Most discriminative stimuli for functional cell type clustering.

Identifying cell types and understanding their functional properties is crucial for unraveling the mechanisms underlying perception and cognition. In the retina, functional types can be identified by carefully selected stimuli, but this requires expert domain knowledge and biases the procedure towards previously known cell types. In the visual cortex, it is still unknown what functional types exist and how to identify them. Thus, for unbiased identification of the functional cell types in retina and visual cortex, new approaches are needed. Here we propose an optimization-based clustering approach using deep predictive models to obtain functional clusters of neurons using Most Discriminative Stimuli (MDS). Our approach alternates between stimulus optimization with cluster reassignment akin to an expectation-maximization algorithm. The algorithm recovers functional clusters in mouse retina, marmoset retina and macaque visual area V4. This demonstrates that our approach can successfully find discriminative stimuli across species, stages of the visual system and recording techniques. The resulting most discriminative stimuli can be used to assign functional cell types fast and on the fly, without the need to train complex predictive models or show a large natural scene dataset, paving the way for experiments that were previously limited by experimental time. Crucially, MDS are interpretable: they visualize the distinctive stimulus patterns that most unambiguously identify a specific type of neuron.

Molecular heterogeneity in histomorphologic subtypes of lung adeno carcinoma represents a challenge for treatment decision.

Lung cancer is the leading cause in cancer related death, with non-small cell lung cancer (NSCLC) being the most frequent subtype. The importance of NSCLC is reflected by the various targeted therapy options especially for NSCLC adenocarcinomas (lung adeno carcinoma (LUAD)) as well as a set of options for immune therapies. However, despite these therapy advances, the majority of patients do not show a long-term response to either targeted therapy or immune checkpoint inhibition. One reason for treatment failure appears to be the NSCLC tumor heterogeneity. NSCLC heterogeneity might lead to an insufficient molecular characterization of a given sample due to the limited tumor material used for pathological assessment as the majority of analyses is performed on small biopsies. To get a more detailed insight into the tumor heterogeneity of NSCLC LUAD, especially in the light of its different histomorphological growth patterns, we analysed isolated NSCLC growth pattern areas and the corresponding entire tumor samples of a cohort of 31 NSLCS LUAD patients and compared their mutational landscape and their expression profiles. While significant differences of complex biomarkers, like tumor mutational burden (TMB) or microsatellite instability (MSI), were not detected between the five growth patterns -lepidic, papillary, micropapillary, acinar, and solid- we observed various subclonal mutations and copy number variants. Moreover, RNASeq analysis revealed growth pattern specific expression profiles affecting cellular processes like apoptosis, metastasis and proliferation. Taken together, our data provide novel insights into the tumor heterogeneity of LUAD required to overcome tumor heterogeneity related therapy resistance.

Droplet Motion Driven by Liquid Dielectrophoresis in the Low-Frequency Range.

Electrohydrodynamic wetting manipulation plays a major role in modern microfluidic technologies such as lab-on-a-chip applications and digital microfluidics. Liquid dielectrophoresis (LDEP) is a common driving mechanism, which induces hydrodynamic motion in liquids by the application of nonhomogeneous electrical fields. Among strategies to analyze droplet movement, systematic research on the influence of different frequencies under AC voltage is missing. In this paper, we therefore present a first study covering the motion characteristics of LDEP-driven droplets of the dielectric liquids ethylene glycol and glycerol carbonate in the driving voltage frequency range from 50 Hz to 1600 Hz. A correlation between the switching speed of LDEP-actuated droplets in a planar electrode configuration and the frequency of the applied voltage is shown. Hereby, motion times of different-sized droplets could be reduced by up to a factor of 5.3. A possible excitation of the droplets within their range of eigenfrequencies is investigated using numerical calculations. The featured fluidic device is designed using larger-sized electrodes rather than typical finger or strip electrodes, which are commonly employed in LDEP devices. The influence of the electrode shape is considered simulatively by studying the electric field gradients.

[Asymptomatic SARS-CoV-2 Infection and "in situ split" Liver Resection with Fatal Outcome - A Case Report]. / SARS-CoV-2-Infektion und "In-situ-Split"-Leberresektion mit tödlichem Verlauf.

