dependiendo de las concentraciones utilizadas, el momento del ciclo celular en el que son absorbidos por las células y las condiciones a las que son sometidas las muestras. La aplicación del ensayo de radiosensibilidad individual en fase G2 del ciclo celular a una paciente con efectos secundarios tras una intervención mediada por radiación ionizante es un primer paso para la aplicación futura de esta técnica citogenética en medicina preventiva. Tanto pacientes como trabajadores sometidos a tratamientos con radiaciones ionizantes dispondrían de una herramienta adicional para mejorar la individualización del tratamiento o para la mejor prevención de riesgos laborales.Several biomarkers are used to identify and confirm human exposure to exogenous compounds. In cases where the exposure has an adverse effect on the genetic material, the interest is focused on the genotoxic biomarkers. If this effect on the genetic material results in changes in the chromosomal structure or number, which are observable and quantifiable by cytogenetic techniques, these changes can be used as biomarkers. Nowadays, cytogenetic biomarkers are endpoints frequently used in population studies; their sensitivity for measurement of exposure to genotoxic agents and the role of some of the cytoenetic biomarkers as early predictors of cancer risk have contributed to this success. Different cytogenetic biomarkers can be used according to the purpose of the study. Those generally used are micronucleus, sister chromatid exchanges and chromosomal aberrations. Among the wide variety of chemicals to which humans can be exposed, tobacco is a very important. A large number of compounds from tobacco and tobacco smoke have been classified by the International Agency for Research on Cancer (IARC) as carcinogens or probably carcinogens for humans. The DNA damage assessed by cytogenetic techniques is a useful tool in order to confirm the harmful effects of tobacco on the genetic material. Other types of chemicals, present in aerosol paints, caused a severe health impact in some workers in the textil painting factories in the region of Valencia (Spain). This outbreak was classified as the “Ardystil syndrome” and subsequently it was decided to carry out a health surveillance program in affected people. In order to evaluate a persistent alteration in chromosomes, the sister chromatid exchange technique was carried out. Ionizing radiation is another agent responsible for genetic damage. In specific situations these lesions in the DNA are an expected effect of radiation, such as radiotherapy. However, these methods of clinical treatment or medical diagnosis involving ionizing radiation can cause undesired effects involving an impact on human health. In order to avoid or mitigate these undesired effects many synthetic or natural products have been proposed, with an increasing interest in the latter. Cytogenetic biomarkers such as chromosomal aberrations can highlight the DNA damage in cells caused by radiation and therefore the possible damage reduction provided by compounds usually called radioprotectors. Similarly, the genotoxicity of these compounds which are under study can be evaluated. One of the groups of natural compounds with a major interest for application as radioprotectors is the polyphenols group. Related to ionizing radiation exposure, cytogenetic techniques can be used as a useful tool to evaluate the individual radiosensitivity because it is known that humans exhibit a range of individual variation in the frequency and severity of effects occurring after ionizing radiation exposure. This measure could help to assess the individual risk of subjects exposed to ionizing radiation, thus a better dose adjustment in case of medical intervention or an additional preventive measure in subjects working with radiation. In addition, the cytogenetic technique for the assessment of individual radiosensitivity can be used to evaluate, in vitro, whether certain compounds, which may be present simultaneously with radiation, are capable of modifying the cell response. In genotoxicity