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1.
Support Care Cancer ; 29(4): 2073-2082, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32862355

RESUMO

BACKGROUND: Indigenous Australians diagnosed with cancer have substantially higher cancer mortality rates compared with non-Indigenous Australians, yet there is a paucity of information about their end-of-life service utilisation and supportive care needs. PURPOSE: To describe the service utilisation and supportive care needs of Aboriginal and Torres Strait Islander people with cancer at end-of-life. METHOD: Hospital admission data were linked to self-reported data from a study of Indigenous cancer patients from Queensland, Australia during the last year of their life. Needs were assessed by the Supportive Care Needs Assessment Tool for Indigenous Cancer Patients which measures 26 need items across 4 domains (physical/psychological; hospital care; information/communication; practical/cultural). A descriptive analysis of health service utilisation and unmet needs was conducted. RESULTS: In total, 58 Indigenous cancer patients were included in this analysis. All patients had at least one hospital admission within the last year of their life. Most hospital admissions occurred through emergency (38%) and outpatient (31%) departments and were for acute care (85%). Palliative care represented 14% of admissions and 78% died in hospital. Approximately half (48%) did not report any unmet needs. The most frequently reported moderate-to-high unmet need items were worry about the treatment results (17%), money worries (16%) and anxiety (16%). CONCLUSIONS: Utilisation of palliative care services that manage a full range of physical and psychosocial needs was low. Addressing worries about treatment results, finances and generalised anxiety are priorities in this population.


Assuntos
Serviços de Saúde do Indígena/normas , Neoplasias/terapia , Cuidados Paliativos/métodos , Assistência Terminal/psicologia , Idoso , Austrália/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Havaiano Nativo ou Outro Ilhéu do Pacífico , Neoplasias/psicologia
2.
Appl Microbiol Biotechnol ; 101(2): 871-886, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27872997

RESUMO

Monitoring the quality of drinking water is an important issue for public health. Two of the main objectives of the European Project µAQUA were (i) the development of specific probes to detect and quantify pathogens in drinking water and (ii) the design of standardized sampling programs of water from different sources in Europe in order to obtain sufficient material for downstream analysis. Our phylochip contains barcodes that specifically identify freshwater pathogens for enabling the detection of organisms that can be risks for human health. Monitoring for organisms with molecular tools is rapid, more accurate and more reliable than traditional methods. Rapid detection means that mitigation strategies come into play faster with less harm to the community and to humans. Samples were collected from several waters in France, Germany, Ireland, Italy and Turkey over 2 years. We present microarray results for the presence of freshwater pathogens from brackish and freshwater sites in Northern Germany, and cyanobacterial cell numbers inferred from these sites. In a companion study from the same samples, cyanobacterial toxins were analyzed using two methods and those sites with highest toxin values also had highest cell numbers as inferred from this microarray study.


Assuntos
Toxinas Bacterianas/análise , Cianobactérias/isolamento & purificação , Água Doce/microbiologia , Análise em Microsséries/métodos , Água do Mar/microbiologia , Toxinas Bacterianas/genética , Cianobactérias/classificação , Cianobactérias/genética , Alemanha , Humanos
3.
Sensors (Basel) ; 17(5)2017 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-28531156

RESUMO

Molecular techniques to detect organisms in aquatic ecosystems are being gradually considered as an attractive alternative to standard laboratory methods. They offer faster and more accurate means of detecting and monitoring species, with respect to their traditional homologues based on culture and microscopic counting. Molecular techniques are particularly attractive when multiple species need to be detected and/or are in very low abundance. This paper reviews molecular techniques based on whole cells, such as microscope-based enumeration and Fluorescence In-Situ Hybridization (FISH) and molecular cell-free formats, such as sandwich hybridization assay (SHA), biosensors, microarrays, quantitative polymerase chain reaction (qPCR) and real time PCR (RT-PCR). Those that combine one or several laboratory functions into a single integrated system (lab-on-a-chip) and techniques that generate a much higher throughput data, such as next-generation systems (NGS), were also reviewed. We also included some other approaches that enhance the performance of molecular techniques. For instance, nano-bioengineered probes and platforms, pre-concentration and magnetic separation systems, and solid-phase hybridization offer highly pre-concentration capabilities. Isothermal amplification and hybridization chain reaction (HCR) improve hybridization and amplification techniques. Finally, we presented a study case of field remote sensing of harmful algal blooms (HABs), the only example of real time monitoring, and close the discussion with future directions and concluding remarks.


