83 research outputs found
Prospective Evaluation of the Prognostic Implications of Improved Assay Performance With a Sensitive Assay for Cardiac Troponin I
ObjectivesThe purpose of this study was to investigate the prognostic implications of low-level increases in cardiac troponin I (cTnI) using a current-generation sensitive assay in patients with suspected acute coronary syndrome (ACS).BackgroundRecent enhancements in troponin assays have enabled resolution of the 99th percentile reference limit at progressively lower concentrations. However, the clinical significance of low-level increases with sensitive assays is still debated.MethodsWe measured cTnI using a sensitive assay (TnI-Ultra, Siemens Healthcare Diagnostics, Deerfield, Illinois) at baseline in 4,513 patients with non–ST-segment elevation ACS randomly assigned to ranolazine or placebo. We applied decision limits at the 99th percentile reference limit (0.04 μg/l), the cut point of the predecessor assay (0.1 μg/l), and 1 equivalent to elevation of creatine kinase–myocardial band (1.5 ng/ml).ResultsPatients with baseline cTnI ≥0.04 μg/l (n = 2,924) were at higher risk of death/myocardial infarction (MI) at 30 days than were patients with a negative cTnI (6.1% vs. 2.0%, p < 0.001). After adjusting for the TIMI (Thrombolysis In Myocardial Infarction) risk score, cTnI ≥0.04 μg/l was associated with a 3-fold (95% confidence interval: 2.0 to 4.4, p < 0.001) higher risk of death/MI at 30 days. Moreover, patients with low-level increases (0.04 μg/l to <0.1 μg/l), were at significantly higher risk of death/MI at 30 days (5.0% vs. 2.0%, p = 0.001) and death at 12 months (6.4% vs. 2.4%, p = 0.005) than were patients with cTnI <0.04 μg/l.ConclusionsLow-level increases in cTnI using a sensitive assay identify patients at higher risk of death or MI. These findings support current American College of Cardiology/American Heart Association recommendations defining MI, and the incremental value of newer, more sensitive assays in identifying high-risk patients with ACS
A new dominant peroxiredoxin allele identified by whole-genome re-sequencing of random mutagenized yeast causes oxidant-resistance and premature aging
The
combination of functional genomics with next generation sequencing
facilitates new experimental strategies for addressing complex biological
phenomena. Here, we report the identification of a gain-of-function allele
of peroxiredoxin (thioredoxin peroxidase, Tsa1p) via whole-genome
re-sequencing of a dominantSaccharomyces cerevisiae mutant obtained
by chemical mutagenesis. Yeast strain K6001, a screening system for
lifespan phenotypes, was treated with ethyl methanesulfonate (EMS). We
isolated an oxidative stress-resistant mutant (B7) which transmitted this
phenotype in a background-independent, monogenic and dominant way. By
massive parallel pyrosequencing, we generated an 38.8 fold whole-genome
coverage of the strains, which differed in 12,482 positions from the
reference (S288c) genome. Via a subtraction strategy, we could narrow this
number to 13 total and 4 missense nucleotide variations that were specific for
the mutant. Via expression in wild type backgrounds, we show that one of
these mutations, exchanging a residue in the peroxiredoxin Tsa1p, was
responsible for the mutant phenotype causing background-independent
dominant oxidative stress-resistance. These effects were not provoked by
altered Tsa1p levels, nor could they be simulated by deletion,
haploinsufficiency or over-expression of the wild-type allele. Furthermore,
via both a mother-enrichment technique and a micromanipulation assay, we
found a robust premature aging phenotype of this oxidant-resistant strain.
