Styrene alters potassium endolymphatic concentration in a model of cultured utricle explants

Despite well-documented neurotoxic and ototoxic properties, styrene remains commonly used in industry. Its effects on the cochlea have been extensively studied in animals, and epidemiological and animal evidence indicates an impact on balance. However, its influence on the peripheral vestibular receptor has yet to be investigated. Here, we assessed the vestibulotoxicity of styrene using an in vitro model, consisting of three-dimensional cultured newborn rat utricles filled with a high‑potassium (K⁺) endolymph-like fluid, called "cysts". K⁺ entry in the cyst ("influx") and its exit ("efflux") are controlled by secretory cells and hair cells, respectively. The vestibular epithelium's functionality is thus linked to K⁺ concentration, measured using a microelectrode. Known inhibitors of K⁺ efflux and influx validated the model. Cysts were subsequently exposed to styrene (0.25; 0.5; 0.75 and 1 mM) for 2 h or 72 h. The decrease in K⁺ concentration measured after both exposure durations was dose-dependent, and significant from 0.75 mM styrene. Vacuoles were visible in the cytoplasm of epithelial cells from 0.5 mM after 2 h and from 0.25 mM after 72 h. The results presented here are the first evidence that styrene may deregulate K⁺ homeostasis in the endolymphatic space, thereby altering the functionality of the vestibular receptor.

Placental expression of leptin: fetal sex-independent relation with human placental growth

OBJECTIVES

Leptin (LEP) is a vital placental hormone that is known to affect different aspects of placental function and fetal development. The present study aimed to determine the association of placental LEP transcript abundance with maternal, placental, and newborn parameters.

SUBJECTS/METHODS

In this retrospective case-control study, placental samples (n = 105) were collected from small (SGA) and appropriate (AGA) for gestational age full-term singleton pregnancies (n = 44 SGA and n = 61 AGA). Placental transcript abundance of LEP was assessed by real-time quantitative PCR after normalization to a reference gene panel. LEP methylation was measured using a quantitative MethyLight assay in a subset of samples (n = 54).

RESULTS

Placental LEP transcript abundance was negatively and significantly associated with placental weight (β = -3.883, P = 0.015). This association continued to be significant in the SGA group (β = -10.332, P = 0.001), both in female (β = -15.423, P = 0.021) and male births (β = -10.029, P = 0.007). LEP transcript abundance was not associated with LEP methylation levels (Spearman's ρ = 0.148, P = 0.287).

CONCLUSION

We conclude that placental upregulation of LEP is an integral and fetal sex-independent component of placental growth restriction, which can be potentially targeted through maternal dietary modifications to improve fetoplacental growth.

Levels of anxiety, depression and denial in patients with myocardial infarction

In this study we investigated 1) the changes in anxiety, depression and denial from admission to discharge in patients admitted to the intensive care unit following an acute myocardial infarction and 2) the effect of smoking habits, time lapsed from the appearance of symptoms to seeking help behavior, presence of a person that motivated the patient to seek help, previous myocardial infarction (MI) and family history of MI, on these changes. The results indicated that 1) the levels of both anxiety and depression increased from admission to discharge, while denial decreased; 2) positive family history of MI was associated with lower difference of denial between admission and discharge.

Signatures of the d^{*}(2380) Hexaquark in d(γ,pn[over →])

We report a measurement of the spin polarization of the recoiling neutron in deuterium photodisintegration, utilizing a new large acceptance polarimeter within the Crystal Ball at MAMI. The measured photon energy range of 300-700 MeV provides the first measurement of recoil neutron polarization at photon energies where the quark substructure of the deuteron plays a role, thereby providing important new constraints on photodisintegration mechanisms. A very high neutron polarization in a narrow structure centered around E_{γ}∼570  MeV is observed, which is inconsistent with current theoretical predictions employing nucleon resonance degrees of freedom. A Legendre polynomial decomposition suggests this behavior could be related to the excitation of the d^{*}(2380) hexaquark.

International Nosocomial Infection Control Consortium (INICC) report, data summary of 45 countries for 2012-2017: Device-associated module

BACKGROUND

We report the results of International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2012 to December 2017 in 523 intensive care units (ICUs) in 45 countries from Latin America, Europe, Eastern Mediterranean, Southeast Asia, and Western Pacific.

