• The effect of imagery modality on golf putting performance

      Smith, Dave; Holmes, Paul; University College Chester ; Manchester Metropolitan University (North American Society for the Psychology of Sport and Physical Activity, 2004-09)
      This study examined the effect of various imagery modalities on golf putting performance. Forty experienced male golfers were randomly assigned to one of four groups. A “written script” group received a personalized, response proposition-laden script. Participants in the audio and video groups either listened to an audiotape or watched an internal-perspective videotape of themselves putting. Control participants spent an equivalent amount of time reading golf literature. Each participant completed a 15-ball putting task twice a week for 6 weeks and also performed his imagery or reading daily during this period. Pretests revealed no significant differences in performance. Posttests, however, showed that the video and audio groups performed significantly better than the written script and control groups. This indicates that the form in which an imagery intervention is delivered can have a significant impact on its performance effectiveness
    • Effect of Methotrexate and Tea Polyphenols on the Viability and Oxidative Stress in MDA-MB-231 Breast Cancer Cells

      Owusu-Apenten, Richard K.; Kelly, Theresa; University of Ulster (SCIENCEDOMAIN International, 2015-03-24)
      Aim: To determine the effect of tea polyphenols and methotrexate on viability and reactive oxygen species (ROS) in a naturally resistant breast cancer cell line MDA-MB-231. Methodology: MDA-MB-231 cells were selected as a model for methotrexate resistant breast cancer. Drug tests were performed over 72 hours at concentrations 0-100 µM. Pre-treatments were with quercetin (QE) or epigallocatechin gallate (EGCG) for 5 hours followed by methotrexate. Cytotoxicity was measured using the MTT assay or resazurin fluorescence assay. ROS was determined using the 2’, 7’-dichlorofluorescein diacetate assay. Intracellular GSH was measured using the monochlorobimane assay. Results: Methotrexate was cytotoxic to MDA-MB-231 cells with IC50 of 35±4 µM. The IC50 value was 68±9.4 µM with QE and 83±16 µM for EGCG. The pre-treatment with QE and EGCG lowered the IC50 for methotrexate by 28% (P =0.009) and 16% (P=0.2027). Intracellular ROS concentrations increased after treatment with methotrexate, QE or EGCG singly and ROS decreased with combination treatment compared with the response for methotrexate only. There were no significant changes in intracellular GSH. Conclusion: Pretreatment with tea polyphenols partially sensitized breast cancer cells towards methotrexate and decreases intracellular ROS. More research is needed to optimize the sensitizing effect of tea phenols on the breast cancer cell response to methotrexate.
    • Effect of pH on the Radical Quenching Capacity of Tea Infusions Using the ABTS•+ Assay

      Chan, Yuk Man; Cheng, Nga Kwan; Nigam, Poonam S.; Owusu-Apenten, Richard K.; University of Chester, University of Ulster (Sciencedomain International, 2016-06-22)
      Aims: The aims of this study were to assess the impact of pH on the free radical quenching activity of tea infusions using a modified 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assay and three antioxidant compounds as reference. Study Design: In-vitro method. Place and Duration of Study: Faculty of Life and Health Science, School of Biomedical Sciences, Ulster University, UK. From Sept 2014 and May 2016. Methodology: Free radical quenching capacity of tea (Earl grey, black tea, Ceylon tea, & green tea) infusions were investigated using persulfate activated ABTS with acetate buffer (pH 4.5) or phosphate buffer saline (pH 7.0) as solvent. Tests were performed using 96-well microplates, 20 µl of sample and 280 µl of ABTS reagent, and calibrated using ascorbic acid, trolox or gallic acid as reference antioxidants. Results: Gallic acid free radical quenching was pH dependent and unsuitable as reference. The free radical quenching capacity of trolox and ascorbic acid was not significantly different at pH 4.5 and pH 7.0. The radical quenching capacity of tea infusions expressed as Trolox Equivalent Antioxidant Capacity (TEAC) or Ascorbic Acid Equivalent Antioxidant Capacity (AAEAC) was greater by 50-300% at pH 7 compared to pH 4.5. Conclusion: The modified ABTS assay is suitable for examining the influence of pH on free radical quenching ability of tea samples. Gallic acid was not a suitable reference compound. The radical quenching capacity of tea infusions increases with rising pH.
    • The effect of rainfall upon the behaviour and use of under-road culverts in four amphibian species

