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The COVID-19 pandemic has seen an increase in depression and anxiety among those with and without a history of mental illness. Commonly used forms of psychological therapy improve mental health by teaching psychotherapeutic strategies that assist people to better manage their symptoms and cope with life stressors. Minimal research to date has explored their application or value in managing mental health during significant broad-scale public health crises.
To determine which psychotherapeutic strategies people who have previously received therapy use to manage their distress during the COVID-19 pandemic, and whether the use and perceived helpfulness of these strategies has an effect on symptoms of depression and anxiety.
Data (N = 857) was drawn from multiple waves of a representative longitudinal study of the effects of COVID-19 on the mental health of Australian adults, which includes measures of anxiety, depression and experiences with psychotherapy and psychotherapeutic strategies.
Previous engagement in therapy with psychotherapeutic strategies had a protective effect on depressive but not anxiety symptoms. Common and helpful strategies used by respondents were exercise, mindfulness and breathing exercises. Using mindfulness and perceiving it to be helpful was associated with lower levels of depression and anxiety symptoms. No other strategies were associated with improved mental health.
Prior knowledge of psychotherapeutic strategies may play a role in managing mental health during unprecedented public health events such as a global pandemic. There may be value in promoting these techniques more widely in the community to manage general distress during such times.
Three holes were drilled to the bed of Rutford Ice Stream, through ice up to 2154 m thick, to investigate the basal processes and conditions associated with fast ice flow and the glacial history of the West Antarctic Ice Sheet. A narrative of the drilling, measuring and sampling activities, as well as some preliminary results and initial interpretations of subglacial conditions, is given. These were the deepest subglacial access holes ever drilled using the hot-water drilling method. Samples of bed and englacial sediments were recovered, and a number of instruments were installed in the ice column and the bed. The ice–bed interface was found to be unfrozen, with an existing, well-developed subglacial hydrological system at high pressure, within ~1% of the ice overburden. The bed itself comprises soft, water-saturated sediments, consistent with previous geophysical interpretations. Englacial sediment quantity varies significantly between two locations ~2 km apart, and possibly over even shorter (~20 m) distances. Difficulties and unusual observations encountered while connecting to the subglacial hydrological system in one hole possibly resulted from the presence of a large clast embedded in the bottom of the ice.
Parasites sometimes expand their host range and cause new disease aetiologies. Genetic changes can then occur due to host-specific adaptive alterations, particularly when parasites cross between evolutionarily distant hosts. Characterizing genetic variation in Cryptosporidium from humans and other animals may have important implications for understanding disease dynamics and transmission. We analyse sequences from four loci (gp60, HSP-70, COWP and actin) representing multiple Cryptosporidium species reported in humans. We predicted low genetic diversity in species that present unusual human infections due to founder events and bottlenecks. High genetic diversity was observed in isolates from humans of Cryptosporidium meleagridis, Cryptosporidium cuniculus, Cryptosporidium hominis and Cryptosporidium parvum. A deviation of expected values of neutrality using Tajima's D was observed in C. cuniculus and C. meleagridis. The high genetic diversity in C. meleagridis and C. cuniculus did not match our expectations but deviations from neutrality indicate a recent decrease in genetic variability through a population bottleneck after an expansion event. Cryptosporidium hominis was also found with a significant Tajima's D positive value likely caused by recent population expansion of unusual genotypes in humans. These insights indicate that changes in genetic diversity can help us to understand host-parasite adaptation and evolution.
The Memorandum of Understanding (MoU) concluded between the UK and Ireland in May 2019 provides one of the few clear legacies of Theresa May’s premiership. The Common Travel Area (CTA) between Ireland, the UK, the Channel Islands, and the Isle of Man provides the basis for domestic immigration and nationality laws which permit Irish citizens to reside in the UK and for them to be treated as “not foreign” in the context of UK domestic laws concerning access to healthcare, employment, social security, political participation, and education. Yet it has long lacked legal definition. The UK and Ireland reciprocate, to a rough extent, these rights for each other’s citizens. The MoU and related developments mark the first steps towards clarifying the CTA’s scope. The rush to conclude this MoU and alter parts of both countries’ domestic law relating to the CTA nonetheless illustrate the fragile state of Ireland–UK relations with Brexit looming. This Article explores whether these reforms will enable people who rely upon the CTA as a foundation of life outside their home country to protect their interests through litigation, and reflects upon the relationship between these arrangements and the protections for EU citizens proposed under the UK–EU Withdrawal Agreement.
