Crucial roles of the BRCA1-BARD1 E3 ubiquitin ligase activity in homology-directed DNA repair.

The tumor-suppressor breast cancer 1 (BRCA1) in complex with BRCA1-associated really interesting new gene (RING) domain 1 (BARD1) is a RING-type ubiquitin E3 ligase that modifies nucleosomal histone and other substrates. The importance of BRCA1-BARD1 E3 activity in tumor suppression remains highly controversial, mainly stemming from studying mutant ligase-deficient BRCA1-BARD1 species that we show here still retain significant ligase activity. Using full-length BRCA1-BARD1, we establish robust BRCA1-BARD1-mediated ubiquitylation with specificity, uncover multiple modes of activity modulation, and construct a truly ligase-null variant and a variant specifically impaired in targeting nucleosomal histones. Cells expressing either of these BRCA1-BARD1 separation-of-function alleles are hypersensitive to DNA-damaging agents. Furthermore, we demonstrate that BRCA1-BARD1 ligase is not only required for DNA resection during homology-directed repair (HDR) but also contributes to later stages for HDR completion. Altogether, our findings reveal crucial, previously unrecognized roles of BRCA1-BARD1 ligase activity in genome repair via HDR, settle prior controversies regarding BRCA1-BARD1 ligase functions, and catalyze new efforts to uncover substrates related to tumor suppression.

Promotion of DNA end resection by BRCA1-BARD1 in homologous recombination.

The licensing step of DNA double-strand break repair by homologous recombination entails resection of DNA ends to generate a single-stranded DNA template for assembly of the repair machinery consisting of the RAD51 recombinase and ancillary factors1. DNA end resection is mechanistically intricate and reliant on the tumour suppressor complex BRCA1-BARD1 (ref. 2). Specifically, three distinct nuclease entities-the 5'-3' exonuclease EXO1 and heterodimeric complexes of the DNA endonuclease DNA2, with either the BLM or WRN helicase-act in synergy to execute the end resection process3. A major question concerns whether BRCA1-BARD1 directly regulates end resection. Here, using highly purified protein factors, we provide evidence that BRCA1-BARD1 physically interacts with EXO1, BLM and WRN. Importantly, with reconstituted biochemical systems and a single-molecule analytical tool, we show that BRCA1-BARD1 upregulates the activity of all three resection pathways. We also demonstrate that BRCA1 and BARD1 harbour stand-alone modules that contribute to the overall functionality of BRCA1-BARD1. Moreover, analysis of a BARD1 mutant impaired in DNA binding shows the importance of this BARD1 attribute in end resection, both in vitro and in cells. Thus, BRCA1-BARD1 enhances the efficiency of all three long-range DNA end resection pathways during homologous recombination in human cells.

Risk factors and timing of postoperative hematomas following microvascular breast reconstruction: A prospective cohort study.

BACKGROUND: Microvascular free tissue transfer has become the gold standard for breast reconstruction. While safe and reliable, there are operative complications, with hematomas developing under the free flap among the more common. These can compromise flap viability, lead to hemodynamic instability and infection. This study aims to identify predictors of hematomas following free-flap breast reconstruction. METHODS: A prospective study was undertaken of patients undergoing autologous free-flap breast reconstruction over a 4-year period. Precise times to hematoma formation, age, arterial and venous anastomosis time, and anastomosis length were recorded and analyzed for association with time to hematoma formation. RESULTS: One thousand two hundred twelve flaps were undertaken in 1,070 patients during the period of review. Seventy-one (5.8%) flaps were taken back to theater for hematomas. Immediate reconstruction had a significantly higher hematoma rate compared to delayed reconstruction 7.4% versus 5.2% (p < .001). It is noted that there were two main peaks for time to develop hematomas-less than 4 hr postsurgery and between 12 and 15 hr postsurgery. CONCLUSION: Hematomas are a complication, which must be managed with prompt return to theater to ensure flap salvage and patient stabilization. Predictors for hematoma are presented, with hematomas most likely encountered within the first 12 hr of surgery.

