168 research outputs found
Cyanobacteria of the thermal spring at Pancharevo, Sofia, Bulgaria
Eight taxa of cyanobacteria were identified in the thermal spring at Pancharevo (in the Sofia basin, Bulgaria). As well as the widespread Lyngbya thermalis, Phormidesmis molle (syn. Phormidium molle), Phormidium papyraceum, Phormidium corium and Mastigocladus laminosus, four species were identified for the first time in Bulgaria: Calothrix thermalis, Gloeocapsa gelatinosa, Leibleinia epiphytica and Symploca thermalis
Application of an universal DNA microarray to cyanobacterial diversity assessment
peer reviewedOur technological goal was to test the new technology of DNA microarrays in the field of biodiversity assessments. The efficiency of DNA microarrays; was compared against the "classical" methods for measuring and monitoring the biodiversity. We use cyanobacteria from freshwater lakes as model organisms belonging to a well defined phylum of much ecological relevance. The combination of the information about cyanobacterial biodiversity together with the data describing the water quality of the lakes may reveal useful information to design management actions to control the unwanted mass developments of cyanobacteria. Such blooms prevent the use of water for drinking and for recreation and can be toxic to animals and humans. The possibility to automate the microarray technology in water quality monitoring will be an interesting alternative to time-consuming microscopic enumerations.MIDI-CHI
White Paper: Addressing the challenges of global warming for polar freshwater resources
The polar regions are undergoing rapid transformations
due to global warming, resulting in temperature increases far surpassing the global average and significantly impacting ecosystems, especially freshwater systems. Understanding the implications of climate change on Arctic
and Antarctic freshwater systems is crucial, as vital ecosystem services essential for sustaining human and environmental well-being may be disrupted. Shifts in freshwater availability due to changes in precipitation patterns, ice melt, and permafrost thaw pose significant challenges for local communities, exacerbating their vulnerabilities. Additionally, climate warming can affect water quality, e. g. by releasing pollutants and potential hazardous microorganisms, further jeopardizing human and natural ecosystem health. Arctic communities face multiple challenges in adapting to these changes, including limited resources and infrastructure that may not be resilient to environmental change. Urgent action is needed to mitigate these impacts and safeguard freshwater resources through evidence-based approaches, scientific research, policy involvement, and community engagement to ensure a sustainable future in the polar regions. In the pursuit of understanding freshwater dynamics in the Arctic and Antarctic, international collaboration across disciplines stands as a cornerstone, essential for addressing
the impacts of climate change on polar freshwater resources. Initiatives aiming to understand the dynamics of transboundary water resources underscore the pivotal role of
collaboration across institutions and nations, allowing for
collective efforts in providing effective solutions to advance the current knowledge of polar ecosystems. Such collaboration not only benefits the polar regions but also carries implications for the global community, aligning with the UN’s SDGs. Therefore, funding mechanisms to bridge the knowledge-to-action gap and support international cooperation should be set high in the research agenda.
The scientific and funding roadmap presented here should
be implemented urgently, to maximise, in a 10-year term,
the benefits to be gained through synergies with the next
International Polar Year (2032-33). It will leverage existing transnational initiatives and frameworks, including the Antarctic governance framework, to guide future research initiatives towards sustainable management of freshwater
resources. Overall, a comprehensive approach integrating
pole-to-pole collaboration, strategic funding, and adherence to governance frameworks is paramount, ensuring collective efforts contribute to the well-being of polar communities and the broader global understanding of climate change implications
Bacterial Community Profiling of Milk Samples as a Means to Understand Culture-Negative Bovine Clinical Mastitis
Inflammation and infection of bovine mammary glands, commonly known as mastitis, imposes significant losses each year in the dairy industry worldwide. While several different bacterial species have been identified as causative agents of mastitis, many clinical mastitis cases remain culture negative, even after enrichment for bacterial growth. To understand the basis for this increasingly common phenomenon, the composition of bacterial communities from milk samples was analyzed using culture independent pyrosequencing of amplicons of 16S ribosomal RNA genes (16S rDNA). Comparisons were made of the microbial community composition of culture negative milk samples from mastitic quarters with that of non-mastitic quarters from the same animals. Genomic DNA from culture-negative clinical and healthy quarter sample pairs was isolated, and amplicon libraries were prepared using indexed primers specific to the V1–V2 region of bacterial 16S rRNA genes and sequenced using the Roche 454 GS FLX with titanium chemistry. Evaluation of the taxonomic composition of these samples revealed significant differences in the microbiota in milk from mastitic and healthy quarters. Statistical analysis identified seven bacterial genera that may be mainly responsible for the observed microbial community differences between mastitic and healthy quarters. Collectively, these results provide evidence that cases of culture negative mastitis can be associated with bacterial species that may be present below culture detection thresholds used here. The application of culture-independent bacterial community profiling represents a powerful approach to understand long-standing questions in animal health and disease
