DHX9-dependent recruitment of BRCA1 to RNA promotes DNA end resection in homologous recombination

Double stranded DNA Breaks (DSB) that occur in highly transcribed regions of the genome are preferentially repaired by homologous recombination repair (HR). However, the mechanisms that link transcription with HR are unknown. Here we identify a critical role for DHX9, a RNA helicase involved in the processing of pre-mRNA during transcription, in the initiation of HR. Cells that are deficient in DHX9 are impaired in the recruitment of RPA and RAD51 to sites of DNA damage and fail to repair DSB by HR. Consequently, these cells are hypersensitive to treatment with agents such as camptothecin and Olaparib that block transcription and generate DSB that specifically require HR for their repair. We show that DHX9 plays a critical role in HR by promoting the recruitment of BRCA1 to RNA as part of the RNA Polymerase II transcription complex, where it facilitates the resection of DSB. Moreover, defects in DHX9 also lead to impaired ATR-mediated damage signalling and an inability to restart DNA replication at camptothecin-induced DSB. Together, our data reveal a previously unknown role for DHX9 in the DNA Damage Response that provides a critical link between RNA, RNA Pol II and the repair of DNA damage by homologous recombination

The use and effectiveness of the eLib subject gateways: a preliminary investigation

Internet subject gateways were set up under the Electronic Libraries Programme (eLib) in order to address some of the problems of searching the Internet which have been identified by information professionals, i.e. locating relevant, good quality information. This preliminary study examines the extent to which academics in two universities use three eLib subject gateways (EEVL, OMNI and SOSIG). The results are generally encouraging for the eLib programme, but it is necessary for the gateways to be more effectively promoted. The study also found that academics do not have the same misgivings about the general search engines as the information professionals and seem to use them more readily than the gateways

Assessing awareness of colorectal cancer symptoms: Measure development and results from a population survey in the UK

Background: This paper describes the development of a Cancer Awareness Measure for colorectal (CRC) cancer (Bowel/Colorectal CAM(a)) (study 1) and presents key results from a population-representative survey using the measure (study 2).MethodsStudy 1: Items were taken from the literature and reviewed by expert groups. A series of three validation studies assessed reliability and validity of the measure. To establish test-retest reliability, 49 people over 50 years of age completed the Bowel/Colorectal CAM on two occasions (range 9-14 days, mean 13.5 days). Construct validity was assessed by comparing responses from bowel cancer experts (n = 16) and the lay public (n = 35). Lastly, a brief intervention study tested sensitivity to change with participants (n = 70) randomly allocated to be given a control leaflet or an intervention leaflet and their responses were compared. Study 2: 1520 respondents completed the Bowel/Colorectal CAM in a population survey carried out by TNS-British Market Research Bureau International (TNS-BMRB) in March 2010.ResultsStudy 1: Internal reliability (Cronbach's alpha = 0.84) was high. Test-retest reliability was over r = 0.7 for warning signs, risk factors and age people are first invited for screening, but lower (between 0.6 and 0.7) for other items (lifetime risk, awareness of bowel cancer screening, age at risk). Bowel cancer experts achieved higher scores than equally educated controls (54.7 [4.3] vs. 42.9 [5.7]; P < 0.001) demonstrating the measure has construct validity and intervention participants showed higher knowledge than controls (51.4 [5.9] vs. 42.9 [5.7]; P < 0.001) suggesting the measure is sensitive to change. Study 2: Respondents recalled on average, one CRC sign and one risk factor. There was particularly low prompted awareness of the signs 'lump in the abdomen' (64%) and 'tiredness' (50%) and several lifestyle risk factors for CRC, e. g. exercise (37%). Respondents from more affluent groups had consistently higher knowledge of signs and risk factors compared to those from more deprived groups.Conclusions: The Bowel/Colorectal CAM meets accepted psychometric criteria for reliability and construct validity and should therefore provide a useful tool for assessment of CRC awareness. The population survey revealed low awareness of several CRC signs and risk factors and emphasises the importance of continuing public education, particularly about the link between lifestyle behaviours and CRC