      Gleeson, Timothy; Petrovan, Silviu; Muir, Anna P.; University of Chester (Oxford Academic, 2019-04-29)
      Habitat fragmentation and road mortalities are major contributors towards declines in amphibian populations. This has seen the introduction of culverts, passages that run under roads and provide safe passage for amphibians. Research investigating the effects of rainfall upon amphibian culvert use is limited. This study, conducted at Frankfield Loch in Glasgow, assesses how time elapsed since rainfall influences migration behaviour and the use of culverts across four different species; common toads (Bufo bufo), common frogs (Rana temporaria and newts, a group composed of smooth newts (Lissotriton vulgaris) and palmate newts (Lissotriton helveticus). Analysis of images taken by a custom made, time lapse camera found that significantly fewer common toads (r = 0.148, n = 468, p = 0.001) and common frogs (r = −0.175, n = 106, p = 0.037) used the culvert as time since rainfall increased. This may have been caused by the culvert not maintaining wet enough conditions for amphi- bians. The study also found that more newts (r = 0.272, n = 92, p = 0.004) and common toads (r = 0.531, n = 19, p = 0.010) were using the culvert to move away from Frankfield Loch as time since rainfall increased. An increase in juvenile newts was also observed as time since rainfall increased (r = 0.214, n = 92, p = 0.020). This may have been caused by a decrease in baro- metric pressure, which follows a decrease in rainfall, acting as a cue for migration and juvenile dispersal. The study recom- mends careful consideration of the design of each culvert, incorporating species-specific preferences and the requirements of juveniles. The study also suggests that where possible the culvert should be designed to hold water for longer.
    • The effects of a carbohydrate-protein beverage on muscle function and performance following simulated multiple-sprint sport activity

      Highton, Jamie M.; Nicholas, Ceri; Twist, Craig; Lamb, Kevin L.; University of Chester (2010-09)
    • The effects of a cycling warm-up including high-intensity heavy-resistance conditioning contractions on subsequent 4 km time trial performance

      Chorley, Alan; Lamb, Kevin L.; University of Chester (National Strength and Conditioning Association, 2017-03-25)
      Prior exercise has been shown to improve subsequent performance via different mechanisms. Sport-specific conditioning contractions can be used to exploit the 'post-activation potentiation' (PAP) phenomenon to enhance performance although this has rarely been investigated in short endurance events. The aim of this study was to compare a cycling warm-up with PAP-inducing conditioning contractions (CW) with a moderate intensity warm-up (MW) on performance and physiological outcomes of 4 km time trial. Ten well-trained male endurance cyclists (V[Combining Dot Above]O2max 65.3 +/- 5.6 ml[middle dot]kg-1[middle dot]min-1) performed two 4 km cycling time trials following a 5-minute recovery after a warm-up at 60% of V[Combining Dot Above]O2max for 6.5-minutes (MW), and a warm-up with conditioning contractions (CW) consisting of 5 minutes at 60% of V[Combining Dot Above]O2max then 3 x 10-seconds at 70% of peak power interspersed with 30-seconds recovery. Blood lactate concentrations were measured before and after time trial. Expired gases were analysed along with time, power output (PO), and peak forces over each 500 m split. Following CW, mean completion time was reduced (1.7 +/- 3.5 s p > 0.05), PO increased (5.1 +/- 10.5 W p > 0.05) as did peak force per pedal stroke (5.7 +/- 11 N p > 0.05) when compared to MW. V[Combining Dot Above]O2 increased (1.4 +/- 1.6 ml[middle dot]kg-1[middle dot]min-1 p < 0.05) following CW, whilst RER decreased (0.05 +/- 0.02 p < 0.05). Physiological and performance differences following CW were greatest over the first 1500 m of the trials. The results suggest a PAP-inducing warm-up alters V[Combining Dot Above]O2 kinetics and can lead to performance improvements in short endurance cycling but work and recovery durations should be optimised for each athlete.
    • Effects of a four-week touch rugby and self-paced interval running intervention on health markers in active young men.

