Randomised clinical trial of Class II ART restoration in primary teeth with and without retentive grooves after 12 months

AIM

The aim of the study was to evaluate the survival of Class II ART (Atraumatic Restorative Treatment) restorations in primary molars using encapsulated glass ionomer in cavities with and without retentive grooves. A total of 293 Class II restorations were performed on primary molars by three trained operators, using ART hand instruments (SS White/Duflex, Rio de Janeiro, Brazil) and restored with EQUIA Fil (GC Corporation, Tokyo, Japan). One hundred eighty-seven children aged 3 to 7 years (mean age = 5.5) from two public schools located in Lima, Peru, were included in the study. The restorations were performed following the ART protocol, randomising the presence or absence of proximal retentions. Cavity cleaning and restoration times were recorded by the assistant using a digital chronometer. After 6 and 12 months, evaluations occurred following the ART criteria. Data were analysed using the Mann-Whitney, Chisquare and Fisher's exact tests, Kaplan-Meier survival and logarithmic range. The mean dmf-s of the participants was 21.6 (S.D. = 10.2). The mean times to clean the cavity and apply the restorative material were 5.4 and 6.6 minutes, respectively. Success rates after 6 and 12 months for restorations without retentive grooves were 90.3% and 77.2%, respectively; and with retentive grooves 95.9% and 91.8%, respectively. Statistically significant differences were found at the 12-month follow-up (p = 0.001). The proximal retentive grooves increased the survival rate of ART Class II restorations in primary teeth after 12 months of follow-up.

Monitoring storm evolution using a high-density seismic network

Data acquired by a dense seismic network deployed in the Cerdanya basin (Eastern Pyrenees) is used to track the temporal and spatial evolution of meteorological events such as rainfall episodes or thunderstorms. Comparing seismic and meteorological data, we show that for frequencies above 40 Hz, the dominant source of seismic noise is rainfall and hence the amplitude of the seismic data can be used as a proxy of rainfall. The interstation distance of 1.5 km provides an unprecedented spatial resolution of the evolution of rainfall episodes along the basin. Two specific episodes, one dominated by stratiform rain and the second one dominated by convective rain, are analyzed in detail, using high resolution disdrometer data from a meteorological site near one of the seismic instruments. Seismic amplitude variations follow a similar evolution to radar reflectivity values, but in some stratiform precipitation cases, it differs from the radar-derived precipitation estimates in this region of abrupt topography, where radar may suffer antenna beam blockage. Hence, we demonstrate the added value of seismic data to complement other sources of information such as rain-gauge or weather radar observations to describe the evolution of ground-level rainfall fields at high spatial and temporal resolution. The seismic power and the rainfall intensity have an exponential relationship and the periods with larger seismic power are coincident. The time intervals with rain drops diameters exceeding 3.5 mm do not result in increased seismic amplitudes, suggesting that there is a threshold value from which seismic data are no longer proportional to the size of the drops. Thunderstorms can be identified by the recording of the sonic waves generated by thunders, with. Single thunders detected to distances of a few tens of kilometers. As the propagation of these acoustic waves is expected to be strongly affected by parameters as air humidity, temperature variations or wind, the seismic data could provide an excellent tool to investigate atmospheric properties variations during thunderstorms.

Type III collagen formation is significantly associated with risk of outcome in HFpEF patients but loses its significant association with underlying AF

Introduction

Heart failure with preserved ejection fraction (HFpEF) is the most common type of heart failure, associated with high morbidity and mortality. Atrial fibrillation (AF) has been associated with structural remodelling and fibrosis and can coexist with HFpEF. Type III collagen is the second most abundant collagen in the heart wall and has been associated with cardiac fibrosis. It has been previously shown that type III collagen formation, measured by PRO-C3, is prognostic for all-cause mortality in HFpEF.

Purpose

In this study, we aimed at investigating if the prognostic power of PRO-C3 in relation to all-cause mortality would be affected by underlying AF in HFpEF patients.

