34 research outputs found
Crystal structure of the ferritin from the hyperthermophilic archaeal anaerobe Pyrococcus furiosus
The crystal structure of the ferritin from the archaeon, hyperthermophile and anaerobe Pyrococcus furiosus (PfFtn) is presented. While many ferritin structures from bacteria to mammals have been reported, until now only one was available from archaea, the ferritin from Archaeoglobus fulgidus (AfFtn). The PfFtn 24-mer exhibits the 432 point-group symmetry that is characteristic of most ferritins, which suggests that the 23 symmetry found in the previously reported AfFtn is not a common feature of archaeal ferritins. Consequently, the four large pores that were found in AfFtn are not present in PfFtn. The structure has been solved by molecular replacement and refined at 2.75-Å resolution to R = 0.195 and Rfree = 0.247. The ferroxidase center of the aerobically crystallized ferritin contains one iron at site A and shows sites B and C only upon iron or zinc soaking. Electron paramagnetic resonance studies suggest this iron depletion of the native ferroxidase center to be a result of a complexation of iron by the crystallization salt. The extreme thermostability of PfFtn is compared with that of eight structurally similar ferritins and is proposed to originate mostly from the observed high number of intrasubunit hydrogen bonds. A preservation of the monomer fold, rather than the 24-mer assembly, appears to be the most important factor that protects the ferritin from inactivation by heat
Staff understanding of recovery-orientated mental health practice: a systematic review and narrative synthesis
Background: Mental health policy is for staff to transform their practice towards a recovery orientation. Staff understanding of recovery-orientated practice will influence the implementation of this policy. The aim of this study was to conduct a systematic review and narrative synthesis of empirical studies identifying clinician and manager conceptualisations of recovery-orientated practice.
Methods: A systematic review of empirical primary research was conducted. Data sources were online databases (n = 8), journal table of contents (n = 5), internet, expert consultation (n = 13), reference lists of included studies and references to included studies. Narrative synthesis was used to integrate the findings.
Results: A total of 10,125 studies were screened, 245 full papers were retrieved, and 22 were included (participants, n = 1163). The following three conceptualisations of recovery-orientated practice were identified: clinical recovery, personal recovery and service-defined recovery. Service-defined recovery is a new conceptualisation which translates recovery into practice according to the goals and financial needs of the organisation.
Conclusions: Organisational priorities influence staff understanding of recovery support. This influence is leading to the emergence of an additional meaning of recovery. The impact of service-led approaches to operationalising recovery-orientated practice has not been evaluated.
Trial Registration: The protocol for the review was pre-registered (PROSPERO 2013: CRD42013005942)
Reasons for extractions, and treatment preceding caries-related extractions in 3–8 year-old children
A novel technique using preformed metal crowns for managing carious primary molars in general practice — a retrospective analysis
Background There is a high level of untreated dental decay in primary teeth in Scotland. Despite evidence for the efficacy of preformed metal crowns (PMCs) for the restoration of primary molars, few are placed in general practice, possibly due to the interventive nature of the clinical procedure. There is, however, a novel way of placing PMCs involving no local anaesthesia, no caries removal and no preparation of the tooth: the Hall technique.
Aim To investigate the survival of carious primary teeth treated with PMCs placed using a novel, simplified method — the Hall technique.
Setting General dental practice, in Scotland.
Method A retrospective analysis of practice records from one general practitioner, from 1988 to 2001. The majority of the 978 PMCs fitted on 259 children, using the Hall technique, were placed when there was clinical evidence of approximal caries into dentine. The Kaplan-Meier approach was used to analyse survival times and the Mantel-Haenszel Log rank test for comparison between tooth types.
Results For all tooth types, the probability of surviving three years without being extracted or the PMC being lost, was 73.4% (95% confidence interval 70.1% to 76.4%), and for five years was 67.6% (95% confidence interval 63.3% to 71.5%). The probability of surviving without extraction alone for three years was 86.0% (95% confidence interval 83.2% to 88.4%), and for five years was 80.5% (95% confidence interval 76.5% to 83.9%).
Conclusions Hall technique restorations placed on primary molars with decay clinically into dentine, by a single operator in general dental practice, have a similar success rate to some other, more conventional, restorative techniques. The technique requires further evaluation through a prospective randomised control clinical trial before its use could be generally recommended
The Effects of Retinoic Acid on Early Heart Formation and Segmentation in the Chick Embryo
Molecular signaling in pathogenesis of craniosynostosis: the role of fibroblast growth factor and transforming growth factor–β
The interplay of signals between dura mater, suture mesenchyme, and brain is essential in determining the fate of cranial sutures and the pathogenesis of premature suture fusion leading to craniosynostosis. At the forefront of research into suture fusion is the role of fibroblast growth factor and transforming growth factor-β, which have been found to be critical in the cell-signaling cascade involved in aberrant suture fusion. In this review, the authors discuss recent and ongoing research into the role of fibroblast growth factor and transforming growth factor-β in the etiopathogenesis of craniosynostosis
Oral health-related quality of life: a critical appraisalof assessment tools used in elderly people
A survey of adoption of endodontic nickel-titanium rotary instrumentation part 1: general dental practitioners in Wales
Objective: To assess adoption of endodontic nickel-titanium (NiTi) rotary technology by general dental practitioners and identify factors influencing its uptake.
Design: Postal questionnaire.
Setting: General dental practitioners working in Wales.
Methods: General dental practitioners (n = 584) were approached regarding their usage or otherwise of nickel-titanium rotary instrumentation during root canal shaping. The postal questionnaire took the form of an anonymous survey comprising 13 questions. These questions covered usage parameters, satisfaction, training issues and reasons for avoidance of NiTi instruments.
Results: The response rate was 71%. Nickel-titanium rotary instruments were used routinely by 67% of those responding practitioners. Principle factors cited as being implicated in the decision to not adopt NiTi use included cost (65% of responses), lack of training and the perceived risk of instrument fracture.
Conclusions: Over two thirds of dental practitioners in Wales use rotary NiTi endodontic technology with the majority having converted to such systems more than three years ago. There was, however, a significant disparity in NiTi usage between solely NHS practitioners (42%) and private practitioners (90%). Continued provision of high quality hands-on practical workshops may be of benefit in facilitating a positive initial NiTi experience in order to assist the transfer to these newer technologies