studies, the biomarkers analyzed were the chromosomal aberrations, sister chromatid exchanges, mitotic index and the proliferation index. From the analysis of sister chromatid exchanges, in the tobacco and “Ardystil syndrome” study, it was calculated the parameter of cells with a frequency of exchanges higher than the 95 percentil and a ratio which analyzed the clustering of exchanges in one chromosome instead of being uniformingly distributed among the metaphase. In these studies it is essential to differentiate the number of cell cycles of the lymphocytes; for this reason, at the beginning of the cell cultures a substance should be added which allows for the differentiation of the first, second and third cell divisions with the Fluorescence plus Giemsa staining. For the tobacco and “Ardystil syndrome” studies, human peripheral blood samples were processed for the cytogenetic analysis of the sister chromatid exchanges biomarker. In the study of the genotoxicity of the polyphenols curcumin and trans-resveratrol, blood samples were incubated with different concentrations of both compounds before starting the culture. Cytogenetic analysis included the study of biomarkers such as chromosomal aberrations, sister chromatid exchanges and mitotic and proliferation index. In the radioprotection studies, two different techniques were carried out. On the one hand, the dicentric chromosome assay, which is based on the curcumin and trans-resveratrol pre-incubated human peripheral blood irradiation with ionizing radiation, samples culture and cytogenetic analysis of chromosomal aberrations. Analysis was based in dicentric chromosomes wich are considered biomarders of radiation-induced damage. On the other hand, the premature chromosome condensation technique, which is based on the curcumin and trans-resveratrol pre-incubated lymphocytes isolated from human peripheral blood, fusion with mitotic hamster ovary cells, culture and cytogenetic analysis. Analysis was focused in the counting of chromosomal fragments radio-induced. For the radiosensitivity studies, the G2-assay was applied in two different experiments. On the one hand, study of the radiosensitivity induced by curcumin and trans-resveratrol, aimed at evaluating the in vitro radiosensitivization ability of both compounds by modifying the lymphoyctes radiosensitivity in G2-cell cycle phase. On the other hand, the G2-assay was implemented in a case report in order to evaluate the individual radiosensibility in a patient undergoing interventionist radiology who suffered adverse secondary effects. With this assay, the patient can be classified as “hiperradiosensitive”, “radiosensitive”, “normal” or “radioresistant” according to the classification of Terzoudi and Pantelias (2011). Possible alterations in the chromosomal material caused by different chemical and physical agents can be evaluated by using cytogenetic biomarkers. The analysis of biomarkers for the assessment of the genotoxicity of tobacco and some components used in textile airbrushing with non adequate preventive measures ("Ardystil Syndrome") allowed to observe a statistically significant genetic affectation increase in smokers and check whether this affectation was no longer present in subjects affected by "Ardystil syndrome" after ten years of the outbreak. The in vitro study of the genotoxic, radiosensitizing and radioprotective properties of polyphenolic compounds, curcumin and trans-resveratrol, demonstrates the versatility of these compounds depending on the concentrations used, the cell cycle phase in which they are absorbed by cells and the conditions to which samples are subjected. The application of the individual radiosensitivity G2-assya in a patient with secondary effects after a medical intervention with ionizing radiation constitutes a first step for the future application of this cytogenetic technique in preventive medicine. Patients and workers subjected to ionizing radiation treatment would have an additional tool to improve the individualization of treatments as well as improving the prevention of occupational hazards