Thus, TSA1-B7 encodes for a novel dominant form of peroxiredoxin,
and establishes a new connection between oxidative stress and aging. In
addition, this study shows that the re-sequencing of entire genomes is
becoming a promising alternative for the identification of functional
alleles in approaches of classic molecular genetics
Comparative oncology: The paradigmatic example of canine and human mast cell neoplasms
In humans, advanced mast cell (MC) neoplasms are rare malignancies with a poor prognosis. Only a few preclinical models are available, and current treatment options are limited. In dogs, MC neoplasms are the most frequent malignant skin tumours. Unlike low-grade MC neoplasms, high-grade MC disorders usually have a poor prognosis with short survival. In both species, neoplastic MCs display activating KIT mutations, which are considered to contribute to disease evolution. Therefore, tyrosine kinase inhibitors against KIT have been developed. Unfortunately, clinical responses are unpredictable and often transient, which remains a clinical challenge in both species. Therefore, current efforts focus on the development of new improved treatment strategies. The field of comparative oncology may assist in these efforts and accelerate human and canine research regarding diagnosis, prognostication, and novel therapies. In this article, we review the current status of comparative oncology approaches and perspectives in the field of MC neoplasms
AID/APOBEC-network reconstruction identifies pathways associated with survival in ovarian cancer
Background Building up of pathway-/disease-relevant signatures provides a
persuasive tool for understanding the functional relevance of gene alterations
and gene network associations in multifactorial human diseases. Ovarian cancer
is a highly complex heterogeneous malignancy in respect of tumor anatomy,
tumor microenvironment including pro-/antitumor immunity and inflammation;
still, it is generally treated as single disease. Thus, further approaches to
investigate novel aspects of ovarian cancer pathogenesis aiming to provide a
personalized strategy to clinical decision making are of high priority. Herein
we assessed the contribution of the AID/APOBEC family and their associated
genes given the remarkable ability of AID and APOBECs to edit DNA/RNA, and as
such, providing tools for genetic and epigenetic alterations potentially
leading to reprogramming of tumor cells, stroma and immune cells. Results We
structured the study by three consecutive analytical modules, which include
the multigene-based expression profiling in a cohort of patients with primary
serous ovarian cancer using a self-created AID/APOBEC-associated gene
signature, building up of multivariable survival models with high predictive
accuracy and nomination of top-ranked candidate/target genes according to
their prognostic impact, and systems biology-based reconstruction of the AID
/APOBEC-driven disease-relevant mechanisms using transcriptomics data from
ovarian cancer samples. We demonstrated that inclusion of the AID/APOBEC
signature-based variables significantly improves the clinicopathological
variables-based survival prognostication allowing significant patient
stratification. Furthermore, several of the profiling-derived variables such
as ID3, PTPRC/CD45, AID, APOBEC3G, and ID2 exceed the prognostic impact of
some clinicopathological variables. We next extended the signature-/modeling-
based knowledge by extracting top genes co-regulated with target molecules in
ovarian cancer tissues and dissected potential networks/pathways/regulators
contributing to pathomechanisms. We thereby revealed that the AID/APOBEC-
related network in ovarian cancer is particularly associated with
remodeling/fibrotic pathways, altered immune response, and autoimmune
disorders with inflammatory background. Conclusions The herein study is, to
our knowledge, the first one linking expression of entire AID/APOBECs and
interacting genes with clinical outcome with respect to survival of cancer
patients. Overall, data propose a novel AID/APOBEC-derived survival model for
patient risk assessment and reconstitute mapping to molecular pathways. The
established study algorithm can be applied further for any biologically
relevant signature and any type of diseased tissue
B-Type Natriuretic Peptide and Cardiac Troponin I Are Associated With Adverse Outcomes in Stable Kidney Transplant Recipients
Approximately 200,000 kidney transplant recipients are living in the US; they are at increased risk for cardiovascular and other adverse outcomes. Biomarkers predicting these outcomes are needed. Using specimens collected during the FAVORIT (Folic Acid for Vascular Outcome Reduction In Transplantation) trial, we determined whether plasma levels of B-type natriuretic peptide (BNP) and cardiac troponin I are associated with adverse outcomes in stable kidney transplant recipients
Proposed Diagnostic Criteria and Classification of Canine Mast Cell Neoplasms: A Consensus Proposal
Mast cell neoplasms are one of the most frequently diagnosed malignancies in dogs. The clinical picture, course, and prognosis vary substantially among patients, depending on the anatomic site, grade and stage of the disease. The most frequently involved organ is the skin, followed by hematopoietic organs (lymph nodes, spleen, liver, and bone marrow) and mucosal sites of the oral cavity and the gastrointestinal tract. In cutaneous mast cell tumors, several grading and staging systems have been introduced. However, no comprehensive classification and no widely accepted diagnostic criteria have been proposed to date. To address these open issues and points we organized a Working Conference on canine mast cell neoplasms in Vienna in 2019. The outcomes of this meeting are summarized in this article. The proposed classification includes cutaneous mast cell tumors and their sub-variants defined by grading- and staging results, mucosal mast cell tumors, extracutaneous/extramucosal mast cell tumors without skin involvement, and mast cell leukemia (MCL). For each of these entities, diagnostic criteria are proposed. Moreover, we have refined grading and staging criteria for mast cell neoplasms in dogs based on consensus discussion. The criteria and classification proposed in this article should greatly facilitate diagnostic evaluation and prognostication in dogs with mast cell neoplasms and should thereby support management of these patients in daily practice and the conduct of clinical trials
Antibody-targeting of ultra-small nanoparticles enhances imaging sensitivity and enables longitudinal tracking of multiple myeloma
Monitoring malignant progression and disease recurrence post-therapy are central challenges to improving the outcomes of patients with multiple myeloma (MM). Whereas current detection methods that rely upon bone marrow examination allow for precise monitoring of minimal residual disease and can help to elucidate clonal evolution, they do not take into account the spatial heterogeneity of the tumor microenvironment. As such, they are uninformative as to the localization of malignant plasma cells and may lead to false negative results. With respect to the latter challenge, clinically-available imaging agents are neither sufficiently sensitive nor specific enough to detect minute plasma cell populations. Here, we sought to explore methods by which to improve detection of MM cells within their natural bone marrow environment, using whole-animal magnetic resonance imaging to longitudinally monitor early-stage disease as well as to enhance tumor detection after systemic therapy. We conducted a proof-of-concept study to demonstrate that ultra-small
Endothelin-1, outcomes in patients with heart failure and reduced ejection fraction, and effects of dapagliflozin: Findings from DAPA-HF
BACKGROUND:
ET-1 (endothelin-1) is implicated in the pathophysiology of heart failure and renal disease. Its prognostic importance and relationship with kidney function in patients with heart failure with reduced ejection fraction receiving contemporary treatment are uncertain. We investigated these and the efficacy of dapagliflozin according to ET-1 level in the DAPA-HF trial (Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure).