Methods

The analysis included 166 individuals with hypertensive HFpEF. The patients were classified in three groups according to NYHA classification, 43.2% in NYHA Class II, 52.5% NYHA Class III and 2.5% NYHA Class IV. A previous history of AF was present in 53.4% of the patients. Cardiac function was assessed by echocardiography and standard clinical measures. Type III collagen formation was evaluated by means of ELISA with the biomarker PRO-C3, which targets the released N-terminal pro-peptide of type III collagen.

Results

Levels of PRO-C3 were significantly elevated in HFpEF patients with AF (p=0.0063). PRO-C3 was significantly predictive of all-cause mortality in HFpEF patients (AUC=0.643, p=0.0053), but lost its significant association when factoring in AF (AUC=0.581, p=0.235). There was an increased risk of all-cause mortality (p=0.0089) but not statistically significant differences in HFpEF patients with AF (p=0.178) with increasing tertiles of PRO-C3.

Conclusions

Type III collagen formation as measured by PRO-C3, was increased in patients with HFpEF and previously diagnosed AF. However, while PRO-C3 can be predictive of all-cause mortality in HFpEF patients, it lacks predicting ability when AF is considered. The presented data suggest a potential role of increased type III collagen formation in HFpEF patients with adverse outcomes, which is consistent with the presence of increased fibrosis, and can potentially be used as a tool of risk stratification.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Nordic Bioscience A/S

Clinical Correlates of Cardiac Conduction in Bipolar Disorder

Introduction

Patients with bipolar disorder (BD) have an increased risk for cardiovascular morbimortality. Clinical risk factors, specifically for arrhythmias and sudden cardiac death remain understudied.

Objectives

This study was conducted to assess differences in cardiac conduction among BD patients.

Methods

We included patients with BD in a cross-sectional design, confirmed by structured interview, age 18 through 80. Clinical characteristics were obtained using a structured questionnaire or medical records review. ECG intervals duration and morphology were manually assessed by cardiologists and compared among clinical subgroups using Chi-square, Mann-Whitney, and Kruskall-Wallis tests. Exploratory multivariable linear and logistic regression models were fitted to adjust for potential confounders.

Results

We included 117 patients (60.7% women, 76.9% bipolar I, 50% history of psychosis, 22.6% suicide attempts). We found a significantly longer QTc interval in BD patients with hypertension (difference: 9.5 ms, p=0.006), obesity (difference: 25 ms, p=0.001), and metabolic syndrome (difference: 13 ms, p=0.007). Hypertension remained a significant predictor of longer QTc after adjusting for age, gender, and antipsychotic use (estimate 17.718, p=0.018). We observed a significantly shorter PR interval in women (difference: 6 ms, p=0.029), early age of onset (difference 6 ms, p=0.025), non-users of lithium (difference 4 ms, p=0.002), and early trauma (difference 4 ms, p=0.038). Finally, we identified significant correlations between symptom severity, blood glucose and PR interval (r=0.298, p=0.001; r=0.278, p=0.003; respectively).

Conclusions

Patients with BD and hypertension may have an increased risk for QTc prolongation. Careful cardiovascular monitoring may be warranted.

Disclosure

No significant relationships.

Fibroblast growth factor homologous factors serve as a molecular rheostat in tuning arrhythmogenic cardiac late sodium current

Voltage-gated sodium (Nav1.5) channels support the genesis and brisk spatial propagation of action potentials in the heart. Disruption of NaV1.5 inactivation results in a small persistent Na influx known as late Na current (I Na,L), which has emerged as a common pathogenic mechanism in both congenital and acquired cardiac arrhythmogenic syndromes. Here, using low-noise multi-channel recordings in heterologous systems, LQTS3 patient-derived iPSCs cardiomyocytes, and mouse ventricular myocytes, we demonstrate that the intracellular fibroblast growth factor homologous factors (FHF1-4) tune pathogenic I Na,L in an isoform-specific manner. This scheme suggests a complex orchestration of I Na,L in cardiomyocytes that may contribute to variable disease expressivity of NaV1.5 channelopathies. We further leverage these observations to engineer a peptide-inhibitor of I Na,L with a higher efficacy as compared to a well-established small-molecule inhibitor. Overall, these findings lend insights into molecular mechanisms underlying FHF regulation of I Na,L in pathophysiology and outline potential therapeutic avenues.

