135 research outputs found
Recent occurrence of Cylindrospermopsis raciborskii, in Waikato lakes of New Zealand.
Cylindrospermopsis raciborskii is a toxin-producing species of cyanobacteria that in autumn 2003 was recorded for the first time in three shallow (max. depth ≤5 m) Waikato lakes and a hydro-electric dam on the Waikato River, New Zealand. It formed water blooms at densities >100 000 cells/ml in Lakes Waahi and Whangape. Net rates of population growth >0.2 day-1 were recorded for C. raciborskii in Lakes Ngaroto, Waahi, and Karapiro, based on comparisons of low numbers (detection of cells/ml) from initial samples and its presence at bloom densities (>15 000 cells/ml) in the subsequent sample "x"-"y" days later. C. raciborskii may be well adapted to rapid proliferation in the Waikato lakes, which are eutrophic to hypertrophic, with high light attenuation, and where nitrogen (N) fixation may provide it with a competitive advantage over non-nitrogen fixing algae under N-limited conditions
Key Factors to Maintaining Treatment Fidelity in an Improving Access to Psychological Therapies (IAPT) Model of CBT
The aim of this contribution is to provide evidence and greater theoretical understanding of the relationship between key factors that maintain treatment fidelity in CBT, outside of research settings. This spans decades in CBT training, supervision and practice, contributing new terms, concepts, models and clinical recommendations. The series culminates by focusing on Improving Access to Psychological Therapies (IAPT). A coherent body of work emerges, when an ‘empirically-grounded clinically interventions’ approach is applied. This uses practice-based research, pilot data and preliminary studies, combined with original empirical evidence.
Aims are achieved by defining and appraising five topics - Treatment Fidelity, Service-Model Fidelity, Training, Clinical Supervision and Service Framework. Once their key functions are established, their inter-relatedness emerges. The rationale has a basis in findings that clinical outcomes in research do not always translate into services, despite insignificant demographic differences and more experienced practitioners in services. This hypothesises, services with more variables that increase treatment fidelity to known interventions, will be linked to superior clinical outcome. Whilst drilling deeper into key concepts at one level, the overarching theme remains the tension between outcome research in CBT and its failure to translate into standard clinical services. This historical lack of replication was a factor in the modernisation agenda of IAPT. Three broad recommendations and implications for future research are concluded from the series.
First, adhering to a High Dose Narrow/Bandwidth (HD/NB) model (Cromarty 2016), increasing the dose of the primary intervention allows IAPT practitioners to closer match treatment fidelity and clinical outcomes of research trials. The Australian IAPT contributions explicitly showcase this, supporting the hypothesis that services with increased treatment fidelity yield superior clinical outcomes.
Secondly, HD/NB interventions must be supported by Service-Model Fidelity (Cromarty 2016). The delivery system in which HD/NB principles operate is equally important. This recommendation for integrating clinical improvement and service-redesign models, notes Treatment Fidelity is not guaranteed in clinical services with training, supervision and best-practice alone. Placed within an optimised service model such as IAPT, the joint strengths of key variables are amplified. Further research on service model being a possible factor of improved clinical outcome is recommended.