      Dobbin, Nick; Bloyce, Daniel; Hughes, Stephen; Twist, Craig (Springer, 2020-03-29)
      Background: Modified team sport activity has been proposed as effective exercise modality for promoting markers of health that are comparable or greater than continuous forms of activity. However, research using modified team sports is currently limited to sedentary populations using 2-3 sessions across a minimum of 8 weeks. Aim: To investigate the effects of a four-week touch rugby and self-paced interval running intervention on a range of health markers in active men. Methods: Sixteen participants (age 26.4 ± 6.4 years) were matched for age, demographic and physical activity before completing a single touch rugby (n = 8) or running (n = 8) session per week for four weeks. Measures of systolic and diastolic blood pressure, resting heart rate (RHR), body composition and biochemical status were recorded pre- and post-intervention. Results: ANCOVA analysis revealed between-group differences for impedance (P = 0.027), fat mass (P = 0.008), percentage body fat (P = 0.008) and fat free mass (P = 0.002), with greater changes after touch rugby. Systolic blood pressure decreased for both groups with greater reductions observed after touch rugby (P = 0.002). No between-group difference was observed for RHR, interleukin-6 or C-reactive protein (P > 0.05). Contrasting internal, external and perceptual loads were observed. Conclusion: The results of this study suggest that a single session of touch rugby over a 4-week period elicited greater improvements in body composition and SBP that self-paced running, with both equally beneficial for improving RHR, diastolic blood pressure and improved inflammatory status in active young men.
    • The effects of a high carbohydrate diet on cortisol and salivary immunoglobulin A (s-IgA) during a period of increase exercise workload amongst Olympic and ironman triathletes

      Costa, Ricardo J. S.; Jones, G. E.; Coleman, Robert C.; Lamb, Kevin L.; Williams, John H. H. (Georg Thieme Verlag, 2005-04-11)
      This article discusses a study of the effects of a 6-day high carbohydrate (H-CHO) diet on salivary cortisol and IgA during a period of increased exercise workload with thirty-two competitively trained male triathletes.
    • Effects of ascorbic acid, dehydroascorbic acid and methotrexate on breast cancer cell viability.

      Dosunmu, Yewande; Owusu-Apenten, Richard K.; University of Chester, University of Ulster (Sciencedomain international, 2017-10-28)
      Aims: To examine the effects of ascorbic acid (AA), dehydroascorbic acid (DHA) and methotrexate (MTX) combined treatments on (MDA-MB-231) breast cancer cell viability and intracellular reactive oxygen species (ROS). Study Design: In-vitro method. Place and Duration of Study: Biomedical Sciences Research Institute, University of Ulster, Coleraine, BT52 1SA, United Kingdom. September 2016-2017 Methodology: Cytotoxicity tests were performed with MTX (0.01- 1000 µmol/l) alone or in combination with AA or DHA, for 72 h. Cell viability was measured by 3-4,5 dimethylthiazol-2,5 diphenyl tetrazolium bromide (MTT) or Sulforhodamine B (SRB) assays. Intracellular ROS was measured by 2’,7’-dichlorofluroscein diacetate assay. Results: Treatments of MDA-MB231 cells with single agents, showed dose dependent response with 50% inhibition of cell viability (IC50) of 110.5-201.4 µmol/l (MTX), 2237-5703 µmol/l (AA) or 2474 µmol/l (DHA). Combination studies showed clear synergisms for MTX (~10 µmol/l) and DHA or AA (1100 µmol/l) but weak or no interactions at other concentrations. Three days combination treatment of DHA showed decrease of ROS, which was reversed by MTX (>10 µmol/l). Conclusions: Co-treatment of methotrexate with AA or DHA showed synergism (C1<1.0) and enhanced cytotoxicity of the anti-folate towards MDA-MB-231 breast cancer cells. Intracellular ROS decreased with AA and DHA treatment, which might be useful for reducing MTX-related oxidative stress.
    • The effects of Bodymax high-repetition resistance training on measures of body composition and muscular strength in active adult women

