Where traditional extinction estimates fall flat: using novel cophylogenetic methods to estimate extinction risk in platyhelminths.

Today parasites comprise a huge proportion of living biodiversity and play a major role in shaping community structure. Given their ecological significance, parasite extinctions could result in massive cascading effects across ecosystems. It is therefore crucial that we have a way of estimating their extinction risk. Attempts to do this have often relied on information about host extinction risk, without explicitly incorporating information about the parasites. However, assuming an identical risk may be misleading. Here, we apply a novel metric to estimate the cophylogenetic extinction rate, Ec, of parasites with their hosts. This metric incorporates information about the evolutionary history of parasites and hosts that can be estimated using event-based cophylogenetic methods. To explore this metric, we investigated the use of different cophylogenetic methods to inform the Ec rate, based on the analysis of polystome parasites and their anuran hosts. We show using both parsimony- and model-based approaches that different methods can have a large effect on extinction risk estimation. Further, we demonstrate that model-based approaches offer greater potential to provide insights into cophylogenetic history and extinction risk.

Delayed cardiac tamponade: A rare but life-threatening complication of catheter ablation.

Delayed cardiac tamponade (DCT) is a rare and life-threatening complication of catheter ablation performed as a treatment of atrial fibrillation, with few cases described in the medical literature. We present the case of a 57year-old man presenting with DCT 61days following a catheter ablation procedure. To the best of our knowledge, this is the most delayed case of cardiac tamponade (CT) following catheter ablation described in the literature. We also discuss the importance of point of care ultrasound (POCUS) in the diagnosis and treatment of CT. Emergency physicians must maintain a high index of suspicion in making the diagnosis of CT as patients may present with vague symptoms such as neck or back pain, shortness of breath, fatigue, dizziness, or altered mental status, often without chest pain. Common risk factors for CT include cancer, renal failure, pericarditis, cardiac surgery, myocardial rupture, trauma, and retrograde aortic dissection. In addition, although rare, both catheter ablation and use of anticoagulation carry risks of developing CT. A worldwide survey of medical centers performing catheter ablation found CT as a complication in less than 2% of cases [1]. Some proposed mechanisms of DCT include small pericardial hemorrhages following post-procedural anticoagulation or rupture of the sealed ablation-induced left atrial wall [2]. Clinical examination and electrocardiography may be helpful. However, the criterion standard for diagnosing CT is echocardiography [3].

One-week and 3-month outcomes after an emergency department visit for undifferentiated musculoskeletal low back pain.

STUDY OBJECTIVE: Nearly 3 million patients present to US emergency departments (EDs) annually with undifferentiated musculoskeletal low back pain. Little is known about short- and longer-term outcomes in this group. We seek to describe the pain and functional outcomes 1 week and 3 months after discharge in a sample of ED patients presenting with undifferentiated musculoskeletal low back pain. METHODS: We used a prospective observational descriptive cohort design, enrolling ED patients with a chief complaint of low back pain classified as musculoskeletal in origin by the ED attending physician. We defined low back pain as pain originating in the posterior back between the tips of the scapulae and upper buttocks and excluded any patient with a traumatic back injury occurring within the previous month. We interviewed patients in the ED and then by telephone follow-up 1 week and 3 months after ED discharge, using a scripted closed-question data collection instrument. Our primary outcome was functional limitation attributable to low back pain assessed with a validated scale. Secondary outcomes included pain and analgesic use during the 24 hours before each follow-up telephone call. RESULTS: During a 9-month period beginning in July 2009, we approached 894 patients, of whom 556 were enrolled. We obtained follow-up on 97% of our sample at 1 week and 92% at 3 months. One week after ED discharge, 70% (95% confidence interval [CI] 66% to 74%) of patients reported back pain-related functional impairment, 59% (95% CI 55% to 63%) reported moderate or severe low back pain, and 69% (95% CI 65% to 73%) reported analgesic use within the previous 24 hours. Three months after ED discharge, 48% (95% CI 44% to 52%) of patients reported functional impairment, 42% (95% CI 38% to 46%) reported moderate or severe pain, and 46% (95% CI 44% to 50%) reported analgesic use within the previous 24 hours. CONCLUSION: There is substantial short- and longer-term morbidity and ongoing analgesic use among patients who present to an ED with undifferentiated musculoskeletal low back pain.