AB0360 A DECADE OF SUSPECTED GIANT CELL ARTERITIS: CLINICAL FEATURES OF A HIGHLY HETEROGENEOUS DISEASE

Background:

Giant cell arteritis is the most common chronic systemic vasculitis in older adults. Permanent visual loss is the most concerning complication can occur in up to 20% of patients (1). Diagnosis is based on a combination of clinical findings, laboratory evidence of inflammatory markers, and temporal artery biopsy (TAB) confirming histologic evidence of inflammation. There are no definitive markers of the disease when TAB is negative.

Objectives:

The objective of this study was to illustrate the clinical features of subjects suspected with GCA evaluated at the Dallas Veterans Affairs Medical Center (VAMC) and identify those features that would differentiate between TAB positive GCA, TAB negative GCA and non-GCA patients.

Methods:

This retrospective study searched the Dallas VAMC database for subjects between January of 2010 until December 2019 with ICD-9 and ICD-10 entry code for GCA. Based on the 1990 ACR clinical classification criteria for GCA, suspected patients were classified as TAB positive GCA, TAB negative GCA and non-GCA. Subjects with incomplete data needed for classification were excluded. Group comparisons were performed with Fisher’s exact test for categorical variables and the Mann-Whitney test for continuous variables.

Results:

One-hundred and sixty-nine subjects had ICD-9/10 entry code for GCA. Ophthalmology was the specialty who did the initial evaluation in 46% of the suspected cases. Seventy-one patients were excluded due to incomplete data. Of the remaining 98 patients, 42 (42.9%) were diagnosed with GCA out of which 10 patients had a positive TAB. Seventy-six percent of patients diagnosed with GCA had negative temporal artery biopsies. In 56 (57.1%) patients GCA was ruled out (Figure 1). New-onset headache was the predominant symptom suggestive of GCA affecting 88.9% TAB positive and 100% of TAB negative cases compared to 56.6% of non-GCA patients (p< 0.001), followed by scalp tenderness in 33.3%, 58.1% and 10.9%, respectively (p< 0.001), jaw claudication in 57.1%, 34.5% and 14.9% (p=0.021), and elevated sedimentation rate in 33%, 65.6% and 33% (p=0.013) (Table 1). Polymyalgia rheumatica was present in 28.6% and 21.7% of patients diagnosed with GCA compared to zero percent in non-GCA cases (p=0.017). More than 30% of patients with GCA had normal acute phase reactants in this cohort.

Table 1.

Comparison of demographics and clinical features of patients with suspected GCA

GCA TAB Positive (n=10)GCA - TAB Negative (n=32)non-GCA (n=56)n%n%n%pAge (mean/sd)71.3 (7.8)67.3 (8.1)67.3 (8.9)0.367Male99030/3293.851/5691.10.885Clinical findingsNew onset headache8/988.932/3210030/5356.6<0.001Visual symptoms9/109022/3268.842/5477.80.351Jaw claudication4/757.110/2934.57/4714.90.021PMR2/728.65/2321.70/3000.017Scalp tenderness2/633.318/3158.15/4610.9<0.001Fever0/505/2321.72/355.70.117ESR > 501/333.321/3265.618/5433.30.013CRP > 101/333.35/3016.76/5411.10.473Anemia (hemoglobin < 12 g/ dl)2/728.615/3246.921/5240.40.642Thrombocytosis (platelets >400)2/728.63/329.44/517.80.228

Conclusion:

There is clinical heterogeneity within the patients diagnosed with GCA regardless of TAB. A high index of clinical suspicion needs to be the cornerstone of diagnosis. There is need for new classification criteria to include patients with negative TAB.