      O'Connor, Tracey E.; Lamb, Kevin L.; Chester College of Higher Education (National Strength and Conditioning Association, 2003-08)
      The purpose of this study was to investigate the effects of a light, high-repetition resistance-training program on skinfold thicknesses and muscular strength in women. Thirty-nine active women (mean age 38.64 +/- 4.97 years) were randomly placed into a resistance-training group (RT; n = 20) or a control group (CG; n = 19). The RT group performed a resistance-training program called Bodymax for 1 hour, 3 d.wk(-1), which incorporated the use of variable free weights and high repetitions in a group setting. The CG group continued its customary aerobic training for 1 hour 3 d.wk(-1). Five skinfold and 7 muscular strength measures were determined pretraining and after 12 weeks of training. Sum of skinfolds decreased (-17 mm; p < 0.004) and muscular strength increased (+57.4 kg; p < 0.004) in the RT group. Effect sizes for individual skinfold sites and strength measures were "medium" and "high," respectively. Bodymax is an effective resistance-training program for reducing skinfold thickness and increasing muscular strength in active women. Therefore, women with a similar or lower-activity status should consider incorporating such training into their regular fitness programs.
    • Effects of dissociated glucocorticoids on OPG and RANKL in osteoblastic cells

      Humphrey, E. L.; Williams, John H. H.; Davie, Michael W. J.; Marshall, Michael J.; Charles Salt Centre, Robert Jones and Agnes Hunt Orthopaedic Hospital, Oswestry ; University College Chester ; Charles Salt Centre, Robert Jones and Agnes Hunt Orthopaedic Hospital, Oswestry ; Charles Salt Centre, Robert Jones and Agnes Hunt Orthopaedic Hospital, Oswestry (Elsevier, 2006-05)
      This article demonstrates that dexamethasone, prednisolone, deflazacort and the dissociated glucocorticoids, RU24858, RU40066, RU24782, AL438-F1 and ZK216348 significantly inhibit osteoprotegerin (OPG) production in two human osteoblastic cell lines (MG63 and hFOB).
    • The effects of exercise-induced muscle damage on endurance performance

      Twist, Craig; Lamb, Kevin L.; Nicholas, Ceri; Burt, Dean G. (University of Chester, 2013)
      It is well documented that engaging in resistance exercise can lead to further improvements in endurance performance. Whilst, not fully understood, it is speculated that increased motor unit recruitment, improved muscle coordination and enhanced utilisation of stored elastic energy after resistance-based exercise improves exercise economy. Nevertheless, while prolonged exposure to resistance training improves endurance performance in the long-term, a consequence of such training when unaccustomed is the appearance of exercise-induced muscle damage (EIMD). Exercise-induced muscle damage is well known to affect athletic performance requiring muscular strength and power; however, its effects on markers of endurance exercise are unclear. Therefore, the aim of this thesis was to investigate the effects of EIMD on endurance performance, with an emphasis on the physiological (oxygen uptake; , minute ventilation; ), metabolic (blood lactate; [La]), perceptual (rating of perceived exertion; RPE) and kinematic (stride length; SL, stride frequency; SF) responses during sub-maximal endurance exercise.
    • The effects of exercise-induced muscle damage on maximal intensity intermittent exercise performance