Predicting 7-day and 3-month functional outcomes after an ED visit for acute nontraumatic low back pain.

BACKGROUND: Recent work has shown that two-thirds of patients report functional disability 1 week after an emergency department (ED) visit for nontraumatic musculoskeletal low back pain (LBP). Nearly half of these patients report functional disability 3 months later. Identifying high-risk predictors of functional disability at each of these 2 time points will allow emergency clinicians to provide individual patients with an evidence-based understanding of their risk of protracted symptoms. OBJECT: The aim of the present study was to determine whether 5 high-risk features previously identified in various primary care settings predict poor functional outcomes among patients in the ED. The hypothesized predictors are as follows: LBP-related functional disability at baseline, radicular signs, depression, a work-related injury, or a history of chronic or recurrent LBP before the index episode. METHODS: We conducted a prospective observational cohort study of patients in the ED with a chief complaint of nontraumatic LBP, which the ED attending physician classified as musculoskeletal. We interviewed patients in the ED before discharge and performed a baseline assessment of functional disability using the 24-item Roland-Morris questionnaire. We also trichotomized the patient's baseline history of LBP into chronic (defined as 30 straight days with continuous LBP or a history of acute exacerbations more frequently than once per week); episodic (acute exacerbations more frequently than once per year but less frequently than once per week), or rarely/never (less frequently than once per year or no history of LBP). We performed telephone follow-up 1 week and 3 months after ED discharge using a scripted closed-question data collection instrument. The primary outcome was any functional limitation attributable to LBP at 1 week and 3 months, defined as a score greater than zero on the Roland-Morris questionnaire. We used logistic regression, adjusted for age, sex, and educational level, to assess the independent association between functional disability and each of the 5 hypothesized predictors listed above. RESULTS: We approached 894 patients for participation and included 556. We obtained follow-up on 97% and 92% of our sample at 1 week and 3 months, respectively. Two of the 5 hypothesized variables predicted functional disability at both time points: higher baseline Roland-Morris score (odds ratio [OR], 4.3; 95% confidence interval [CI], 2.6-6.9) and chronic LBP (OR, 2.3; 95% CI, 1.1-4.8) were associated with 7-day functional disability. These same 2 variables predicted functional disability 3 months after ED discharge-higher baseline Roland-Morris score (OR, 2.3; 95% CI, 1.4-3.9) and chronic LBP (OR, 2.8; 95% CI, 1.5-5.2). The remaining 3 hypothesized predictors (depression, radicular signs, and on-the-job injury) did not predict functional outcome at either time point. CONCLUSIONS: Patients in the ED with worse baseline functional impairment and a history of chronic LBP are 2 to 4 times most likely to have poor short- and longer-term outcomes.

Metoclopramide for acute migraine: a dose-finding randomized clinical trial.

STUDY OBJECTIVE: Intravenous metoclopramide is effective as primary therapy for acute migraine, but the optimal dose of this medication is not yet known. The objective of this study is to compare the efficacy and safety of 3 different doses of intravenous metoclopramide for the treatment of acute migraine. METHODS: This was a randomized, double-blind, dose-finding study conducted on patients who presented to our emergency department (ED) meeting International Classification of Headache Disorders criteria for migraine without aura. We randomized patients to 10, 20, or 40 mg of intravenous metoclopramide. We coadministered diphenhydramine to all patients to prevent extrapyramidal adverse effects. The primary outcome was improvement in pain on an 11-point numeric rating scale at 1 hour. Secondary outcomes included sustained pain freedom at 48 hours and adverse effects. RESULTS: In this study, 356 patients were randomized. Baseline demographics and headache features were comparable among the groups. At 1 hour, those who received 10 mg of intravenous metoclopramide improved by a mean of 4.7 numeric rating scale points (95% confidence interval [CI] 4.2 to 5.2 points); those who received 20 mg improved by 4.9 points (95% CI 4.4 to 5.4 points), and those who received 40 mg improved by 5.3 points (95% CI 4.8 to 5.9 points). Rates of 48-hour sustained pain freedom in the 10-, 20-, and 40-mg groups were 16% (95% CI 10% to 24%), 20% (95% CI 14% to 28%), and 21% (95% CI 15% to 29%), respectively. The most commonly occurring adverse event was drowsiness, which impaired function in 17% (95% CI 13% to 21%) of the overall study population. Akathisia developed in 33 patients. Both drowsiness and akathisia were evenly distributed across the 3 arms of the study. One month later, no patient had developed tardive dyskinesia. CONCLUSION: Twenty milligrams or 40 mg of metoclopramide is no better for acute migraine than 10 mg of metoclopramide.