We report the perioperative course of a 47-year-old patient who underwent a two-stage liver resection for bilobar metastatic colorectal carcinoma. The respiratory asymptomatic patient was tested positive for SARS-CoV-2 by PCR detection one day before the second surgical procedure. Postoperatively, the patient suffered cardiovascular arrest on postoperative day 8 and died despite immediately initiated resuscitative measures. With an initial clinical suspicion of vascular liver failure, postmortem pathologic examination revealed the underlying cause of death to be COVID-19-related myocarditis with acute right heart failure. Individual multidisciplinary risk assessment should be considered very critically when deviating from the "7-week rule" because the benefit is difficult to objectify, even in oncologic patients.

Evaluation of a preservative-free, cross-linked sodium hyaluronate-based solution, Lacri +®, in dogs with dry eye: a pilot trial.

BACKGROUND: The purpose of this pilot trial was to evaluate the efficacy and benefits of a preservative-free cross-linked sodium hyaluronate solution (Lacri +®, MP Labo, France) in 19 privately-owned dogs with dry eye. The animals were administered 2 drops of the tested product in each affected eye, twice a day (BID) for 30 days. Improvement in the global ocular clinical score (sum of the individual scores for conjunctivitis, ocular discharge, eye irritation, and corneal opacity/pigmentation/vascularization, each rated from 0 to 3) was defined as the primary outcome. Besides an improvement in each individual ocular score, tear film quality (Tear Break Up Time, TBUT), dogs' and owners' quality of life (QoL), as well as an increase in tear production (Schirmer Tear Test-1, STT1), were considered secondary outcomes. These criteria were assessed on D0, D0 + 15 days, and D0 + 30 days. Finally, a qualitative evaluation of clinical improvement was requested from the owners on D0 + 2, + 15 & + 30 days and from the investigators during the follow-up. RESULTS: The global clinical ocular score as well as the individual conjunctival and irritation scores improved significantly (p < 0.0001) during the pilot trial. The average reduction of the global score reached 30% on D0 + 15 days and 55% on D0 + 30 days compared to D0. Ocular discharge was significantly lower (p = 0.0002) on D0 + 30 days compared to baseline; however corneal opacity did not show any significant changes from D0 to the end of the follow-up period. The quantitative tear production was increased at D + 30 (p < 0.0001), with a significant improvement as soon as 2 weeks in, with around 30% and 60% of dogs presenting an STT1 value above 10 on D0 + 15 days and on D0 + 30 days, respectively. The QoL score was significantly improved compared to D0 at all time points (p < 0.0001). After 2 days of treatment, 39% of the owners rated the efficacy as "good". The efficacy of the tested product was considered "Good" or "Very Good" by the investigators in 78% and 93% of the cases, on D0 + 15 days and D0 + 30 days, respectively. The tolerance of this preservative-free formulation was good, with only rare and transient minor local reactions, realated to administration rather than the product itself.

Association between Intraoperative Blood Transfusion, Regional Anesthesia and Outcome after Pediatric Tumor Surgery for Nephroblastoma.

BACKGROUND: Recent data suggest that anesthesiologic interventions-e.g., the choice of the anesthetic regimen or the administration of blood products-might play a major role in determining outcome after tumor surgery. In contrast to adult patients, only limited data are available regarding the potential association of anesthesia and outcome in pediatric cancer patients. METHODS: A retrospective multicenter study assessing data from pediatric patients (0-18 years of age) undergoing surgery for nephroblastoma between 2004 and 2018 was conducted at three academic centers in Europe. Overall and recurrence-free survival were the primary outcomes of the study and were evaluated for a potential impact of intraoperative administration of erythrocyte concentrates, the use of regional anesthesia and the choice of the anesthetic regimen. The length of stay on the intensive care unit, the time to hospital discharge after surgery and blood neutrophil-to-lymphocyte ratio were defined as secondary outcomes. RESULTS: In total, data from 65 patients were analyzed. Intraoperative administration of erythrocyte concentrates was associated with a reduction in recurrence-free survival (hazard ratio (HR) 7.59, 95% confidence interval (CI) 1.36-42.2, p = 0.004), whereas overall survival (HR 5.37, 95% CI 0.42-68.4, p = 0.124) was not affected. The use of regional anesthesia and the choice of anesthetic used for maintenance of anesthesia did not demonstrate an effect on the primary outcomes. It was, however, associated with fewer ICU transfers, a shortened time to discharge and a decreased postoperative neutrophil-to-lymphocyte ratio. CONCLUSIONS: The current study provides the first evidence for a possible association between blood transfusion as well as anesthesiologic interventions and outcome after pediatric cancer surgery.

