145 research outputs found
Exploring University Student’s Experiences when Using Cannabis: A Qualitative Inquiry
Cannabis use is increasing especially in younger individuals in Nova Scotia. In the university setting, there is a growing body of literature seeking to understand why individuals choose to use cannabis for management of symptoms. As one third of Nova Scotians 15 years and older report consuming cannabis it was important to understand the perspectives and experiences of university students. Young adults utilize cannabis for wide ranging symptoms, anxiety, depression, social acceptance, and pain and many are not managed by a health care professional. Therefore, we sought to understand why students choose to use cannabis. We utilized a qualitative descriptive approach to seek rich, thick descriptions. We interviewed six young adults using a semi-structured approach. University ethics were sought and granted. A letter of information and informed consent were utilized. Interviews were conducted following pandemic guidelines and utilizing an e-platform. Data was transcribed verbatim. The researchers read, re-read, and thematically analyzed the transcripts. Themes were identified following a thematic analysis process. Findings were shared with participants and presented at a university research event. The following themes emerged from the data: (1) perceived benefits of cannabis on ones’ symptoms; (2) perceived risks of cannabis use; and (3) reasons for use instead of medically prescribed medications. This small qualitative study shares the experiences of university students using cannabis to manage symptoms. Participants self-medicate their symptoms, e.g., anxiety, depression, and social and family stressors. They engage in a trial-and-error process to get the right amount of cannabis to manage symptoms. They also use cannabis to numb stressors and to feel normalized in social situations. Participants also described risks associated with cannabis use, overuse and unanticipated side-effects including risk of addiction. Finally, they choose cannabis as there continues to be stigma associated with discussing mental health issues with their physician, and it is easy to access cannabis without a prescription. More research is needed to fully understand the role of cannabis as it shifts its use and access with legalization
Exploring the Diagnostic Journey of Individuals Living with Parkinson Disease: A Qualitative Inquiry
Background: Parkinson’s Disease is a progressive neurological disorder. Criteria and guidelines have been established to improve the accuracy of diagnosis with the present accuracy of diagnosis being approximately 82%. Receiving a diagnosis of an incurable and disabling disease is a stressful life event. Accurate and timely information affects the patient’s acceptance of the disease and potential treatments. The objective of the research project was to explore the experiences of patients living with PD and to give voice to the patient’s perspectives related to their experiences while awaiting a diagnosis, which can take years. We explored experiences related to the individuals’ physical and emotional health. Methods: Ethics was sought and granted through Cape Breton University. Following informed consent, purposive and snowballing approaches were used to recruit adult participants living with PD in the community setting. Qualitative data were collected using semi-structured interviews to support five individuals to openly share their experiences. Data was typed verbatim, and a thematic analysis approach was used to compare similarities across the data. Results: Participants’ experiences related to their diagnostic journey were thematically analyzed and the following three themes emerged: 1) background of diagnosis, 2) healthcare support, and 3) challenges associated with the experience. Conclusion: The results of this study contribute to a deeper understanding of the journey and experiences of individuals diagnosed with Parkinson’s Disease. The findings emphasize the effects on an individuals’ life and the importance of receiving a clinical diagnosis
Left posterior inferior frontal gyrus is causally involved in complex sentence comprehension
INTRODUCTION Storage and reordering of words are two core processes required for successful sentence comprehension. Storage is necessary whenever the verb and its arguments (i.e., subject and object) are separated over a long distance, while reordering is necessary whenever the argument order is atypical (e.g., object-first order in German, where subject-first order is typical). Previous neuroimaging work (Meyer et al., 2012) has associated storage with the left planum temporale (PT), and reordering with the left posterior inferior frontal gyrus (pIFG). However, it is unclear whether left PT and pIFG are indeed causally relevant for storage and reordering, respectively. Here, we tested the necessity of the PT and pIFG for storage and reordering using repetitive transcranial magnetic stimulation (rTMS). METHODS We applied either effective online rTMS (5 pulses at 10 Hz) over PT or pIFG, or sham rTMS, while subjects listened to sentences that independently manipulated storage demands (short vs. long argument–verb distance) and reordering demands (subject– vs. object-first argument order). We employed behavioral modeling, using a drift diffusion model, to assess rTMS-induced disruption of sentence comprehension. RESULTS We found that rTMS over pIFG, but not PT, selectively impaired reordering during the processing of sentences with a long argument–verb distance. Specifically, relative to sham rTMS, rTMS over pIFG significantly increased the performance decline for object– vs. subject-first