Technical refinements of the free medial sural artery perforator (MSAP) flap in reconstruction of multifaceted ankle soft tissue defects.

BACKGROUND: Peri-ankle defects are difficult to reconstruct due to sharp contours, thin skin, aesthetic value, function and footwear impact. The medial sural artery perforator flap (MSAP) is increasing in popularity as a thin and pliable flap. This study aims to demonstrate its versatility in reconstructing defects around the ankle area and our approach to insetting these flaps in difficult areas around the ankle without the need for subsequent flap revisions. METHODS: A retrospective review of the senior author's series of peri-ankle reconstructions using the MSAP flap was undertaken. RESULTS: Between 2011-2015, 15 patients underwent peri-ankle reconstruction with the MSAP flap. There were 4 dorsal foot, 4 medial malleolar, 4 lateral malleolar, and 3 tendo-achilles defects. All flaps in this series survived. There was one episode of partial flap necrosis in one patient and no incidences of donor site dehiscence. All patients returned to full ambulation and none required subsequent flap revision. CONCLUSIONS: The MSAP flap offers the benefits of a fasciocutaneous flap, whilst providing a thin, pliable, single stage and robust reconstruction for peri-ankle defects, with a cosmetically ideal donor site.

Ankylosing Spondylitis Response to TNF Inhibition Is Gender Specific: A 6-Year Cohort Study

Aim Recent studies have suggested gender-specific differences with respect to both baseline disease activity and severity in ankylosing spondylitis (AS). Tumour necrosis factor inhibitors (TNFi) have shown significant benefit in AS but there may be gender-specific differences regarding responses to TNFi therapy. Methods AS patients with active disease despite adequate trials of NSAIDs were commenced on TNFi and followed in a biologic clinic between 2004 and 2011. Response to treatment was measured based on clinical and serological outcomes. Baseline radiographic data were also collected where available. Results 147 AS patients commenced TNFi therapy and were followed in a biologic clinic between 2004 and 2011. One-hundred and six (72%) of the patients were male and 90 (61%) were current or ex-smokers. The specific TNFi prescribed included etanercept (74 patients, 50.3%), adalimumab (51 patients, 34.7%), infliximab (21 patients, 14.2%) and golimumab (1 patient, 0.7%). The median mSASSS score was 11 (interquartile range 5-35). At baseline, the metrology indices (BASMI) were significantly lower in women (2.6 v 4; p=0.01) but all other clinical indices were similar. At 3 months, female patients had significantly worse median disease activity and functional indices (BASDAI: 4 v 2; p<0.01; BASFI: 3 v 2; p=0.03) than male patients. In addition, females had higher median ESR (19 v 6; p<0.01) which correlated with their disease activity indices (r=0.42, p=0.02). Discussion Despite similar disease activity at baseline, post-TNFi therapy women had significantly higher disease activity. Furthermore, ESR levels in women during therapy correlated with their clinical disease activity scores. Further exploration of these gender-specific differences is crucial for a greater understanding of the pathogenesis of AS as well as development of targeted therapies.

European League Against Rheumatism (EULAR) recommendations for the management of psoriatic arthritis with pharmacological therapies: 2015 update.

