Sprinting with an amputation: Some race-based lower-limb step observations.

BACKGROUND: T44 sprinting with an amputation is still in a state of relative infancy. Future scope for athletic training and prosthetic limb development may be assisted with a better understanding of information derived from T44 athletes when under race-based conditions. OBJECTIVES: To investigate the behaviour of step count and step frequency when under competitive conditions. STUDY DESIGN: The study comprises two elements: (1) a video-based analysis of race-based limb-to-limb symmetry and (2) a video-based analysis of race-based step count. METHODS: Video analysis of several major events from 1996-2012 are assessed for step count and step limb-to-limb symmetry characteristics. RESULTS: The video analysis highlights limb-to-limb imbalances greater than those indicated in the previous literature. A low step count is determined to be desirable for success in the 100-m event. CONCLUSION: Future analysis of athletes with a lower-limb amputation would be worthwhile when placed under race-based conditions as the limb-to-limb behaviour is more exaggerated than those seen in typical studies held within a laboratory setting. The within-event behaviour of step counts requires further investigation to establish where these take place or whether it is a cumulative step length issue. CLINICAL RELEVANCE: This article increases the understanding of the race-based behaviour of amputee athletes and provides more information to contribute to any discussions on the performance of lower-limb prostheses

Dissolution of ionizable water-insoluble drugs: The combined effect of pH and surfactant

This study reports the results of the combined effect of pH and surfactant on the dissolution of piroxicam (PX), an ionizable water-insoluble drug in physiological pH. The intrinsic dissolution rate ( J total ) of PX was measured in the pH range from 4.0 to 7.8 with 0%, 0.5%, and 2.0% sodium lauryl sulfate (SLS) using the rotating disk apparatus. Solubility ( c total ) was also measured in the same pH and SLS concentration ranges. A simple additive model including an ionization (PX ↔ H + + PX − ) and two micellar solubilization equilibria (PX + micelle ↔ [PX] micelle , PX − + micelle ↔ [PX − ] micelle ) were considered in the convective diffusion reaction model. J total and c total of PX increased with increasing pH and SLS concentration in an approximately additive manner. Nonlinear regression analysis showed that observed experimental data were well described with the proposed model ( r 2 = 0.86, P < 0.001 for J total and r 2 = 0.98, P < 0.001 for c total ). The p K a value of 5.63 ± 0.02 estimated from c total agreed well with the reported value. The micellar solubilization equilibrium coefficient for the unionized drug was estimated to be 348 ± 77 L/mol, while the value for the ionized drug was nearly equal to zero. The diffusion coefficients of the species PX, PX − , and [PX] micelle were estimated from the experimental results as (0.93 ± 0.35) × 10 −5 , (1.4 ± 0.30) × 10 −5 , and (0.59 ± 0.21) × 10 −5 cm 2 /s, respectively. The total flux enhancement is less than the total solubility enhancement due to the smaller diffusion coefficients of the micellar species. This model may be useful in predicting the dissolution of an ionizable water insoluble drug as a function of pH and surfactant and for establishing in vitro – in vivo correlations, IVIVC, for maintaining bioequivalence of drug products. © 2000 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 89: 268–274, 2000Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34499/1/14_ftp.pd

Big Food, Food Systems, and Global Health

In an article that forms part of the PLoS Medicine series on Big Food, guest editors David Stuckler and Marion Nestle lay out why more examination of the food industry is necessary, and offer three competing views on how public health professionals might engage with Big Food

