The application of antimicrobial stewardship knowledge to nursing practice: A national survey of United Kingdom pre-registration nursing students.

AIM: To assess student nurses understanding and skills in the application of antimicrobial stewardship knowledge to practice. DESIGN: Quantitative. METHODS: Cross-sectional survey. RESULTS: Five hundred and twenty three student nurses responded across 23 UK universities. Although students felt prepared in competencies in infection prevention and control, patient-centred care and interprofessional collaborative practice, they felt less prepared in competencies in which microbiological knowledge, prescribing and its effect on antimicrobial stewardship is required. Problem-based learning, activities in the clinical setting and face-to-face teaching were identified as the preferred modes of education delivery. Those who had shared antimicrobial stewardship teaching with students from other professions reported the benefits to include a broader understanding of antimicrobial stewardship, an understanding of the roles of others in antimicrobial stewardship and improved interprofessional working. CONCLUSION: There are gaps in student nurses' knowledge of the basic sciences associated with the antimicrobial stewardship activities in which nurses are involved, and a need to strengthen knowledge in pre-registration nurse education programmes pertaining to antimicrobial management, specifically microbiology and antimicrobial regimes and effects on antimicrobial stewardship. Infection prevention and control, patient-centred care and interprofessional collaborative practice are areas of antimicrobial stewardship in which student nurses feel prepared. Interprofessional education would help nurses and other members of the antimicrobial stewardship team clarify the role nurses can play in antimicrobial stewardship and therefore maximize their contribution to antimicrobial stewardship and antimicrobial management. IMPLICATIONS FOR THE PROFESSION: There is a need to strengthen knowledge from the basic sciences, specifically pertaining to antimicrobial management, in pre-registration nurse education programmes. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution. IMPACT: What Problem Did the Study Address? Nurses must protect health through understanding and applying antimicrobial stewardship knowledge and skills (Nursing and Midwifery Council 2018); however, there is no research available that has investigated nurses understanding and skills of the basic sciences associated with the antimicrobial stewardship activities in which they are involved. What Were the Main Findings? There are gaps in student nurses' knowledge of the basic sciences (specifically microbiology and prescribing) associated with the antimicrobial stewardship activities in which nurses are involved. Problem-based learning, and activities in the clinical setting, were reported as useful teaching methods, whereas online learning, was seen as less useful. Where and on Whom Will the Research Have an Impact? Pre-registration nurse education programmes. REPORTING METHOD: The relevant reporting method has been adhered to, that is, STROBE.

First-Line Ipatasertib, Atezolizumab, and Taxane Triplet for Metastatic Triple-Negative Breast Cancer: Clinical and Biomarker Results.

PURPOSE: To evaluate a triplet regimen combining immune checkpoint blockade, AKT pathway inhibition, and (nab-) paclitaxel as first-line therapy for locally advanced/metastatic triple-negative breast cancer (mTNBC). PATIENTS AND METHODS: The single-arm CO40151 phase Ib study (NCT03800836), the single-arm signal-seeking cohort of IPATunity130 (NCT03337724), and the randomized phase III IPATunity170 trial (NCT04177108) enrolled patients with previously untreated mTNBC. Triplet therapy comprised intravenous atezolizumab 840 mg (days 1 and 15), oral ipatasertib 400 mg/day (days 1-21), and intravenous paclitaxel 80 mg/m2 (or nab-paclitaxel 100 mg/m2; days 1, 8, and 15) every 28 days. Exploratory translational research aimed to elucidate mechanisms and molecular markers of sensitivity and resistance. RESULTS: Among 317 patients treated with the triplet, efficacy ranged across studies as follows: median progression-free survival (PFS) 5.4 to 7.4 months, objective response rate 44% to 63%, median duration of response 5.6 to 11.1 months, and median overall survival 15.7 to 28.3 months. The safety profile was consistent with the known toxicities of each agent. Grade ≥3 adverse events were more frequent with the triplet than with doublets or single-agent paclitaxel. Patients with PFS >10 months were characterized by NF1, CCND3, and PIK3CA alterations and increased immune pathway activity. PFS <5 months was associated with CDKN2A/CDKN2B/MTAP alterations and lower predicted phosphorylated AKT-S473 levels. CONCLUSIONS: In patients with mTNBC receiving an ipatasertib/atezolizumab/taxane triplet regimen, molecular characteristics may identify those with particularly favorable or unfavorable outcomes, potentially guiding future research efforts.