BACKGROUND: Since the publication of the European League Against Rheumatism recommendations for the pharmacological treatment of psoriatic arthritis (PsA) in 2012, new evidence and new therapeutic agents have emerged. The objective was to update these recommendations. METHODS: A systematic literature review was performed regarding pharmacological treatment in PsA. Subsequently, recommendations were formulated based on the evidence and the expert opinion of the 34 Task Force members. Levels of evidence and strengths of recommendations were allocated. RESULTS: The updated recommendations comprise 5 overarching principles and 10 recommendations, covering pharmacological therapies for PsA from non-steroidal anti-inflammatory drugs (NSAIDs), to conventional synthetic (csDMARD) and biological (bDMARD) disease-modifying antirheumatic drugs, whatever their mode of action, taking articular and extra-articular manifestations of PsA into account, but focusing on musculoskeletal involvement. The overarching principles address the need for shared decision-making and treatment objectives. The recommendations address csDMARDs as an initial therapy after failure of NSAIDs and local therapy for active disease, followed, if necessary, by a bDMARD or a targeted synthetic DMARD (tsDMARD). The first bDMARD would usually be a tumour necrosis factor (TNF) inhibitor. bDMARDs targeting interleukin (IL)12/23 (ustekinumab) or IL-17 pathways (secukinumab) may be used in patients for whom TNF inhibitors are inappropriate and a tsDMARD such as a phosphodiesterase 4-inhibitor (apremilast) if bDMARDs are inappropriate. If the first bDMARD strategy fails, any other bDMARD or tsDMARD may be used. CONCLUSIONS: These recommendations provide stakeholders with an updated consensus on the pharmacological treatment of PsA and strategies to reach optimal outcomes in PsA, based on a combination of evidence and expert opinion.

Cochlear implantation in children with sickle cell disease.

Sickle cell disease (SCD) is associated with sensorineural hearing loss (SNHL). Although the hearing loss is usually mild, some develop severe-to-profound hearing loss, in whom cochlear implants (CI) may be an option. We present the cases of two children with SCD who developed bilateral severe-to-profound SNHL and underwent cochlear implantation. One patient became profoundly deaf after an acute episode of dizziness. Imaging indicated bilateral cochlear ossification, making subsequent cochlear implant surgery challenging. The second patient developed bilateral severe-to-profound SNHL following acute vaso-occlusive crises. She went on to have uncomplicated cochlear implant surgery. These cases illustrate the variable manner in which children with SCD may develop SNHL, and the difficulties associated with managing such cases. We recommend that children with SCD should undergo regular audiological assessment. Furthermore, clinicians should be aware of the risk of cochlear fibrosis and ossification and ensure prompt assessment following an acute vaso-occlusive crisis or unexplained vestibulocochlear event.

Guideline Promotion Increases Prescription of Bone Protection with Steroids in Hospitalised Patients.

Guidelines for the prevention of glucocorticoid (GC) induced osteoporosis (GIOP) were implemented in a level 5 Irish Hospital with cross sectional audit of inpatient prescribing undertaken before and after. Prior to guideline implementation, elemental calcium (Ca) with Vitamin D (VitD) was prescribed for 11/66 (17%) of patients on GCs with 2/66 (3%) also receiving bisphosphonate (BP) therapy. Subsequent to guideline implementation, Ca with VitD was prescribed for 19/55 (35%) of patients on GCs with 11/55 (20%) also receiving BP therapy, representing a 2 and 6 fold respective increase. Internal promotion of guidelines is an effective strategy for healthcare improvement but needs refinement with or without repetition to achieve better patient outcomes.

Treating axial and peripheral spondyloarthritis, including psoriatic arthritis, to target: results of a systematic literature search to support an international treat-to-target recommendation in spondyloarthritis.

BACKGROUND: Current recommendations for the management of axial spondyloarthritis (SpA) and psoriatic arthritis are to monitor disease activity and adjust therapy accordingly. However, treatment targets and timeframes of change have not been defined. An international expert panel has been convened to develop 'treat-to-target' recommendations, based on published evidence and expert opinion. OBJECTIVE: To review evidence on targeted treatment for axial and peripheral SpA, as well as for psoriatic skin disease. METHODS: We performed a systematic literature search covering Medline, Embase and Cochrane, conference abstracts and studies in http://www.clinicaltrials.gov. RESULTS: Randomised comparisons of targeted versus routine treatment are lacking. Some studies implemented treatment targets before escalating therapy: in ankylosing spondylitis, most trials used a decrease in Bath Ankylosing Spondylitis Disease Activity Index; in psoriatic arthritis, protocols primarily considered a reduction in swollen and tender joints; in psoriasis, the Modified Psoriasis Severity Score and the Psoriasis Area and Severity Index were used. Complementary evidence correlating these factors with function and radiographic damage at follow-up is sparse and equivocal. CONCLUSIONS: There is a need for randomised trials that investigate the value of treat-to-target recommendations in SpA and psoriasis. Several trials have used thresholds of disease activity measures to guide treatment decisions. However, evidence on the effect of these data on long-term outcome is scarce. The search data informed the expert committee regarding the formulation of recommendations and a research agenda.