Assuntos
Proliferação Nociva de Algas , Técnicas Biossensoriais , Ecossistema , Monitoramento Ambiental , Hibridização de Ácido Nucleico
4.
Environ Monit Assess ; 190(1): 42, 2017 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-29273852

RESUMO

Monitoring drinking water quality is an important public health issue. Two objectives from the 4 years, six nations, EU Project µAqua were to develop hierarchically specific probes to detect and quantify pathogens in drinking water using a PCR-free microarray platform and to design a standardised water sampling program from different sources in Europe to obtain sufficient material for downstream analysis. Our phylochip contains barcodes (probes) that specifically identify freshwater pathogens that are human health risks in a taxonomic hierarchical fashion such that if species is present, the entire taxonomic hierarchy (genus, family, order, phylum, kingdom) leading to it must also be present, which avoids false positives. Molecular tools are more rapid, accurate and reliable than traditional methods, which means faster mitigation strategies with less harm to humans and the community. We present microarray results for the presence of freshwater pathogens from a Turkish lake used drinking water and inferred cyanobacterial cell equivalents from samples concentrated from 40 into 1 L in 45 min using hollow fibre filters. In two companion studies from the same samples, cyanobacterial toxins were analysed using chemical methods and those dates with highest toxin values also had highest cell equivalents as inferred from this microarray study.


Assuntos
Água Potável/microbiologia , Monitoramento Ambiental/métodos , Lagos/microbiologia , Estações do Ano , Microbiologia da Água/normas , Qualidade da Água , Toxinas Bacterianas/análise , Cianobactérias/crescimento & desenvolvimento , Toxinas de Cianobactérias , Humanos , Lagos/química , Toxinas Marinhas/análise , Microcistinas/análise , Turquia
5.
J Phycol ; 51(1): 173-88, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26986267

RESUMO

The taxonomic assignment of Prorocentrum species is based on morphological characteristics; however, morphological variability has been found for several taxa isolated from different geographical regions. In this study, we evaluated species boundaries of Prorocentrum hoffmannianum and Prorocentrum belizeanum based on morphological and molecular data. A detailed morphological analysis was done, concentrating on the periflagellar architecture. Molecular analyses were performed on partial Small Sub-Unit (SSU) rDNA, partial Large Sub-Unit (LSU) rDNA, complete Internal Transcribed Spacer Regions (ITS1-5.8S-ITS2), and partial cytochrome b (cob) sequences. We concatenated the SSU-ITS-LSU fragments and constructed a phylogenetic tree using Bayesian Inference (BI) and maximum likelihood (ML) methods. Morphological analyses indicated that the main characters, such as cell size and number of depressions per valve, normally used to distinguish P. hoffmannianum from P. belizeanum, overlapped. No clear differences were found in the periflagellar area architecture. Prorocentrum hoffmannianum and P. belizeanum were a highly supported monophyletic clade separated into three subclades, which broadly corresponded to the sample collection regions. Subtle morphological overlaps found in cell shape, size, and ornamentation lead us to conclude that P. hoffmanianum and P. belizeanum might be considered conspecific. The molecular data analyses did not separate P. hoffmannianum and P. belizeanum into two morphospecies, and thus, we considered them to be the P. hoffmannianum species complex because their clades are separated by their geographic origin. These geographic and genetically distinct clades could be referred to as ribotypes: (A) Belize, (B) Florida-Cuba, (C1) India, and (C2) Australia.

6.
Nature ; 456(7219): 239-44, 2008 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-18923393

RESUMO

Diatoms are photosynthetic secondary endosymbionts found throughout marine and freshwater environments, and are believed to be responsible for around one-fifth of the primary productivity on Earth. The genome sequence of the marine centric diatom Thalassiosira pseudonana was recently reported, revealing a wealth of information about diatom biology. Here we report the complete genome sequence of the pennate diatom Phaeodactylum tricornutum and compare it with that of T. pseudonana to clarify evolutionary origins, functional significance and ubiquity of these features throughout diatoms. In spite of the fact that the pennate and centric lineages have only been diverging for 90 million years, their genome structures are dramatically different and a substantial fraction of genes ( approximately 40%) are not shared by these representatives of the two lineages. Analysis of molecular divergence compared with yeasts and metazoans reveals rapid rates of gene diversification in diatoms. Contributing factors include selective gene family expansions, differential losses and gains of genes and introns, and differential mobilization of transposable elements. Most significantly, we document the presence of hundreds of genes from bacteria. More than 300 of these gene transfers are found in both diatoms, attesting to their ancient origins, and many are likely to provide novel possibilities for metabolite management and for perception of environmental signals. These findings go a long way towards explaining the incredible diversity and success of the diatoms in contemporary oceans.