long-distance sentences (t23 = 2.86; p = 0.009). This effect was anatomically specific as the same comparison for PT stimulation was far from significant (t23 = −0.11; p = 0.9), and a direct across-sites comparison showed that the pIFG effect was significantly stronger (t23 = −2.62; p = 0.015). CONCLUSION Our results provide the first causal evidence that the left pIFG supports the reordering of arguments in long-distance sentences. We thereby substantially extend previous neuroimaging studies that showed a correlation between pIFG activation and reordering demands. Together with previous evidence (Lauro et al., 2010), our findings indicate that the left pIFG crucially supports the comprehension of syntactically complex sentences. These results might extend to other domains, such as music (Maess et al., 2001) and action (Clerget et al., 2009), indicating a domain-general role of left pIFG in the processing of hierarchically-structured sequences
Adaptive plasticity in the healthy reading network investigated through combined neurostimulation and neuroimaging
The reading network in the human brain comprises several regions, including the left inferior frontal cortex (IFC), ventral occipito-temporal cortex (vOTC) and dorsal temporo-parietal cortex (TPC). The left TPC is crucial for phonological decoding, i.e., for learning and retaining sound-letter mappings. Here, we tested the causal contribution of this area for reading with repetitive transcranial magnetic stimulation (rTMS) and explored the response of the reading network using functional magnetic resonance imaging (fMRI). 28 healthy adult readers overtly read simple and complex words and pseudowords during fMRI after effective or sham TMS over the left TPC. Behaviorally, effective stimulation slowed pseudoword reading. A multivariate pattern analysis showed a shift in activity patterns in the left IFC for pseudoword reading after effective relative to sham TMS. Furthermore, active TMS led to increased effective connectivity from the left vOTC to the left TPC, specifically for pseudoword processing. The observed changes in task-related activity and connectivity suggest compensatory reorganization in the reading network following TMS-induced disruption of the left TPC. Our findings provide first evidence for a causal role of the left TPC for overt pseudoword reading and emphasize the relevance of functional interactions in the healthy reading network for successful pseudoword processing
Frenkel and charge transfer excitons in C60
We have studied the low energy electronic excitations of C60 using momentum
dependent electron energy-loss spectroscopy in transmission. The momentum
dependent intensity of the gap excitation allows the first direct experimental
determination of the energy of the 1Hg excitation and thus also of the total
width of the multiplet resulting from the gap transition. In addition, we could
elucidate the nature of the following excitations - as either Frenkel or charge
transfer excitons.Comment: RevTEX, 3 Figures, to appear in Phys. Rev.
Coupled Contagion Dynamics of Fear and Disease: Mathematical and Computational Explorations
Background: In classical mathematical epidemiology, individuals do not adapt their contact behavior during epidemics. They do not endogenously engage, for example, in social distancing based on fear. Yet, adaptive behavior is welldocumented in true epidemics. We explore the effect of including such behavior in models of epidemic dynamics. Methodology/Principal Findings: Using both nonlinear dynamical systems and agent-based computation, we model two interacting contagion processes: one of disease and one of fear of the disease. Individuals can ‘‘contract’ ’ fear through contact with individuals who are infected with the disease (the sick), infected with fear only (the scared), and infected with both fear and disease (the sick and scared). Scared individuals–whether sick or not–may remove themselves from circulation with some probability, which affects the contact dynamic, and thus the disease epidemic proper. If we allow individuals to recover from fear and return to circulation, the coupled dynamics become quite rich, and can include multiple waves of infection. We also study flight as a behavioral response. Conclusions/Significance: In a spatially extended setting, even relatively small levels of fear-inspired flight can have a dramatic impact on spatio-temporal epidemic dynamics. Self-isolation and spatial flight are only two of many possible actions that fear-infected individuals may take. Our main point is that behavioral adaptation of some sort must b
Shifting the Paradigm: The Putative Mitochondrial Protein ABCB6 Resides in the Lysosomes of Cells and in the Plasma Membrane of Erythrocytes
ABCB6, a member of the adenosine triphosphate–binding cassette (ABC) transporter family, has been proposed to be responsible for the mitochondrial uptake of porphyrins. Here we show that ABCB6 is a glycoprotein present in the membrane of mature erythrocytes and in exosomes released from reticulocytes during the final steps of erythroid maturation. Consistent with its presence in exosomes, endogenous ABCB6 is localized to the endo/lysosomal compartment, and is absent from the mitochondria of cells. Knock-down studies demonstrate that ABCB6 function is not required for de novo heme biosynthesis in differentiating K562 cells, excluding this ABC transporter as a key regulator of porphyrin synthesis. We confirm the mitochondrial localization of ABCB7, ABCB8 and ABCB10, suggesting that only three ABC transporters should be classified as mitochondrial proteins. Taken together, our results challenge the current paradigm linking the expression and function of ABCB6 to mitochondria