METHODS

During the 6-year study period, prospective data from 532,483 ICU patients hospitalized in 242 hospitals, for an aggregate of 2,197,304 patient days, were collected through the INICC Surveillance Online System (ISOS). The Centers for Disease Control and Prevention-National Healthcare Safety Network (CDC-NHSN) definitions for device-associated health care-associated infection (DA-HAI) were applied.

RESULTS

Although device use in INICC ICUs was similar to that reported from CDC-NHSN ICUs, DA-HAI rates were higher in the INICC ICUs: in the medical-surgical ICUs, the pooled central line-associated bloodstream infection rate was higher (5.05 vs 0.8 per 1,000 central line-days); the ventilator-associated pneumonia rate was also higher (14.1 vs 0.9 per 1,000 ventilator-days,), as well as the rate of catheter-associated urinary tract infection (5.1 vs 1.7 per 1,000 catheter-days). From blood cultures samples, frequencies of resistance, such as of Pseudomonas aeruginosa to piperacillin-tazobactam (33.0% vs 18.3%), were also higher.

CONCLUSIONS

Despite a significant trend toward the reduction in INICC ICUs, DA-HAI rates are still much higher compared with CDC-NHSN's ICUs representing the developed world. It is INICC's main goal to provide basic and cost-effective resources, through the INICC Surveillance Online System to tackle the burden of DA-HAIs effectively.

Effectiveness of community-based DOTS strategy on tuberculosis treatment success rates in Namibia

<sec id="st1"> <title>SETTING</title> DOTS is a key pillar of the global strategy to end tuberculosis (TB). </sec> <sec id="st2"> <title>OBJECTIVE</title> To assess the effectiveness of community-based compared with facility-based DOTS on TB treatment success rates in Namibia. </sec> <sec id="st3"> <title>METHODS</title> Annual TB treatment success, cure, completion and case notification rates were compared between 1996 and 2015 using interrupted time series analysis. The intervention was the upgrading by the Namibian government of the TB treatment strategy from facility-based to community-based DOTS in 2005. </sec> <sec id="st4"> <title>RESULTS</title> The mean annual treatment success rate during the pre-intervention period was 58.9% (range 46-66) and increased significantly to 81.3% (range 69-87) during the post-intervention period. Before the intervention, there was a non-significant increase (0.3%/year) in the annual treatment success rate. After the intervention, the annual treatment success rate increased abruptly by 12.9% (P < 0.001) and continued to increase by 1.1%/year thereafter. The treatment success rate seemed to have stagnated at ∼85% at the end of the observation period. </sec> <sec id="st5"> <title>CONCLUSION</title> Expanding facility-based DOTS to community-based DOTS increased annual treatment success rates significantly. However, the treatment success rate at the end of the observation period had stagnated below the targeted 95% success rate. </sec>.

Integrating feral cat (Felis catus) control into landscape-scale introduced predator management to improve conservation prospects for threatened fauna: a case study from the south coast of Western Australia

Abstract ContextFeral cat predation has had a significant impact on native Australian fauna in the past 200 years. In the early 2000s, population monitoring of the western ground parrot showed a dramatic decline from the pre-2000 range, with one of three meta-populations declining to very low levels and a second becoming locally extinct. We review 8 years of integrated introduced predator control, which trialled the incorporation of the feral cat bait Eradicat® into existing fox baiting programs. AimsTo test the efficacy of integrating feral cat control into an existing introduced predator control program in an adaptive management framework conducted in response to the decline of native species. The objective was to protect the remaining western ground parrot populations and other threatened fauna on the south coast of Western Australia. MethodsA landscape-scale feral cat and fox baiting program was delivered across south coast reserves that were occupied by western ground parrots in the early 2000s. Up to 500000ha of national parks and natures reserves were baited per annum. Monitoring was established to evaluate both the efficacy of landscape-scale baiting in management of feral cat populations, and the response of several native fauna species, including the western ground parrot, to an integrated introduced predator control program. Key resultsOn average, 28% of radio-collared feral cats died from Eradicat® baiting each year, over a 5-year period. The results varied from 0% to 62% between years. Changes in site occupancy by feral cats, as measured by detection on camera traps, was also variable, with significant declines detected after baiting in some years and sites. Trends in populations of native fauna, including the western ground parrot and chuditch, showed positive responses to integrated control of foxes and cats. ImplicationsLandscape-scale baiting of feral cats in ecosystems on the south coast of Western Australia had varying success when measured by direct knockdown of cats and site occupancy as determined by camera trapping; however, native species appeared to respond favourably to integrated predator control. For the protection of native species, we recommend ongoing baiting for both foxes and feral cats, complemented by post-bait trapping of feral cats. We advocate monitoring baiting efficacy in a well designed adaptive management framework to deliver long-term recovery of threatened species that have been impacted by cats.

