Risk of second cancers in the era of modern radiation therapy: does the risk/benefit analysis overcome theoretical models?

In the era of modern radiation therapy, the compromise between the reductions in deterministic radiation-induced toxicities through highly conformal devices may be impacting the stochastic risk of second malignancies. We reviewed the clinical literature and evolving theoretical models evaluating the impact of intensity-modulated radiation therapy (IMRT) on the risk of second cancers, as a consequence of the increase in volumes of normal tissues receiving low doses. The risk increase (if any) is not as high as theoretical models have predicted in adults. Moreover, the increase in out-of-field radiation doses with IMRT could be counterbalanced by the decrease in volumes receiving high doses. Clinical studies with short follow-up have not corroborated the hypothesis that IMRT would drastically increase the incidence of second cancers. In children, the risk of radiation-induced carcinogenesis increases from low doses and consequently the relative risk of second cancers after IMRT could be higher than in adults, justifying current developments of proton therapy with priority given to this population. Although only longer follow-up will allow a true assessment of the real impact of these modern techniques on radiation-induced carcinogenesis, a comprehensive risk-adapted strategy will help minimize the probability of second cancers.     

Mechanical model of blebbing in nuclear lamin meshworks

Much of the structural stability of the nucleus comes from meshworks of intermediate filament proteins known as lamins forming the inner layer of the nuclear envelope called the nuclear lamina. These lamin meshworks additionally play a role in gene expression. Abnormalities in nuclear shape are associated with a variety of pathologies, including some forms of cancer and Hutchinson–Gilford Progeria Syndrome, and often include protruding structures termed nuclear blebs. These nuclear blebs are thought to be related to pathological gene expression; however, little is known about how and why blebs form. We have developed a minimal continuum elastic model of a lamin meshwork that we use to investigate which aspects of the meshwork could be responsible for bleb formation. Mammalian lamin meshworks consist of two types of lamin proteins, A type and B type, and it has been reported that nuclear blebs are enriched in A-type lamins. Our model treats each lamin type separately and thus, can assign them different properties. Nuclear blebs have been reported to be located in regions where the fibers in the lamin meshwork have a greater separation, and we find that this greater separation of fibers is an essential characteristic for generating nuclear blebs. The model produces structures with comparable morphologies and distributions of lamin types as real pathological nuclei. Thus, preventing this opening of the meshwork could be a route to prevent bleb formation, which could be used as a potential therapy for the pathologies associated with nuclear blebs.     

Periarticular infiltration in total hip replacement: effect on heterotopic ossification,analgesic requirements and outcome

Background  

Up to 80% of patients develop heterotopic ossification (HO) following total hip replacement (THR) and high grades may adversely affect outcome. This study investigated the influence of local infiltration of a NSAID (Ketorolac) and local anaesthetic on the incidence and grade of HO following THR, the effect on post-operative opiate analgesic requirement and on patient reported outcome score.     

"Don't wait for them to come to you, you go to them". A qualitative study of recruitment approaches in community based walking programmes in the UK

ABSTRACT: BACKGROUND: This study aimed to examine the experiences of walking promotion professionals on the range and effectiveness of recruitment strategies used within community based walking programmes within the United Kingdom. METHODS: Two researchers recruited and conducted semi-structured interviews with managers and project co-ordinators of community based walking programmes, across the UK, using a purposive sampling frame. Twenty eight interviews were conducted, with community projects targeting participants by age, physical activity status, socio-demographic characteristics (i.e. ethnic group) or by health status. Three case studies were also conducted with programmes aiming to recruit priority groups and also demonstrating innovative recruitment methods. Data analysis adopted an approach using analytic induction. RESULTS: Two types of programmes were identified: those with explicit health aims and those without. Programme aims which required targeting of specific groups adopted more specific recruitment methods. The selection of recruitment method was dependent on the respondent's awareness of 'what works' and the resource capacity at their disposal. Word of mouth was perceived to be the most effective means of recruitment but using this approach took time and effort to build relationships with target groups, usually through a third party. Perceived effectiveness of recruitment was assessed by number of participants rather than numbers of the right participants. Some programmes, particularly those targeting younger adult participants, recruited using new social communication media. Where adopted, social marketing recruitment strategies tended to promote the 'social' rather than the 'health' benefits of walking. CONCLUSIONS: Effective walking programme recruitment seems to require trained, strategic, labour intensive, word-of-mouth communication, often in partnerships, in order to understand needs and develop trust and motivation within disengaged sedentary communities. Walking promotion professionals require better training and resources to deliver appropriate recruitment strategies to reach priority groups.     

Promoting HIV and sexual safety behaviour in people with severe mental illness: A systematic review of behavioural interventions

People diagnosed with severe mental illness (SMI) are at greater risk of HIV than the general population. However, little attention has been given to how best to reduce sexual risk taking in this group. The aim of the review was to evaluate the effectiveness of behavioural interventions to promote sexual safety behaviour in people diagnosed with SMI. A comprehensive search of relevant databases was undertaken, and studies were included if they were randomized, controlled trials; behavioural intervention related to sexual behaviour; included adults diagnosed with SMI; and if a behavioural outcome was reported. The Cochrane Assessment of Bias Tool was used. Of the initial 515 papers identified, 11 trials were included for quality assessment and data extraction. The studies were heterogeneous in content and dose of intervention, as well as outcome measure and follow‐up periods, and all had some risk of bias. Four of the studies demonstrated significant improvement in safer sexual behaviour at follow up, but this effect diminished over time. The effect sizes were extremely variable. There is emerging evidence to suggest that a behavioural intervention has the potential to reduce sexual risks in people diagnosed with SMI. However, further high‐quality research is needed in this area.