Effect of cadence on locomotor–respiratory coupling during upper-body exercise

Introduction: Asynchronous arm-cranking performed at high cadences elicits greater cardiorespiratory responses compared to low cadences. This has been attributed to increased postural demand and locomotor–respiratory coupling (LRC), and yet, this has not been empirically tested. This study aimed to assess the effects of cadence on cardiorespiratory responses and LRC during upper-body exercise. Methods: Eight recreationally-active men performed arm-cranking exercise at moderate and severe intensities that were separated by 10 min of rest. At each intensity, participants exercised for 4 min at each of three cadences (50, 70, and 90 rev min−1) in a random order, with 4 min rest-periods applied in-between cadences. Exercise measures included LRC via whole- and half-integer ratios, cardiorespiratory function, perceptions of effort (RPE and dyspnoea), and diaphragm EMG using an oesophageal catheter. Results: The prevalence of LRC during moderate exercise was highest at 70 vs. 50 rev min−1 (27 ± 10 vs. 13 ± 9%, p = 0.000) and during severe exercise at 90 vs. 50 rev min−1 (24 ± 7 vs. 18 ± 5%, p = 0.034), with a shorter inspiratory time and higher mean inspiratory flow (p < 0.05) at higher cadences. During moderate exercise, (Formula presented.) and fC were higher at 90 rev min−1 (p < 0.05) relative to 70 and 50 rev min−1 ((Formula presented.) 1.19 ± 0.25 vs. 1.05 ± 0.21 vs. 0.97 ± 0.24 L min−1; fC 116 ± 11 vs. 101 ± 13 vs. 101 ± 12 b min−1), with concomitantly elevated dyspnoea. There were no discernible cadence-mediated effects on diaphragm EMG. Conclusion: Participants engage in LRC to a greater extent at moderate-high cadences which, in turn, increase respiratory airflow. Cadence rate should be carefully considered when designing aerobic training programmes involving the upper-limbs

School nurses' experiences of delivering the UK HPV vaccination programme in its first year

Background: In the United Kingdom (UK) in September 2008, school nurses began delivering the HPV immunisation programme for girls aged 12 and 13 years old. This study offers insights from school nurses' perspectives and experiences of delivering this new vaccination programme. Methods: Thirty in-depth telephone interviews were conducted with school nurses working across the UK between September 2008 and May 2009. This time period covers the first year of the HPV vaccination programme in schools. School nurses were recruited via GP practices, the internet and posters targeted at school nurse practitioners. Results: All the school nurses spoke of readying themselves for a deluge of phone calls from concerned parents, but found that in fact few parents telephoned to ask for more information or express their concerns about the HPV vaccine. Several school nurses mentioned a lack of planning by policy makers and stated that at its introduction they felt ill prepared. The impact on school nurses' workload was spoken about at length by all the school nurses. They believed that the programme had vastly increased their workload leading them to cut back on their core activities and the time they could dedicate to offering support to vulnerable pupils. Conclusion: Overall the first year of the implementation of the HPV vaccination programme in the UK has exceeded school nurses' expectations and some of its success may be attributed to the school nurses' commitment to the programme. It is also the case that other factors, including positive newsprint media reporting that accompanied the introduction of the HPV vaccination programme may have played a role. Nevertheless, school nurses also believed that the programme had vastly increased their workload leading them to cut back on their core activities and as such they could no longer dedicate time to offer support to vulnerable pupils. This unintentional aspect of the programme may be worthy of further exploratio

How paradata can illuminate technical, social and professional role changes between the Poverty in the UK (1967/1968) and Poverty and Social Exclusion in the UK (2012) surveys

© 2016, The Author(s). This article brings together analyses of the micro paradata ‘by-products’ from the 1967/1968 Poverty in the United Kingdom (PinUK) and 2012 Poverty and Social Exclusion in the UK (PSE) surveys to explore changes in the conditions of production over this 45year period. We highlight technical, social and professional role continuities and changes, shaped by the institutionalisation of survey researchers, the professionalization of the field interviewer, and economisation. While there are similarities between the surveys in that field interviewers were and are at the bottom of the research hierarchy, we demonstrate an increasing segregation between the core research team and field interviewers. In PinUK the field interviewers are visible in the paper survey booklets; through their handwritten notes on codes and in written marginalia they can ‘talk’ to the central research team. In PSE they are absent from the computer mediated data, and from communication with the central team. We argue that, while there have been other benefits to field interviewers, their relational labour has become less visible in a shift from the exercise of observational judgement to an emphasis on standardisation. Yet, analyses of what field interviewers actually do show that they still need to deploy the same interpersonal skills and resourcefulness to secure and maintain interviews as they did 45years previously

Evidence for physical activity guidelines as a public health intervention: efficacy, effectiveness and harm – a critical policy sciences approach.