Cytochrome P450-2D6 activity in people with codeine use disorder.

Compound-analgesics containing codeine (CACC) have been a common source of codeine for people seeking opioid replacement therapy (ORT) for codeine use disorder (CUD). Our previous work demonstrated no relationship between pre-treatment CACC and ORT buprenorphine doses; we hypothesised that CYP2D6 activity would partially account for this disconnection. One hundred six participants with CUD were compared to a published population sample of 5408 Australian patients. Mean age of participants with CUD at treatment entry was 35 years, with mean 6.1 years duration of CUD. Mean codeine dose was 660 mg/day (range 40-2700 mg). Mean calculated CYP2D6 activity scores were significantly higher in the codeine group (CUD 1.65 + 0.63 vs. Gen pop 1.39 + 0.65, Wilcoxon W = 347,001, p < 0.001). Pre-treatment CACC dose weakly predicted sublingual buprenorphine doses overall; there was a stronger relationship within ultrarapid metabolisers. While normal and ultrarapid metabolisers of codeine were more likely to have a diagnosis of CUD, poor or intermediate CYP2D6 metaboliser status may protect against CUD.

A transcriptional network required for bradyzoite development in Toxoplasma gondii is dispensable for recrudescent disease.

Identification of regulators of Toxoplasma gondii bradyzoite development and cyst formation is the most direct way to address the importance of parasite development in long-term persistence and reactivation of this parasite. Here we show that a T. gondii gene (named Regulator of Cystogenesis 1; ROCY1) is sufficient for T. gondii bradyzoite formation in vitro and in vivo. ROCY1 encodes an RNA binding protein that has a preference for 3' regulatory regions of hundreds of T. gondii transcripts, and its RNA-binding domains are required to mediate bradyzoite development. Female mice infected with ΔROCY1 parasites have reduced (>90%) cyst burden. While viable parasites can be cultivated from brain tissue for up to 6 months post-infection, chronic brain-resident ΔROCY1 parasites have reduced oral infectivity compared to wild type. Despite clear defects in bradyzoite formation and oral infectivity, ΔROCY1 parasites were able to reactivate with similar timing and magnitude as wild type parasites for up to 5 months post-infection. Therefore while ROCY1 is a critical regulator of the bradyzoite developmental pathway, it is not required for parasite reactivation, raising new questions about the persisting life stage responsible for causing recrudescent disease.

Nonviral In Vivo Delivery of CRISPR-Cas9 Using Protein-Agnostic, High-Loading Porous Silicon and Polymer Nanoparticles.

The complexity of CRISPR machinery is a challenge to its application for nonviral in vivo therapeutic gene editing. Here, we demonstrate that proteins, regardless of size or charge, efficiently load into porous silicon nanoparticles (PSiNPs). Optimizing the loading strategy yields formulations that are ultrahigh loading─>40% cargo by volume─and highly active. Further tuning of a polymeric coating on the loaded PSiNPs yields nanocomposites that achieve colloidal stability under cryopreservation, endosome escape, and gene editing efficiencies twice that of the commercial standard Lipofectamine CRISPRMAX. In a mouse model of arthritis, PSiNPs edit cells in both the cartilage and synovium of knee joints, and achieve 60% reduction in expression of the therapeutically relevant MMP13 gene. Administered intramuscularly, they are active over a broad dose range, with the highest tested dose yielding nearly 100% muscle fiber editing at the injection site. The nanocomposite PSiNPs are also amenable to systemic delivery. Administered intravenously in a model that mimics muscular dystrophy, they edit sites of inflamed muscle. Collectively, the results demonstrate that the PSiNP nanocomposites are a versatile system that can achieve high loading of diverse cargoes and can be applied for gene editing in both local and systemic delivery applications.

