112 research outputs found

    Exploratory Evaluation of Retranslocation and Bioconcentration of Heavy Metals in Three Species of Mangrove at Las Cucharillas Marsh, Puerto Rico

    Get PDF
    Heavy metal contamination in the coastal area of Cataño, Puerto Rico accountable to anthropogenic sources is of great concern due to the risk posed over the surrounding communities and adjacent ecosystems. Estuarine ecosystems are widely recognized for the presence of mangroves. This type of flora is recognized for their many beneficial properties for example, the ability to purge aquatic ecosystems where they stand. Exploratory analyses on the phytoaccumulative capacity of three mangrove species for ten metals (Hg, Al, As, Cd, Cr, Cu, Fe, Pb, Mg, Zn) were performed in this research. Random soil samples and both green and senescent leaves of Rhizophora mangle, Laguncularia racemosa and Avicennia germinans from three different sites of Peninsula La Esperanza were analyzed in order to apply the retranslocation efficiency (RT%) and bioconcentration factor (BCF) concepts. After calculating the RT% and the BCF, comparison analyses among the three mangrove species were performed. In general, the results showed low RT% values for Avicennia in comparison with Rhizophora and Laguncularia. BCF values confirmed RT% results for Avicennia, showing higher heavy metal concentrations in its senescent leaves in contrast with the other species. Therefore, these preliminary results suggest that Rhizophora and Laguncularia act better as phytoremediators for heavy metals in polluted areas due to their ability to accumulate lower concentrations in senescent leaves; preventing further contamination in surrounding ecosystems by encapsulating the pollutants instead of exporting them

    Food Characterization of the Spotted Pimelodid Fish Pimelodus Maculatus From a Polluted Urban River in Argentina

    Full text link
    On the present study, the nourishment and the digestive system of a population of the spotted pimelodid Pimelodus maculatus LacepĂšde 1803 from a polluted urban river in Argentina were analyzed (Reconquista River, Buenos Aires province). The specimens are characterized by having benthic habits and an omnivore diet. In their intestinal content, a diversity of components was identified. Such components were grouped into ten alimentary items, with dietary variations according to body size while the longitude of the intestine remained proportional to standard length. Microbiological analysis in the gills, stomach and intestine showed the occurrence of Staphylococcus aureus, Escherichia coli and Salmonella sp. Fungi and yeast were also detected. Bacterial accounts were very high both in the analyzed organs as well in water samples. The ecological and sanitary significance of the identified bacteria is discussed

    Down-regulation of the Lamin A/C in neuroblastoma triggers the expansion of tumor initiating cells

    Get PDF
    Tumor-initiating cells constitute a population within a tumor mass that shares properties with normal stem cells and is considered responsible for therapy failure in many cancers. We have previously demonstrated that knockdown of the nuclear envelope component Lamin A/C in human neuroblastoma cells inhibits retinoic acid-mediated differentiation and results in a more aggressive phenotype. In addition, Lamin A/C is often lost in advanced tumors and changes in the nuclear envelope composition occur during tumor progression. Based on our previous data and considering that Lamin A/C is expressed in differentiated tissues, we hypothesize that the lack of Lamin A/C could predispose cells toward a stem-like phenotype, thus influencing the development of tumor-initiating cells in neuroblastoma. This paper demonstrates that knockdown of Lamin A/C triggers the development of a tumor-initiating cell population with self-renewing features in human neuroblastoma cells. We also demonstrates that the development of TICs is due to an increased expression of MYCN gene and that in neuroblastoma exists an inverse relationship between LMNA and MYCN expression

    Sistema de Recomendação AcadĂȘmico para Apoio a Aprendizagem

    Get PDF
    Os sistemas de recomendação surgiram com o objetivo de auxiliar os usuĂĄrios no processo de busca na Web, indicando informaçÔes para o usuĂĄrio com base no seu perfil. Esses sistemas sĂŁo de grande valia para o processo de aprendizagem, pois professores e alunos podem realizar buscas por conteĂșdos educacionais mais apropriados ao seu perfil (nĂ­vel de formação, ĂĄreas de interesse, etc.). Este artigo apresenta um modelo de referĂȘncia para sistema de recomendação, que dispensa a intervenção do usuĂĄrio no momento de traçar seu perfil e utiliza tĂ©cnicas de mineração de dados. O modelo foi implementado no protĂłtipo “Ponto com Filtro” para verificar sua aplicabilidade

