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1.
Br J Nurs ; 30(4): S3, 2021 Feb 25.
Article in English | MEDLINE | ID: mdl-33641397
2.
Eur J Protistol ; 72: 125645, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31790921

ABSTRACT

Arcellinida (lobose testate amoebae) are abundant and diverse in many ecosystems, especially in moist to aquatic environments. Molecular phylogeny has shown that overall test morphology (e.g., spherical or elongate) is generally conserved in Arcellinida lineages, but the taxonomic value of other traits (e.g., size, ornamentation, mixotrophy/heterotrophy metabolism type) has not been systematically evaluated. Morphological and physiological traits that correspond to genetic differences likely represent adaptive traits of ecological significance. We combined high-resolution phylogenetics (NAD9-NAD7 genes) and advanced morphometrics to assess the phylogenetic signal of morphological traits of a group of elongate Difflugia species (Arcellinida). The phylogenetic analyses revealed two clades which could be reliably separated by test size and the presence/absence of mixotrophy. Differences in test size may reflect trophic level, with smaller organisms occupying lower trophic levels. In addition to having larger tests, elongate mixotrophic Difflugia are characterised by wide, flat bases and an inflation of the lower two thirds of their test. These morphological traits may provide additional volume for endosymbionts and/or increased surface area to aid light transmission. Our results showcase greater diversity within the elongate Difflugia and highlight morphological traits of ecological and evolutionary significance.


Subject(s)
Amoebozoa/classification , Amoebozoa/cytology , Phylogeny , Amoebozoa/metabolism , Energy Metabolism , Protozoan Infections/genetics , Species Specificity
3.
Front Physiol ; 10: 941, 2019.
Article in English | MEDLINE | ID: mdl-31396106

ABSTRACT

Drosophila suzukii (Matsumara) also called Spotted Wing Drosophila (SWD), is an invasive pest species originally from Asia that has now spread widely across Europe and North America. The majority of drosophilids including the best known Drosophila melanogaster only breed on decaying fruits. On the contrary, the presence of a strong serrated ovipositor and behavioural and metabolic adaptations allow D. suzukii to lay eggs inside healthy, ripening fruits that are still on the plant. Here we present an analysis of the rhythmic locomotor activity behaviour of D. suzukii under several laboratory settings. Moreover, we identify the canonical clock neurons in this species by reporting the expression pattern of the major clock proteins in the brain. Interestingly, a fundamentally similar organisation of the clock neurons network between D. melanogaster and D. suzukii does not correspond to similar characteristics in rhythmic locomotor activity behaviour.

4.
PeerJ ; 6: e4850, 2018.
Article in English | MEDLINE | ID: mdl-29915687

ABSTRACT

Frame Lake, located within the city of Yellowknife, Northwest Territories, Canada, has been identified as requiring significant remediation due to its steadily declining water quality and inability to support fish by the 1970s. Former gold mining operations and urbanization around the lake have been suspected as probable causes for the decline in water quality. While these land-use activities are well documented, little information is available regarding their impact on the lake itself. For this reason, Arcellinida, a group of shelled protozoans known to be reliable bioindicators of land-use change, were used to develop a hydroecological history of the lake. The purpose of this study was to use Arcellinida to: (1) document the contamination history of the lake, particularly related to arsenic (As) associated with aerial deposition from mine roaster stacks; (2) track the progress of water quality deterioration in Frame Lake related to mining, urbanization and other activities; and (3) identify any evidence of natural remediation within the lake. Arcellinida assemblages were assessed at 1-cm intervals through the upper 30 cm of a freeze core obtained from Frame Lake. The assemblages were statistically compared to geochemical and loss-on-ignition results from the core to document the contamination and degradation of conditions in the lake. The chronology of limnological changes recorded in the lake sediments were derived from 210Pb, 14C dating and known stratigraphic events. The progress of urbanization near the lake was tracked using aerial photography. Using Spearman correlations, the five most significant environmental variables impacting Arcellinida distribution were identified as minerogenics, organics, As, iron and mercury (p < 0.05; n = 30). Based on CONISS and ANOSIM analysis, three Arcellinida assemblages are identified. These include the Baseline Limnological Conditions Assemblage (BLCA), ranging from 17-30 cm and deposited in the early Holocene >7,000 years before present; the As Contamination Assemblage (ACA), ranging from 7-16 cm, deposited after ∼1962 when sedimentation began in the lake again following a long hiatus that spanned to the early Holocene; and the Eutrophication Assemblage (EA), ranging from 1-6 cm, comprised of sediments deposited after 1990 following the cessation of As and other metal contaminations. The EA developed in response to nutrient-rich waters entering the lake derived from the urbanization of the lake catchment and a reduction in lake circulation associated with the development at the lake outlet of a major road, later replaced by a causeway with rarely open sluiceways. The eutrophic condition currently charactering the lake-as evidenced by a population explosion of eutrophication indicator taxa Cucurbitella tricuspis-likely led to a massive increase in macrophyte growth and winter fish-kills. This ecological shift ultimately led to a system dominated by Hirudinea (leeches) and cessation of the lake as a recreational area.

