Zebrafish and Nuclear Medicine methods and techniques: an each-day improving partnership

Aims: This work aims the introduction of zebrafish as a very promising and each day more interesting animal model in radiobiology. It will be briefly discussed the most relevant advantages and disadvantages related with the use of zebrafish, mentioning some of the previous studies using this model in Nuclear Medicine and concluding with its potential applications

Evaluation of Radiobiological Effects in Three Distinct Biological Models

The present work aims to share the process of development of advanced biological models to study radiobiological effects. Recognizing several known limitations and difficulties of the current monolayer cellular models, as well as the increasing difficulties to use advanced biological models, our group has been developing advanced biological alternative models, namely three- dimensional cell cultures and a less explored animal model (the Zebrafish - Danio rerio - which allows the access to inter-generational data, while characterized by a great genetic homology towards the humans). These three models (monolayer cellular model, three-dimensional cell cultures and zebrafish) were externally irradiated with 100mGy, 500mGy or 1Gy. The consequences of that irradiation were studied using cellular and molecular tests

Modern Radiobiology: Study of Ionizing Radiation Biological Effects using ThreeDimensional Cell Cultures

Biological effects of high doses of ionizing radiation are reasonably well studied and documented. Nevertheless, there is a clear lack of information and/or evidence concerning biological effects of Low Doses, namely at medical imaging levels, as those characterizing Nuclear Medicine and Radiology typical environments. Our group has being involved in the in vitro study of these low dose radiobiological effects. Preliminary experimental results with 100mGy external gamma irradiation of HepG2 monolayer cells showed a slight increase in the proliferation rate 24h, 48h and 72h post irradiation. These preliminary results also pointed into the presence of some Bystander effects 72h post irradiation, constituting the starting point and motivation for the need of a more accurate analysis , here presented

Assessing Radiobiological Effects of Low Doses of Ionizing Radiation on Zebrafish by Bidimensional Gel Electrophoresis

Aim: This paper relates with a specific task from a larger research project oriented to the development and application of the Zebrafish – Danio rerio – to the study of radiobiological effects of medical diagnostic level – low doses – of ionizing radiation

Allergies and Diabetes as Risk Factors for Dengue Hemorrhagic Fever: Results of a Case Control Study

Dengue is an arboviral disease that affects large areas of countries in tropical and subtropical regions of the world. Around 500,000 cases and 22,000 deaths of dengue hemorrhagic fever (DHF)/Dengue Shock Syndrome (DSS), the most severe presentations of this disease, occur annually. It is unclear why some cases of dengue fever (0.5% to 4%) progress to DHF/DSS. There is weak evidence that some diseases could have a role in this process, such as diabetes, hypertension, and allergies. In epidemics most dengue fever cases are sent home as there are too many to be kept in observation, but if it were possible to identify those with a higher risk of progression to DHF, they could be kept for observation, for early detection of signs, symptoms and alterations in laboratory tests suggestive of DHF, to enable timely and effective clinical management and early intervention. We study this issue and we believe that the evidence produced in this study, when confirmed in other studies, suggests that screening criteria might be used to identify adult patients at a greater risk of developing DHF with a recommendation that they remain under observation and monitoring in a hospital

Study of radiobiological effects of low doses of ionizing radiation using comet assay on zebrafish model

Present paper relates with the analysis of radiobiological effects, in a context of ionizing radiation low doses, using an advanced biological model, the zebrafish - Danio rerio - and comet assay based analytical methodology. The use of zebrafish has grown considerably in recent years, assuming more and more is role as a very promising model in biomedical research, both because of the high level of homology shared with the human genome, and an assumedly easy - and reasonably priced - practical side. To obtain the data here mentioned, it has been used a population of circa 300 animals, divided in four groups of 75 each, all having been externally irradiated with three distinct dose protocols: 100, 500 and 1.000 mGy. The postures of the irradiated fish were collected and groups of adult animals were killed in three different moments: 1, 4 and 7 days after the irradiation. DNA damage in adults and in larvae were studied using comet assay. The results related to damages were processed and presented in terms of percentual of DNA in tail, allowing an approximation to the relative number of DNA breaks induced by the radiation exposure

Developing advanced biological models to study effects of low doses of ionizing radiation: our experience.

The biological effects of high doses of ionizing radiation are reasonably well studied and documented. Nevertheless, there is a clear lack of evidence concerning biological effects of Low Doses, namely at medical imaging levels, as those characterizing Nuclear Medicine and Radiology typical environments. Recognizing limitations and translational difficulties of the actual monolayer cellular models, our group has produced efforts to develop advanced biological models, namely using three-dimensional cell cultures and a less explored animal model (Zebrafish - which allow access to inter-generational data, while characterized by a great genetic homology). This work aims to exhibit preliminary results already obtaine

Structure of Hierridin C, Synthesis of Hierridins B and C, and Evidence for Prevalent Alkylresorcinol Biosynthesis in Picocyanobacteria

Small, single-celled planktonic cyanobacteria are ubiquitous in the world's oceans yet tend not to be perceived as secondary metabolite-rich organisms. Here we report the isolation and structure elucidation of hierridin C, a minor metabolite obtained from the cultured picocyanobacterium Cyanobium sp. LEGE 06113. We describe a simple, straightforward synthetic route to the scarcely produced hierridins that relies on a key regioselective halogenation step. In addition, we show that these compounds originate from a type III PKS pathway and that similar biosynthetic gene clusters are found in a variety of bacterial genomes, most notably those of the globally distributed picocyanobacteria genera Prochlorococcus, Cyanobium and Synechococcus.info:eu-repo/semantics/publishedVersio

Air Travel Is Associated with Intracontinental Spread of Dengue Virus Serotypes 1–3 in Brazil

Dengue virus and its four serotypes (DENV-1 to DENV-4) infect 390 million people and are implicated in at least 25,000 deaths annually, with the largest disease burden in tropical and subtropical regions. We investigated the spatial dynamics of DENV-1, DENV-2 and DENV-3 in Brazil by applying a statistical framework to complete genome sequences. For all three serotypes, we estimated that the introduction of new lineages occurred within 7 to 10-year intervals. New lineages were most likely to be imported from the Caribbean region to the North and Northeast regions of Brazil, and then to disperse at a rate of approximately 0.5 km/day. Joint statistical analysis of evolutionary, epidemiological and ecological data indicates that aerial transportation of humans and/or vector mosquitoes, rather than Aedes aegypti infestation rates or geographical distances, determine dengue virus spread in Brazil

Serologic Survey of Hantavirus Infection, Brazilian Amazon

Federal University of Maranhão. São Luís, MA, Brazil.Federal University of Maranhão. São Luís, MA, Brazil.Federal University of Maranhão. São Luís, MA, Brazil.Federal University of Maranhão. São Luís, MA, Brazil.Federal University of Maranhão. São Luís, MA, Brazil.Federal University of Maranhão. São Luís, MA, Brazil.State Department of Health. São Luís, MA, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Belém, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Belém, PA, Brasil