Characterization of the Metabolic Phenotype of Rapamycin-Treated CD8+ T Cells with Augmented Ability to Generate Long-Lasting Memory Cells
Cellular metabolism plays a critical role in regulating T cell responses and the development of memory T cells with long-term protections. However, the metabolic phenotype of antigen-activated T cells that are responsible for the generation of long-lived memory cells has not been characterized.. than untreated control T cells. In contrast to that control T cells only increased glycolysis, rapamycin-treated T cells upregulated both glycolysis and oxidative phosphorylation (OXPHOS). These rapamycin-treated T cells had greater ability than control T cells to survive withdrawal of either glucose or growth factors. Inhibition of OXPHOS by oligomycin significantly reduced the ability of rapamycin-treated T cells to survive growth factor withdrawal. This effect of OXPHOS inhibition was accompanied with mitochondrial hyperpolarization and elevation of reactive oxygen species that are known to be toxic to cells.Our findings indicate that these rapamycin-treated T cells may represent a unique cell model for identifying nutrients and signals critical to regulating metabolism in both effector and memory T cells, and for the development of new methods to improve the efficacy of adoptive T cell cancer therapy
Disruption of arterial perivascular drainage of amyloid-β from the brains of mice expressing the human APOE ε4 allele
Failure of elimination of amyloid-β (Aβ) from the brain and vasculature appears to be a key factor in the etiology of sporadic Alzheimer’s disease (AD) and cerebral amyloid angiopathy (CAA). In addition to age, possession of an apolipoprotein E (APOE) ε4 allele is a strong risk factor for the development of sporadic AD. The present study tested the hypothesis that possession of the APOE ε4 allele is associated with disruption of perivascular drainage of Aβ from the brain and with changes in cerebrovascular basement membrane protein levels. Targeted replacement (TR) mice expressing the human APOE3 (TRE3) or APOE4 (TRE4) genes and wildtype mice received intracerebral injections of human Aβ40. Aβ40 aggregated in peri-arterial drainage pathways in TRE4 mice, but not in TRE3 or wildtype mice. The number of Aβ deposits was significantly higher in the hippocampi of TRE4 mice than in the TRE3 mice, at both 3- and 16-months of age, suggesting that clearance of Aβ was disrupted in the brains of TRE4 mice. Immunocytochemical and Western blot analysis of vascular basement membrane proteins demonstrated significantly raised levels of collagen IV in 3-month-old TRE4 mice compared with TRE3 and wild type mice. In 16-month-old mice, collagen IV and laminin levels were unchanged between wild type and TRE3 mice, but were lower in TRE4 mice. The results of this study suggest that APOE4 may increase the risk for AD through disruption and impedance of perivascular drainage of soluble Aβ from the brain. This effect may be mediated, in part, by changes in age-related expression of basement membrane proteins in the cerebral vasculature
Modified constraint-induced movement therapy or bimanual occupational therapy following injection of Botulinum toxin-A to improve bimanual performance in young children with hemiplegic cerebral palsy: a randomised controlled trial methods paper
<p>Abstract</p> <p>Background</p> <p>Use of Botulinum toxin-A (BoNT-A) for treatment of upper limb spasticity in children with cerebral palsy has become routine clinical practice in many paediatric treatment centres worldwide. There is now high-level evidence that upper limb BoNT-A injection, in combination with occupational therapy, improves outcomes in children with cerebral palsy at both the body function/structure and activity level domains of the International Classification of Functioning, Disability and Health. Investigation is now required to establish what amount and specific type of occupational therapy will further enhance functional outcomes and prolong the beneficial effects of BoNT-A.</p> <p>Methods/Design</p> <p>A randomised, controlled, evaluator blinded, prospective parallel-group trial. Eligible participants were children aged 18 months to 6 years, diagnosed with spastic hemiplegic cerebral palsy and who were able to demonstrate selective motor control of the affected upper limb. Both groups received upper limb injections of BoNT-A. Children were randomised to either the modified constraint-induced movement therapy group (experimental) or bimanual occupational therapy group (control). Outcome assessments were undertaken at pre-injection and 1, 3 and 6 months following injection of BoNT-A. The primary outcome measure was the Assisting Hand Assessment. Secondary outcomes included: the Quality of Upper Extremity Skills Test; Pediatric Evaluation of Disability Inventory; Canadian Occupational Performance Measure; Goal Attainment Scaling; Pediatric Motor Activity Log; modified Ashworth Scale and; the modified Tardieu Scale.</p> <p>Discussion</p> <p>The aim of this paper is to describe the methodology of a randomised controlled trial comparing the effects of modified constraint-induced movement therapy (a uni-manual therapy) versus bimanual occupational therapy (a bimanual therapy) on improving bimanual upper limb performance of children with hemiplegic cerebral palsy following upper limb injection of BoNT-A. The paper outlines the background to the study, the study hypotheses, outcome measures and trial methodology. It also provides a comprehensive description of the interventions provided.</p> <p>Trial Registration</p> <p>ACTRN12605000002684</p
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