5.
PLoS One ; 13(6): e0199872, 2018.
Article in English | MEDLINE | ID: mdl-29953559

ABSTRACT

We examined late Holocene (ca. 3300 yr BP to present-day) climate variability in the central Northwest Territories (Canadian Subarctic) using a diatom and sedimentological record from Danny's Lake (63.48ºN, 112.54ºW), located 40 km southwest of the modern-day treeline. High-resolution sampling paired with a robust age model (25 radiocarbon dates) allowed for the examination of both lake hydroecological conditions (30-year intervals; diatoms) and sedimentological changes in the watershed (12-year intervals; grain size records) over the late Holocene. Time series analysis of key lake ecological indicators (diatom species Aulacoseira alpigena, Pseudostaurosira brevistriata and Achnanthidium minutissimum) and sedimentological parameters, reflective of catchment processes (coarse silt fraction), suggests significant intermittent variations in turbidity, pH and light penetration within the lake basin. In the diatom record, we observed discontinuous periodicities in the range of ca. 69, 88-100, 115-132, 141-188, 562, 750 and 900 years (>90% and >95% confidence intervals), whereas the coarse silt fraction was characterized by periodicities in the >901 and <61-year range (>95% confidence interval). Periodicities in the proxy data from the Danny's Lake sediment core align with changes in total solar irradiance over the past ca. 3300 yr BP and we hypothesize a link to the Suess Cycle, Gleissberg Cycle and Pacific Decadal Oscillation via occasional inland propagation of shifting air masses over the Pacific Ocean. This research represents an important baseline study of the underlying causes of climate variability in the Canadian Subarctic and provides details on the long-term climate variability that has persisted in this region through the past three thousand years.


Subject(s)
Climate Change , Diatoms , Fossils , Lakes , Canada
6.
Microb Ecol ; 76(3): 680-694, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29504072

ABSTRACT

Arcellinida (testate lobose amoebae), a group of benthic protists, were examined from 46 sediment-water interface samples collected from oligotrophic Oromocto Lake, New Brunswick, Canada. To assess (1) assemblage homogeneity at a sub-meter spatial scale and (2) the necessity for collecting samples from multiple stations during intra-lake surveys; multiple samples were collected from three stations (quadrats 1, 2, and 3) across the north basin of Oromocto Lake, with quadrat 1 (n = 16) being the furthest to the west, quadrat 2 (n = 15) situated closer to the center of the basin, and quadrat 3 (n = 15) positioned 300 m south of the mouth of Dead Brook, an inlet stream. Results from cluster analysis and non-metric multidimensional scaling (NMDS) analysis identified two major Arcellinida assemblages, A1 and A2, the latter containing two sub-assemblages (A2a and A2b). Redundancy analysis and variance partitioning results indicated that seven statistically significant environmental variables (K, S, Sb, Ti, Zn, Fe, and Mn) explained 41.5% of the total variation in the Arcellinida distribution. Iron, Ti and K, indicators of detrital runoff, had the greatest influence on assemblage variance. The results of this study reveal that closely spaced samples (~ 10 cm) in an open-water setting are comprised of homogenous arcellinidan assemblages, indicating that replicate sampling is not required. The results, however, must be tempered with respect to the various water properties and physical characteristics that comprise individual lakes as collection of several samples may likely be necessary when sampling multiple sites of a lake basin characterized by varying water depths (e.g., littoral zone vs. open water), or lakes impacted by geogenic or anthropogenic stressors (e.g., eutrophication, or industrial contamination).