    ANÁLISE SOCIAL E ERGONÔMICA DA ATIVIDADE DE COLETA INFORMAL DE MATERIAL RECICLÁVEL

    Get PDF
    A atividade de coletar materiais reciclĂĄveis das ruas tem aumentado consideravelmente no Brasil. Por ser uma profissĂŁo exercida nas vias urbanas, acaba absorvendo aspectos negativos que inevitavelmente acabam por prejudicar o trabalhador. AlĂ©m de problemas relacionados Ă  saĂșde no trabalho, Ă© visĂ­vel um processo de exclusĂŁo dessas pessoas por uma maioria da população. Com isso, o presente artigo tem como objetivo analisar a situação atual desta atividade, apontando suas carĂȘncias e reais necessidades, a fim de tornĂĄ-la mais humana. Como ferramentas de pesquisa, foram feitas entrevistas e anĂĄlises observatĂłrias em diversos locais, constatando-se que estes trabalhadores sĂŁo prejudicados por problemas nĂŁo sĂł ergonĂŽmicos, mas tambĂ©m sociais, e por isso sugere-se uma abordagem a fim de criar um vĂ­nculo entre o catador e a sociedade que o rodeia, para que entĂŁo se possa tambĂ©m resolver as questĂ”es ergonĂŽmicas, que acabam sendo secundĂĄrias quando os trabalhadores sĂŁo incluĂ­dos em uma sociedade que os exclui.Palavras-chave: Catadores de materiais reciclĂĄveis. Ergonomia. Sociedade. Reciclagem. Design social.ABSTRACTThe activity of collecting recyclable materials from the streets has increased considerably in Brazil. Being a profession exercised on the streets it ends up absorbing negatives aspects that inevitably end up harming the worker. In addition to the problems related to work health, a process of exclusion of these people by a majority of the population is visible. Therefore, this article aims to analyze the current situation of this the activity, pointing out its real needs, in order to make it more human. As research tools, interviews and observatory analysis were made in several places, showing that these workers are not only harmed by ergonomic problems but also by social issues, and because of that a different approach is suggested, aiming the development of a bond between the worker and the society around him so the ergonomic issues can be solved, since they end up being secondary when the workers are included in a society that excludes them.Keywords: Recyclable material collectors. Ergonomics. Society. Recycling. Social design

    Circulation of respiratory viruses during the COVID-19 pandemic in The Gambia

    Get PDF
    Background: In many countries, non-pharmaceutical interventions to limit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission resulted in significant reductions in other respiratory viruses. However, similar data from Africa are limited. We explored the extent to which viruses such as influenza and rhinovirus co-circulated with SARS-CoV-2 in The Gambia during the COVID-19 pandemic.  Methods: Between April 2020 and March 2022, respiratory viruses were detected using RT-PCR in nasopharyngeal swabs from 1397 participants with influenza-like illness. An assay to detect SARS-CoV-2 and a viral multiplex RT-PCR assay was used as previously described  to detect influenza A and B, respiratory syncytial virus (RSV) A and B, parainfluenza viruses 1-4, human metapneumovirus (HMPV), adenovirus, seasonal coronaviruses (229E, OC43, NL63) and human rhinovirus. Results: Overall virus positivity was 44.2%, with prevalence higher in children 50 years (39.9%), p50 years (24.3%), p50 years (6.3%), p<0.0001. Four SARS-CoV-2 waves occurred, with 36.1%-52.4% SARS-CoV-2 positivity during peak months. Influenza infections were observed in both 2020 and 2021 during the rainy season as expected (peak positivity 16.4%-23.5%). Peaks of rhinovirus were asynchronous to the months when SARS-CoV-2 and influenza peaked. Conclusion: Our data show that many respiratory viruses continued to circulate during the COVID-19 pandemic in The Gambia, including human rhinoviruses, despite the presence of NPIs during the early stages of the pandemic, and influenza peaks during expected months

    Management of anaphylaxis due to COVID-19 vaccines in the elderly

    Get PDF
    Older adults, especially men and/or those with diabetes, hypertension, and/or obesity, are prone to severe COVID-19. In some countries, older adults, particularly those residing in nursing homes, have been prioritized to receive COVID-19 vaccines due to high risk of death. In very rare instances, the COVID-19 vaccines can induce anaphylaxis, and the management of anaphylaxis in older people should be considered carefully. An ARIA-EAACI-EuGMS (Allergic Rhinitis and its Impact on Asthma, European Academy of Allergy and Clinical Immunology, and European Geriatric Medicine Society) Working Group has proposed some recommendations for older adults receiving the COVID-19 vaccines. Anaphylaxis to COVID-19 vaccines is extremely rare (from 1 per 100,000 to 5 per million injections). Symptoms are similar in younger and older adults but they tend to be more severe in the older patients. Adrenaline is the mainstay treatment and should be readily available. A flowchart is proposed to manage anaphylaxis in the older patients.Peer reviewe

    ARIA‐EAACI care pathways for allergen immunotherapy in respiratory allergy

    Get PDF

    Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

    Get PDF
    Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe
    • 

    corecore