Active reconfiguration of cytoplasmic lipid droplets governs migration of nutrient-limited phytoplankton.

Nutrient availability, along with light and temperature, drives marine primary production. The ability to migrate vertically, a critical trait of motile phytoplankton, allows species to optimize nutrient uptake, storage, and growth. However, this traditional view discounts the possibility that migration in nutrient-limited waters may be actively modulated by the emergence of energy-storing organelles. Here, we report that bloom-forming raphidophytes harness energy-storing cytoplasmic lipid droplets (LDs) to biomechanically regulate vertical migration in nutrient-limited settings. LDs grow and translocate directionally within the cytoplasm, steering strain-specific shifts in the speed, trajectory, and stability of swimming cells. Nutrient reincorporation restores their swimming traits, mediated by an active reconfiguration of LD size and coordinates. A mathematical model of cell mechanics establishes the mechanistic coupling between intracellular changes and emergent migratory behavior. Amenable to the associated photophysiology, LD-governed behavioral shift highlights an exquisite microbial strategy toward niche expansion and resource optimization in nutrient-limited oceans.

Body height among adult male and female Swiss Health Survey participants in 2017: Trends by birth years and associations with self-reported health status and life satisfaction.

The increase in adult height for 150 years is linked to overall improvements in nutrition, hygiene, and living standards. Height is positively associated with general health and success on various levels (e.g. quality of life, earnings or happiness). The aim of this study was to investigate whether different subgroups show different trends across birth cohorts. We wanted to know whether taller individuals considered themselves as healthier and their quality of life as better than shorter individuals. We included 19,435 participants from the Swiss population-based Health Survey 2017. GAM were used to assess nonlinear associations between height and birth year. Multinomial logistic regression was used to predict probabilities of self-rated health in relation to height. The increase in average height slows down from the 1970s birth cohorts. Participants with parents from Central/Northern/Western Europe (men 177.9 cm, women: 165.1 cm) or Eastern Europe (men 178.7 cm, women: 165.7 cm) were taller than participants with parents from South America (men 174.3 cm, women: 161. cm) and Asia (men 173.2 cm, women: 160.1 cm). Participants with tertiary education were taller than participants from education levels (mean difference men: 4.5 cm, women: 5.0 cm). Height was positively associated with self-declared aspects of health and life satisfaction. These results support the conclusion that body height as a co-factor of health aspects should be considered in public health research. Although adult body height can no longer be influenced, nutritional status and thus also healthy growth can be influenced in childhood by public health programs, by eliminating social inequalities, and by strengthen healthy living conditions.

Small-molecule activation of OGG1 increases oxidative DNA damage repair by gaining a new function.

Oxidative DNA damage is recognized by 8-oxoguanine (8-oxoG) DNA glycosylase 1 (OGG1), which excises 8-oxoG, leaving a substrate for apurinic endonuclease 1 (APE1) and initiating repair. Here, we describe a small molecule (TH10785) that interacts with the phenylalanine-319 and glycine-42 amino acids of OGG1, increases the enzyme activity 10-fold, and generates a previously undescribed ß,δ-lyase enzymatic function. TH10785 controls the catalytic activity mediated by a nitrogen base within its molecular structure. In cells, TH10785 increases OGG1 recruitment to and repair of oxidative DNA damage. This alters the repair process, which no longer requires APE1 but instead is dependent on polynucleotide kinase phosphatase (PNKP1) activity. The increased repair of oxidative DNA lesions with a small molecule may have therapeutic applications in various diseases and aging.

Two Facets of Emotion Dysregulation Are Core Symptomatic Domains in Adult ADHD: Results from the SR-WRAADDS, a Broad Symptom Self-Report Questionnaire.