Assuntos
Diatomáceas/genética , Evolução Molecular , Genoma/genética , DNA de Algas/análise , Genes Bacterianos/genética , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Transdução de Sinais
7.
Aust Health Rev ; 38(4): 447-53, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25179506

RESUMO

OBJECTIVE: Respiratory diseases are a leading cause of morbidity and mortality in Indigenous Australians. However, there are limited approaches to specialist respiratory care in rural and remote communities that are culturally appropriate. A specialist Indigenous Respiratory Outreach Care (IROC) program, developed to address this gap, is described. METHODS: The aim of the present study was to implement, pilot and evaluate multidisciplinary specialist respiratory outreach medical teams in rural and remote Indigenous communities in Queensland, Australia. Sites were identified based on a perception of unmet need, burden of respiratory disease and/or capacity to use the clinical service and capacity building for support offered. RESULTS: IROC commenced in March 2011 and, to date, has been implemented in 13 communities servicing a population of approximately 43000 Indigenous people. Clinical service delivery has been possible through community engagement and capacity building initiatives directed by community protocols. CONCLUSION: IROC is a culturally sensitive and sustainable model for adult and paediatric specialist outreach respiratory services that may be transferrable to Indigenous communities across Queensland and Australia.


Assuntos
Relações Comunidade-Instituição , Assistência à Saúde Culturalmente Competente , Havaiano Nativo ou Outro Ilhéu do Pacífico , Doenças Respiratórias/etnologia , Serviços de Saúde Rural , Especialização , Acessibilidade aos Serviços de Saúde , Humanos , Comunicação Interdisciplinar , Projetos Piloto , Queensland , Doenças Respiratórias/terapia
8.
Harmful Algae ; 138: 102697, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39244232

RESUMO

A variety of shellfish toxin-producing Harmful Algal Blooms (HABs) occur every year in coastal temperate waters worldwide. These toxic HABs may cause lengthy (months) harvesting bans of mussels and other suspension feeding bivalves exposed to their blooms. To safeguard public health and the shellfish industry, European Union regulations request periodic monitoring of potentially toxic microalgae in seawater and phycotoxins in live bivalve molluscs from shellfish production areas. Monitoring of other toxic microalgae, e.g., fish killers, is based solely on cell counts. Morphological identification and quantification of microalgal cells with light microscopy is time-consuming, requires a good expertise, and accurate identification to species level (e.g., Pseudo-nitzschia species) may require electron microscopy. Toxicity varies among morphologically similar species; there are toxic and non-toxic strains of the same species. Molecular techniques using ribosomal DNA sequences offer a possibility to identify and detect precisely the potentially toxic genus/species. In an earlier project (MIDTAL), specific probes against rRNA sequences of all HAB taxa, known at the time of the project, affecting shellfish areas worldwide were designed, and those affecting Europe were tested and calibrated against rRNA extracts of clonal cultures and field samples. Microarray technology was adopted to relate to cell numbers the fluorescence signal from the reaction of all target species probes spotted in the microarray slides with those present in a single sample extract. The EMERTOX project aimed to develop a more automatic "Lab on a chip" (LOC) technology, including a non- (cell) disruptive water concentration system and biosensors for HAB cells detection. Here, calibration curves are presented against toxic microalgae (cultures and field samples) causing endemic and emerging toxicity events in Galicia (NW Spain) and Portugal. Results here relating cell numbers to electrochemical signals will be used in an early warning biosensor for toxic algae.