Thirdly, if known problems translating research into clinical practice persist, additional research closing the gap, can originate from the clinical practice! CBT has an actual empirical basis in clinical observation with additional theoretical aspects, researching and treating numerous variables, including psychosocial and psychological processes. CBT clinical practice possesses several overlapping features with single-case methodology. Small scale, service-based studies allow convenient samples, with high inference and low numbers. They have high clinical and face validity with the ability to study individual change processes. The advent of IAPT services allows a more robust two-way process to augment controlled research. They are ideal grounds for translating research findings into services due to inexorably linked variables, combining to improve treatment fidelity. This constitutes a continual two-way process by recipient IAPT services increasing the empirical basis of practice-based research. This can contribute back into the wider evidence base to inform future large-scale research
Attention Network Dysfunctions in Lewy Body Dementia and Alzheimer’s Disease
\ua9 2024 by the authors.Background: Attention deficits are notable in Lewy body dementia (LBD) and in Alzheimer’s disease (AD). In this study, we combined functional magnetic resonance imaging (fMRI) and electroencephalograph (EEG) to detect neural correlates of attention dysfunctions in LBD and AD. Methods: We recruited 33 patients with LBD, 15 patients with AD and 19 elderly healthy controls. The participants performed the modified Attention Network Task (ANT) to investigate the attention dysfunctions. Results: We found that LBD had alerting attention deficits and AD showed apparent orienting attention dysfunctions, while LBD and AD maintained relatively normal executive/conflict attention. Based on source-level EEG analyses, LBD had frontal-central deficits for alerting attention while AD showed inferior frontal and precentral impairments for orienting attention. In addition, the insular and inferior frontal areas were hyper-activated in LBD and AD for executive/conflict attention. Apart from these areas, LBD showed activity in the complementary temporal-central-occipital network for the modified ANT task. Furthermore, the oscillational sources for the ANT effects indicated that the alpha and theta bands were partly impaired in dementia patients. Conclusions: In summary, using source-localised EEG, we found that attention dysfunctions in LBD and AD engaged different neural networks
Relationships between plasma amino acid concentrations and blood pressure in South Africans of African descent
Oral supplementation with the amino acid arginine, the precursor of the vasodilator nitric oxide (NO), is associated with a reduction in blood pressure (BP). However, it is uncertain whether a decreased plasma arginine concentration predicts increases in BP. We assessed the relationship between fasting plasma arginine or other amino acid concentrations and 24 hour ambulatory BP in 75 nevertreated participants recruited from the Johannesburg area, 55 of whom were male. Plasma amino acid concentrations were measured with high performance liquid chromatography-mass-spectrometry. Plasma arginine concentrations were not inversely correlated with ambulatory BP. However, plasma arginine concentrations were increased in 36 participants with a mean daytime systolic BP >140 mm Hg (61 ± 17 μmol/L) as compared to the remaining participants (54 ± 15 μmol/L, p‹0.05). Moreover, plasma arginine concentrations were positively correlated with 24-hour diastolic BP (r=0.26, p‹0.05). In males with a BMI‹30kg/m2, plasma arginine concentrations were positively correlated with both night diastolic (r=0.46, p‹0.005) and systolic (r=0.42, p‹0.005) BP. In a multivariate model with adjustments for age gender, body mass index, and other amino acid concentrations, plasma arginine concentrations were independently and positively associated with night diastolic BP (p‹0.05). In conclusion plasma arginine concentrations are positively associated with ambulatory BP in a group of participants of African descent in South Africa. These data do not support the notion that deficiencies of arginine, the amino acid substrate for NO, are related to increases in BP in groups of African ancestry living in South Africa. However, as with other ethnic groups, the positive relationship between plasma arginine concentrations and BP suggests a reduced capacity to utilise the amino acid substrate for NO synthesis
Attention network dysfunctions in Lewy body dementia and Alzheimer’s disease
Background: Attention deficits are notable in Lewy body dementia (LBD) and in Alzheimer’s disease (AD). In this study, we combined functional magnetic resonance imaging (fMRI) and electroencephalograph (EEG) to detect neural correlates of attention dysfunctions in LBD and AD. Methods: We recruited 33 patients with LBD, 15 patients with AD and 19 elderly healthy controls. The participants performed the modified Attention Network Task (ANT) to investigate the attention dysfunctions. Results: We found that LBD had alerting attention deficits and AD showed apparent orienting attention dysfunctions, while LBD and AD maintained relatively normal executive/conflict attention. Based on source-level EEG analyses, LBD had frontal-central deficits for alerting attention while AD showed inferior frontal and precentral impairments for orienting attention. In addition, the insular and inferior frontal areas were hyper-activated in LBD and AD for executive/conflict attention. Apart from these areas, LBD showed activity in the complementary temporal-central-occipital network for the modified ANT task. Furthermore, the oscillational sources for the ANT effects indicated that the alpha and theta bands were partly impaired in dementia patients. Conclusions: In summary, using source-localised EEG, we found that attention dysfunctions in LBD and AD engaged different neural networks