References:

[1]Soriano A, et al. Nat Rev Rheumatol. 2017 Aug;13(8):476-484.

Disclosure of Interests:

Adela Castro: None declared, Jiby Mathew: None declared, Ola Azzouqah: None declared, Jesus Diaz: None declared, Andreas Reimold Consultant of: Lilly, Grant/research support from: Abbvie

Pfizer

Gilead, Kyawt Shwin: None declared

Elementary mechanisms of calmodulin regulation of NaV1.5 producing divergent arrhythmogenic phenotypes

In cardiomyocytes, NaV1.5 channels mediate initiation and fast propagation of action potentials. The Ca2+-binding protein calmodulin (CaM) serves as a de facto subunit of NaV1.5. Genetic studies and atomic structures suggest that this interaction is pathophysiologically critical, as human mutations within the NaV1.5 carboxy-terminus that disrupt CaM binding are linked to distinct forms of life-threatening arrhythmias, including long QT syndrome 3, a "gain-of-function" defect, and Brugada syndrome, a "loss-of-function" phenotype. Yet, how a common disruption in CaM binding engenders divergent effects on NaV1.5 gating is not fully understood, though vital for elucidating arrhythmogenic mechanisms and for developing new therapies. Here, using extensive single-channel analysis, we find that the disruption of Ca2+-free CaM preassociation with NaV1.5 exerts two disparate effects: 1) a decrease in the peak open probability and 2) an increase in persistent NaV openings. Mechanistically, these effects arise from a CaM-dependent switch in the NaV inactivation mechanism. Specifically, CaM-bound channels preferentially inactivate from the open state, while those devoid of CaM exhibit enhanced closed-state inactivation. Further enriching this scheme, for certain mutant NaV1.5, local Ca2+ fluctuations elicit a rapid recruitment of CaM that reverses the increase in persistent Na current, a factor that may promote beat-to-beat variability in late Na current. In all, these findings identify the elementary mechanism of CaM regulation of NaV1.5 and, in so doing, unravel a noncanonical role for CaM in tuning ion channel gating. Furthermore, our results furnish an in-depth molecular framework for understanding complex arrhythmogenic phenotypes of NaV1.5 channelopathies.

Adrenergic CaV1.2 Activation via Rad Phosphorylation Converges at α1C I-II Loop

RATIONALE

Changing activity of cardiac CaV1.2 channels under basal conditions, during sympathetic activation, and in heart failure is a major determinant of cardiac physiology and pathophysiology. Although cardiac CaV1.2 channels are prominently upregulated via activation of PKA (protein kinase A), essential molecular details remained stubbornly enigmatic.

OBJECTIVE

The primary goal of this study was to determine how various factors converging at the CaV1.2 I-II loop interact to regulate channel activity under basal conditions, during β-adrenergic stimulation, and in heart failure.

METHODS AND RESULTS

We generated transgenic mice with expression of CaV1.2 α1C subunits with (1) mutations ablating interaction between α1C and β-subunits, (2) flexibility-inducing polyglycine substitutions in the I-II loop (GGG-α1C), or (3) introduction of the alternatively spliced 25-amino acid exon 9* mimicking a splice variant of α1C upregulated in the hypertrophied heart. Introducing 3 glycine residues that disrupt a rigid IS6-α-interaction domain helix markedly reduced basal open probability despite intact binding of CaVβ to α1C I-II loop and eliminated β-adrenergic agonist stimulation of CaV1.2 current. In contrast, introduction of the exon 9* splice variant in the α1C I-II loop, which is increased in ventricles of patients with end-stage heart failure, increased basal open probability but did not attenuate stimulatory response to β-adrenergic agonists when reconstituted heterologously with β2B and Rad or transgenically expressed in cardiomyocytes.