The Role of the Outpatient Occupational Therapist Treating Patients With Small Burns: A Retrospective Audit of Practice.

Current Australian burn care practice guidelines recommend therapies prescribed for burn injuries, irrespective of burn size. These guidelines have been informed by research related to large burns and associated treatment burden. This article describes the clinical management of small burns by occupational therapists at a large tertiary facility in Australia. A retrospective clinical chart audit was conducted for the 12-month period from January to December 2019. Participants were eligible if they had sustained a burn of 1% TBSA or less. Eligibility criteria were met for 454 patients, reflecting 77% of new outpatients in 2019. Of these, 247 or 54% of patients saw an occupational therapist. Noninvasive therapies such as scar massage, compression, silicone and taping were prescribed for 35%, 32.6%, 22.6%, and 5.9% of patients, respectively. Occupational therapist involvement was more likely postsurgical intervention (84.5%). The data presented contribute to limited research available for the management of small burns. Findings reflect use of traditional forms of therapies for small scar management; however, there appeared little use of alternative therapies, such as tapes, which may be beneficial. This study highlights the potential need for current standard practice guidelines be nuanced according burn surface area.

Ipatasertib plus paclitaxel for PIK3CA/AKT1/PTEN-altered hormone receptor-positive HER2-negative advanced breast cancer: primary results from cohort B of the IPATunity130 randomized phase 3 trial.

PURPOSE: PI3K/AKT pathway alterations are frequent in hormone receptor-positive (HR+) breast cancers. IPATunity130 Cohort B investigated ipatasertib-paclitaxel in PI3K pathway-mutant HR+ unresectable locally advanced/metastatic breast cancer (aBC). METHODS: Cohort B of the randomized, double-blind, placebo-controlled, phase 3 IPATunity130 trial enrolled patients with HR+ HER2-negative PIK3CA/AKT1/PTEN-altered measurable aBC who were considered inappropriate for endocrine-based therapy (demonstrated insensitivity to endocrine therapy or visceral crisis) and were candidates for taxane monotherapy. Patients with prior chemotherapy for aBC or relapse < 1 year since (neo)adjuvant chemotherapy were ineligible. Patients were randomized 2:1 to ipatasertib (400 mg, days 1-21) or placebo, plus paclitaxel (80 mg/m2, days 1, 8, 15), every 28 days until disease progression or unacceptable toxicity. The primary endpoint was investigator-assessed progression-free survival (PFS). RESULTS: Overall, 146 patients were randomized to ipatasertib-paclitaxel and 76 to placebo-paclitaxel. In both arms, median investigator-assessed PFS was 9.3 months (hazard ratio, 1.00, 95% CI 0.71-1.40) and the objective response rate was 47%. Median paclitaxel duration was 6.9 versus 8.8 months in the ipatasertib-paclitaxel versus placebo-paclitaxel arms, respectively; median ipatasertib/placebo duration was 8.0 versus 9.1 months, respectively. The most common grade ≥ 3 adverse events were diarrhea (12% with ipatasertib-paclitaxel vs 1% with placebo-paclitaxel), neutrophil count decreased (9% vs 7%), neutropenia (8% vs 9%), peripheral neuropathy (7% vs 3%), peripheral sensory neuropathy (3% vs 5%) and hypertension (1% vs 5%). CONCLUSION: Adding ipatasertib to paclitaxel did not improve efficacy in PIK3CA/AKT1/PTEN-altered HR+ HER2-negative aBC. The ipatasertib-paclitaxel safety profile was consistent with each agent's known adverse effects. Trial registration NCT03337724.