New developments in our understanding of psoriatic arthritis and their impact on the diagnosis and clinical management of the disease.

Psoriatic arthritis (PsA) is a spondyloarthritis with a comorbid association with psoriasis. Without appropriate treatment it can be progressive, severe, deforming and destructive. It has long been recognized that subsets of PsA patients exist, characterized by different patterns of joint involvement. Associations between development of PsA and certain human leukocyte antigens (HLA) have been established. Evidence now suggests that progression of PsA is also genetically determined. The presence of one allele (HLA-B*27) has been associated with a distinct phenotype characterized by early joint involvement, whereas development of musculoskeletal symptoms is much slower in patients with another allele, C*06. Dermatologists need to consider what these differences in genotypes and phenotypes mean for clinical practice. Delay in the diagnosis of PsA is a significant contributor to poor patient outcomes, but there is evidence that PsA is underdiagnosed among psoriasis patients attending dermatology clinics. Dermatologists need to identify PsA symptoms among their psoriasis patients and refer for rheumatological assessment where appropriate. Treatment should address all aspects of the disease, including skin, nail and joint symptoms as well as physical functioning and quality of life. The existence of distinct phenotypic and genetic PsA subsets means dermatologists need to consider which drugs are likely to be most efficacious in which patient populations. Stratification of PsA according to susceptibility genes may in future help identify patients requiring more aggressive treatment to prevent progression. Biologic therapies show efficacy in PsA, but the patient populations of clinical trials are not always representative of patients treated with biologics in clinical practice.

Protocol for evaluating the E3 ligase activity of BRCA1-BARD1 and its variants by nucleosomal histone ubiquitylation.

The tumor suppressor breast cancer 1 (BRCA1) complexed with BRCA1-associated RING domain 1 (BARD1), a RING-type E3 ligase, facilitates the attachment of ubiquitin onto the substrate protein. Here, we present a protocol for evaluating the E3 ligase activity of BRCA1-BARD1 and its variants by nucleosomal histone ubiquitylation. We describe steps for isolating 147 bp Widom 601 DNA and assembling nucleosome core particles (NCPs). We then detail procedures for the in vitro ubiquitylation of nucleosome histone H2A by BRCA1-BARD1 and its variants. For complete details on the use and execution of this protocol, please refer to Wang et al.1.

Evaluation of round window accessibility to cochlear implant insertion.

Emphasis on hearing preservation has led to recognition of the round window membrane (RWM) as a portal for the cochlear implant electrode array. The St Thomas' Hospital (STH) classification was devised to evaluate the accessibility of RWM electrode insertion. The objectives of this study were: (1) to prospectively evaluate the STH classification in selecting the appropriate cochlear insertion route in "RWM-intentioned" cases, and (2) to ascertain if RWM accessibility differs from adults to children. This was a prospective cohort study of consecutive patients (adult and paediatric) undergoing cochlear implantation at a specialist auditory implant centre. Visibility of the RWM was graded according to the STH classification after an "optimal" posterior tympanotomy had been performed and any overhang of the bony round window niche removed without breaching the RWM. Most adult (89 %) and paediatric (78 %) cases had more than 50 % of the RWM exposed (Types I and IIa). Cases having less than 50 % of RWM exposed (Types IIb) or none exposed (Type III) were twice as common in children (p = 0.004). 96 % of Type I and 63 % of Type IIa cases underwent RWM insertion through a membranous cochleostomy. 71 % of Type IIb necessitated an extended membranous cochleostomy. All Type III cases required a conventional bony cochleostomy. When more than 50 % of RWM was visible (Types I and IIa), 88 % underwent a membranous cochleostomy. For "RWM-intentioned" cases, the STH classification can be a sensible method of relating RWM visibility/accessibility to the optimal route for insertion. This study also demonstrates that RWM insertion is more challenging in children.