Tuberculosis (TB) in children is a critical public health issue. In Bohol, Philippines, we found a high tuberculin skin test (TST)-positive prevalence (weighted prevalence = 6.4%) among 5476 children (<15 years) from 184 villages, with geographically isolated communities having prevalence as high as 29%. Therefore, we conducted a geospatial and hot spot analysis to examine the association between villages with high TST-positive prevalence (⩾6.5%) and access to medical care (distance (in kilometres and minutes of travel time) to the municipal Rural Health Units (RHU)), access to healthcare resources (distance to Provincial Health Office (PHO)) and socioeconomic determinants of health. Hot spot analysis revealed significant clusters of TST-positive prevalence in villages farthest from the PHO. Based on univariate analysis, the following variables associated with high prevalence were included in the multivariate model: minutes of travel time to the PHO, distance to the PHO, island villages and total deprivation based on socioeconomic indicators. In the final model, only distance to PHO in minutes was significant (P = 0.005). When evaluated further, greater than 1-hour drive significantly increased risk for TST-positivity (P = 0.003). Distance to healthcare resources likely increases the risk of TB transmission within the community. Expanding TB control efforts to geographically isolated areas is critical.
Altered neurocognitive function in schizophrenia could reflect both genetic and illness-specific effects.
To use functional magnetic resonance imaging to discriminate between the influences of the genetic risk for schizophrenia and environmental factors on the neural substrate of verbal fluency, a candidate schizophrenia endophenotype using a case control twin design.
We studied 23 monozygotic twin pairs: 13 pairs discordant for schizophrenia and 10 pairs of healthy volunteer twins. Groups were matched for age, gender, handedness, level of education, parental socio-economic status, and ethnicity. Behavioural performance and regional brain activation during a phonological verbal fluency task were assessed.
Relative to healthy control twins, both patients and their non-psychotic co-twins produced fewer correct responses and showed less activation in the medial temporal region and inferior frontal gyrus. Twins with schizophrenia showed greater activation than both their non-psychotic co-twins and controls in right lateral temporal cortex, reflecting reduced deactivation during word generation while their non-psychotic co-twins showed greater activation in the left temporal cortex.
Both genetic vulnerability to schizophrenia and schizophrenia were associated with impaired verbal fluency performance, reduced engagement of the medial temporal region and dorsal inferior frontal gyrus. Schizophrenia was specifically associated with an additional reduction in deactivation in the right temporal cortex.
Alterations in gray matter volume (GMV) are a robust feature of schizophrenia. However, it is not clear to what extent these abnormalities are correlates of the genetic liability to the disorder, as opposed to environmental factors and the disorder itself.
We investigated the influence of genetic risk and illness on GMV in monozygotic (MZ) twin pairs concordant and discordant for schizophrenia.
Total and regional GMVs were measured from magnetic resonance images of 80 twins: 14 MZ pairs concordant for schizophrenia, 9 pairs discordant for schizophrenia, and 17 healthy MZ twin pairs. The three groups were matched for age, gender, handedness, level of education, parental socioeconomic status, and ethnicity.
Total GMV was smaller in twins with schizophrenia (t=-3.17, p= 0.003) and non-psychotic co-twins from discordant pairs (t=-2.66, p= 0.011) than in healthy control twins. Twin pairs concordant for schizophrenia displayed reduced regional GMV in the inferior frontal, medial frontal, and anterior cingulate gyri, the caudate, lingual gyrus and cerebellum relative to healthy twins (p< 0.05, corrected). Within discordant pairs, twins with schizophrenia had less GMV than their non-psychotic co-twins in the insula, superior/medial frontal, pre/postcentral, cingulate and superior temporal gyri, and the paracentral lobule. There were no significant differences in regional GMV between non-psychotic co-twins and healthy controls.
The presence of schizophrenia was specifically related to reduced GMV in frontal, insular, cingulate, medial parietal and temporal cortex, over and above effects of genetic risk for the disorder.
Recent studies have identified DAAO as a probable susceptibility gene for schizophrenia and bipolar disorder. However, little is known about how this gene may affect brain function to increase vulnerability to these disorders.