Final results of the double-blind placebo-controlled randomized phase 2 LOTUS trial of first-line ipatasertib plus paclitaxel for inoperable locally advanced/metastatic triple-negative breast cancer.

PURPOSE: In LOTUS (NCT02162719), adding the oral AKT inhibitor ipatasertib to first-line paclitaxel for locally advanced/metastatic triple-negative breast cancer (aTNBC) improved progression-free survival (PFS; primary endpoint), with an enhanced effect in patients with PIK3CA/AKT1/PTEN-altered tumors (FoundationOne next-generation sequencing [NGS] assay). We report final overall survival (OS) results. METHODS: Eligible patients had measurable previously untreated aTNBC. Patients were stratified by prior (neo)adjuvant therapy, chemotherapy-free interval, and tumor immunohistochemistry PTEN status, and were randomized 1:1 to paclitaxel 80 mg/m2 (days 1, 8, 15) plus ipatasertib 400 mg or placebo (days 1-21) every 28 days until disease progression or unacceptable toxicity. OS (intent-to-treat [ITT], immunohistochemistry PTEN-low, and PI3K/AKT pathway-activated [NGS PIK3CA/AKT1/PTEN-altered] populations) was a secondary endpoint. RESULTS: Median follow-up was 19.0 versus 16.0 months in the ipatasertib-paclitaxel versus placebo-paclitaxel arms, respectively. In the ITT population (n = 124), median OS was numerically longer with ipatasertib-paclitaxel than placebo-paclitaxel (hazard ratio 0.80, 95% CI 0.50-1.28; median 25.8 vs 16.9 months, respectively; 1-year OS 83% vs 68%). Likewise, median OS favored ipatasertib-paclitaxel in the PTEN-low (n = 48; 23.1 vs 15.8 months; hazard ratio 0.83) and PIK3CA/AKT1/PTEN-altered (n = 42; 25.8 vs 22.1 months; hazard ratio 1.13) subgroups. The ipatasertib-paclitaxel safety profile was unchanged. CONCLUSIONS: Final OS results show a numerical trend favoring ipatasertib-paclitaxel and median OS exceeding 2 years with ipatasertib-paclitaxel. Overall, results are consistent with the reported PFS benefit; interpretation within biomarker-defined subgroups is complicated by small sample sizes and TNBC heterogeneity.

Use of tape for the management of hypertrophic scar development: A comprehensive review.

INTRODUCTION: Tapes have been used to aid fresh wound closure. For hypertrophic scars, the use of tapes as a therapy to reduce the mechanical forces that stimulate excessive and long-term scarring is yet to be evaluated. The aim of this comprehensive review was to explore the current clinical application of tapes, as a minimally invasive option, as purposed specifically for the management of hypertrophic scarring, regardless of scar causation. METHOD: Databases were searched using MeSH terms including one identifier for hypertrophic scar and one for the intervention of taping. Studies included the following: patients who received tape for a minimum of 12 weeks as a method of wound closure specifically for the purpose of scar prevention; those who received tape as a method of scar management after scar formation; reported outcomes addressing subjective and/or objective scar appearance; and were available in English. RESULTS: With respect to non-stretch tapes, their use for the prevention of linear surgical scarring is evident in reducing scar characteristics of height, colour and itch. Statistically significant results were found in median scar width, reduction in procedure times and overall scar rating. Tapes were predominately applied by participants themselves, and incidence of irritation was infrequently reported. After 12 months, significance with respect to scar pain, itch, thickness and overall scar elevation was reported in one study investigating paper tape. Two papers reported the use of high stretch tapes; however, subjective results limited formal analysis. Although the use of taping for abnormal hypertrophic scar management is in its infancy, emerging research indicates tapes with an element of stretch may have a positive impact. CONCLUSIONS: Non-stretch tapes, for the prevention of linear surgical scarring, are effective in reducing scar characteristics of height, colour and itch. Paper tapes have shown effectiveness when applied during wound remodelling or even on mature scarring, with reported subjective changes in scar colour, thickness and pliability. Preliminary evidence of the benefits of high-stretch, elasticised tapes for scar management in the remodelling phase of wound healing have also been reported. LAY SUMMARY: Patients are often concerned about unsightly scars that form on their bodies after trauma, especially burn injuries. These scars can be thick, red and raised on the skin, and can impact on the patient's quality of life. For some scars, the process of skin thickening continues for up to two years after an injury.Unfortunately, scar formation is a part of the body's healing process, whereby there is a constant pull or tension under and along the skin's surface. The use of simple tapes, such as microporetm, to help with wound closure are sometimes used as a therapy to reduce the tension on the skin's surface when a wound is healing to minimise scar formation. However, the effectiveness of taping has not been proven. This paper looks at the available evidence to support the use of taping to reduce scar features of height, thickness and colour. Initial evidence of mixed levels, suggests some benefits of tapes for scar management and show preliminary efficacy for reduction of scar height, thickness and colour. More research is required to determine the direct impact, comparison to other treatments available and patient viewpoint for this therapy.