CONCLUSIONS

Ca2+ channel activity is dynamically modulated under basal conditions, during β-adrenergic stimulation, and in heart failure by mechanisms converging at the α1C I-II loop. CaVβ binding to α1C stabilizes an increased channel open probability gating mode by a mechanism that requires an intact rigid linker between the β-subunit binding site in the I-II loop and the channel pore. Release of Rad-mediated inhibition of Ca2+ channel activity by β-adrenergic agonists/PKA also requires this rigid linker and β-binding to α1C.

Early and midterm outcomes after transaxillar versus transfemoral TAVI. data from the spanish TAVI registry

 

Transaxillary access (TAx) has emerged as a less invasive alternative access when transfemoral access (TF) is not possible in patients undergoing TAVI. The primary endpoint of this study was to compare total in-hospital and 30-day mortality of patients included in the Spanish TAVI registry that were treated by TAx versus TF access.

Methods

All patients included in the Spanish TAVI registry who were treated by TAx or TF access were analyzed. In-hospital and 30-days outcomes were assessed using the Valve Academic Research Consortium definitions. An analyses by propensity score matching and multilevel logistic regression was performed for comparing both groups.

Results

A total of 6603 patients were included, of whom 191 (2.9%) were treated by TAx and 6412 were treated with TF access. After the adjustment, the device success was similar between both groups (94%, TAx vs 95%, TF p=0.95) as well as the rate of vascular complications (11.9% Tax vs 11.9 TF; p=0.78), bleeding (7.7% TAx vs. 7.9% TF; p=0.62) and stroke (4.2% TAx vs. 2.0 TF; p=0.09). However, in-hospital and 30-day mortality was significantly higher in TAx access group versus TF 2.19 (1.13–4.26): p=0.02 and 2.11 (1.08–4, 13); P=0.02, respectively. Similarly, the rate of acute myocardial infarction 5.05 (1.94–13.1); p=0.001, renal complications 2.07 (1.19–3.60; p =) 0.01 and pacemaker implantation 1.56 (1.01–2.40); p=0.04 was higher in the TAx group versus TF.

Conclusions

Transaxillary access compared to transfemoral access is associated with an increase in total in-hospital and 30-day mortality, as a result TAx access should be considered only in those cases in which TF is not possible

Funding Acknowledgement

Type of funding source: None

Fibroblast growth factor homologous factors tune arrhythmogenic late NaV1.5 current in calmodulin binding-deficient channels

The Ca2+-binding protein calmodulin has emerged as a pivotal player in tuning Na+ channel function, although its impact in vivo remains to be resolved. Here, we identify the role of calmodulin and the NaV1.5 interactome in regulating late Na+ current in cardiomyocytes. We created transgenic mice with cardiac-specific expression of human NaV1.5 channels with alanine substitutions for the IQ motif (IQ/AA). The mutations rendered the channels incapable of binding calmodulin to the C-terminus. The IQ/AA transgenic mice exhibited normal ventricular repolarization without arrhythmias and an absence of increased late Na+ current. In comparison, transgenic mice expressing a lidocaine-resistant (F1759A) human NaV1.5 demonstrated increased late Na+ current and prolonged repolarization in cardiomyocytes, with spontaneous arrhythmias. To determine regulatory factors that prevent late Na+ current for the IQ/AA mutant channel, we considered fibroblast growth factor homologous factors (FHFs), which are within the NaV1.5 proteomic subdomain shown by proximity labeling in transgenic mice expressing NaV1.5 conjugated to ascorbate peroxidase. We found that FGF13 diminished late current of the IQ/AA but not F1759A mutant cardiomyocytes, suggesting that endogenous FHFs may serve to prevent late Na+ current in mouse cardiomyocytes. Leveraging endogenous mechanisms may furnish an alternative avenue for developing novel pharmacology that selectively blunts late Na+ current.