      Twist, Craig; Eston, Roger; University College Chester ; University of Exeter (Spring-Verlag, 2009-05-18)
      Exercise-induced muscle damage (EIMD) is a common occurrence following activities with a high eccentric component. Alterations to the torque-velocity relationship following EIMD would appear to have serious implications for athletic performance, particularly as they relate to impairment of maximal intensity exercise. However, this has been studied infrequently. The purpose of this study was to assess the effects of EIMD on maximal intermittent sprint performance. Ten male participants (age 22.4±3.2 years, height 178.6±5.2 cm, mass 80.6±10.7 kg) performed 10×6 s cycle ergometer sprints, interspersed with 24 s recovery against a load corresponding to 0.10 kp/kg and 10×10 m sprints from a standing start, each with 12 s active (walking) recovery. All variables were measured immediately before and at 30 min, 24, 48 and 72 h following a plyometric exercise protocol comprising of 10×10 maximal counter movement jumps. Repeated measures ANOVA showed significant changes over time (all P<0.05) for perceived soreness, plasma creatine kinase activity (CK), peak power output (PPO), sprint time and rate of fatigue. Soreness was significantly higher (P<0.01) than baseline values at all time intervals (3.1, 4.9, 5.5 and 3.2 at 30 min, 24, 48 and 72 h, respectively). CK was significantly elevated (P<0.05) at 24 h (239 IU/l) and 48 h (245 IU/l) compared to baseline (151 IU/l). PPO was significantly lower (P<0.05) than baseline (1,054 W) at all time intervals (888, 946, 852 and 895 W, at 30 min, 24, 48 and 72 h, respectively). The rate of fatigue over the ten cycling sprints was reduced compared to baseline, with the greatest reduction of 48% occurring at 48 h (P<0.01). This was largely attributed to the lower PPO in the initial repetitions, resulting in a lower starting point for the rate of fatigue. Values returned to normal at 72 h. Sprint times over 10 m were higher (P<0.05) at 30 min, 24 h and 48 h compared to baseline (1.96 s) with values corresponding to 2.01, 2.02 and 2.01 at 30 min, 24 h and 48 h, respectively. Values returned to baseline by 72 h. The results provide further evidence that, following a plyometric, muscle-damaging exercise protocol, the ability of the muscle to generate power is reduced for at least 3 days. This is also manifested by a small, but statistically significant reduction in very short-term (?2 s) intermittent sprint running performance. These findings have implications for appropriate training strategies in multiple sprint sports.
    • Effects of exercise-induced muscle damage on resting metabolic rate, sub-maximal running and post-exercise oxygen consumption

      Burt, Dean G.; Lamb, Kevin L.; Nicholas, Ceri; Twist, Craig; Staffordshire University; University of Chester (Taylor & Francis, 2013-04-08)
      Exercise-induced muscle damage (EIMD), described as the acute weakness of the musculature after unaccustomed eccentric exercise, increases oxidative metabolism at rest and during endurance exercise. However, it is not known whether oxygen uptake during recovery from endurance exercise is increased when experiencing symptoms of EIMD. Therefore, the purpose of this study was to investigate the effects of EIMD on physiological and metabolic responses before, during and after sub-maximal running. After a 12 h fast, eight healthy male participants completed baseline measurements comprising resting metabolic rate (RMR), indirect markers of EIMD, 10 min of sub-maximal running and 30 min of recovery to ascertain excess post-exercise oxygen consumption (EPOC). Measurements were then repeated at 24 and 48 h after 100 Smith-machine squats. Data analysis revealed significant (PB0.05) increases in muscle soreness and creatine kinase (CK) and decreases in peak knee extensor torque at 24 and 48 h after squatting exercise. Moreover, RMR, physiological, metabolic and perceptual responses during sub-maximal running and EPOC were increased in the two days after squatting exercise (PB0.05). It is suggested that the elevated RMR was a consequence of a raised energy requirement for the degradation and resynthesis of damaged muscle fibres. The increased oxygen demand during sub-maximal running after muscle damage was responsible for the increase in EPOC. Individuals engaging in unaccustomed resistance exercise that results in muscle damage should be mindful of the increases in resting energy expenditure and increased metabolic demand to exercise in the days that follow.
    • The effects of in-season, low-volume sprint interval training with and without sport-specific actions on the physical characteristics of elite academy rugby league players