Assuntos
Técnicas Biossensoriais , Proliferação Nociva de Algas , Técnicas Biossensoriais/métodos , Calibragem , Microalgas , Animais , Toxinas Marinhas/análise , Monitoramento Ambiental/métodos
10.
Drug Alcohol Rev ; 41(7): 1499-1509, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35830355

RESUMO

INTRODUCTION: In November 2017, Central Queensland Public Health Unit launched the '10,000 Lives' initiative to reduce smoking prevalence in Central Queensland. The program partnered with local champions and other programs (e.g. 'Deadly Choices') to promote the use of smoking cessation services (e.g. Quitline) in Central Queensland. This study assesses the program's impact on Quitline use by participant demographics and Indigenous status. METHODS: We compared the number of referred individuals who participated in and completed the Quitline program, and quit smoking during 26-months before (July 2015 to August 2017) and after (November 2017 to December 2019) the '10,000 Lives' launch. We conducted an interrupted time series analysis of monthly referrals to and use of Quitline for Aboriginal and Torres Strait Islander peoples. RESULTS: Overall, 3207 individuals were referred to Quitline during the 26-months-post-launch compared to 1594 during 26-months-pre-launch period of '10,000 Lives'. The number of referred individuals who completed Quitline program increased by 330.7% and quit smoking by 308.3% in post-launch period. The increase was substantially higher among aged 45+ years, females and Aboriginal and Torres Strait Islander peoples. The result for referrals and use of Quitline was validated by interrupted time series analysis for Aboriginal and Torres Strait Islander peoples. DISCUSSION AND CONCLUSIONS: The '10,000 Lives' collaborative approach to partner with local champions and targeted smoking cessation programs was effective in increasing the use of Quitline and smoking cessation among all demographic groups, including Aboriginal and Torres Strait Islander peoples. This approach can be used in other regions to address higher smoking prevalence.


Assuntos
Serviços de Saúde do Indígena , Abandono do Hábito de Fumar , Feminino , Humanos , Havaiano Nativo ou Outro Ilhéu do Pacífico , Fumar/epidemiologia , Encaminhamento e Consulta , Prevalência
11.
EClinicalMedicine ; 36: 100919, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34142069

RESUMO

BACKGROUND: Liver disease and hepatocellular carcinoma (HCC) are important contributors to the mortality gap between Indigenous and non-Indigenous Australians. However, there is a lack of population based high quality data assessing the differences in HCC epidemiology and outcomes according to Indigenous status. The aim of this study was therefore to perform a large epidemiological study of HCC investigating differences between Indigenous and non-Indigenous Australians with HCC. METHODS: Study design was a retrospective cohort study. Data linkage methodology was used to link data from cancer registries with hospital separation summaries across three Australian jurisdictions during 2000-2017. Cumulative survival (Kaplan-Meier) and the differences in survival (Multivariable Cox-regression) by Indigenous status were assessed. FINDINGS: A total of 229 Indigenous and 3587 non-Indigenous HCC cases were included in the analyses. Significant epidemiological differences identified for Indigenous HCC cases included younger age at onset, higher proportion of females, higher rurality, lower socioeconomic status, and higher comorbidity burden (all p < 0.001). The distribution of cofactors was also significantly different for Indigenous Australians including higher prevalence of alcohol misuse, hepatitis B, and diabetes and more frequent presence of multiple HCC cofactors (all p < 0.001). Indigenous Australians received curative HCC therapies less frequently (6.6% vs. 14.5%, p < 0.001) and had poorer 5-year survival (10.0% vs. 17.3%, p < 0.001; unadjusted hazard ratio (HR) =1.42 96%CI 1.21-1.65) compared to non-Indigenous Australians. The strength of the association between indigenous status and survival was weaker and statistically non-significant after adjusting for rurality, comorbidity burden and lack of curative therapy (adjusted-HR=1.20 95%CI 0.97-1.47). INTERPRETATION: Such data provide a call to action to help design and implement health literacy, liver management and HCC surveillance programs for Indigenous people to help close the liver cancer mortality gap.

12.
Harmful Algae ; 92: 101703, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32113605

RESUMO

Monitoring drinking water quality is an important public health issue and pathogenic organisms present a particularly serious health hazard in freshwater bodies. However, many pathogenic bacteria, including cyanobacteria, and pathogenic protozoa can be swept into coastal lagoons and into near-shore marine environments where they continue to grow and pose a health threat to marine mammals and invertebrates. In this study, we tested the suitability of a phylochip (microarray for species detection) developed for freshwater pathogenic organisms to be applied to samples taken across a marine/freshwater interface at monthly intervals for two years. Toxic cyanobacteria and pathogenic protozoa were more numerous in a coastal lagoon than at the freshwater or marine site, indicating that this microarray can be used to detect the presence of these pathogens across a marine/freshwater interface and thus the potential for toxicity to occur within the entire watershed.


