The establishment of a fibroblastic cell line from yellow perch (Perca flavescens) and its potential applications in toxicology

This thesis describes the establishment, characterization and potential toxicological applications of YPF5, a yellow perch cell line. YPF5 is a fibroblastic cell line derived from the caudal fin of yellow perch. This cell line has been maintained for over 2 years. Cultures have been passaged over 60 times, and successfully cryopreserved and thawed. YPF5 is grown at room temperature in Leibovitz-15 (L-15) media, supplemented with 10% fetal bovine serum and 3% penicillin-streptomycin. The origin of YPF5 has been confirmed as Perca flavescens through “DNA Barcoding” and reaffirmed through Karyotyping (2n = 48) as per literature reported karyology for percidae including the yellow perch. YPF5 tested positive for alkaline phosphatase and negative for beta-galactosidase, markers of stem cell-like characteristics and senescence, respectively, providing evidence for a continuous cell line. Immunofluorescence staining with mesodermal cell markers (vimentin and collagen type 1) also confirmed the fibroblastic origin of the cells. In agreement with related literature, the morphological response of YPF5 exposed to cortisol made cells more epithelial-like, and exposure to ascorbic acid induced extracellular collagen secretion. YPF5 responded to different contaminants (naphthenic acid, copper sulphate, ammonium chloride and OSPW samples) in a dose dependent manner. Evaluation of possible remediation methods using bentonite and UV radiation to ameliorate toxicity of oil sands chemicals showed promise in vitro with YPF5 cells and could be investigated further

How linear features alter predator movement and the functional\ud response

In areas of oil and gas exploration, seismic lines have been reported to alter the movement patterns of wolves (Canis lupus). We developed a mechanistic first passage time model, based on an anisotropic elliptic partial differential equation, and used this to explore how wolf movement responses to seismic lines influence the encounter rate of the wolves with their prey. The model was parametrized using 5 min GPS location data. These data showed that wolves travelled faster on seismic lines and had a higher probability of staying on a seismic line once they were on it. We simulated wolf movement on a range of seismic line densities and drew implications for the rate of predator–prey interactions as described by the functional response. The functional response exhibited a more than linear increase with respect to prey density (type III) as well as interactions with seismic line density. Encounter rates were significantly higher in landscapes with high seismic line density and were most pronounced at low prey densities. This suggests that prey at low population densities are at higher risk in environments with a high seismic line density unless they learn to avoid them

The Epidemiology of Stargardt Disease in the United Kingdom

The authors thank the British Ophthalmological Surveillance Unit (BOSU) for the support received, as well as Mr Barnaby Foot, research coordinator for BOSU, for his help and advice on this project. The authors thank the following ophthalmologists who assisted with data collection for this study: N. Acharya, S. Anwar, V. Bansal, P.N. Bishop, D. Byles, J.S. Chawla, A. Churchill, M. Clarke, B. Dhillon, M. Ekstein, S. George, J. Gillian, J.T. Gillow, D. Gilmour, R. Gray, P.T.S. Gregory, R. Gupta, S.P. Kelly, I.C. Lloyd, A. Lotery, M. McKibbin, R. MacLaren, G. Menon, A.T. Moore, A. Mulvihill, Y. Osoba, R. Pilling, H. Porooshani, A. Raghu Ram, T. Rimmer, I. Russell-Eggitt, M. Sarhan, R. Savides, S. Shafquat, A. Smith, A. Tekriwal, P. Tesha, P. Watts.Peer reviewedPublisher PD

Impact of exercise-induced bronchoconstriction on athletic performance and airway health in rugby union players

Background: There is emerging evidence that the prevalence of exercise-induced bronchospasm (EIB) is significantly under-reported in many sports. There is little known about the potential performance improvement that may exist when sports players are detected and treated for EIB. Methods: Professional rugby union players with no previous history of asthma volunteered to participate in the study. Each player performed the rugby football union (RFU) fitness test and completed a eucapnic voluntary hyperpnoea (EVH) challenge at baseline and 12 weeks later. A player with a positive EVH result was prescribed beclomethasone inhaler (200 µg; two puffs per day) for 12 weeks. Players with a negative EVH test were randomly allocated to either a placebo inhaler group or acted as controls. Results: Twenty-nine rugby union players (mean ± SD; age 22.1 ± 4.2 years; body mass 100.1 ± 6.9 kg; height 1.84 ± 0.07 m) were recruited. Seven players (24% of total) had a positive EVH challenge with a mean decrease in FEV1 of -13.6 ±3.5 % from baseline. There was no significant group difference (P=0.359)in performance improvement of the RFU fitness test between the EVH positive group (mean ?: -22.3 seconds; 8.0 ± 2.8% improvement), placebo group (mean ?: -16.5 seconds; 6.7 ± 1.6% improvement), and controls (mean ?: -12.2 seconds; 5.7 ± 3.5% improvement). Conclusion: Prevalence of EIB in professional rugby union players was 24%. A 12-week prescription of beclomethasone (200 µg) showed similar improvements in RFU fitness test performance in players diagnosed with EIB compared to players with healthy airway responsiveness

Culture of airway epithelial cells from neonates sampled within 48-hours of birth

Peer reviewedPublisher PD

Stemming and best practice in the mining industry : a literature review

In 2015, after amendments to the explosives regulations, stemming became a mandatory activity for all South African mining operations. There are, however, circumstances in which it is thought stemming has an adverse impact on the blasting outcome. Some of these circumstances include blasting in hot holes, in reactive ground, or when blasting a pre-split. In order to determine when stemming is necessary, its role in the control of adverse blasting phenomena and impact on explosive performance were reviewed. Stemming was found to play a significant role in the fragmentation process and burden movement. Additionally, stemming significantly influences the control of flyrock, air-blast, and toxic fume generation. The review of the literature indicates some motivation for not using stemming for presplit, trim, hot hole, and reactive ground blasting, provided the benefits associated with not stemming the holes outweigh the risks of stemming them. Best practice for stemming from the literature indicates a stemming length of 0.7 × burden is best for larger hole diameters, and 20 to 30 × Ø for smaller hole diameters. Crushed aggregate appears to be the most effective stemming material. The South African explosives regulations pertaining to stemming were found to be consistent with those of Australia and the USA.http://www.saimm.co.za/journal-papersam2022Mining Engineerin

What do older people learn from young people? : Intergenerational learning in ‘day centre’ community settings in Malta

This study analyses what motivates older people to attend ‘day centres’ in Malta and what they believe that they derive from young people who carry out their placements at these day ‘centres’ These young people, who are aged 16–17, attend a vocational college in Malta and are studying health and social care. The study is based on a qualitative approach and employs the usage of focus groups. The main findings are that the elderly see the students as helping them on an emotional level by giving them encouragement, and on a practical level, by offering them insights that help them in modern-day life