      Dobbin, Nick; Highton, Jamie M.; Moss, Samantha; Twist, Craig (Human Kinetics, 2020-05-01)
      Purpose: To determine the utility of a running and rugby-specific, in-season sprint interval interventions in professional rugby league players. Methods: Thirty-one professional academy rugby players were assigned to a rugby-specific (SITr/s, n = 16) or running (SITr, n = 15) sprint interval training group. Measures of speed, power, change of direction (CoD) ability, prone Yo-Yo IR1 performance and heart rate recovery (HRR) were taken before and after the 2-week intervention as were sub-maximal responses to the prone Yo-Yo IR1. Internal, external and perceptual responses were collected during SITr/s/SITr, with wellbeing and neuromuscular function assessed before each session. Results: Despite contrasting (possible to most likely) internal, external and perceptual responses to the SIT interventions, possible to most likely within-group improvements in physical characteristics, HRR and sub-maximal responses to the prone Yo-Yo IR1 were observed after both interventions. Between-group analysis favoured the SITr/s intervention (trivial to moderate) for changes in 10 m sprint time, CMJ, change of direction and medicine ball throw as well as sub-maximal (280-440 m) high metabolic power, PlayerLoad™ and acceleratory distance during the prone Yo-Yo IR1. Overall changes in wellbeing or neuromuscular function were unclear. Conclusion: Two-weeks of SITr/s and SITr was effective for improving physical characteristics, HRR and sub-maximal responses to the prone Yo-Yo IR1, with no clear change in wellbeing and neuromuscular function. Between-group analysis favoured the SITr/s group, suggesting that the inclusion of sport- specific actions should be considered for in-season conditioning of rugby league players.
    • The effects of intake of bread with treated corn bran inclusion on postprandial glycaemic response

      Cui, Zhiming; Li, Weili; Kennedy, Lynne; Department of Clinical Sciences and Nutrition, University of Chester
      In the current study, corn bran was treated with hydrothermal processing and then incorporated into bread. The consumption of bread with inclusion of treated corn bran (TCB) and control bread (CB) on postprandial glycaemic response was investigated in a randomised crossover intervention trial with eleven healthy participants and one hyperglycaemicparticipant, capillary blood samples were measured at 0, 15, 30, 45, 60, 75, 90, 105 and 120 minutes after consuming the bread. The results showed the baseline-adjusted peak value of postprandial blood glucose with consumption of CB, containing 75 g carbohydrate was 4.27 mmol/L at 60 min after meal, but with consumption of treated corn bran bread (TCBB), containing 75 g carbohydrate was 3.88 mmol/L at 45 min after meal. In addition, the postprandial blood glucose concentration with consumption of CB is consistently higher than that with the consumption of TCBB since the peak time to 120 min. However, there was no significant differences, in turn, the incremental area under the curves (IAUC) with baseline-adjusted for CB consumption is consistently higher than that of TCBB consumption, but not any significant difference either (p>0.05). However, it is interesting to notice that more considerable difference in rise of blood sugar at peak time and thereafter for hyperglycaemicparticipant between the consumptions of TCBB and CB. In conclusion, the consumption of bread with inclusion of TCB is able to reduce the postprandial glycaemic response to a lower level compared with the consumption of CB and the more obvious difference was observed with the hyperglycaemicparticipant and healthy group Key words: Corn bran, hydrothermal treatment, postprandial glycaemic response. Intervention trial.
    • The effects of physical contact type on the internal and external demands during a rugby league match simulation protocol.