Microbiología alimentaria y fenómenos "paranormales" en la historia

Throughout history there have been seemingly inexplicable phenomena whose results have caused deaths, miracles, witchcraft trials and even profit and loss of military battles. This article presents a microbiological-historical survey where some microorganisms (Claviceps purpurea, Fusarium sporotrichioides, Stachybotrys chartarum and Serratia marcescens), may be the hypothetical cause of some of these phenomena.A lo largo de la historia han existido fenómenos aparentemente inexplicables cuyos resultados han originado muertes, milagros, juicios por brujería e incluso ganancias y pérdidas de batallas militares. En este artículo se realiza una inspección microbiológica-histórica en donde algunos microorganismos (Claviceps purpurea, Fusarium sporotrichioides, Serratia marcescens y Stachybotrys chartarum), pueden ser los hipotéticos causantes de algunos de estos fenómenos

Dose assessment intercomparisons within the RENEB network using G0-lymphocyte prematurely condensed chromosomes (PCC assay)

Purpose: Dose assessment intercomparisons within the RENEB network were performed for triage biodosimetry analyzing G0-lymphocyte PCC for harmonization, standardization and optimization of the PCC assay. Materials and methods: Comparative analysis among different partners for dose assessment included shipment of PCC-slides and captured images to construct dose-response curves for up to 6 Gy c-rays. Accident simulation exercises were performed to assess the suitability of the PCC assay by detecting speed of analysis and minimum number of cells required for categorization of potentially exposed individuals. Results: Calibration data based on Giemsa-stained fragments in excess of 46 PCC were obtained by different partners using galleries of PCC images for each dose-point. Mean values derived from all scores yielded a linear dose-response with approximately 4 excess-fragments/cell/Gy. To unify scoring criteria, exercises were carried out using coded PCC-slides and/or coded irradiated blood samples. Analysis of samples received 24 h post-exposure was successfully performed using Giemsa staining (1 excess-fragment/cell/Gy) or centromere/telomere FISH-staining for dicentrics. Conclusions: Dose assessments by RENEB partners using appropriate calibration curves were mostly in good agreement. The PCC assay is quick and reliable for whole- or partial-body triage biodosimetry by scoring excess-fragments or dicentrics in G0-lymphocytes. Particularly, analysis of Giemsa-stained excess PCC-fragments is simple, inexpensive and its automation could increase throughput and scoring objectivity of the PCC assay

Estudio transversal de medición de la composición corporal en pacientes con cáncer mediante antropometría y técnicas de imagen médica

Introduction: The main purpose of this study was to diagnose body composition in cancer patients before starting radiotherapy treatment, by using classic techniques based on anthropometry and biochemical parameters, as well as including new techniques based on computed tomography (TC) images.Material and methods: A sample of 22 patients with cancers that affect the digestive system underwent radiotherapy computed simulation which included measurements at L3 regions. Body composition was determined by using classic anthropometry, biochemical parameters and skeletal muscle mass by using Hounsfield Units (HU).Results: Mean BMI was 65,19 (±12,72) Kg, mean BMI 23,74 (± 5,03) kg/m2, mean average of WL 15,84 (±10,87) %, mean triceps skinfolds 9,73 (± 5,08) mm and mean brachial muscle perimeter 22,81 (± 2,95) cm. In terms of lab analysis, hipoalbumin was present in 63.45% of patients. On the other hand, according to body composition measured by CT scan, patients presented a mean waist circumference 99,06 (±13,38) cm, mean MM 119,41 (±35,54) cm2, and mean SMI 71,50 (±20.57) cm2/m2; being under normal cut points in 13,64% of patients.Conclusion: New techniques based on CT scans could be daily incorporated into clinical practice in cancer patients as an additional information of classic anthropometry and biochemical parameters, being a simple technique to perform, with low cost, reproducible and very reliable in terms of determination of body composition.Introducción: Analizar la composición corporal tanto mediante técnicas antropométricas y parámetros bioquímicos clásicos, como mediante técnicas modernas utilizando tomografía computarizada (TC), en pacientes oncológicos antes de iniciar el tratamiento con radioterapia.Metodología: Se analizaron de forma retrospectiva 22 pacientes con diversos tumores del aparato digestivo, que fueron sometidos al TC de planificación antes de iniciar el tratamiento con radioterapia, y que disponían de un corte axial en la tercera vértebra lumbar. Para analizar la composición corporal, se determinaron tanto parámetros antropométricos y bioquímicos clásicos, como la determinación de la masa muscular mediante Unidades Hounsfield (UH).Resultados: En cuanto a las características antropométricas clásicas, el peso medio fue 65,19 (±12,72) Kg, IMC 23,74 (± 5,03) kg/m2, %pp 15,84 (±10,87) %, PT 9,73 (± 5,08) mm y CMB 22,81 (± 2,95) cm. En cuanto a los parámetros bioquímicos, la hipoalbuminemia estuvo presente en el 63,45% de los casos. Por otro lado, la medición de composición corporal mediante técnicas modernas, determinó un promedio de circunferencia de cintura de 99,06 (±13,38) cm, MM de 119,41 (±35,54) cm2, y la media del IME fue de 71,50 (±20.57) cm2/m2; estando por debajo de la normalidad en el 13,64% de los pacientes.Conclusiones: Las nuevas técnicas por imagen basadas en cortes TC, pueden incluirse en la rutina diaria del paciente oncológico como información adicional a los parámetros antropométricos y bioquímicos más clásicos, por ser una técnica sencilla de realizar, con bajo coste, reproducible y muy fiable en cuanto a determinación de composición corporal