CLK2 Is an Oncogenic Kinase and Splicing Regulator in Breast Cancer.

Genetically activated kinases have been attractive therapeutic targets in cancer due to the relative ease of developing tumor-specific treatment strategies for them. To discover novel putative oncogenic kinases, we identified 26 genes commonly amplified and overexpressed in breast cancer and subjected them to a lentiviral shRNA cell viability screen in a panel of breast cancer cell lines. Here, we report that CLK2, a kinase that phosphorylates SR proteins involved in splicing, acts as an oncogene in breast cancer. Deregulated alternative splicing patterns are commonly observed in human cancers but the underlying mechanisms and functional relevance are still largely unknown. CLK2 is amplified and overexpressed in a significant fraction of breast tumors. Downregulation of CLK2 inhibits breast cancer growth in cell culture and in xenograft models and it enhances cell migration and invasion. Loss of CLK2 in luminal breast cancer cells leads to the upregulation of epithelial-to-mesenchymal transition (EMT)-related genes and a switch to mesenchymal splice variants of several genes, including ENAH (MENA). These results imply that therapeutic targeting of CLK2 may be used to modulate EMT splicing patterns and to inhibit breast tumor growth.

Derivation of an abbreviated instrument for use in emergency department low back pain research: the five-item Roland Morris Questionnaire.

OBJECTIVES: Low back pain (LBP) is a common reason for emergency department (ED) visits in the United States. Pain and functional outcomes after ED visits for LBP tend to be poor. ED-based clinical LBP research is hampered by complexity of available outcome instruments, which can be time-consuming to administer. The purpose of this investigation was to determine if a shorter version of the well-validated and commonly used Roland Morris Disability Questionnaire (RMDQ) would retain the original 24-item instrument's ability to assess functional outcomes accurately in ED patients with LBP. METHODS: The authors used deidentified data obtained from a prospective LBP cohort study, which enrolled 674 patients during index ED visits for LBP, and followed them by telephone 1 week and 3 months later. Five items were selected from the original 24 items of the RMDQ using regression techniques. Internal consistency of the abbreviated scale was measured using Cronbach's alpha. The strength of association between the five-item scale (RM5) and the parent scale was determined at baseline, 1 week, and 3 months. The association between change in the parent scale and change in the RM5 and the change in RM5 that was most closely associated with a minimum clinically significant difference on the RMDQ were also determined. RESULTS: The Cronbach's alpha for the RM5 was 0.88 (95% confidence interval [CI] = 0.87 to 0.89) at baseline, 0.96 (95% CI = 0.96 to 0.96) at 7 days, and 0.97 (95% CI = 0.97 to 0.97) at 3 months. The Pearson correlation coefficient for the RM5 versus the parent scale was 0.93 (R(2)  = 0.86) at baseline, 0.98 (R(2)  = 0.96) at 1 week, and 0.98 (R(2)  = 0.96) at 3 months. The correlations between change from baseline in the abbreviated scale and the parent scale were 0.95 (R(2)  = 0.90) and 0.96 (R(2)  = 0.92) at 7 days and 3 months, respectively. A one-point change in the RM5 has a sensitivity of 96% (95% CI = 93% to 98%) and a specificity of 92% (95% CI = 89% to 94%) for the minimum clinically significant change on the RMDQ. CONCLUSIONS: An abbreviated five-item version of the RMDQ was developed. Pending independent validation, this shortened instrument should streamline ED-based low back pain research.

The JAK2/STAT3 signaling pathway is required for growth of CD44⁺CD24⁻ stem cell-like breast cancer cells in human tumors.