Sunbed use in children aged 11-17 in England: face to face quota sampling surveys in the National Prevalence Study and Six Cities Study

Objectives To quantify the use of sunbeds in young people across England, identify geographical variation, and explore patterns of use, including supervision

Topical gabapentin gel alleviates allodynia and hyperalgesia in the chronic sciatic nerve constriction injury neuropathic pain model

Background: Systemic gabapentin is a mainstay treatment for neuropathic pain though there are side effects. Localized therapy may curtail such side effects so a topical gabapentin dermal application was examined in the chronic constriction injury (CCI) model of neuropathic pain. Methods: Partial denervation CCI was achieved by rat sciatic nerve ligation. Gabapentin gel (10% w/w) was applied three-times daily on the ipsilateral or contralateral plantar surface of the hind-paw while in a concurrent systemic study, gabapentin was intraperitoneally administered daily (75 mg/kg) for 30 days. Tests for static- and dynamic- mechano-allodynia (paw withdrawal threshold [PWT] to von-Frey filament application and latency [PWL] to light brushing), coldallodynia (paw withdrawal duration [PWD] to acetone), heat- (PWL and PWD) and mechanohyperalgesia (PWD to pin-prick) were utilized to assess pain while effects on locomotion (open field) and motor balance (rotarod and footprint-analysis) were measured on days 5-30 postsurgery. Results: Topical application of gabapentin gel ipsilaterally but not contralaterally alleviated CCI-induced static- (days 10-30) and dynamic-allodynia (days 15-30), suppressed cold-allodynia (days 10-30), heat- (days 15-30) and mechano-hyperalgesia (days 5-30) indicating a local action. Systemic gabapentin exhibited similar pain profiles but was associated with motor impairment. The gabapentin gel formulation afforded desirable neuropathic pain alleviating effects devoid of unwanted systemic side-effects. Conclusions: These outcomes disclose an expedient pharmacological validation of the effectiveness of topical gabapentin gel against an extensive range of nociceptive stimulus modalities utilizing the CCI-induced neuropathic pain model. They also advocate further clinical studies on topical gabapentin with regard to certain neuropathic pain syndromes

National Cancer Diagnosis Audits for England 2018 versus 2014: a comparative analysis

BACKGROUND: Timely diagnosis of cancer in patients who present with symptoms in primary care is a quality-improvement priority. AIM: To examine possible changes to aspects of the diagnostic process, and its timeliness, before and after publication of the National Institute for Health and Care Excellence's (2015) guidance on the referral of suspected cancer in primary care. DESIGN AND SETTING: Comparison of findings from population-based clinical audits of cancer diagnosis in general practices in England for patients diagnosed in 2018 or 2014. METHOD: GPs in 1878 (2018) and 439 (2014) practices collected primary care information on the diagnostic pathway of cancer patients. Key measures including patient characteristics, place of presentation, number of pre-referral consultations, use of primary care investigations, and referral type were compared between the two audits by descriptive analysis and regression models. RESULTS: Among 64 489 (2018) and 17 042 (2014) records of a new cancer diagnosis, the percentage of patients with same-day referral (denoted by a primary care interval of 0 days) was higher in 2018 (42.7% versus 37.7%) than in 2014, with similar improvements in median diagnostic interval (36 days versus 40 days). Compared with 2014, in 2018: fewer patients had ≥3 pre-referral consultations (18.8% versus 26.2%); use of primary care investigations increased (47.9% versus 45.4%); urgent cancer referrals increased (54.8% versus 51.8%); emergency referrals decreased (13.4% versus 16.5%); and recorded use of safety netting decreased (40.0% versus 44.4%). CONCLUSION: In the 5-year period, including the year when national guidelines were updated (that is, 2015), there were substantial improvements to the diagnostic process of patients who present to general practice in England with symptoms of a subsequently diagnosed cancer