Maintenance durvalumab after first-line chemotherapy in patients with HER2-negative advanced oesophago-gastric adenocarcinoma:results from the randomised PLATFORM study
Background PLAnning Treatment For Oesophago-gastric Cancer: a Randomised Maintenance Therapy Trial (PLATFORM) is an adaptive phase II study assessing the role of maintenance therapies in advanced oesophago-gastric (OG) adenocarcinoma. We evaluated the role of the anti-programmed death-ligand 1 (PD-L1) inhibitor durvalumab in these patients. Patients and methods Patients with human epidermal growth factor receptor 2-negative locally advanced or metastatic OG adenocarcinoma with disease control or response to 18 weeks of platinum-based first-line chemotherapy were randomised to active surveillance or maintenance durvalumab. The primary endpoint was progression-free survival (PFS). Safety was assessed in all patients who had commenced surveillance visits or received at least one dose of durvalumab. Exploratory survival analyses according to PD-L1 Combined Positive Score (CPS) and immune (biomarker-positive) or angiogenesis dominant (biomarker-negative) tumour microenvironment (TME) phenotypes were conducted. Results Between March 2015 and April 2020, 205 patients were randomised to surveillance (n = 100) and durvalumab (n = 105). No significant differences were seen in PFS [hazard ratio (HR) 0.84, P = 0.13] and overall survival (OS; HR 0.98, P = 0.45) between surveillance and durvalumab. Five patients randomised to durvalumab demonstrated incremental radiological responses compared with none with surveillance. Treatment-related adverse events occurred in 77 (76.2%) durvalumab-assigned patients. A favourable effect in OS with durvalumab over surveillance in CPS ≥5 and immune biomarker-positive patients was observed compared with CPS <5 and biomarker-negative subgroups, respectively: CPS ≥5 versus <5: HR 0.63, 95% confidence interval (CI) 0.32-1.22 versus HR 0.93, 95% CI 0.44-1.96; biomarker-positive versus negative: HR 0.60, 95% CI 0.29-1.23 versus HR 0.84, 95% CI 0.42-1.65. Conclusion Maintenance durvalumab does not improve PFS in patients with OG adenocarcinoma who respond to first-line chemotherapy but induced incremental radiological responses in a subset of patients. TME characterisation could refine patient selection for anti-PD-L1 therapy above PD-L1 CPS alone.</p
Functional and structural brain network correlates of visual hallucinations in Lewy body dementia
Visual hallucinations are a common feature of Lewy body dementia. Previous studies have shown that visual hallucinations are highly specific in differentiating Lewy body dementia from Alzheimer’s disease dementia and Alzheimer-Lewy body mixed pathology cases. Computational models propose that impairment of visual and attentional networks is aetiologically key to the manifestation of visual hallucinations symptomatology. However, there is still a lack of experimental evidence on functional and structural brain network abnormalities associated with visual hallucinations in Lewy body dementia. We used EEG source localisation and Network Based Statistics to assess differential topographical patterns in Lewy body dementia between 25 participants with visual hallucinations and 17 participants without hallucinations. Diffusion tensor imaging was used to assess structural connectivity between thalamus, basal forebrain and cortical regions belonging to the functionally affected network component in the hallucinating group, as assessed with Network Based Statistics. Number of white matter streamlines within the cortex and between subcortical and cortical regions was compared between hallucinating and not hallucinating groups and correlated with average EEG source connectivity of the affected subnetwork. Moreover, modular organisation of the EEG source network was obtained, compared between groups, and tested for correlation with structural connectivity. Network analysis showed that compared to non-hallucinating patients, those with hallucinations feature consistent weakened connectivity within the visual ventral network, and between this network and default mode and ventral attentional networks, but not between or within attentional networks. The occipital lobe was the most functionally disconnected region. Structural analysis yielded significantly affected white matter streamlines connecting the cortical regions to the nucleus basalis of Meynert and the thalamus in hallucinating compared to not hallucinating patients. The number of streamlines in the tract between the basal forebrain and the cortex correlated with cortical functional connectivity in non-hallucinating patients, whilst a correlation emerged for the white matter streamlines connecting the functionally affected cortical regions in the hallucinating group. This study proposes, for the first time, differential functional networks between hallucinating and not hallucinating Lewy body dementia patients, and provides an empirical evidence for existing models of visual hallucinations. Specifically, the outcome of the present study shows that the hallucinating condition is associated with functional network segregation in Lewy body dementia and supports the involvement of the cholinergic system as proposed in the current literature
