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1.
Article En | MEDLINE | ID: mdl-38736023

UV-B radiation can substantially impact plant growth. To study UV-B effects, broadband UV-B tubes are commonly used. Apart from UV-B, such tubes also emit UV-A wavelengths. This study aimed to distinguish effects of different UV-B intensities on Arabidopsis thaliana wildtype and UVR8 mutant rosette morphology, from those by accompanying UV-A. UV-A promotes leaf-blade expansion along the proximal-distal, but not the medio-lateral, axis. Consequent increases in blade length: width ratio are associated with increased light capture. However, petiole length is not affected by UV-A exposure. This scenario is distinct from the shade avoidance driven by low red to far-red ratios, whereby leaf blade elongation is impeded but petiole elongation is promoted. Thus, the UV-A mediated elongation response is phenotypically distinct from classical shade avoidance. UV-B exerts inhibitory effects on petiole length, blade length and leaf area, and these effects are mediated by UVR8. Thus, UV-B antagonises aspects of both UV-A mediated elongation and classical shade avoidance. Indeed, this study shows that accompanying UV-A wavelengths can mask effects of UV-B. This may lead to potential underestimates of the magnitude of the UV-B induced morphological response using broadband UV-B tubes.

2.
Pediatr Dermatol ; 41(1): 5-11, 2024.
Article En | MEDLINE | ID: mdl-37906120

BACKGROUND: Dupilumab is approved for moderate-severe atopic dermatitis (AD) in patients aged ≥6 months by the US Food and Drug Administration and Health Canada; however, there are little real-world data because providers have limited practical experience with this recently approved therapy. OBJECTIVES: To describe the real-world effectiveness and safety in patients aged <12 years with moderate-severe AD currently receiving or previously having received dupilumab. METHODS: A multicenter retrospective study was conducted at six Canadian sites. Cases were divided into Group 1 ≤2 years old, Group 2 >2 to <6 years old, and Group 3 ≥6 to <12 years old. Medical history and details of dupilumab treatment were collected. The primary outcome was to measure the improvement in eczema area and severity index. Secondary outcomes examined included the children's dermatology life quality index/infant's dermatitis quality of life, peak pruritus numerical rating scale, and delay to dupilumab access for patients who were considered off-label for dupilumab due to their age. RESULTS: Sixty three pediatric patients (37 males) with moderate-to-severe AD were included; the mean age was 6.4 years old (range: 2-11) when dupilumab treatment was started. Overall, 75% (36/48) achieved EASI-75% and 71% (34/48) achieved EASI-90. EASI-75 and EASI-90 were achieved in 90% (17/19) and 73% (12/19) in patients <6 years old, and 76% (22/29) and 59% (17/29) in patients >6 years old, respectively. No serious adverse events were reported. CONCLUSIONS: Dupilumab is safe and effective for patients under the age of 12. However, even for experienced providers, access to the medication was challenging.


Antibodies, Monoclonal, Humanized , Dermatitis, Atopic , Child , Child, Preschool , Humans , Male , Canada , Dermatitis, Atopic/drug therapy , Double-Blind Method , Quality of Life , Retrospective Studies , Severity of Illness Index , Treatment Outcome , Female , Infant
3.
Photochem Photobiol Sci ; 22(9): 2189-2204, 2023 Sep.
Article En | MEDLINE | ID: mdl-37270745

Plants are continuously exposed to combinations of abiotic and biotic stressors. While much is known about responses to individual stressors, understanding of plant responses to combinations of stressors is limited. The effects of combined exposure to drought and UV radiation are particularly relevant in the context of climate change. In this study it was explored whether UV-exposure can be used as a tool to prime stress-resistance in plants grown under highly protected culture conditions. It was hypothesised that priming mint plantlets (Mentha spicata L.) with a low-dose of UV irradiance can alleviate the drought effect caused by a change in humidity upon transplanting. Plants were grown for 30 days on agar in sealed tissue culture containers. During this period, plants were exposed to ~ 0.22 W m-2 UV-B for 8 days, using either UV-blocking or UV- transmitting filters. Plants were then transplanted to soil and monitored for a further 7 days. It was found that non-UV exposed mint plants developed necrotic spots on leaves, following transfer to soil, but this was not the case for plants primed with UV. Results showed that UV induced stress resistance is associated with an increase in antioxidant capacity, as well as a decrease in leaf area. UV-induced stress resistance can be beneficial in a horticultural setting, where priming plants with UV-B can be used as a tool in the production of commercial crops.