BACKGROUND: Evidence for the efficacy of physical activity in conferring health benefits is unequivocal, and this has led national governments to produce guideline recommendations for physical activity levels in their populations. AIM: To evaluate how far evidence for the efficacy, effectiveness and comparative effectiveness of current physical activity guideline recommendations as a public health intervention is considered in developing guideline recommendations, including a consideration of the extent to which, in comparison to alternatives, they may result in harm. METHODS: Utilising a critical policy sciences approach, national physical activity guideline recommendations in Australia, the UK and the USA, and those of the World Health Organisation, are examined, along with their stated underlying evidence bases, to analyse what evidence has been considered, how it has been interpreted, for what purpose, and with what outcomes. RESULTS: All current guidelines recommend 150 minutes moderate physical activity per week. However, efficacy evidence shows 60 minutes is sufficient to provide some health benefits. None of the guidelines consider effectiveness evidence nor potential effectiveness. No evidence could be found for the effectiveness of a recommendation of 150 minutes in improving population health, and none of the guidelines consider whether a recommendation at a lower but still sufficient level of efficacy (e.g. 60 minutes) would be a more effective public health intervention. CONCLUSIONS: Evidence considered in drawing up physical activity guidelines relates only to the efficacy of physical activity in conferring health benefits. The lack of effectiveness evidence, the failure to consider potential effectiveness, and related un-evidenced value judgements call into question the claim that the guidelines are evidence-based. Because neither effectiveness nor comparative effectiveness is considered, it is possible that current guidelines of 150 minutes may result in net harm to population health in comparison to the opportunity cost of recommendations at alternative levels

In vitro culturing of porcine tracheal mucosa as an ideal model for investigating the influence of drugs on human respiratory mucosa

It has been previously shown that fresh mucosa from different mammals could serve as raw material for in vitro culturing with the differentiation of cilia, which are the most important morphological structures for the function of the mucociliary system. Increasing legal restrictions on the removal of human tissue and changing surgical techniques have led to a lack of fresh human mucosa for culturing. Most of the animals that have been used as donors up to now are genetically not very close to human beings and must all be sacrificed for such studies. We, therefore, established a modified system of culturing mucosa cells from the trachea of pigs, which is available as a regular by-product after slaughtering. With respect to the possibility of developing “beating” cilia, it could be shown that the speed of cell proliferation until adhesion to the coated culture dishes, the formation of conjunctions of cell clusters and the proliferation of cilia were comparable for porcine and human mucosa. Moreover, it could be demonstrated that the porcine cilia beat frequency of 7.57 ± 1.39 Hz was comparable to the human mucosa cells beat frequency of 7.3 ± 1.4 Hz and that this beat frequency was absolutely constant over the investigation time of 360 min. In order to prove whether the reaction to different drugs is comparable between the porcine and human cilia, we initially tested benzalkonium chloride, which is known to be toxic for human cells, followed by naphazoline, which we found in previous studies on human mucosa to be non-toxic. The results clearly showed that the functional and morphological reactions of the porcine ciliated cells to these substances were similar to the reaction we found in the in vitro cultured human mucosa

Molecular Imaging of Pulmonary Tuberculosis in an Ex-Vivo Mouse Model Using Spectral Photon-Counting Computed Tomography and Micro-CT

Assessment of disease burden and drug efficacy is achieved preclinically using high resolution micro computed tomography (CT). However, micro-CT is not applicable to clinical human imaging due to operating at high dose. In addition, the technology differences between micro-CT and standard clinical CT prevent direct translation of preclinical applications. The current proof-of-concept study presents spectral photon-counting CT as a clinically translatable, molecular imaging tool by assessing contrast uptake in an ex-vivo mouse model of pulmonary tuberculosis (TB). Iodine, a common contrast used in clinical CT imaging, was introduced into a murine model of TB. The excised mouse lungs were imaged using a standard micro-CT subsystem (SuperArgus) and the contrast enhanced TB lesions quantified. The same lungs were imaged using a spectral photoncounting CT system (MARS small-bore scanner). Iodine and soft tissues (water and lipid) were materially separated, and iodine uptake quantified. The volume of the TB infection quantified by spectral CT and micro-CT was found to be 2.96 mm(3) and 2.83 mm(3), respectively. This proof-of-concept study showed that spectral photon-counting CT could be used as a predictive preclinical imaging tool for the purpose of facilitating drug discovery and development. Also, as this imaging modality is available for human trials, all applications are translatable to human imaging. In conclusion, spectral photon-counting CT could accelerate a deeper understanding of infectious lung diseases using targeted pharmaceuticals and intrinsic markers, and ultimately improve the efficacy of therapies by measuring drug delivery and response to treatment in animal models and later in humans