Patient Voices Network: Bringing Breast Cancer Awareness and Action into Underserved Communities.

BACKGROUND/PURPOSE: African American women are diagnosed with breast cancer at later stages and have higher mortality rates than white women. The Patient Voices Network (PVN), a community group whose vision is "a community of educated and involved patients working hand in hand with physicians in making decisions about their own health care," conceived of and implemented a walk to raise awareness of breast cancer and link women to screening resources in a low-income, urban community OBJECTIVES: To describe the planning and implementation of the Concerned About You: Breast Cancer Awareness Walk & Wellness Event and its impact on an academic community partnership. METHODS: A narrative approach was used. Meeting minutes and event planning notes were reviewed. Community participation rates and participant satisfaction were tracked using registration records and a survey administered at the event. RESULTS: 328 community members registered and 194 attended. Responses to a satisfaction survey indicated community buy-in and interest in future events. Two women were screened at the event and 78 were screened at a follow-up opportunity at their primary care practices. The process was driven by participatory guidelines and laid the foundation for future activities. CONCLUSIONS: Community input addressed the need for screening mammography in an underserved community. The partnership approach featured complementary strengths of both patients and University staff, fostered skill building and co-learning, and ultimately strengthened our partnership. A partnered approach may be effective in engaging hard-to-reach populations to address health disparities.

Acute pulmonary oedema.

Acute pulmonary oedema is a distressing and life-threatening illness that is associated with a sudden onset of symptoms. For the best possible patient outcomes, it is essential that nurses in all clinical areas are equipped to accurately recognise, assess and manage patients with acute pulmonary oedema. This article outlines the pathophysiology of acute cardiogenic and non-cardiogenic pulmonary oedema, and suggests a systematic approach to the recognition and management of its most serious manifestations. Long-term care and symptom recognition are discussed and suggestions for ongoing patient self-management are provided.

GeneiASE: Detection of condition-dependent and static allele-specific expression from RNA-seq data without haplotype information.

Allele-specific expression (ASE) is the imbalance in transcription between maternal and paternal alleles at a locus and can be probed in single individuals using massively parallel DNA sequencing technology. Assessing ASE within a single sample provides a static picture of the ASE, but the magnitude of ASE for a given transcript may vary between different biological conditions in an individual. Such condition-dependent ASE could indicate a genetic variation with a functional role in the phenotypic difference. We investigated ASE through RNA-sequencing of primary white blood cells from eight human individuals before and after the controlled induction of an inflammatory response, and detected condition-dependent and static ASE at 211 and 13021 variants, respectively. We developed a method, GeneiASE, to detect genes exhibiting static or condition-dependent ASE in single individuals. GeneiASE performed consistently over a range of read depths and ASE effect sizes, and did not require phasing of variants to estimate haplotypes. We observed condition-dependent ASE related to the inflammatory response in 19 genes, and static ASE in 1389 genes. Allele-specific expression was confirmed by validation of variants through real-time quantitative RT-PCR, with RNA-seq and RT-PCR ASE effect-size correlations r = 0.67 and r = 0.94 for static and condition-dependent ASE, respectively.