METHODS:
We investigated the incidence of the primary outcome (cardiovascular death or worsening heart failure), change in kidney function, and the effect of dapagliflozin according to baseline ET-1 concentration, adjusting in Cox models for other recognized prognostic variables in heart failure including NT-proBNP (N-terminal pro-B-type natriuretic peptide). We also examined the effect of dapagliflozin on ET-1 level.
RESULTS:
Overall, 3048 participants had baseline ET-1 measurements of: tertile 1 (T1; ≤3.28 pg/mL; n=1016); T2 (>3.28–4.41 pg/mL; n=1022); and T3 (>4.41 pg/mL; n=1010). Patients with higher ET-1 were more likely male, more likely obese, and had lower left ventricular ejection fraction, lower estimated glomerular filtration rate, worse functional status, and higher NT-proBNP and hs-TnT (high-sensitivity troponin-T).
In the adjusted Cox models, higher baseline ET-1 was independently associated with worse outcomes and steeper decline in kidney function (adjusted hazard ratio for primary outcome of 1.95 [95% CI, 1.53–2.50] for T3 and 1.36 [95% CI, 1.06–1.75] for T2; both versus T1; estimated glomerular filtration rate slope: T3, –3.19 [95% CI, –3.66 to –2.72] mL/min/1.73 m2/y, T2, –2.08 [95% CI, –2.52 to –1.63] and T1 –2.35 [95% CI, –2.79 to –1.91]; P=0.002).
The benefit of dapagliflozin was consistent regardless of baseline ET-1, and the placebo-corrected decrease in ET-1 with dapagliflozin was 0.13 pg/mL (95% CI, 0.25–0.01; P=0.029).
CONCLUSIONS:
Higher baseline ET-1 concentration was independently associated with worse clinical outcomes and more rapid decline in kidney function. The benefit of dapagliflozin was consistent across the range of ET-1 concentrations measured, and treatment with dapagliflozin led to a small decrease in serum ET-1 concentration.
REGISTRATION:
URL: https://www.clinicaltrials.gov; Unique identifier: NCT03036124
Recommended from our members
Interleukin 18 function in atherosclerosis is mediated by the interleukin 18 receptor and the Na-Cl co-transporter
Interleukin-18 (IL18) participates in atherogenesis through several putative mechanisms1, 2. Interruption of IL18 action reduces atherosclerosis in mice3, 4. Here, we show that absence of the IL18 receptor (IL18r) does not affect atherosclerosis in apolipoprotein E–deficient (Apoe−/−) mice, nor does it affect IL18 cell surface binding to or signaling in endothelial cells. As identified initially by co-immunoprecipitation with IL18, we found that IL18 interacts with the Na-Cl co-transporter (NCC; also known as SLC12A3), a 12-transmembrane-domain ion transporter protein preferentially expressed in the kidney5. NCC is expressed in atherosclerotic lesions, where it colocalizes with IL18r. In Apoe−/− mice, combined deficiency of IL18r and NCC, but not single deficiency of either protein, protects mice from atherosclerosis. Peritoneal macrophages from Apoe−/− mice or from Apoe−/− mice lacking IL18r or NCC show IL18 binding and induction of cell signaling and cytokine and chemokine expression, but macrophages from Apoe−/− mice with combined deficiency of IL18r and NCC have a blunted response. An interaction between NCC and IL18r on macrophages was detected by co-immunoprecipitation. IL18 binds to the cell surface of NCC-transfected COS-7 cells, which do not express IL18r, and induces cell signaling and cytokine expression. This study identifies NCC as an IL18-binding protein that collaborates with IL18r in cell signaling, inflammatory molecule expression, and experimental atherogenesis
- …