      Norris, Jonathan; Highton, Jamie M.; Hughes, Stephen F.; Twist, Craig; University of Chester (Taylor and Francis, 2016-02-09)
      This study investigated how the type of contact influences physiological, perceptual and locomotive demands during a simulated rugby league match. Eleven male university rugby league players performed two trials of the rugby league movement simulation protocol for forwards (RLMSP-i) with a traditional soft tackle bag (BAG) and a weighted tackle sled (SLED) to replicate contact demands. Locomotive rate, sprint speed, tackle intensity, heart rate, rating of perceived exertion and blood lactate concentration were analysed in four periods during the first and second bout of both trials. Countermovement jump (CMJ) was measured before and immediately after each trial. More time was spent in heart rate zone between 90 – 100% HRpeak during the first (effect size ± 95% confidence interval: 0.44 ± 0.49) and second bout (0.44 ± 0.43), and larger (0.6 ± 0.69) decrements in CMJ performance were observed during SLED (5.9, s = 4.9%) compared to BAG (2.6, s = 5.4%). Sprint into contact speed was faster during BAG compared to SLED in the first (1.10 ± 0.92) and second bout (0.90 ± 0.90), which impaired high intensity running ability but did not increase physiological strain. Changing the type of contact during the match simulation subtly altered both the internal and external load on participants. These findings indicate that tackle training apparatus should be considered regarding the outcome of a training session.
    • The effects of targeted therapy on cell viability and apoptosis on CML and AML cell lines

      Williams, John; Ireland, Elyse; Marsico, Paolo (University of Chester, 2019-01-15)
      Tyrosine kinase inhibitors (TKIs) are currently the first therapy option for chronic myeloid leukaemia (CML) and acute myeloid leukaemia (AML) patients. However, many patients affected by CML and AML may develop resistance to TKIs or may not recover under this treatment regime. New potential and more effective treatments are recently emerging. Heat shock protein inhibitors (HSPIs) and the proteasome inhibitor Bortezomib are drugs which have been yet to be successfully tested on leukemic patients, despite being successful on other malignancies such as multiple myeloma (MM). The combination between HSPIs and Bortezomib could potentially be successful in killing leukemic cells, by enhancing their respective molecular mechanisms. Indeed, HSPIs would bind to HSP72 avoiding the protein to exert its ligase function to the proteasome, whilst Bortezomib could stop the ubiquitinated proteins to enter the proteasome and ultimately inducing apoptosis. To test the effects of such combination, cell viability was measured via MTS assay, apoptosis levels were tested through Annexin V\PI assays. Involvement of HSP72 and pro-survival protein Bcl-2 were measured via flow-cytometry. The cells were administered with HSPIs and Bortezomib first as single agents for 24 hours, to establish working minimal concentration. Also, the drugs were tested for a shorter time, to understand when the drugs start to be effective. It emerged that one hour is sufficient for the drugs to give an initial effect in terms of cell viability and apoptosis. Following, combination experiments of HSPIs and Bortezomib were performed; the first drug was administered for one hour, the second following one hour and the cells were incubated for 24 hours. This was repeated alternatively for both type of drugs on the different cell lines. MTS and Annexin V\PI showed that there is not a synergistic effect between drugs, but instead there is antagonism. No necrosis was found at any level of the study. The cells were then probed for HSP72 and Bcl-2, to investigate their involvement in apoptosis mechanisms. Following 6 hours of combined and single agent treatment, both type of drugs inhibit HSP72 but failed to reduce the expression of Bcl-2, particularly on AML cells. It is thus proposed that CML and AML cells may die by apoptosis following a short time of treatment with HSPIs and Bortezomib by an extrinsic pathway of apoptosis, independent from Bcl-2 involvement and from mitochondrial pathway of apoptosis. This study may be the first to indicate a potential use of HSPIs and Bortezomib on CML and AML patients for a short time of treatment, although not in combination. Future studies are needed to further investigate the mechanisms of action of these drugs, aiming to potentially give CML and AML patients another successful therapy option to overcome resistance to canonic chemotherapy.
    • Effects of temperature and solvent condition on phase separation induced molecular fractionation of gum arabic/hyaluronan aqueous mixtures