Chronic kidney disease (CKD) treatment burden among low-income primary care patients.

OBJECTIVE: This study explored the self-management strategies and treatment burden experienced by low-income US primary care patients with chronic kidney disease. METHODS: Semi-structured interviews were conducted with 34 patients from two primary care practices on Buffalo's East Side, a low-income community. Qualitative analysis was undertaken using an inductive thematic content analysis approach. We applied normalization process theory (NPT) to the concept of treatment burden to interpret and categorize our findings. RESULTS: The sample was predominantly African-American (79%) and female (59%). Most patients (79%) had a diagnosis of stage 3 CKD. Four major themes were identified corresponding to NPT and treatment burden: (1) coherence--making sense of CKD; (2) cognitive participation--enlisting support and organizing personal resources; (3) collective action--self-management work; and (4) reflexive monitoring--further refining chronic illness self-care in the context of CKD. For each component, we identified barriers hindering patients' ability to accomplish the necessary tasks. CONCLUSIONS: Our findings highlight the substantial treatment burden faced by inner-city primary care patients self-managing CKD in combination with other chronic illnesses. Health care providers' awareness of treatment burden can inform the development of person-centered care plans that can help patients to better manage their chronic illnesses.

Perceived cancer risk and risk attributions among African-American residents of a low-income, predominantly African-American neighborhood.

OBJECTIVE: In some national surveys, African-Americans have had lower scores on perceived cancer risk items than whites. Our goals were to confirm low perceptions of cancer risk in an African-American community sample and explore participants' attributions for their perceived cancer risk. DESIGN: Data were from three cross-sectional surveys. We report levels of perceived absolute and comparative cancer risk in a community sample of African-Americans (N = 88), and African-Americans (Ns = 655, 428) and whites (Ns = 5262, 1679) from two nationally representative Health Information National Trends Surveys (HINTS). We analyzed the content of spontaneously-provided explanations for perceived risk from the community sample. RESULTS: Perceived absolute and comparative cancer risk were lower in the community and national samples of African-Americans than in the national sample of whites. Participants' spontaneous attributions for low or lower than average risk included not having family history or behavioral risk factors, classes of attributions noted elsewhere in the literature. However, participants also explained that they wanted to avoid wishing cancer on themselves (positive affirmations) and hoped their risk was low (wishful thinking), responses rarely reported for majority-white samples. CONCLUSIONS: Results provide further evidence that cancer risk perceptions are lower among African-Americans than whites. Some participant explanations for low perceived risk (wishful thinking, affirmations) are inconsistent with behavioral scientists' assumptions about perceived risk questions. Results reveal a need to expand cancer risk attribution typologies to increase applicability to diverse populations, and may indicate that perceived cancer risk questions have lower validity in African-American populations.

Increased long-term expression of pentraxin 3 in irradiated human arteries and veins compared to internal controls from free tissue transfers.

BACKGROUND: Clinical studies have shown that radiotherapy increases the risk of cardiovascular disease at irradiated sites years after exposure. However, there is a lack of biological explanations in humans. We therefore examined human blood vessels exposed to radiotherapy and studied C-reactive protein (CRP) and pentraxin 3 (PTX3), a new marker for adverse cardiovascular outcome dependent on TNF- alpha (TNFα) or interleukin-1beta (IL-1ß) expression. METHODS: Pairs of irradiated and non-irradiated human conduit arteries and veins were harvested from the same patient during autologous free tissue transfer for cancer-reconstruction at a median time of 48 weeks after radiotherapy. Differential gene expression was studied using qRT-PCR, confirmed by immunohistochemistry and cellular origins determined by immunofluorescence. RESULTS: Gene expression in irradiated arteries compared to non-irradiated showed a consistent up-regulation of PTX3 in all patients and in a majority of veins (p < 0.001). Both TNFα and IL-1ß were increased in irradiated compared to non-irradiated arteries (p < 0.01) and IL-1ß correlated to the PTX3 expression (p = 0.017). Immunohistochemical and immunofluorescence staining confirmed an increased expression of PTX3 in endothelial cells, macrophages and smooth muscle cells. CONCLUSIONS: The sustained expression of PTX3 in arteries and veins tie biological evidence in humans to clinical studies and encourage further exploration of innate immunity in the pathogenesis of a radiation-induced vasculopathy.