Subject(s)
Amoeba/isolation & purification , Lakes/parasitology , Amoeba/classification , Amoeba/genetics , Biodiversity , Canada , Environmental Monitoring , Geologic Sediments/chemistry , Geologic Sediments/parasitology , Iron/analysis , Lakes/chemistry , Phylogeny
7.
Eur J Protistol ; 60: 13-27, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28688372

ABSTRACT

Testate amoeba-derived transfer functions are frequently used in peatland palaeohydrological studies and involve the development of training sets from surficial peats. However, within acrotelmic peats, considerable vertical variation in assemblage composition can occur, particularly along Sphagnum stems, which may limit the representation of the associated 'contemporary' testate amoeba samples as analogues for the peatland surface. This paper presents contiguous testate amoeba assemblage data from nine monoliths collected from different peatland microforms (hummock, hollow, lawn) in three Sphagnum dominated ombrotrophic peatlands in Ontario and Quebec, eastern Canada. The aim is to: (i) gain a greater understanding of the vertical distribution of xerophilous/hygrophilous taxa along Sphagnum stems; (ii) determine the vertical extent of live/encysted taxa along this gradient; and (iii) assess the significance of this distribution on surface sampling protocols. The results show that testate amoeba communities in the uppermost acrotelmic peat layers display considerable variability. This may reflect a complex interplay of abiotic and biotic controls, including moisture, temperature, light and other characteristics, food availability, and mineral particle availability for test construction. These findings underline the complexity of testate amoeba community structure and highlight the importance of analysing both living and dead Sphagnum stem sections when developing calibration sets.


Subject(s)
Amoeba/physiology , Biodiversity , Soil/parasitology , Amoeba/classification , Hydrology , Paleontology , Population Dynamics , Sphagnopsida/parasitology , Wetlands
8.
Br J Nurs ; 25(10): S30, 2016.
Article in English | MEDLINE | ID: mdl-27231749
9.
Br J Nurs ; 25(10): S3, 2016.
Article in English | MEDLINE | ID: mdl-27231748
10.
Microb Ecol ; 72(1): 130-149, 2016 07.
Article in English | MEDLINE | ID: mdl-27026100

ABSTRACT

Arcellininids (testate amoebae) were examined from 61 surface sediment samples collected from 59 lakes in the vicinity of former gold mines, notably Giant Mine, near Yellowknife, Northwest Territories, Canada to determine their utility as bioindicators of arsenic (As), which occurs both as a byproduct of gold extraction at mines in the area and ore-bearing outcrops. Cluster analysis (Q-R-mode) and detrended correspondence analysis (DCA) reveal five arcellininid assemblages, three of which are related to varying As concentrations in the sediment samples. Redundancy analysis (RDA) showed that 14 statistically significant environmental parameters explained 57 % of the variation in faunal distribution, while partial RDA indicated that As had the greatest influence on assemblage variance (10.7 %; p < 0.10). Stress-indicating species (primarily centropyxids) characterized the faunas of samples with high As concentrations (median = 121.7 ppm, max > 10000 ppm, min = 16.1 ppm, n = 32), while difflugiid dominated assemblages were prevalent in substrates with relatively low As concentrations (median = 30.2 ppm, max = 905.2 ppm, min = 6.3 ppm, n = 20). Most of the lakes with very high As levels are located downwind (N and W) of the former Giant Mine roaster stack where refractory ore was roasted and substantial quantities of As were released (as As2O3) to the atmosphere in the first decade of mining. This spatial pattern suggests that a significant proportion of the observed As, in at least these lakes, are industrially derived. The results of this study highlight the sensitivity of Arcellinina to As and confirm that the group has considerable potential for assessing the impact of As contamination on lakes.