Stress, Physiological , Ultraviolet Rays , Antioxidants , Droughts , Crops, Agricultural
4.
Biomolecules ; 12(12)2022 12 14.
Article En | MEDLINE | ID: mdl-36551307

UV-B and UV-A radiation are natural components of solar radiation that can cause plant stress, as well as induce a range of acclimatory responses mediated by photoreceptors. UV-mediated accumulation of flavonoids and glucosinolates is well documented, but much less is known about UV effects on carotenoid content. Carotenoids are involved in a range of plant physiological processes, including photoprotection of the photosynthetic machinery. UV-induced changes in carotenoid profile were quantified in plants (Arabidopsis thaliana) exposed for up to ten days to supplemental UV radiation under growth chamber conditions. UV induces specific changes in carotenoid profile, including increases in antheraxanthin, neoxanthin, violaxanthin and lutein contents in leaves. The extent of induction was dependent on exposure duration. No individual UV-B (UVR8) or UV-A (Cryptochrome or Phototropin) photoreceptor was found to mediate this induction. Remarkably, UV-induced accumulation of violaxanthin could not be linked to protection of the photosynthetic machinery from UV damage, questioning the functional relevance of this UV response. Here, it is argued that plants exploit UV radiation as a proxy for other stressors. Thus, it is speculated that the function of UV-induced alterations in carotenoid profile is not UV protection, but rather protection against other environmental stressors such as high intensity visible light that will normally accompany UV radiation.


Arabidopsis Proteins , Arabidopsis , Ultraviolet Rays/adverse effects , Arabidopsis/metabolism , Carotenoids/metabolism , Photosynthesis , Arabidopsis Proteins/metabolism , Chromosomal Proteins, Non-Histone/metabolism
6.
CMAJ ; 193(1): E37, 2021 01 04.
Article Fr | MEDLINE | ID: mdl-33397642
8.
Emerg Infect Dis ; 24(1): 165-166, 2018 01.
Article En | MEDLINE | ID: mdl-29260666

In Canada, Hansen disease (leprosy) is rare and not considered in diagnoses for nonimmigrant patients. We report Mycobacterium leprae infection in a Canadian man whose sole travel was to Florida, USA. The M. leprae isolate was identified as armadillo-associated genotype 3I-2-v1. Travelers to the southern United States should avoid contact with armadillos.


Leprosy/diagnosis , Leprosy/epidemiology , Aged , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/therapeutic use , Canada , Dapsone/administration & dosage , Dapsone/therapeutic use , Drug Therapy, Combination , Florida , Humans , Leprostatic Agents/administration & dosage , Leprostatic Agents/therapeutic use , Leprosy/microbiology , Male , Mycobacterium leprae , Ofloxacin/administration & dosage , Ofloxacin/therapeutic use , Rifampin/administration & dosage , Rifampin/therapeutic use , Travel
9.
BMC Health Serv Res ; 15: 423, 2015 Sep 28.
Article En | MEDLINE | ID: mdl-26412081