The present investigation examined the impact of DAAO genotype on brain function in patients with schizophrenia, patients with bipolar I disorder and healthy volunteers.
We tested the hypotheses that the high-risk variant of DAAO would be associated with altered prefrontal function and functional connectivity in schizophrenic and bipolar patients.
We used functional magnetic resonance imaging to measure brain responses during a verbal fluency task in a total of 121 subjects comprising 40 patients with schizophrenia, 33 patients with bipolar I disorder and 48 healthy volunteers. We then used statistical parametric mapping (SPM) and psycho-physiological interaction (PPI) analyses to estimate the main effects of diagnostic group, the main effect of genotype and their interaction on brain activation and functional connectivity.
In schizophrenic patients relative to bipolar patients and controls, the high-risk variant of DAAO was associated with lower deactivation in the left precuneus and greater activation in the right calcarine and posterior cingulate gyrus during task performance. In addiction, these areas expressed altered functional connectivity with the rest of the brain in schizophrenic patients relative to bipolar patients and controls.
Our results suggest that genetic variation in DAAO has a significant impact on brain function and provide preliminary evidence for a disease-specific pattern of gene action in specific brain regions.
It has long been known that cannabis can elicit an acute psychotic reaction. Recent work shows that, of the 60 cannabinoid molecules in the plant, delta-9-tetrahydrocannibinol is responsible for the central effects of cannabis. Here we aimed to investigate, in more detail, the psychological effects of synthetic intravenous THC in healthy subjects. Over 2 experimental sessions, participants (N=22) were administered 2.5mg IV THC or placebo under randomised, double-blind conditions. Psychological reactions were assessed using standard rating instruments and a battery of cognitive tests was completed.
Following THC, there was a significant increase in self-rated and observer-rated positive psychotic symptoms which were highly correlated (r=0.62, p=0.001).Phenomena centered on de-synchronisation of self-agency (ipseity disturbance) and hypersalience/paranoia. Participants also reported a significant increase in negative symptomatology under THC conditions, which was not explained by sedation. Finally, working memory/executive functioning was markedly and consistently impaired by THC.
Here we provide further evidence that THC can elicit an acute psychotic reaction in a proportion of healthy subjects. Acute THC-psychosis elicits positive, negative and cognitive symptoms. Compared with other drug models THC recreates symptomatology across 3 major dimensions of schizophrenic psychosis without sedation/clouding of consciousness. Here we also present preliminary evidence that the molecule cannabidiol (CBD) inhibits THC-elicited positive symptoms. Current work in our laboratory is exploring the underlying mechanisms.
Epidemiological studies have reported that the increased risk of developing psychosis in cannabis users is dose related. In addition, experimental research has shown that the active constituent of cannabis responsible for its psychotogenic effect is Delta-9-Tetrahydrocannabinol (THC) (Murray et al, 2007). Recent evidence has suggested an increased in potency (% TCH) in the cannabis seized in the UK (Potter et al, 2007).
We predicted that first episode psychosis patients are more likely to use higher potency cannabis and more frequently than controls.
We collected information concerning socio-demographic, clinical characteristics and cannabis use (age at first use, frequency, length of use, type of cannabis used) from a sample of 191 first-episode psychosis patients and 120 matched healthy volunteers. All were recruited as part of the Genetic and Psychosis (GAP) study which studied all patients who presented to the South London and Maudsley Trust.
There was no significant difference in the life-time prevalence of cannabis use or age at first use between cases and controls. However, cases were more likely to be regular users (p=0.05), to be current users (p=0.04) and to have smoked cannabis for longer (p=0.01). Among cannabis users, 86.8% of 1st Episode Psychosis Patients preferentially used Skunk/Sinsemilla compared to 27.7% of Controls. Only 13.2 % of 1st Episode psychosis Patients chose to use Resin/Hash compared to 76.3% of controls. The concentration of TCH in these in South East London, ranges between 8.5 and 14 % (Potter et al, 2007). Controls (47%) were more likely to use Hash (Resin) whose average TCH concentration is 3.4% (Potter et al, 2007).
Patients with first episode psychosis have smoked higher potency cannabis, for longer and with greater frequency, than healthy controls.