Intratumor heterogeneity is a major clinical problem because tumor cell subtypes display variable sensitivity to therapeutics and may play different roles in progression. We previously characterized 2 cell populations in human breast tumors with distinct properties: CD44+CD24- cells that have stem cell-like characteristics, and CD44-CD24+ cells that resemble more differentiated breast cancer cells. Here we identified 15 genes required for cell growth or proliferation in CD44+CD24- human breast cancer cells in a large-scale loss-of-function screen and found that inhibition of several of these (IL6, PTGIS, HAS1, CXCL3, and PFKFB3) reduced Stat3 activation. We found that the IL-6/JAK2/Stat3 pathway was preferentially active in CD44+CD24- breast cancer cells compared with other tumor cell types, and inhibition of JAK2 decreased their number and blocked growth of xenografts. Our results highlight the differences between distinct breast cancer cell types and identify targets such as JAK2 and Stat3 that may lead to more specific and effective breast cancer therapies.

Genome-wide functional synergy between amplified and mutated genes in human breast cancer.

A single cancer cell contains large numbers of genetic alterations that in combination create the malignant phenotype. However, whether amplified and mutated genes form functional and physical interaction networks that could explain the selection for cells with combined alterations is unknown. To investigate this issue, we characterized copy number alterations in 191 breast tumors using dense single nucleotide polymorphism arrays and identified 1,747 genes with copy number gain organized into 30 amplicons. Amplicons were distributed unequally throughout the genome. Each amplicon had distinct enrichment pattern in pathways, networks, and molecular functions, but genes within individual amplicons did not form coherent functional units. Genes in amplicons included all major tumorigenic pathways and were highly enriched in breast cancer-causative genes. In contrast, 1,188 genes with somatic mutations in breast cancer were distributed randomly over the genome, did not represent a functionally cohesive gene set, and were relatively less enriched in breast cancer marker genes. Mutated and gained genes did not show statistically significant overlap but were highly synergistic in populating key tumorigenic pathways including transforming growth factor beta, WNT, fibroblast growth factor, and PIP3 signaling. In general, mutated genes were more frequently upstream of gained genes in transcription regulation signaling than vice versa, suggesting that mutated genes are mainly regulators, whereas gained genes are mostly regulated. ESR1 was the major transcription factor regulating amplified but not mutated genes. Our results support the hypothesis that multiple genetic events, including copy number gains and somatic mutations, are necessary for establishing the malignant cell phenotype.

Interplay of genes regulated by estrogen and diindolylmethane in breast cancer cell lines.

Diindolylmethane (DIM), a biologically active congener of indole-3-carbinol (I3C) derived from cruciferous vegetables, is a promising agent for the prevention of estrogen-sensitive cancers. Both DIM and estrogen affect transcription of genes by binding receptors, such as aryl hydrocarbon receptor (AhR) or estrogen receptors (ER). Gene regulation by DIM and estradiol (E2) can be very complex. While DIM typically binds the AhR, this complex can directly associate with the ER, recruit co-activators that bind to estrogen-responsive promoters, and activate transcription. Alternately, DIM can bind the ER directly. In this study, we have analyzed gene expression using microarray profiling and quantitative real time-polymerase chain reaction in MCF7 breast cancer cells treated with E2 (1 nM) or DIM (25 microM) alone or in combination for 16 h. The interplay of E2 and DIM was reflected in the expression of a subset of genes (<90) in which the combination of E2 and DIM acted either additively or antagonistically to alter gene expression.

Integrative genomic approaches identify IKBKE as a breast cancer oncogene.

The karyotypic chaos exhibited by human epithelial cancers complicates efforts to identify mutations critical for malignant transformation. Here we integrate complementary genomic approaches to identify human oncogenes. We show that activation of the ERK and phosphatidylinositol 3-kinase (PI3K) signaling pathways cooperate to transform human cells. Using a library of activated kinases, we identify several kinases that replace PI3K signaling and render cells tumorigenic. Whole genome structural analyses reveal that one of these kinases, IKBKE (IKKepsilon), is amplified and overexpressed in breast cancer cell lines and patient-derived tumors. Suppression of IKKepsilon expression in breast cancer cell lines that harbor IKBKE amplifications induces cell death. IKKepsilon activates the nuclear factor-kappaB (NF-kappaB) pathway in both cell lines and breast cancers. These observations suggest a mechanism for NF-kappaB activation in breast cancer, implicate the NF-kappaB pathway as a downstream mediator of PI3K, and provide a framework for integrated genomic approaches in oncogene discovery.