Assuntos
Cianobactérias , Água Doce , Animais , Qualidade da Água
13.
Biosensors (Basel) ; 10(12)2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33339199

RESUMO

Harmful algal blooms (HABs) are more frequent as climate changes and tropical toxic species move northward, especially along the Iberian Peninsula, a rich aquaculture area. Monitoring programs, detecting the presence of toxic algae before they bloom, are of paramount importance to protect ecosystems, aquaculture, human health and local economies. Rapid, reliable species identification methods using molecular barcodes coupled to biosensor detection tools have received increasing attention as an alternative to the legally required but impractical microscopic counting-based techniques. Our electrochemical detection system has improved, moving from conventional sandwich hybridization protocols using different redox mediators and signal probes with different labels to a novel strategy involving the recognition of RNA heteroduplexes by antibodies further labelled with bacterial antibody binding proteins conjugated with multiple enzyme molecules. Each change has increased sensitivity. A 150-fold signal increase has been produced with our newest protocol using magnetic microbeads (MBs) and amperometric detection at screen-printed carbon electrodes (SPCEs) to detect the target RNA of toxic species. We can detect as few as 10 cells L-1 for some species by using a fast (~2 h), simple (PCR-free) and cheap methodology (~2 EUR/determination) that will allow this methodology to be integrated into easy-to-use portable systems.


Assuntos
Monitoramento Ambiental , Proliferação Nociva de Algas , Técnicas Biossensoriais/métodos , Carbono , Ecossistema , Técnicas Eletroquímicas , Eletrodos , Humanos , Hibridização de Ácido Nucleico , Poluentes da Água/análise
14.
Artigo em Inglês | MEDLINE | ID: mdl-32106502

RESUMO

BACKGROUND: Sharing stories creates a space for respectful conversation and contributes to both knowledge and a sense of fellowship. This paper reflects on the experience of the research team in supporting a group of Aboriginal women to create safe spaces and to share their stories of healing, social and emotional wellbeing. METHODS: Secondary data of a study exploring community perceptions about cancer were analysed using the holistic model of Indigenous Wellbeing developed by the Rumbalara Aboriginal Cooperative (2008). Qualitative data were collected during yarning sessions with a group of Aboriginal women while creating a quilt. RESULTS: Four elements of the Indigenous Wellbeing model were identified: connectedness, sense of control, threats and relationship with the mainstream. The yarning sessions promoted dialogue, identified needs and supported the voices of the participants. A duality of forces (positive and negative) influencing community wellbeing was identified. CONCLUSION: This project highlights the need for spaces that support people and the community to express concerns, identify needs, propose solutions and begin a dialogue that encourages empowerment. Community-driven conversation and the identification of safe and empowering spaces can serve to empower social and emotional wellbeing.


Assuntos
Serviços de Saúde do Indígena , Havaiano Nativo ou Outro Ilhéu do Pacífico , Poder Psicológico , Adulto , Idoso , Emoções , Feminino , Humanos , Pessoa de Meia-Idade , Queensland , Adulto Jovem
15.
Appl Environ Microbiol ; 74(9): 2814-21, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18326673