Subject(s)
Amoeba/metabolism , Arsenic/analysis , Environmental Monitoring , Geologic Sediments/chemistry , Geologic Sediments/microbiology , Amoeba/classification , Amoeba/isolation & purification , Arsenic Trioxide , Arsenicals , Canada , Cluster Analysis , Gold , Lakes/chemistry , Mining , Oxides
12.
Ecancermedicalscience ; 9: 509, 2015.
Article in English | MEDLINE | ID: mdl-25729422

ABSTRACT

The UK Oncology Nursing Society's (UKONS) annual conference focused on three major themes. These were 'Living With and Beyond Cancer', 'Patient Information and Support', and 'Innovations in Treatment and Care'. It featured a wide range of presentations, industry satellites, exhibitions, poster discussions. and workshops. Presenters ranged from those eminent in their particular field to those gracing the speaker's podium for the first time. The rich variety of presentations covered policy, cancer trends, clinical developments, care initiatives, personal development, and advances in practice. There was a strong emphasis on skills, knowledge, values, and attitudes, with the most junior and novice nurses mixing with experienced and highly esteemed practitioners.

14.
Br J Nurs ; 23(16): S4, S6, S8 passim, 2014.
Article in English | MEDLINE | ID: mdl-25203854

ABSTRACT

Chemotherapy is increasingly being administered as a treatment for cancer and with it are a number of possible side effects. One, which has a negative impact on a patient's quality of life and their self-esteem, is that of chemotherapy-induced alopecia (CIA). A side effect of which, for some, could be prevented by the use of scalp cooling, dependent on the regimen being administered and patient choice. This article explores the issue of CIA from the patient's perspective and scalp cooling as a preventative measure, along with a review of the evidence around the risk associated with developing scalp metastases following scalp cooling. It also discusses why scalp cooling should be available for both male and female patients; along with the potential impact scalp cooling may have on clinical areas delivering chemotherapy.


Subject(s)
Alopecia/chemically induced , Alopecia/prevention & control , Antineoplastic Agents/adverse effects , Hypothermia, Induced/methods , Scalp , Alopecia/psychology , Female , Hair/growth & development , Humans , Male , Neoplasms/drug therapy , Patient Selection , Sex Factors
15.
Ecancermedicalscience ; 8: 419, 2014.
Article in English | MEDLINE | ID: mdl-24761160

ABSTRACT

This paper presents the development of a pathway at a cancer unit in Northern England. The pathway aimed to ensure that patients with early breast cancer who were receiving Trastuzumab did so in a safe manner. This was achieved by developing a multiprofessional pathway, which crossed traditional boundaries to ensure the patient received the best care available. This paper describes the patient's perception of the pathway obtained through a patient satisfaction survey and suggestions for its future direction.

16.
Protist ; 165(3): 305-16, 2014 May.
Article in English | MEDLINE | ID: mdl-24742928

ABSTRACT

Arcellacea (testate lobose amoebae) are important lacustrine environmental indicators that have been used in paleoclimatic reconstructions, assessing the effectiveness of mine tailings pond reclamation projects and for studying the effects of land use change in rural, industrial and urban settings. Recognition of ecophenotypically significant infra-specific 'strains' within arcellacean assemblages has the potential to enhance the utility of the group in characterizing contemporary and paleoenvironments. We present a novel approach which employs statistical tools to investigate the environmental and taxonomic significance of proposed strains. We test this approach on two identified strains: Difflugia protaeiformis Lamarck strain 'acuminata' (DPA), characterized by fine grained agglutination, and Difflugia protaeiformis Lamarck strain 'claviformis' (DPC), characterized by coarse grained agglutination. Redundancy analysis indicated that both organisms are associated with similar environmental variables. No relationship was observed between substrate particle size and abundance of DPC, indicating that DPC has a size preference for xenosomes during test construction. Thus DPC should not be designated as a distinct strain but rather form a species complex with DPA. This study elucidates the need to justify the designation of strains based on their autecology in addition to morphological stability.