European multi-centre study of the Nucleus Hybrid L24 cochlear implant.

OBJECTIVES: To investigate the preservation of residual hearing in subjects who received the Nucleus Hybrid L24 cochlear implant. To investigate the performance benefits up to one year post-implantation in terms of speech recognition, sound quality, and quality of life. DESIGN: Prospective, with sequential enrolment and within-subject comparisons. Post-operative performance using a Freedom Hybrid sound processor was compared with that of pre-operative hearing aids. STUDY SAMPLE: Sixty-six adult hearing-impaired subjects with bilateral severe-to-profound high frequency hearing loss. RESULTS: Group median increase in air-conduction thresholds in the implanted ear for test frequencies 125-1000 Hz was < 15 dB across the population; both immediately and one year post-operatively. Eighty-eight percent of subjects used the Hybrid processor at one year post-op. Sixty-five percent of subjects had significant gain in speech recognition in quiet, and 73% in noise (≥ 20 percentage points/2 dB SNR). Mean SSQ subscale scores were significantly improved (+ 1.2, + 1.3, + 1.8 points, p < 0.001), as was mean HUI3 score (+ 0.117, p < 0.01). Combining residual hearing with CI gave 22-26 %age points mean benefit in speech recognition scores over CI alone (p < 0.01). CONCLUSIONS: Useful residual hearing was conserved in 88% of subjects. Speech perception was significantly improved over preoperative hearing aids, as was sound quality and quality of life.

European League Against Rheumatism recommendations for the management of psoriatic arthritis with pharmacological therapies.

BACKGROUND: Psoriatic arthritis (PsA) is a clinically heterogeneous disease. Clear consensual treatment guidance focused on the musculoskeletal manifestations of PsA would be advantageous. The authors present European League Against Rheumatism (EULAR) recommendations for the treatment of PsA with systemic or local (non-topical) symptomatic and disease-modifying antirheumatic drugs (DMARD). METHODS: The recommendations are based on evidence from systematic literature reviews performed for non-steroidal anti-inflammatory drugs (NSAID), glucocorticoids, synthetic DMARD and biological DMARD. This evidence was discussed, summarised and recommendations were formulated by a task force comprising 35 representatives, and providing levels of evidence, strength of recommendations and levels of agreement. RESULTS: Ten recommendations were developed for treatment from NSAID through synthetic DMARD to biological agents, accounting for articular and extra-articular manifestations of PsA. Five overarching principles and a research agenda were defined. CONCLUSION: These recommendations are intended to provide rheumatologists, patients and other stakeholders with a consensus on the pharmacological treatment of PsA and strategies to reach optimal outcomes, based on combining evidence and expert opinion. The research agenda informs directions within EULAR and other communities interested in PsA.

Discontinuity of the incudo-stapedial joint within a fully aerated middle ear and mastoid on computed tomography: A clinico-radiological study of its aetiology and clinical consequence.