Threat management priorities for conserving Antarctic biodiversity
Antarctic terrestrial biodiversity faces multiple threats, from invasive species to climate change. Yet no large-scale assessments of threat management strategies exist. Applying a structured participatory approach, we demonstrate that existing conservation efforts are insufficient in a changing world, estimating that 65% (at best 37%, at worst 97%) of native terrestrial taxa and land-associated seabirds are likely to decline by 2100 under current trajectories. Emperor penguins are identified as the most vulnerable taxon, followed by other seabirds and dry soil nematodes. We find that implementing 10 key threat management strategies in parallel, at an estimated present-day equivalent annual cost of US$23 million, could benefit up to 84% of Antarctic taxa. Climate change is identified as the most pervasive threat to Antarctic biodiversity and influencing global policy to effectively limit climate change is the most beneficial conservation strategy. However, minimising impacts of human activities and improved planning and management of new infrastructure projects are cost-effective and will help to minimise regional threats. Simultaneous global and regional efforts are critical to secure Antarctic biodiversity for future generations
TerrANTALife 1.0 Biodiversity data checklist of known Antarctic terrestrial and freshwater life forms
Incomplete species inventories for Antarctica represent a key challenge for comprehensive ecological research and conservation in the region. Additionally, data required to understand population dynamics, rates of evolution, spatial ranges, functional traits, physiological tolerances and species interactions, all of which are fundamental to disentangle the different functional elements of Antarctic biodiversity, are mostly missing. However, much of the fauna, flora and microbiota in the emerged ice-free land of the continent have an uncertain presence and/or unresolved status, with entire biodiversity compendia of prokaryotic groups (e.g. bacteria) being missing. All the available biodiversity information requires consolidation, cross-validation, re-assessment and steady systematic inclusion in order to create a robust catalogue of biodiversity for the continent
Comparison of placenta samples with contamination controls does not provide evidence for a distinct placenta microbiota
TP53 polymorphism, HPV infection, and risk of cervical cancer.
The role of a polymorphism at position 72 of the tumor suppressor gene TP53 in the development of cervical cancer is not well established. The arginine variant of the p53 protein could be more susceptible to degradation by human papillomavirus (HPV) E6 protein than the protein containing proline. Recent studies show controversial results. We investigated a possible association between TP53 polymorphism and cervical cancer in a Peruvian population with high prevalence of HPV infection. HPV status and TP53 polymorphism were determined for 119 cases of invasive cervical cancer and 127 control women from Peru. HPV infection was detected by PCR of cervical cells or tumor biopsies. For determination of TP53 polymorphism, exon 4 of the TP53 gene was amplified by PCR, and DNA was subsequently subjected to restriction enzyme digest. Associations between TP53 polymorphism, HPV infection, and cervical cancer were assessed using logistic regression. Women homozygotes for arginine had a 2.2-fold increased risk (95% confidence interval: 0.6-7.6) for cervical cancer. The odds ratio for women heterozygotes for Arg/Pro was 3.5 (95% confidence interval: 0.9-14). Similarly increased risks were found when restricting analysis to HPV-positive women only. The distribution of TP53 genotypes in this Peruvian population was comparable with that found in Caucasians. Our results cannot rule out an association between the TP53 polymorphism at codon 72, HPV infection, and the etiology of cervical cancer
SOP 4.1. Taxonomic identification by light microscopy
A rapid taxonomic identification is important for estimating potential risks to animal and human health caused by cyanobacteria in waters used for recreation, drinking and irrigation. Light microscopy provides a rapid means for preliminary identification and quantitative estimation of potentially toxic cyanobacteria based on their morphology (morphotypes). However, the final species assignment should rely on a polyphasic characterization of cultured strains (or population isolates) consisting of several different molecular methods, and (whenever possible) the determination of ultrastructural, physiological, biochemical, and ecological characteristics. In this chapter, we describe the major steps essential for cyanobacterial taxa identification. These include examination by light microscopy, genetic characterization by single or multiple loci sequence analyses, and by molecular typing. The value of taxonomic and molecular databases is explained. Finally, the usefulness of a polyphasic approach is highlighted by examples. Although analyses of genes known to be involved in toxin synthesis can be helpful for the identification of potentially toxic strains (or population isolates), reliable health risk assessments require confirmation by analytical measurement of the respective cyanotoxins
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