RESUMO

DNA microarray technology offers the possibility to analyze microbial communities without cultivation, thus benefiting biodiversity studies. We developed a DNA phylochip to assess phytoplankton diversity and transferred 18S rRNA probes from dot blot or fluorescent in situ hybridization (FISH) analyses to a microarray format. Similar studies with 16S rRNA probes have been done determined that in order to achieve a signal on the microarray, the 16S rRNA molecule had to be fragmented, or PCR amplicons had to be <150 bp in length to minimize the formation of a secondary structure in the molecule so that the probe could bind to the target site. We found different results with the 18S rRNA molecule. Four out of 12 FISH probes exhibited false-negative signals on the microarray; eight exhibited strong but variable signals using full-length 18S RNA molecules. A systematic investigation of the probe's accessibility to the 18S rRNA gene was made using Prymenisum parvum as the target. Fourteen additional probes identical to this target covered the regions not tested with existing FISH probes. Probes with a binding site in the first 900 bp of the gene generated positive signals. Six out of nine probes binding in the last 900 bp of the gene produced no signal. Our results suggest that although secondary structure affected probe binding, the effect is not the same for the 18S rRNA gene and the 16S rRNA gene. For the 16S rRNA gene, the secondary structure is stronger in the first half of the molecule, whereas in the 18S rRNA gene, the last half of the molecule is critical. Probe-binding sites within 18S rRNA gene molecules are important for the probe design for DNA phylochips because signal intensity appears to be correlated with the secondary structure at the binding site in this molecule. If probes are designed from the first half of the 18S rRNA molecule, then full-length 18S rRNA molecules can be used in the hybridization on the chip, avoiding the fragmentation and the necessity for the short PCR amplicons that are associated with using the 16S rRNA molecule. Thus, the 18S rRNA molecule is a more attractive molecule for use in environmental studies where some level of quantification is desired. Target size was a minor problem, whereas for 16S rRNA molecules target size rather than probe site was important.


Assuntos
DNA Fúngico/genética , DNA Ribossômico/genética , Fungos/classificação , Fungos/genética , Análise em Microsséries/métodos , RNA Ribossômico 18S/genética , Modelos Moleculares , Conformação de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , Sondas de Oligonucleotídeos/genética , Sensibilidade e Especificidade
16.
Appl Environ Microbiol ; 74(17): 5305-16, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18621863

RESUMO

The microalgal class Prasinophyceae (Chlorophyta) contains several picoeukaryotic species, which are known to be common in temperate and cold waters and have been observed to constitute major fractions of marine picoplankton. However, reliable detection and classification of prasinophytes are mainly hampered by their small size and few morphological markers. Consequently, very little is known about the abundance and ecology of the members of this class. In order to facilitate the assessment of the abundance of the Prasinophyceae, we have designed and evaluated an 18S rRNA gene-targeted oligonucleotide microarray consisting of 21 probes targeting different taxonomic levels of prasinophytes. The microarray contains both previously published probes from other hybridization methods and new probes, which were designed for novel prasinophyte groups. The evaluation of the probe set was done under stringent conditions with 18S PCR fragments from 20 unialgal reference cultures used as positive targets. This microarray has been applied to assess the community composition of prasinophytes at Helgoland, an island in the North Sea where time series data are collected and analyzed daily but only for the nano- and microplankton-size fractions. There is no identification of prasinophytes other than to record them numerically in the flagellate fraction. The samples were collected every 2 weeks between February 2004 and December 2006. The study here demonstrates the potential of DNA microarrays to be applied as a tool for quick general monitoring of this important picoplanktonic algal group.


Assuntos
Clorófitas/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Fitoplâncton/genética , Clorófitas/classificação , Sondas de DNA , DNA de Algas/genética , Mar do Norte , Filogenia , Fitoplâncton/classificação , Reação em Cadeia da Polimerase , RNA Ribossômico 18S/genética , Sensibilidade e Especificidade
17.
Biosens Bioelectron ; 23(10): 1527-33, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18294835

RESUMO

Worldwide monitoring programs have been launched for the observation of phytoplankton composition and especially for harmful and toxic microalgae. Several molecular methods are currently used for the identification of phytoplankton but usually require transportation of samples to specialised laboratories. For the purpose of the monitoring of toxic algae, a multiprobe chip and a semi-automated rRNA biosensor for the in-situ detection of toxic algae were developed. Different materials for the electrodes and the carrier material were tested using single-electrode sensors and sandwich hybridisation that is based on species-specific rRNA probes. Phytoplankton communities consist of different species and therefore a biosensor consisting of a multiprobe chip with an array of 16 gold electrodes for the simultaneous detection of up to 14 target species was developed. The detection of the toxic algae is based on a sandwich hybridisation and an electrochemical detection method.