RENEB accident simulation exercise

Purpose: The RENEB accident exercise was carried out in order to train the RENEB participants in coordinating and managing potentially large data sets that would be generated in case of a major radiological event. Materials and methods: Each participant was offered the possibility to activate the network by sending an alerting email about a simulated radiation emergency. The same participant had to collect, compile and report capacity, triage categorization and exposure scenario results obtained from all other participants. The exercise was performed over 27 weeks and involved the network consisting of 28 institutes: 21 RENEB members, four candidates and three non-RENEB partners. Results: The duration of a single exercise never exceeded 10 days, while the response from the assisting laboratories never came later than within half a day. During each week of the exercise, around 4500 samples were reported by all service laboratories (SL) to be examined and 54 scenarios were coherently estimated by all laboratories (the standard deviation from the mean of all SL answers for a given scenario category and a set of data was not larger than 3 patient codes). Conclusions: Each participant received training in both the role of a reference laboratory (activating the network) and of a service laboratory (responding to an activation request). The procedures in the case of radiological event were successfully established and tested

RENEB intercomparisons applying the conventional Dicentric Chromosome Assay (DCA)

Purpose: Two quality controlled inter-laboratory exercises were organized within the EU project ‘Realizing the European Network of Biodosimetry (RENEB)’ to further optimize the dicentric chromosome assay (DCA) and to identify needs for training and harmonization activities within the RENEB network. Materials and methods: The general study design included blood shipment, sample processing, analysis of chromosome aberrations and radiation dose assessment. After manual scoring of dicentric chromosomes in different cell numbers dose estimations and corresponding 95% confidence intervals were submitted by the participants. Results: The shipment of blood samples to the partners in the European Community (EU) were performed successfully. Outside the EU unacceptable delays occurred. The results of the dose estimation demonstrate a very successful classification of the blood samples in medically relevant groups. In comparison to the 1st exercise the 2nd intercomparison showed an improvement in the accuracy of dose estimations especially for the high dose point. Conclusions: In case of a large-scale radiological incident, the pooling of ressources by networks can enhance the rapid classification of individuals in medically relevant treatment groups based on the DCA. The performance of the RENEB network as a whole has clearly benefited from harmonization processes and specific training activities for the network partners

Integration of new biological and physical retrospective dosimetry methods into EU emergency response plans : joint RENEB and EURADOS inter-laboratory comparisons

Purpose: RENEB, 'Realising the European Network of Biodosimetry and Physical Retrospective Dosimetry,' is a network for research and emergency response mutual assistance in biodosimetry within the EU. Within this extremely active network, a number of new dosimetry methods have recently been proposed or developed. There is a requirement to test and/or validate these candidate techniques and inter-comparison exercises are a well-established method for such validation. Materials and methods: The authors present details of inter-comparisons of four such new methods: dicentric chromosome analysis including telomere and centromere staining; the gene expression assay carried out in whole blood; Raman spectroscopy on blood lymphocytes, and detection of radiation induced thermoluminescent signals in glass screens taken from mobile phones. Results: In general the results show good agreement between the laboratories and methods within the expected levels of uncertainty, and thus demonstrate that there is a lot of potential for each of the candidate techniques. Conclusions: Further work is required before the new methods can be included within the suite of reliable dosimetry methods for use by RENEB partners and others in routine and emergency response scenarios

Investigation of the influence of calibration practices on cytogenetic laboratory performance for dose estimation