Inhibition of extracellular signal-regulated kinase 1/2 signaling has beneficial effects on skeletal muscle in a mouse model of Emery-Dreifuss muscular dystrophy caused by lamin A/C gene mutation.

BACKGROUND: Autosomal Emery-Dreifuss muscular dystrophy is caused by mutations in the lamin A/C gene (LMNA) encoding A-type nuclear lamins, intermediate filament proteins of the nuclear envelope. Classically, the disease manifests as scapulo-humeroperoneal muscle wasting and weakness, early joint contractures and dilated cardiomyopathy with conduction block; however, move variable skeletal muscle involvement can be present. Previously, we demonstrated increased activity of extracellular signal-regulated kinase (ERK) 1/2 in hearts of LmnaH222P/H222P mice, a model of autosomal Emery-Dreifuss muscular dystrophy, and that blocking its activation improved cardiac function. We therefore examined the role of ERK1/2 activity in skeletal muscle pathology. METHODS: Sections of skeletal muscle from LmnaH222P/H222P mice were stained with hematoxylin and eosin and histological analysis performed using light microscopy. ERK1/2 activity was assessed in mouse tissue and cultured cells by immunoblotting and real-time polymerase chain reaction to measure expression of downstream target genes. LmnaH222P/H222P mice were treated with selumetinib, which blocks mitogen-activated protein kinase/extracellular signal-regulated kinase kinase 1/2 that activates ERK1/2, from 16 to 20 weeks of age to assess the effects of treatment on muscle histology, ERK1/2 activity and limb grip strength. RESULTS: We detected enhanced activation of ERK1/2 in skeletal muscle of LmnaH222P/H222P mice. Treatment with selumetinib ameliorated skeletal muscle histopathology and reduced serum creatine phosphokinase and aspartate aminotransferase activities. Selumetinib treatment also improved muscle function as assessed by in vivo grip strength testing. CONCLUSIONS: Our results show that ERK1/2 plays a role in the development of skeletal muscle pathology in LmnaH222/H222P mice. They further provide the first evidence that a small molecule drug may be beneficial for skeletal muscle in autosomal Emery-Dreifuss muscular dystrophy.

Innate immune activation by inhaled lipopolysaccharide, independent of oxidative stress, exacerbates silica-induced pulmonary fibrosis in mice.

Acute exacerbations of pulmonary fibrosis are characterized by rapid decrements in lung function. Environmental factors that may contribute to acute exacerbations remain poorly understood. We have previously demonstrated that exposure to inhaled lipopolysaccharide (LPS) induces expression of genes associated with fibrosis. To address whether exposure to LPS could exacerbate fibrosis, we exposed male C57BL/6 mice to crystalline silica, or vehicle, followed 28 days later by LPS or saline inhalation. We observed that mice receiving both silica and LPS had significantly more total inflammatory cells, more whole lung lavage MCP-1, MIP-2, KC and IL-1ß, more evidence of oxidative stress and more total lung hydroxyproline than mice receiving either LPS alone, or silica alone. Blocking oxidative stress with N-acetylcysteine attenuated whole lung inflammation but had no effect on total lung hydroxyproline. These observations suggest that exposure to innate immune stimuli, such as LPS in the environment, may exacerbate stable pulmonary fibrosis via mechanisms that are independent of inflammation and oxidative stress.

