13 research outputs found

    Atopobium vaginae and Prevotella bivia are able to incorporate and influence gene expression in a pre-formed Gardnerella vaginalis biofilm

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    Bacterial vaginosis (BV) is associated with a highly structured polymicrobial biofilm on the vaginal epithelium where Gardnerella species presumably play a pivotal role. Gardnerella vaginalis, Atopobium vaginae, and Prevotella bivia are vaginal pathogens detected during the early stages of incident BV. Herein, we aimed to analyze the impact of A. vaginae and P. bivia on a pre-established G. vaginalis biofilm using a novel in vitro triple-species biofilm model. Total biofilm biomass was determined by the crystal violet method. We also discriminated the bacterial populations in the biofilm and in its planktonic fraction by using PNA FISH. We further analyzed the influence of A. vaginae and P. bivia on the expression of key virulence genes of G. vaginalis by quantitative PCR. In our tested conditions, A. vaginae and P. bivia were able to incorporate into pre-established G. vaginalis biofilms but did not induce an increase in total biofilm biomass, when compared with 48-h G. vaginalis biofilms. However, they were able to significantly influence the expression of HMPREF0424_0821, a gene suggested to be associated with biofilm maintenance in G. vaginalis. This study suggests that microbial relationships between co-infecting bacteria can deeply affect the G. vaginalis biofilm, a crucial marker of BV.This research was partially funded by the National Institute of Allergy and Infectious Diseases (R01AI146065-01A1). It was also partially funded by the Portuguese Foundation for Science and Technology (FCT), by the research project (PTDC/BIA-MIC/28271/2017), under the scope of COMPETE 2020 (POCI-01-0145-FEDER-028271), and by the strategic funding of unit (UIDB/04469/2020).info:eu-repo/semantics/publishedVersio

    How variations in concentrations of metal ions and suspended solids downstream river Rwabakazi in Uganda can be used to study pollution

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    Pollution is affecting river Rwabakazi in the Nile basin. Its effects are reflected by high turbidity, pH, total suspended solids, (T.S.S.), electrical conductivity, metal ions concentrations, and low concentration of dissolved oxygen (DO5). In this study, we report the variations in selected physicochemical parameters of waters of the Rwabakazi river.  Turbidity, pH, concentrations of selected metal ions, T.S.S., and DO5 of water sampled from three selected sites on the river in Kabale were very high. Mean DO5 fell from 96 ± 2 mg/L to 86± 1.5 mg/L downstream. The mean pH fell from 7.8 ± 0.03 to 7.6 ± 0.04, showing the removal of basic components. The turbidity dropped from370 ± 3 NTU to 305 ± 2 NTU, showing that the haziness of water decreased. The concentration of iron(II) fell from 320 ± 0.3 mg/L to 291 ± 0.2 mgL-1 indicating the fair extent of heavy metal ions downstream. The T.S.S. decreased from 330 ± 5 mg/L to 300± 5 mg/L, and concentrations of calcium and magnesium ions also decreased, providing evidence for self-purification. The available data suggests that river Rwabakazi is polluted as a result of poor agricultural practices, erosion, and flash flooding.  Further studies on nutrient and pesticide pollution of this river need to be carried out, and trees should be planted on steep open surfaces to minimize erosion.

    Ancient and historical systems

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    Plants and Their Microbes

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    The soil harbors billions of Microbes supporting the growth of several plants, resulting in the constant symbiotic or non-symbiotic interactions between the plants and these microorganisms known as plant-microbe interactions. Plants need nutrients (available or available but inaccessible) in the soil to grow while microbes need shelter and nutrients supplied by plants and also promote plant-growth. Microbes are constantly trading with plants either buying or selling nutrients (the nutrients are considered the main currencies for trading and the product being bought in the soil rhizosphere). Plants including legumes inoculated with Rhizobia and microbes in experimental studies show that they are able to solubilizing phosphate and metals, fixing nitrogen fixers, producing IAA, cytokinins, Gibberellins and Ethylene. Microbiomes are therefore essential for plant growth and health as they govern most soil functions affecting plant-growth. For higher crop-yields and increased soil- fertility using ecofriendly manner, researches focused on the new concepts of exotic biomolecules, hormones, enzymes and metabolites which create a suitable environment for the interaction between plant and microbes using molecular and biotechnological approaches are necessary to increase our knowledge of rhizosphere biology and to achieve an integrated management of soil microbial populations that can ultimately enhance the health of plants

    SEAFDEC Asian Aquaculture Volume 24(2) April - May 2002

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    Preliminary assessment of the interaction of introduced biological agents with biofilms in water distribution systems.

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    Highly efficient selection, enumeration, enrichment, and molecular profiling of low-abundance biological cells

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    After brief overviews of low-abundance cell selection techniques in chapter 1 and circulating tumor cells in chapter 2, this dissertation initially focuses on the development of aptamer incorporated high-throughput microfluidic techniques to select rare circulation prostate cancer cells (LNCaP) directly from whole blood with subsequent quantification of these rare cells using a non-labeling approach. Then, I extended the technology to environmental samples in an effort around time, sensitivity, and portability of traditional groundwater assessment. As a model bio- pathogen, E. coli O157:H7 was chosen due to its toxicity and its adverse impact on recreational waters. Low-abundance (\u3c100 cells mL-1) E. coli O157:H7 cells were isolated and enriched from environmental water samples using a microfluidic chip that its capture beds were covalently decorated with E.coli O157:H7 specific polyclonal antibodies. The selected cells were enumerated using RT-qPCR technique. Finally, I have integrated HTMSU with electrokinetic enrichment microfluidic unit for performance of single recombinant low-abundance CTC cell-based assay. A series of analytical processes were carried out, including immunoaffinity selection of rare CTCs, quantification of selected cells via conductivity impedance and electrophoretic enrichment of selected cells for PCR/LDR/CE interrogation for detection of low-abundance point mutations in genomic DNA

    Civil society mobilisation after Cyclone Tracy, Darwin 1974

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    Major disasters challenge or exceed the capacity of the official emergency management sector to provide needed rescue services, support and relief. Emergency services in most jurisdictions do not have the surge capacity for unusual or extreme events without drawing on other jurisdictions or local people from outside the formal emergency management organisations. In such circumstances, those in the affected area need to organise themselves and make maximum use of local resources to cope with the immediate aftermath of impact. To find the required surge capacity, this suggests a whole of society response with the official system working with the capacities of people, commerce and organisations outside the emergency sector. An example is provided by the destruction of the northern Australian capital city of Darwin by Cyclone Tracy in December 1974. Informal volunteering and emergent leadership in Darwin and across Australia were critical to the immediate response and relief. Volunteering was widespread and worked well alongside official emergency management. With today’s information and communication technologies and a strong national resilience narrative, we would expect to do at least as well. However, governments now exercise much more control over civil society. We examine the implications for surge capacity and adaptability

    Philosophical considerations in health: conceptualizing to educate—a perspective on neglected tropical diseases in Brazil

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    This paper aims to recover the history of health concept evolution from its birth in Ancient Greece to the contemporary days, drawing an overview of the firsts philosophical thoughts about health in distinctive historical periods, analyzing how this concept has been impacted by knowledge improvement and both research and technological discoveries over time. In order to understand the persistence of Neglected Tropical Diseases which causes physical disabilities and social discrimination, this paper will focus on Leprosy and Cutaneous Leishmaniasis and its relation to social inequality mainly in developing countries. These approaches on the understanding of the health-disease binomial are necessary to reflect on health in the course of human history and, from there, to promote joint actions both in the area of scientific research and health education
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