Development and evaluation of topical gabapentin formulations

Topical delivery of gabapentin is desirable to treat peripheral neuropathic pain conditions whilst avoiding systemic side effects. To date, reports of topical gabapentin delivery in vitro have been variable and dependent on the skin model employed, primarily involving rodent and porcine models. In this study a variety of topical gabapentin formulations were investigated, including Carbopol® hydrogels containing various permeation enhancers, and a range of proprietary bases including a compounded Lipoderm® formulation; furthermore microneedle facilitated delivery was used as a positive control. Critically, permeation of gabapentin across a human epidermal membrane in vitro was assessed using Franz-type diffusion cells. Subsequently this data was contextualised within the wider scope of the literature. Although reports of topical gabapentin delivery have been shown to vary, largely dependent upon the skin model used, this study demonstrated that 6% (w/w) gabapentin 0.75% (w/w) Carbopol® hydrogels containing 5% (w/w) DMSO or 70% (w/w) ethanol and a compounded 10% (w/w) gabapentin Lipoderm® formulation were able to facilitate permeation of the molecule across human skin. Further pre-clinical and clinical studies are required to investigate the topical delivery performance and pharmacodynamic actions of prospective formulations

Public awareness of cancer in Britain: a population-based survey of adults

*_Objective:_* To assess public awareness of cancer warning signs, anticipated delay, and perceived barriers to seeking medical advice in the British population. &#xd;&#xa;Methods: We carried out a population-based survey using face-to-face, computer-assisted interviews to administer the Cancer Awareness Measure (CAM), a newly-developed, validated measure of cancer awareness. The sample included 2216 adults (970 male and 1246 female) recruited as part of the Office for National Statistics Opinions Survey using stratified probability sampling.&#xd;&#xa;&#xd;&#xa;*_Results:_* Awareness of cancer warning signs was low when open-ended (recall) questions were used and higher with closed (recognition) questions; but on either measure, awareness was lower in those who were male, younger, and from lower socioeconomic status (SES) groups or ethnic minorities. The most commonly endorsed barriers to help-seeking were difficulty making an appointment, worry about wasting the doctor&#x2019;s time and worry about what would be found. Emotional barriers were more prominent in lower SES groups and practical barriers (e.g. too busy) more prominent in higher SES groups. Anticipated delay was lower in ethnic minority and lower SES groups. In multivariate analysis, higher symptom awareness was associated with lower anticipated delay, and more barriers with greater anticipated delay.&#xd;&#xa;&#xd;&#xa;*_Conclusions:_* A combination of public education about symptoms and empowerment to seek medical advice, as well as support at primary care level, could enhance early presentation and improve cancer outcomes

A Functional Analysis of the Spacer of V(D)J Recombination Signal Sequences

During lymphocyte development, V(D)J recombination assembles antigen receptor genes from component V, D, and J gene segments. These gene segments are flanked by a recombination signal sequence (RSS), which serves as the binding site for the recombination machinery. The murine Jβ2.6 gene segment is a recombinationally inactive pseudogene, but examination of its RSS reveals no obvious reason for its failure to recombine. Mutagenesis of the Jβ2.6 RSS demonstrates that the sequences of the heptamer, nonamer, and spacer are all important. Strikingly, changes solely in the spacer sequence can result in dramatic differences in the level of recombination. The subsequent analysis of a library of more than 4,000 spacer variants revealed that spacer residues of particular functional importance are correlated with their degree of conservation. Biochemical assays indicate distinct cooperation between the spacer and heptamer/nonamer along each step of the reaction pathway. The results suggest that the spacer serves not only to ensure the appropriate distance between the heptamer and nonamer but also regulates RSS activity by providing additional RAG:RSS interaction surfaces. We conclude that while RSSs are defined by a “digital” requirement for absolutely conserved nucleotides, the quality of RSS function is determined in an “analog” manner by numerous complex interactions between the RAG proteins and the less-well conserved nucleotides in the heptamer, the nonamer, and, importantly, the spacer. Those modulatory effects are accurately predicted by a new computational algorithm for “RSS information content.” The interplay between such binary and multiplicative modes of interactions provides a general model for analyzing protein–DNA interactions in various biological systems