Combined chromatin and expression analysis reveals specific regulatory mechanisms within cytokine genes in the macrophage early immune response.

Macrophages play a critical role in innate immunity, and the expression of early response genes orchestrate much of the initial response of the immune system. Macrophages undergo extensive transcriptional reprogramming in response to inflammatory stimuli such as Lipopolysaccharide (LPS).To identify gene transcription regulation patterns involved in early innate immune responses, we used two genome-wide approaches--gene expression profiling and chromatin immunoprecipitation-sequencing (ChIP-seq) analysis. We examined the effect of 2 hrs LPS stimulation on early gene expression and its relation to chromatin remodeling (H3 acetylation; H3Ac) and promoter binding of Sp1 and RNA polymerase II phosphorylated at serine 5 (S5P RNAPII), which is a marker for transcriptional initiation. Our results indicate novel and alternative gene regulatory mechanisms for certain proinflammatory genes. We identified two groups of up-regulated inflammatory genes with respect to chromatin modification and promoter features. One group, including highly up-regulated genes such as tumor necrosis factor (TNF), was characterized by H3Ac, high CpG content and lack of TATA boxes. The second group, containing inflammatory mediators (interleukins and CCL chemokines), was up-regulated upon LPS stimulation despite lacking H3Ac in their annotated promoters, which were low in CpG content but did contain TATA boxes. Genome-wide analysis showed that few H3Ac peaks were unique to either +/-LPS condition. However, within these, an unpacking/expansion of already existing H3Ac peaks was observed upon LPS stimulation. In contrast, a significant proportion of S5P RNAPII peaks (approx 40%) was unique to either condition. Furthermore, data indicated a large portion of previously unannotated TSSs, particularly in LPS-stimulated macrophages, where only 28% of unique S5P RNAPII peaks overlap annotated promoters. The regulation of the inflammatory response appears to occur in a very specific manner at the chromatin level for specific genes and this study highlights the level of fine-tuning that occurs in the immune response.

Treatment with selumetinib preserves cardiac function and improves survival in cardiomyopathy caused by mutation in the lamin A/C gene.

AIMS: Mutations in A-type nuclear lamins gene, LMNA, lead to a dilated cardiomyopathy. We have reported abnormal activation of the extracellular signal-regulated kinase1/2 (ERK1/2) signalling in hearts from Lmna(H222P/H222P) mice, which develop dilated cardiomyopathy. We therefore determined whether an inhibitor of ERK1/2 signalling that has been investigated in clinical trials for cancer has the potential to be translated to humans with LMNA cardiomyopathy. METHODS AND RESULTS: To evaluate the relevance of this finding in mice to patients, we analysed the ERK1/2 signalling in heart tissue from human subjects with LMNA cardiomyopathy and showed that it was abnormally activated. To determine whether pharmacological inhibitors of the ERK1/2 signalling pathway could potentially be used to treat LMNA cardiomyopathy, we administered selumetinib to male Lmna(H222P/H222P) mice starting at 16 weeks of age, after they show signs of cardiac deterioration, up to 20 weeks of age. Selumetinib is an inhibitor of ERK1/2 signalling and has been given safely to human subjects in clinical trials for cancer. Systemic treatment with selumetinib inhibited cardiac ERK1/2 phosphorylation and blocked increased expression of RNAs encoding natriuretic peptide precursors and proteins involved in sarcomere architecture that occurred in placebo-treated mice. Echocardiography and histological analysis demonstrated that treatment increases cardiac fractional shortening, prevents myocardial fibrosis, and prolongs survival. Selumetinib treatment did not induce biochemical abnormalities suggestive of renal or hepatic toxicity. CONCLUSION: Our results suggest that selumetinib or other related inhibitors that have been safely administered to humans in clinical trials could potentially be used to treat LMNA cardiomyopathy.