OBJECTIVES: Emotional dysregulation (ED) in adult ADHD is frequent but definition and tools for its evaluation are not consensual. Our aim was to determine the core ADHD symptomatic domains via the Self-Reported Wender-Reimherr Adult Attention Deficit Disorder Scale (SR-WRAADDS) following its validation in a large clinical sample of adults with ADHD and controls. METHOD: Three hundred sixty-nine adult patients with ADHD and 251 healthy participants completed the SR-WRAADDS and questionnaires about ADHD, depression, and ED. We analyzed the psychometric properties of the SR-WRAADDS and a factor analysis yielded symptomatic domains. RESULTS: The SR-WRAADDS has good reliability. The 30 symptoms were best organized in a four-factor solution: attention/disorganization, hyperactivity/restlessness, impulsivity/emotional outbursts, and emotional lability. CONCLUSIONS: The symptomatic structure of the SR-WRAADDS includes two distinct dimensions related to ED: "impulsivity/emotional outbursts" and "emotional lability." The SR-WRAADDS is a reliable and clinically useful tool that assesses all ADHD symptom domains, including facets of ED.

Evolution of Blood-Brain Barrier Permeability in Subacute Ischemic Stroke and Associations With Serum Biomarkers and Functional Outcome.

Background and Purpose: In the setting of acute ischemic stroke, increased blood-brain barrier permeability (BBBP) as a sign of injury is believed to be associated with increased risk of poor outcome. Pre-clinical studies show that selected serum biomarkers including C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNFα), matrix metallopeptidases (MMP), and vascular endothelial growth factors (VEGFs) may play a role in BBBP post-stroke. In the subacute phase of stroke, increased BBBP may also be caused by regenerative mechanisms such as vascular remodeling and therefore may improve functional recovery. Our aim was to investigate the evolution of BBBP in ischemic stroke using contrast-enhanced (CE) magnetic resonance imaging (MRI) and to analyze potential associations with blood-derived biomarkers as well as functional recovery in subacute ischemic stroke patients. Methods: This is an exploratory analysis of subacute ischemic stroke patients enrolled in the BAPTISe study nested within the randomized controlled PHYS-STROKE trial (interventions: 4 weeks of aerobic fitness training vs. relaxation). Patients with at least one CE-MRI before (v1) or after (v2) the intervention were eligible for this analysis. The prevalence of increased BBBP was visually assessed on T1-weighted MR-images based on extent of contrast-agent enhancement within the ischemic lesion. The intensity of increased BBBP was assessed semi-quantitatively by normalizing the mean voxel intensity within the region of interest (ROI) to the contralateral hemisphere ("normalized CE-ROI"). Selected serum biomarkers (high-sensitive CRP, IL-6, TNF-α, MMP-9, and VEGF) at v1 (before intervention) were analyzed as continuous and dichotomized variables defined by laboratory cut-off levels. Functional outcome was assessed at 6 months after stroke using the modified Rankin Scale (mRS). Results: Ninety-three patients with a median baseline NIHSS of 9 [IQR 6-12] were included into the analysis. The median time to v1 MRI was 30 days [IQR 18-37], and the median lesion volume on v1 MRI was 4 ml [IQR 1.2-23.4]. Seventy patients (80%) had increased BBBP visible on v1 MRI. After the trial intervention, increased BBBP was still detectable in 52 patients (74%) on v2 MRI. The median time to v2 MRI was 56 days [IQR 46-67]. The presence of increased BBBP on v1 MRI was associated with larger lesion volumes and more severe strokes. Aerobic fitness training did not influence the increase of BBBP evaluated at v2. In linear mixed models, the time from stroke onset to MRI was inversely associated with normalized CE-ROI (coefficient -0.002, Standard Error 0.007, p < 0.01). Selected serum biomarkers were not associated with the presence or evolution of increased BBBP. Multivariable regression analysis did not identify the occurrence or evolution of increased BBBP as an independent predictor of favorable functional outcome post-stroke. Conclusion: In patients with moderate-to-severe subacute stroke, three out of four patients demonstrated increased BBB permeability, which decreased over time. The presence of increased BBBP was associated with larger lesion volumes and more severe strokes. We could not detect an association between selected serum biomarkers of inflammation and an increased BBBP in this cohort. No clear association with favorable functional outcome was observed. Trial registration: NCT01954797.