Experiences and perceptions of people with headache: a qualitative study
BACKGROUND: Few qualitative studies of headache have been conducted and as a result we have little in-depth understanding of the experiences and perceptions of people with headache. The aim of this paper was to explore the perceptions and experiences of individuals with headache and their experiences of associated healthcare and treatment. METHODS: A qualitative study of individuals with headache, sampled from a population-based study of chronic pain was conducted in the North-East of Scotland, UK. Seventeen semi-structured interviews were conducted with adults aged 65 or less. Interviews were analysed using the Framework approach utilising thematic analysis. RESULTS: Almost every participant reported that they were unable to function fully as a result of the nature and unpredictability of their headaches and this had caused disruption to their work, family life and social activities. Many also reported a negative impact on mood including feeling depressed, aggressive or embarrassed. Most participants had formed their own ideas about different aspects of their headache and several had searched for, or were seeking, increased understanding of their headache from a variety of sources. Many participants reported that their headaches caused them constant worry and anguish, and they were concerned that there was a serious underlying cause. A variety of methods were being used to manage headaches including conventional medication, complementary therapies and self-developed management techniques. Problems associated with all of these management strategies emerged. CONCLUSION: Headache has wide-ranging adverse effects on individuals and is often accompanied by considerable worry. The development of new interventions or educational strategies aimed at reducing the burden of the disorder and associated anxiety are needed
Randomised controlled trial of school-based humanistic counselling for emotional distress in young people: Feasibility study and preliminary indications of efficacy
The purpose of this study was to test the feasibility of a randomised controlled trial comparing six weeks of humanistic school-based counselling versus waiting list in the reduction of emotional distress in young people, and to obtain initial indications of efficacy. Following a screening procedure, young people (13 - 15 years old) who experienced emotional distress were randomised to either humanistic counselling or waiting list in this multi-site study. Outcomes were assessed using a range of self-report mental health measures, with the emotional symptoms subscale of the Strengths and Difficulties Questionnaire (SDQ) acting as the primary outcome indicator. Recruitment procedures were successful, with 32 young people consenting to participate in the trial and 27 completing endpoint measures. Trial procedures were acceptable to all involved in the research. No significant differences were found between the counselling and waiting list groups in reductions in levels of emotional symptoms (Hedges' g = 0.03), but clients allocated to counselling showed significantly greater improvement in prosocial behaviour (g = 0.89) with an average effect size (g) across the nine outcome measures of 0.25. Participants with higher levels of depressive symptoms showed significantly greater change. This study suggested that a randomised controlled trial of counselling in schools is acceptable and feasible, although initial indications of efficacy are mixed
Young Aphids Avoid Erroneous Dropping when Evading Mammalian Herbivores by Combining Input from Two Sensory Modalities
Mammalian herbivores may incidentally ingest plant-dwelling insects while foraging. Adult pea aphids (Acyrthosiphon pisum) avoid this danger by dropping off their host plant after sensing the herbivore's warm and humid breath and the vibrations it causes while feeding. Aphid nymphs may also drop (to escape insect enemies), but because of their slow movement, have a lower chance of finding a new plant. We compared dropping rates of first-instar nymphs with those of adults, after exposing pea aphids to different combinations of simulated mammalian breath and vibrations. We hypothesized that nymphs would compensate for the greater risk they face on the ground by interpreting more conservatively the mammalian herbivore cues they perceive. Most adults dropped in response to breath alone, but nymphs rarely did so. Breath stimulus accompanied by one concurrent vibrational stimulus, caused a minor rise in adult dropping rates. Adding a second vibration during breath had no additional effect on adults. The nymphs, however, relied on a combination of the two types of stimuli, with a threefold increase in dropping rates when the breath was accompanied by one vibration, and a further doubling of dropping rates when the second vibration was added. The age-specificity of the aphids' herbivore detection mechanism is probably an adaptation to the different cost of dropping for the different age groups. Relying on a combination of stimuli from two sensory modalities enables the vulnerable nymphs to avoid costly mistakes. Our findings emphasize the importance of the direct trophic effect of mammalian herbivory for plant-dwelling insects
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