Forearm and biceps circumferential variations in skin tissue dielectric constant and firmness

Tissue dielectric constant (TDC) and skin firmness assessed via indentation force (FORCE) help quantify lymphedema and track changes. We sought to determine potential differences in these parameters dependent on arm circumferential locations. Thus, TDC and FORCE were measured in 40 healthy women at medial, anterior and lateral locations on forearm and biceps. In five other women with unilateral lymphedema (68.6±7.6 years), TDC was measured at corresponding circumferential forearm positions. Measurements were done in triplicate using compact noninvasive devices. Results for healthy women (23.8±2.7 years) showed forearm medial TDC values (26.7±2.2) were less than anterior (28.0±2.4) or lateral (28.0±2.5) positions (p<0.001). Lymphedema patients had elevated values but similar medialanterior- lateral patterns (33.7±8.0, 39.8±10.2 and 42.9±10.0). Biceps medial TDC values (24.1±2.2) were also less than either anterior (27.0±2.1) or lateral (28.2±3.3). Contrastingly, medial FORCE values at forearm and biceps were less than at anterior and lateral locations (p<0.001) and increased in the order of medialanterior- lateral on forearm (p<0.001). The present findings provide reference values for both TDC and FORCE of commonly measured arm sites with specificity as to circumferential variations. This observed variation indicates the need for care in locating measurement positions for tracking patients with lymphedema.

Cultivating Innovative Pragmatic Cluster-Randomized Registry Trials Embedded in Hemodialysis Care: Workshop Proceedings From 2018

Hemodialysis is a life-sustaining treatment for persons with kidney failure. However, those on hemodialysis still face a poor quality of life and a short life expectancy. High-quality research evidence from large randomized controlled trials is needed to identify interventions that improve the experiences, outcomes, and health care of persons receiving hemodialysis. With the support of the Canadian Institutes of Health Research and its Strategy for Patient-Oriented Research, the Innovative Clinical Trials in Hemodialysis Centers initiative brought together Canadian and international kidney researchers, patients, health care providers, and health administrators to participate in a workshop held in Toronto, Canada, on June 2 and 3, 2018. The workshop served to increase knowledge and awareness about the conduct of innovative, pragmatic, cluster-randomized registry trials embedded into routine hemodialysis care and provided an opportunity to discuss and build support for new trial ideas. The workshop content included structured presentations, facilitated group discussions, and expert panel feedback. Partnerships and promising trial ideas borne out of the workshop will continue to be developed to support the implementation of future large-scale trials.

The Frequency of Routine Blood Sampling and Patient Outcomes Among Maintenance Hemodialysis Recipients

RATIONALE & OBJECTIVE

Surveillance blood work is routinely performed in maintenance hemodialysis (HD) recipients. Although more frequent blood testing may confer better outcomes, there is little evidence to support any particular monitoring interval.

STUDY DESIGN

Retrospective population-based cohort study.

SETTING & PARTICIPANTS

All prevalent HD recipients in Ontario, Canada, as of April 1, 2011, and a cohort of incident patients commencing maintenance HD in Ontario, Canada, between April 1, 2011, and March 31, 2016.

EXPOSURE

Frequency of surveillance blood work, monthly versus every 6 weeks.

OUTCOMES

The primary outcome was all-cause mortality. Secondary outcomes were major adverse cardiovascular events, all-cause hospitalization, and episodes of hyperkalemia.

ANALYTICAL APPROACH

Cox proportional hazards with adjustment for demographic and clinical characteristics was used to evaluate the association between blood testing frequency and all-cause mortality. Secondary outcomes were evaluated using the Andersen-Gill extension of the Cox model to allow for potential recurrent events.