Purpose: In the frame of the QA program of RENEB, an inter-laboratory comparison (ILC) of calibration sources used in biological dosimetry was achieved to investigate the influence of calibration practices and protocols on the results of the dose estimation performance as a first step to harmonization and standardization of dosimetry and irradiation practices in the European biological dosimetry network. Materials and methods: Delivered doses by irradiation facilities used by RENEB partners were determined with EPR/alanine dosimetry system. Dosimeters were irradiated in the same conditions as blood samples. A short survey was also performed to collect the information needed for the data analysis and evaluate the diversity of practices. Results: For most of partners the deviation of delivered dose from the targeted dose remains below 10%. Deviations larger than 10% were observed for five facilities out of 21. Origins of the largest discrepancies were identified. Correction actions were evaluated as satisfactory. The re-evaluation of some ILC results for the fluorescence in situ hybridization (FISH) and premature chromosome condensation (PCC) assays has been performed leading to an improvement of the overall performances. Conclusions: This work has shown the importance of dosimetry in radiobiology studies and the needs of harmonization, standardization in irradiation and dosimetry practices and educational training for biologists using ionizing radiation

Strawberry (Fragaria x ananassa) and Kiwifruit (Actinidia deliciosa) Extracts as Potential Radioprotective Agents: Relation to Their Phytochemical Composition and Antioxidant Capacity

[EN] Ionising radiation is an important form of treatment for human cancer; however, the side effects associated with oxidative damage caused by radiation compromise its effectiveness. This work aimed to quantify the major bioactive components of freeze-dried kiwifruit (KD) and strawberry (SD) extracts and assess their potential efficacy as radioprotective agents in human blood lymphocytes. Their possible genotoxic and cytotoxic effects were also evaluated. The study was conducted by pre-treating human lymphocytes with KD and SD (50, 400, and 800 ¿g/mL) before radiation at 2 Gy. The results showed that SD presented a higher antioxidant capacity (12.6 mmol Trolox equivalents/100 g db) and higher values of total phenolic compounds (2435 mg of gallic acid equivalents/100 g db), while KD had the highest vitamin C content (322 mg ascorbic acid/100 g db). Regarding phenolic compounds, pelargonidin-3-glucoside was the most abundant in SD (1439 mg/1000 g db) and quercetin-3-O-galactoside in KD (635 mg/1000 g db). None of the tested concentrations of both fruit extracts showed a genotoxic effect. SD (800 ¿g/mL) reduced the sister chromatid exchange frequency and mitotic index. The efficacy of KD (400 and 800 ¿g/mL) in lowering the dicentric chromosome frequency demonstrated its radioprotective activity.This research was funded by Vicerrectorado de Investigacion, Universitat Politecnica de Valencia (UPV-FE-2013-56) (Spain).Ribeiro, MDS.; Sebastià, N.; Montoro, A.; García Martínez, EM. (2023). Strawberry (Fragaria x ananassa) and Kiwifruit (Actinidia deliciosa) Extracts as Potential Radioprotective Agents: Relation to Their Phytochemical Composition and Antioxidant Capacity. Applied Sciences. 13(15). https://doi.org/10.3390/app13158996131

Microbiología alimentaria y fenómenos "paranormales" en la historia

Throughout history there have been seemingly inexplicable phenomena whose results have caused deaths, miracles, witchcraft trials and even profit and loss of military battles. This article presents a microbiological-historical survey where some microorganisms (Claviceps purpurea, Fusarium sporotrichioides, Stachybotrys chartarum and Serratia marcescens), may be the hypothetical cause of some of these phenomena.A lo largo de la historia han existido fenómenos aparentemente inexplicables cuyos resultados han originado muertes, milagros, juicios por brujería e incluso ganancias y pérdidas de batallas militares. En este artículo se realiza una inspección microbiológica-histórica en donde algunos microorganismos (Claviceps purpurea, Fusarium sporotrichioides, Serratia marcescens y Stachybotrys chartarum), pueden ser los hipotéticos causantes de algunos de estos fenómenos