Assuntos
Técnicas Biossensoriais/instrumentação , Eletroquímica/instrumentação , Eucariotos/classificação , Eucariotos/isolamento & purificação , Toxinas Marinhas/análise , Microeletrodos , Transdutores , Técnicas Biossensoriais/métodos , Eletroquímica/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Eucariotos/genética , Reprodutibilidade dos Testes , Robótica/instrumentação , Robótica/métodos , Sensibilidade e Especificidade
18.
Harmful Algae ; 72: 25-35, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29413382

RESUMO

Harmful cyanobacterial blooms are a major threat to water quality and human health. Adequate risk assessment is thus required, which relies strongly on comprehensive monitoring. Here, we tested novel multi-probe RNA chips developed in the European project, µAqua, to determine the abundance of harmful cyanobacterial species and expression of selected toxin genes in six Dutch lakes. All of the targeted cyanobacterial genera, except for Planktothrix, were detected using the microarray, with predominance of Dolichospermum and Microcystis signals, of which the former was found across all sites and detected by the probes for Anabaena where it was formerly placed. These were confirmed by microscopic cell counts at three sites, whereas at the other sites, microscopic cell counts were lower. Probe signals of Microcystis showed larger variation across sites but also matched microscopic counts for three sites. At the other sites, microscopic counts were distinctly higher. We detected anatoxin-a in the water at all sites, but unfortunately no genes for this toxin were on this generation of the toxin array. For microcystins, we found none or low concentrations in the water, despite high population densities of putative microcystin producers (i.e. Microcystis, Dolichospermum). The described method requires further testing with a wider range of cyanobacterial communities and toxin concentrations before implementation into routine cyanobacterial risk assessment. Yet, our results demonstrate a great potential for applying multi-probe RNA chips for species as well as toxins to eutrophic waters with high cyanobacterial densities as a routine monitoring tool and as a predictive tool for toxin potential.


Assuntos
Cianobactérias/isolamento & purificação , Análise em Microsséries , RNA Bacteriano , Toxinas Bacterianas/genética , Cianobactérias/genética , Expressão Gênica , Proliferação Nociva de Algas , Lagos , Tipagem Molecular , Países Baixos , Sondas RNA , Microbiologia da Água
19.
Harmful Algae ; 75: 105-117, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29778220

RESUMO

Blooms of ichthyotoxic microalgae pose a great challenge to the aquaculture industry world-wide, and there is a need for fast and specific methods for their detection and quantification in monitoring programs. In this study, quantitative real-time PCR (qPCR) assays for the detection and enumeration of three ichthyotoxic flagellates: the dinoflagellate Karenia mikimotoi (Miyake & Kominami ex Oda) Hansen & Moestrup and the two raphidophytes Heterosigma akashiwo (Hada) Hada ex Hara & Chihara and Fibrocapsa japonica Toriumi & Takano were developed. Further, a previously published qPCR assay for the dinoflagellate Karlodinium veneficum (Ballantine) Larsen was used. Monthly samples collected for three years (Aug 2009-Jun 2012) in outer Oslofjorden, Norway were analysed, and the results compared with light microscopy cell counts. The results indicate a higher sensitivity and a lower detection limit (down to 1 cell L-1) for both qPCR assays. Qualitative and semi-quantitative results were further compared with those obtained by environmental 454 high throughput sequencing (HTS, metabarcoding) and scanning electron microscopy (SEM) examination from the same samplings. All four species were detected by qPCR and HTS and/or SEM in outer Oslofjorden (Aug 2009-Jun 2012); Karlodinium veneficum was present year-round, whereas Karenia mikimotoi, Heterosigma akashiwo and Fibrocapsa japonica appeared mainly during the autumn in all three years. This is the first observation of Fibrocapsa japonica in Norwegian coastal waters. This species has previously been recorded off the Swedish west coast and German Bight, which may suggest a northward dispersal.


Assuntos
Dinoflagellida/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Estramenópilas/isolamento & purificação , Proliferação Nociva de Algas , Toxinas Marinhas/análise , Microalgas/isolamento & purificação , Noruega
20.
Gene ; 406(1-2): 180-3, 2007 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-17919849

RESUMO

Marine phytoplanktons are highly dispersed with large population sizes and are often considered to be homogenous over their entire range. Thus, using this definition, one would predict that everything is everywhere for these microbes. However, recent molecular analyses have shown both spatial and temporal compartmentalisation in phytoplankton communities, thus calling into question the idea that everything is everywhere, especially if they do not share a global gene pool. Examples are present to document the range of biogeography that has been reported in the phytoplankton and a hypothesis as to how this relates to species evolution on a geological time scale is provided.


Assuntos
Biodiversidade , Pool Gênico , Fitoplâncton/genética , Diatomáceas , Eucariotos , Especiação Genética , Geografia , Filogenia
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