      Hu, Bing; Han, Lingyu; Gao, Zhiming; Zhang, Ke; Al-Assaf, Saphwan; Nishinari, Katsuyoshi; Phillips, Glyn O.; Yang, Jixin; Fang, Yapeng; Hubei University of Technology; Wrexham Glyndwr University (Elsevier, 2018-05-14)
      Effects of temperature and solvent condition on phase separation-induced molecular fractionation of gum arabic/hyaluronan (GA/HA) mixed solutions were investigated. Two gum arabic samples (EM10 and STD) with different molecular weights and polydispersity indices were used. Phase diagrams, including cloud and binodal curves, were established by visual observation and GPC-RI methods. The molecular parameters of control and fractionated GA, from upper and bottom phases, were measured by GPC-MALLS. Fractionation of GA increased the content of arabinogalactan-protein complex (AGP) from ca. 11% to 18% in STD/HA system and 28% to 55% in EM10/HA system. The phase separation-induced molecular fractionation was further studied as a function of temperature and solvent condition (varying ionic strength and ethanol content). Increasing salt concentration (from 0.5 to 5 mol/L) greatly reduced the extent of phase separation-induced fractionation. This effect may be ascribed to changes in the degree of ionization and shielding of the acid groups. Increasing temperature (from 4oC to 80oC) also exerted a significant influence on phase separation-induced fractionation. The best temperature for GA/HA mixture system was 40oC while higher temperature negatively affected the fractionation due to denaturation and possibly degradation in mixed solutions. Increasing the ethanol content up to 30% showed almost no effect on the phase separation induced fractionation.
    • Effects of transportation, transport medium and re-housing on Xenopus laevis (Daudin)

      Holmes, Andrew M.; Emmans, Christopher J.; Coleman, Robert C.; Smith, Tessa E.; Hosie, Charlotte A.; University of Chester (Elsevier, 2018-03-12)
      Understanding the immediate and longer-term effects of transportation and re-housing in a laboratory species is crucial in order to refine the transfer process, enable the optimal introduction of new animals to a novel environment and to provide a sufficient acclimatisation period before usage. Whilst consideration of animal welfare in most model vertebrate species has received attention, little quantitative evidence exists for the optimal care of the common laboratory amphibian Xenopus laevis. Techniques for the non-invasive welfare assessment of amphibians are also limited and here a non-invasive physiological assay was developed to investigate the impacts of transportation, transport medium and re-housing on X. laevis. First the impacts of transportation and transport medium (water, damp sponge or damp sphagnum moss) were investigated. Transportation caused an increase in waterborne corticosterone regardless of transport medium. Frogs transported in damp sphagnum moss also had a greater decrease in body mass in comparison to frogs not transported, suggesting that this is the least suitable transport medium for X. laevis. Next the prolonged impacts of transportation and re-housing were investigated. Frogs were transported between research facilities with different housing protocols. Samples were collected prior to and immediately following transportation, as well as 1 day, 7 days and 35 days after re-housing. Water-borne corticosterone increased following transportation and remained high for at least 7 days, decreasing to baseline levels by 35 days. Body mass decreased following transportation and remained lower than baseline levels across the entire 35 day observation period. These findings suggest the process of transportation and re-housing is stressful in this species. Together these findings have important relevance for both improving animal welfare and ensuring optimal and efficient scientific research.