Subject(s)
Amoeba/classification , Ecosystem , Amoeba/genetics , Amoeba/ultrastructure , Biodiversity , Canada , Cluster Analysis , Environmental Monitoring , Phylogeny
17.
Microb Ecol ; 68(2): 299-313, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24728526

ABSTRACT

Winter deicing operations occur extensively in mid- to high-latitude metropolitan regions around the world and result in a significant reduction in road accidents. Deicing salts can, however, pose a major threat to water quality and aquatic organisms. In this paper, we examine the utility of Arcellacea (testate amoebae) for monitoring lakes that have become contaminated by winter deicing salts, particularly sodium chloride. We analysed 50 sediment samples and salt-related water property variables (chloride concentrations; conductivity) from 15 lakes in the Greater Toronto Area and adjacent areas of southern Ontario, Canada. The sampled lakes included lakes in proximity to major highways and suburban roads and control lakes in forested settings away from road influences. Samples from the most contaminated lakes, with chloride concentrations in excess of 400 mg/l and conductivities of >800 µS/cm, were dominated by species typically found in brackish and/or inhospitable lake environments and by lower faunal diversities (lowest Shannon diversity index values) than samples with lower readings. Q-R-mode cluster analysis and detrended correspondence analysis (DCA) resulted in the recognition of four assemblage groupings. These reflect varying levels of salt contamination in the study lakes, along with other local influences, including nutrient loading. The response to nutrients can, however, be isolated if the planktic eutrophic indicator species Cucurbitella tricuspis is removed from the counts. The findings show that the group has considerable potential for biomonitoring in salt-contaminated lakes, and their presence in lake sediment cores may provide significant insights into long-term benthic community health, which is integral for remedial efforts.


Subject(s)
Amoeba/growth & development , Environmental Monitoring/methods , Sodium Chloride/analysis , Water Pollutants, Chemical/analysis , Amoeba/isolation & purification , Cluster Analysis , Lakes/chemistry , Lakes/microbiology , Ontario
19.
Br J Nurs ; 22(17): S6 -12, 2013.
Article in English | MEDLINE | ID: mdl-24067273

ABSTRACT

AIMS: This article reviews the efficacy and place in therapy of dexrazoxane (Savene®) for the treatment of anthracycline extravasation, highlighting the lack of inclusion of Savene in most UK cancer network and organisational treatment guidelines. Here we offer advice to nurses on making a case to ensure the availability of Savene. KEY FINDINGS: In 2010, the UK National Extravasation Information Service (NEXIS) green card scheme reported that anthracyclines were the second most common agent involved in extravasations, but they carry the greatest risk to the patient because of their potentially serious consequences. Anthracycline extravasations therefore require prompt and effective treatment. Due to the infrequent occurrence of anthracycline extravasations, their accidental nature and ethical considerations, conducting randomised controlled clinical trials in this therapy area is not possible. As treatment decisions should always be made on patient-specific factors, health professionals need to demonstrate the rationale for choosing a particular course of action when presented with an anthracycline extravasation, especially when we are moving into an era of increased medical litigation. There are several possible treatment options, some of which require demonstrable local core competencies in order to be considered for a particular patient. Based on the available evidence, Savene-the only licensed antidote-is recommended as an effective management strategy for anthracycline extravasation and should be made available in all settings where chemotherapy is administered. However, a high percentage of nurses administering chemotherapy still do not have access to Savene, as it has not been included in their local guidelines for the management of extravasations. Thus, in a large part of the UK, this important treatment option is not available, leaving a significant unmet need (Figure 1). CONCLUSIONS: As nurses play a key role in the prevention, detection, and management of extravasations, they should also assume a key role in ensuring that their local protocols include all appropriate management strategies. Where appropriate, if Savene is not included in the treatment guidelines, nurses should feel empowered to encourage their trust and Specialist Commissioning Groups (SCGs) to make it available, and thus minimise the serious risks associated with anthracycline extravasations.


Subject(s)
Anthracyclines/adverse effects , Antineoplastic Agents/adverse effects , Dexrazoxane/therapeutic use , Extravasation of Diagnostic and Therapeutic Materials/drug therapy , Extravasation of Diagnostic and Therapeutic Materials/nursing , Neoplasms/drug therapy , Oncology Nursing/standards , Topoisomerase II Inhibitors/therapeutic use , Extravasation of Diagnostic and Therapeutic Materials/prevention & control , Humans , Practice Guidelines as Topic , Risk Factors , United Kingdom
20.
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