Spatial distribution of immune checkpoint proteins in histological subtypes of lung adenocarcinoma.

The most prevalent histological type of non-small cell lung cancer (NSCLC) is adenocarcinoma. The WHO classifies this tumor into subtypes according to the predominant growth pattern such as lepidic, acinar, papillary, solid or micropapillary, each harboring specific molecular features. NSCLC adenocarcinoma heterogeneity is discussed to be a reason for therapy failure using targeted therapy or immune checkpoint inhibitors. For successful therapy of immune checkpoint inhibitors the expression and distribution of the involved immune checkpoint proteins is essential. Therefore, we aimed to investigate the distribution of five prominent immune checkpoint proteins in regard of the histological growth patterns of lung adenocarcinoma. We performed immunohistochemical staining of 84 tumor segments from 22 resected tumor samples to evaluate the expression of PD-L1, PD-1, Nectin-2, PVR, and TIGIT in distinct growth patterns of lung adenocarcinoma. We determined a distinct heterogeneity between and within different tumor segments regarding morphological growth patterns. Furthermore, expression of immune checkpoint proteins varied between different growth pattern areas as well as within one distinct growth pattern. Expression of PVR was significantly higher in solid compared to acinar growth pattern (p= 0.00736). Of note, we detected TIGIT not only on tumor infiltrating lymphocytes but also on tumor cells, whereas non-neoplastic lung tissue was consistently TIGIT-negative. The immune checkpoint protein distribution in histologic subtypes of pulmonary adenocarcinoma displays an considerable intra- and intertumoral heterogeneity implying the requirement of either a multiregion or an adjusted analysis when determining the expression status of PD-1:PD-L1 and the TIGIT:PVR/Nectin-2 checkpoint proteins as predictive markers.

Local Anesthetics and Recurrence after Cancer Surgery-What's New? A Narrative Review.

The perioperative use of regional anesthesia and local anesthetics is part of almost every anesthesiologist's daily clinical practice. Retrospective analyses and results from experimental studies pointed towards a potential beneficial effect of the local anesthetics regarding outcome-i.e., overall and/or recurrence-free survival-in patients undergoing cancer surgery. The perioperative period, where the anesthesiologist is responsible for the patients, might be crucial for the further course of the disease, as circulating tumor cells (shed from the primary tumor into the patient's bloodstream) might form new micro-metastases independent of complete tumor removal. Due to their strong anti-inflammatory properties, local anesthetics might have a certain impact on these circulating tumor cells, either via direct or indirect measures, for example via blunting the inflammatory stress response as induced by the surgical stimulus. This narrative review highlights the foundation of these principles, features recent experimental and clinical data and provides an outlook regarding current and potential future research activities.

Small molecule inhibitor of OGG1 blocks oxidative DNA damage repair at telomeres and potentiates methotrexate anticancer effects.

The most common oxidative DNA lesion is 8-oxoguanine which is mainly recognized and excised by the 8-oxoG DNA glycosylase 1 (OGG1), initiating the base excision repair (BER) pathway. Telomeres are particularly sensitive to oxidative stress (OS) which disrupts telomere homeostasis triggering genome instability. In the present study, we have investigated the effects of inactivating BER in OS conditions, by using a specific inhibitor of OGG1 (TH5487). We have found that in OS conditions, TH5487 blocks BER initiation at telomeres causing an accumulation of oxidized bases, that is correlated with telomere losses, micronuclei formation and mild proliferation defects. Moreover, the antimetabolite methotrexate synergizes with TH5487 through induction of intracellular reactive oxygen species (ROS) formation, which potentiates TH5487-mediated telomere and genome instability. Our findings demonstrate that OGG1 is required to protect telomeres from OS and present OGG1 inhibitors as a tool to induce oxidative DNA damage at telomeres, with the potential for developing new combination therapies for cancer treatment.

Hypertension delays viral clearance and exacerbates airway hyperinflammation in patients with COVID-19.