AIM: To investigate the aetiology and clinical consequences of incudo-stapedial (IS) discontinuity when it is demonstrated on computed tomography (CT) within a fully aerated middle ear and mastoid. METHODS AND MATERIALS: Patients with CT evidence of IS discontinuity within a fully aerated middle ear and mastoid were prospectively identified. Clinical history, otoscopic findings, audiometry, and CT data were evaluated. Predefined criteria were used to determine the likely aetiology of IS discontinuity, whether it was diagnosed prior to the CT study, and the clinical consequences in terms of degree of conductive hearing loss and requirement for surgical correction. The range of CT appearances was evaluated. RESULTS: The IS discontinuity in 34/36 ears was felt to be due to incus erosion secondary to chronic otitis, on the basis of clinical history and otoscopic findings. The IS discontinuity was rarely evident prior to CT with long-process deficiency being identified in only 5/36 cases. The mean air bone gap was only 22.5 dB. The ossicular defect was surgically addressed in only four cases. The incus deficiency was confined to the lower-third on CT in 19/36 cases. CONCLUSION: When IS discontinuity is demonstrated within a fully aerated middle ear and mastoid, the most likely aetiology is of acquired incus erosion due to chronic otitis media. The IS discontinuity on CT is usually not evident otoscopically. It usually results in only mild conductive hearing loss and the ossicular discontinuity was rarely surgically addressed in the present series.

Joint tenderness and swelling in biologic-treated inflammatory arthritis patients - a tricky trade off?

OBJECTIVE: To compare the pattern of joint responses in patients with rheumatoid arthritis and psoriatic arthritis treated with TNF inhibitor (TNFi) therapy. METHODS: A total of 182 PsA/Rheumatoid arthritis (RA) patients attending the rheumatology unit of a tertiary referral centre in Ireland were recruited and prospectively followed up by the attendant rheumatologists. Clinical progress of the patients was noted at baseline and 6 months after starting TNFi therapy. RESULTS: A total of 114 RA and 68 PsA patients were assessed; 20% of the patients had one of either tender joints or swollen joints after 6 months of therapy. Rheumatoid arthritis patients had a significantly higher proportion of non-tender swollen joints compared with PsA patients, whereas PsA patients had a higher proportion of tender non-swollen joints (p < 0.05). CONCLUSION: Residual joint swelling was found more commonly in RA patients than in PsA patients following TNFi therapy, whereas residual tender joints occurred more frequently in PsA; this may reflect enthesiopathy or periostitis.

High-Efficiency Plasmid DNA Transformation in Yeast.

Transformation of DNA into cells of the budding yeast Saccharomyces cerevisiae and other industrially important yeasts is most commonly performed using chemical-based methods. Current protocols typically involve exposure of the cells to lithium ions in a solution containing the crowding agent polyethylene glycol (PEG), often in conjunction with other reagents such as dimethyl sulfoxide (DMSO) that promote destabilization of the cell wall and/or cell envelope. Recent work has demonstrated that it is possible to achieve high transformation efficiencies with early stationary phase cells, i.e., small overnight liquid cell cultures, using methods that are rapid and readily scalable for high-throughput projects. Herein, we describe carrier DNAs, chemical reagents, and cell growth media that permit transformation of yeast cells with either plasmids or linear DNA fragments with high efficiency.

A systematic review of free tissue transfer in the management of non-traumatic lower extremity wounds in patients with diabetes.

OBJECTIVES: Wounds of the lower limb in patients with diabetes are frequently difficult to heal. Some wounds fail to heal despite optimal medical and surgical care. This review examines the evidence for whether free tissue transfer techniques may reduce the requirement of amputation in these patients. DESIGN: A systematic review. MATERIALS & METHODS: Pubmed, Embase, AMED, SCOPUS and CINAHL and Cochrane Library were searched for all articles on free tissue transfer in lower limb wounds in patients with diabetes (September 2010). Current experience, indications and outcomes were analysed. RESULTS: 528 patients from 18 studies were included in the systematic review. 66% of patients had concomitant revascularisation with bypass surgery. 63% of flaps were muscle based, 35% fasciocutaneous and 1.7% omental. Pooled in-hospital mortality rate was 4.4%, flap survival was 92% and limb salvage rate of 83.4% over a 28 months average follow-up time. CONCLUSIONS: In conclusion free tissue transfer achieves successful wound healing in selected patients with diabetes and difficult to heal wounds that would have required amputation. Pre-operative optimisation of vascular supply and eradication of infection is key to success. Objective wound assessment scores and a clear multidisciplinary team (MDT) approach would improve patient care.