BACKGROUND: The provision of rehabilitation differs between developed and developing countries, this could impact on the outcomes of post stroke rehabilitation. The aim of this paper is to present provision of in-patient stroke rehabilitation. In addition the challenges experienced by the individuals with participation post discharge are also presented. METHODS: Qualitative and quantitative research methods were used to collect data. The quantitative data was collected using a retrospective survey of stroke patients admitted to hospitals over a three- to five-year period. Quantitative data was captured on a validated data capture sheet and analysed descriptively. The qualitative data was collected using interviews from a purposively and conveniently selected sample, audio-taped and analysed thematically. The qualitative data was presented within the participation model. RESULTS: A total of 168 medical folders were reviewed for a South African sample, 139 for a Rwandan sample and 145 for a Tanzanian sample. The mean age ranged from 62.6 (13.78) years in the South African sample to 56.0 (17.4) in the Rwandan sample. While a total of 98 % of South African stroke patients received physiotherapy, only 39.4 % of Rwandan patients received physiotherapy. From the qualitative interviews, it became clear that the stroke patients had participation restrictions. When conceptualised within the Participation Model participation restrictions experienced by the stroke patients were a lack of accomplishment, inability to engage in previous roles and a perception of having health problems. DISCUSSION: With the exception of Rwanda, stroke patients in the countries studied are admitted to settings early post stroke allowing for implementation of effective acute interventions. The participants were experiencing challenges which included a lack of transport and the physical geographic surroundings in the rural settings not being conducive to wheelchair use. CONCLUSION: Stroke patients admitted to hospitals in certain African countries could receive limited in-patient therapeutic interventions. With the exception of barriers in the physical environment, stroke patients in developing countries where resources are limited experience the same participation restrictions as their counterparts in developed countries where resources are more freely available. Rehabilitation interventions in these developing countries should therefore be community-based focussing on intervening in the physical environment.


Disabled Persons/rehabilitation , Healthcare Disparities/statistics & numerical data , Patient Discharge/economics , Physical Therapy Modalities/organization & administration , Stroke Rehabilitation , Adult , Aged , Disabled Persons/psychology , Environment Design , Female , Health Care Surveys , Healthcare Disparities/economics , Humans , Inpatients , Male , Middle Aged , Needs Assessment , Qualitative Research , Research Design , Retrospective Studies , South Africa/epidemiology , Stroke/economics
10.
Can Assoc Radiol J ; 64(3): 170-5, 2013 Aug.
Article En | MEDLINE | ID: mdl-22867960

Education in ethics is a requirement for all Royal College residency training programs as laid out in the General Standards of Accreditation for residency programs in Canada. The ethical challenges that face radiologists in clinical practice are often different from those that face other physicians, because the nature of the physician-patient interaction is unlike that of many other specialties. Ethics education for radiologists and radiology residents will benefit from the development of teaching materials and resources that focus on the issues that are specific to the specialty. This article is intended to serve as an educational resource for radiology training programs to facilitate teaching ethics to residents and also as a continuing medical education resource for practicing radiologists. In an environment of limited health care resources, radiologists are frequently asked to expedite imaging studies for patients and, in some respects, act as gatekeepers for specialty care. The issues of wait lists, queue jumping, and balancing the needs of individuals and society are explored from the perspective of a radiologist.


Ethics, Medical , Radiology/education , Radiology/ethics , Waiting Lists , Canada , Education, Medical, Continuing/ethics , Education, Medical, Continuing/methods , Humans , Internship and Residency/ethics , Internship and Residency/methods
13.
J Learn Disabil ; 39(4): 352-63, 2006.
Article En | MEDLINE | ID: mdl-16895159

Event-related potentials (ERPs) were recorded from 27 children (14 girls, 13 boys) who varied in their reading skill levels. Both behavior performance measures recorded during the ERP word classification task and the ERP responses themselves discriminated between children with above-average, average, and below-average reading skills. ERP amplitudes and peak latencies decreased as reading skills increased. Furthermore, hemisphere differences increased with higher reading skill levels. Sex differences were also related to ERP amplitude variations across the scalp. However, ERPs recorded from boys and girls did not differ as a function of differences in the children's reading levels.


Aptitude , Brain/anatomy & histology , Reading , Brain/physiology , Child , Evoked Potentials/physiology , Female , Humans , Male
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