In coronavirus disease 2019 (COVID-19), hypertension and cardiovascular diseases are major risk factors for critical disease progression. However, the underlying causes and the effects of the main anti-hypertensive therapies-angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs)-remain unclear. Combining clinical data (n = 144) and single-cell sequencing data of airway samples (n = 48) with in vitro experiments, we observed a distinct inflammatory predisposition of immune cells in patients with hypertension that correlated with critical COVID-19 progression. ACEI treatment was associated with dampened COVID-19-related hyperinflammation and with increased cell intrinsic antiviral responses, whereas ARB treatment related to enhanced epithelial-immune cell interactions. Macrophages and neutrophils of patients with hypertension, in particular under ARB treatment, exhibited higher expression of the pro-inflammatory cytokines CCL3 and CCL4 and the chemokine receptor CCR1. Although the limited size of our cohort does not allow us to establish clinical efficacy, our data suggest that the clinical benefits of ACEI treatment in patients with COVID-19 who have hypertension warrant further investigation.

Targeting OGG1 arrests cancer cell proliferation by inducing replication stress.

Altered oncogene expression in cancer cells causes loss of redox homeostasis resulting in oxidative DNA damage, e.g. 8-oxoguanine (8-oxoG), repaired by base excision repair (BER). PARP1 coordinates BER and relies on the upstream 8-oxoguanine-DNA glycosylase (OGG1) to recognise and excise 8-oxoG. Here we hypothesize that OGG1 may represent an attractive target to exploit reactive oxygen species (ROS) elevation in cancer. Although OGG1 depletion is well tolerated in non-transformed cells, we report here that OGG1 depletion obstructs A3 T-cell lymphoblastic acute leukemia growth in vitro and in vivo, validating OGG1 as a potential anti-cancer target. In line with this hypothesis, we show that OGG1 inhibitors (OGG1i) target a wide range of cancer cells, with a favourable therapeutic index compared to non-transformed cells. Mechanistically, OGG1i and shRNA depletion cause S-phase DNA damage, replication stress and proliferation arrest or cell death, representing a novel mechanistic approach to target cancer. This study adds OGG1 to the list of BER factors, e.g. PARP1, as potential targets for cancer treatment.

Datasets describing the introduction of the high-sensitive troponin in the emergency department.

Chest pain is a common clinical condition in the emergency department. A high sensitive (hs) troponin test assay may help to identify patients with acute coronary syndrome earlier compared to conventional tests but also entails the risk of a high proportion of positive test results in patients without cardiac disease. We assessed the impact of the introduction of the hs-troponin test in clinical practice in an emergency department. We compared December 1, 2009 until November 30, 2010 (standard test period) to December 1, 2010 - the date of the introduction of the hs-troponin assay - until December 31, 2011 (hs troponin test period) of patients presenting with chest pain to one of the ten largest hospitals in Switzerland. We identified electronic health records using the following ICD-10 codes: R06.4 (hyperventilation), R07.1 (chest pain when breathing), R07.2 (precordial pain), R07.3 (other chest pain), and R07.4 (chest pain not specified), I20 (angina pectoris), I21 (acute MI), I22 (recurrent MI), I23 (complications after acute MI), and I24 (other acute ischemic heart disease). Included were all medical records of adult patients (≥18 years) presenting to the ED with chest pain and with ≥1 troponin test. Excluded were records without troponin test, pregnancy, trauma patients/life-threatening conditions, malignant disease, current fracture, renal replacement therapy/severe kidney failure (creatinine clearance <30ml/min/1.73m2), patients with disability, or patients disagreeing that their data will be used for scientific purposes. Two researchers screened all records for in-/exclusion. The first presentation for chest pain to the ED and all presentations within the following three months extracted. Presentations after >3 months due to chest pain were defined as a new index visit of a second episode. The extraction form with predefined variables was pilot-tested in 20 records. Additional diagnostic tests were ECG, treadmill test, coronary angiography, MIBI scintigraphy, echocardiography, chest X-ray, computer tomography (CT) of the chest or abdomen, sonography of the abdomen or pleura, gastroscopy, and lung function tests. We compared the number of non-invasive / invasive cardiac diagnostic tests in troponin positive and negative patients and the number of diagnostic tests after the exclusion of patients with STEMI diagnosis. Non-invasive / invasive cardiac tests included treadmill test, coronary angiography, MIBI scintigraphy, and echocardiography. We calculated average monthly tests per patient and compared mean tests per patient between groups. We used a t-test to quantify the evidence for differential number of diagnostic tests per patient in each period. Between-group differences were estimated with 95% confidence intervals. All analyses were performed with the statistical software R for windows [1]. Interpretation of this data can be found in a research article titled Impact of the introduction of high-sensitive troponin assay on the evaluation of chest pain patients in the emergency department: a retrospective study [2]).