RESULTS

7,454 prevalent patients received care at 17 HD programs with monthly blood sampling protocols (n=5,335 patients) and at 8 programs with blood sampling every 6 weeks (n=2,119 patients). More frequent monitoring was not associated with a lower risk for all-cause mortality compared to blood sampling every 6 weeks (adjusted HR, 1.16; 95% CI, 0.99-1.38). Monthly monitoring was not associated with a lower risk for any of the secondary outcomes. Results were consistent among incident HD recipients.

LIMITATIONS

Unmeasured confounding; limited data for center practices unrelated to blood sampling frequency; no information on frequency of unscheduled blood work performed outside the prescribed sampling interval.

CONCLUSIONS

Monthly routine blood testing in HD recipients was not associated with a lower risk for death, cardiovascular events, or hospitalizations as compared with testing every 6 weeks. Given the health resource implications, the frequency of routine blood sampling in HD recipients deserves careful reassessment.

P1936Selective inhibition of the Mek1/2-Erk1/2 signalling pathway induces the differentiation of human cardiac pericyte-like cells into contractile vascular smooth muscle cells

Background

Arteriogenesis is key for tissue repair but whether myocardial stromal cells contribute to this phenomenon remains unknown.

Purpose

Investigate if cardiac pericytes are a druggable target for therapeutic arteriogenesis.

Methods and results

The localization of pericyte-like cells (PCs) was assessed in the human and murine heart by immunohistochemistry of typical antigenic markers. CD34+ PCs co-expressing NG2 and PDGFRβ but not endothelial cell (EC) or vascular smooth muscle cell (VSMC) antigens were identified in peri-arterial position in normal hearts. Interestingly, we also found rare PCs co-expressing αSMA in the peri-infarct myocardium, suggesting these cells could represent a transitory phenotype between PCs and VSMCs. Next, we isolated human cardiac PCs by immunosorting for CD31 and CD34 and established the purity of the isolated CD34+CD31- fraction by flow cytometry. Following culture expansion, cardiac PCs maintain the typical antigenic profile except for CD34. Moreover, we confirmed the PCs' ability to promote angiogenesis in-vitro. The withdrawal of EGF and bFGF from the culture media for 10 days induced the differentiation of PCs into mature VSMCs, as documented by a massive upregulation of contractile genes MYH11, CNN1 and ACTA2 (200-, 35- and 15-folds increase versus naïve PCs, p<0.01), which was followed by the induction of SM-MHC, Smoothelin B, αSMA, Calponin and SM22α proteins (p<0.05 versus PCs). In addition, PC-derived cells lost migratory capacity, secreted elastin, and responded to endothelin-1 in a contraction assay, thus phenocopying the behaviour of control coronary artery-derived VSMCs. We excluded contamination of the PC preparation by verifying similar phenomena occur in PCs expanded from single cell clonogeneic assays. Moreover, the process is partially reversible, with PC-derived VSMCs being able to reacquire some intermediate markers following EGF/bFGF re-challenge. ECs secrete EGF and bFGF, with this GF signalling being enhanced by hypoxia, suggesting ECs may control the PC phenotype in a paracrine fashion. Mechanistic studies revealed the Mek1/2-Erk1/2-Elk1 signalling is accountable for the transcriptional repression of VSMC genes in PCs. Accordingly, a selective Mek1/2 inhibitor (PD0325901) was able to switch the definitive VSMC phenotype of PCs maintained in full media. The drug prevented the phosphorylation of Erk1/2 and its downstream target Elk1. This likely relieves the complex SRF/MyocD and abolishes the transcriptional repression at the gene promoter.

Conclusions

Cardiac PCs have a VSMC potential which is under the inhibitory control of the Mek1/2-Erk1/2-Elk1 signalling. Mek1/2 inhibitors showed promises for the treatment of melanoma and solid tumours. A novel application of this class of compounds to improve arteriogenesis in myocardial ischemia is fascinating. The caveat about their potential cardiotoxicity could be less relevant with short duration treatments of myocardial ischemia.

Acknowledgement/Funding

British Heart Foundation Centre for Regenerative Medicine Award (II) - “Centre for Vascular Regeneration” (RM/17/3/33381)