Usefulness of Serum Free Thyroxine Concentration to Predict Ventricular Arrhythmia Risk in Euthyroid Patients With Structural Heart Disease.

The aim of the present study was to determine whether free thyroxine (FT4) and calculated thyroid parameters predict the incidence of ventricular arrhythmias in euthyroid heart failure patients with implantable cardioverter-defibrillators (ICD). In this open-label prospective cohort study, 115 consecutive euthyroid patients (mean age 62.9 ± 1.3 years; 87% male; ischemic cardiomyopathy 63%) scheduled for primary prevention ICD implantation or exchange were enrolled. Serum concentrations of thyrotropin (thyroid-stimulating hormone) and FT4 were measured 1 day before device operation. Primary and secondary end points were defined as occurrence of appropriate ICD therapy (AIT) and cardiovascular death, respectively. During a mean follow-up of 1,191 ± 35 days, 24 patients (21%) experienced AIT, and cardiovascular death was observed in 10 patients (9%). Patients with AIT had higher FT4 concentrations compared with those without AIT (18.9 ± 0.48 vs 16.2 ± 0.22 pmol/L, p <0.001). FT4 was an independent predictor of AIT in an adjusted Cox regression (hazard ratio = 1.47, p <0.001). Kaplan-Meier analysis demonstrated that Jostel's thyroid-stimulating hormone index, reflecting the central component of the hypothalamus-pituitary-thyroid loop, and SPINA-GT as surrogate markers for thyroid's secretory capacity predicted AIT incidences. None of the indices predicted cardiovascular death. In conclusion, FT4 concentration predicts an increased incidence of ventricular arrhythmias in euthyroid patients receiving ICDs for primary prevention. Our data suggest that both impending primary hyperthyroidism and an increased thyroid homeostasis set point may increase the rate of AIT in this patient population.

Impact of the Introduction of High-Sensitive Troponin Assay in the Emergency Department: A Retrospective Study.

BACKGROUND: Compared with troponin T/I test, the introduction of a high-sensitive (hs) troponin test may result in a higher proportion of positive test results in patients with chest pain and over-testing in patients without acute coronary syndrome. We assessed the impact of the introduction of the hs-troponin assay on the discharge diagnoses and the number of diagnostic tests in patients presenting with chest pain in a real-life setting in an emergency department. METHODS: Retrospective chart review of patients presenting with chest pain to one of the largest hospitals in Switzerland. We compared the standard troponin period (December 2009 to November 2010) with the hs-troponin period (December 2010 to December 2011). RESULTS: Data from 1274 patients (standard 597 [46.9%], hs-troponin 677 [53.1%]) were analyzed. The proportion of patients with non-ST-segment elevation myocardial infarction increased (hs-troponin 14.9%, compared with 9.7%); the proportion in unstable angina (1.5% to 4.0%) and other cardiac illnesses (8.1% to 11.7%) decreased. Although the proportion of noncardiac chest pain illnesses (67%) remained unchanged, the proportion of positive hs-troponin was higher (6.1% vs 2.0%). The average number of additional tests/person decreased in troponin-positive patients (2.0 to 1.7 test per patient; P = .02) and troponin-negative patients (3.1 to 2.8 tests; P < .0001). CONCLUSION: Although the introduction of the hs-troponin test resulted in a higher proportion of positive hs-troponin tests in patients with noncardiac chest pain, the average number of diagnostic tests decreased in patients with chest pain presenting to an emergency department, indicating an increased confidence of clinicians in their diagnosis.