Indicators to monitor policy progress in health adaptation to climate change: do they really do the job?

There is a need for urgent adaptive action to protect human health against climate change. Overall assessments based on a selection of indicators suggest that we are unable to cope with current climate impacts on health and unprepared to respond to increased pressures on climate-sensitive exposures and outcomes.

The health sector has been addressing climate adaptation to health, through siloed approaches limited to the health system, which reduces their capacity and effectiveness. Successful strategies for addressing climate and environmental degradation challenges to health, and related issues such as environmental health, nutrition or equity, require integrated adaptation approaches among the health systems, social protection systems, water and sanitation systems, urban planning, environmental health and climate services among others. For example, integrated monitoring and surveillance (human-animal-environmental-ecosystems health) is critical for the early identification of emerging risks, diseases or trends, and for resource planning and evaluation of the adaptation and control strategies. In addition, when climate and health indicators are put to use for prevention, and eventually adaptation, they are also frequently used in isolation, disregarding interactions. For example, early warning systems for the prevention of climate-influenced impacts on health, such as Heat Health Action Plans, air pollution warnings or allergenic pollen information systems are usually activated individually commonly fail to address the synergies across various climate-related or climate-aggravated exposures. Since various of those exposures tend to occur concurrently (e.g. heat, anthropogenic air pollution from thermal inversions, and Saharan dust intrusions), failure to integrate them in prevention efforts could affect their effectiveness and reach. Thus, there is a need to carry out an integrative approach for the multiple effects that climate change has on population health.

CaV channels reject signaling from a second CaM in eliciting Ca2+-dependent feedback regulation

Calmodulin (CaM) regulation of voltage-gated calcium (Ca_V1-2) channels is a powerful Ca²⁺-feedback mechanism to adjust channel activity in response to Ca²⁺ influx. Despite progress in resolving mechanisms of CaM-Ca_V feedback, the stoichiometry of CaM interaction with Ca_V channels remains ambiguous. Functional studies that tethered CaM to Ca_V1.2 suggested that a single CaM sufficed for Ca²⁺ feedback, yet biochemical, FRET, and structural studies showed that multiple CaM molecules interact with distinct interfaces within channel cytosolic segments, suggesting that functional Ca²⁺ regulation may be more nuanced. Resolving this ambiguity is critical as CaM is enriched in subcellular domains where Ca_V channels reside, such as the cardiac dyad. We here localized multiple CaMs to the Ca_V nanodomain by tethering either WT or mutant CaM that lack Ca²⁺-binding capacity to the pore-forming α-subunit of Ca_V1.2, Ca_V1.3, and Ca_V2.1 and/or the auxiliary β_2A subunit. We observed that a single CaM tethered to either the α or β_2A subunit tunes Ca²⁺ regulation of Ca_V channels. However, when multiple CaMs are localized concurrently, Ca_V channels preferentially respond to signaling from the α-subunit-tethered CaM. Mechanistically, the introduction of a second IQ domain to the Ca_V1.3 carboxyl tail switched the apparent functional stoichiometry, permitting two CaMs to mediate functional regulation. In all, Ca²⁺ feedback of Ca_V channels depends exquisitely on a single CaM preassociated with the α-subunit carboxyl tail. Additional CaMs that colocalize with the channel complex are unable to trigger Ca²⁺-dependent feedback of channel gating but may support alternate regulatory functions.

A new integrative perspective on early warning systems for health in the context of climate change

Climate change causes or aggravates a wide range of exposures with multiple impacts on health, both direct and indirect. Early warning systems have been established to act on the risks posed by these exposures, permitting the timely activation of action plans to minimize health effects. These plans are usually activated individually. Although they show good results from the point of view of minimizing health impacts, such as in the case of high temperature plans, they commonly fail to address the synergies across various climate-related or climate-aggravated exposures. Since several of those exposures tend to occur concurrently, failure to integrate them in prevention efforts could affect their effectiveness and reach. Thus, there is a need to carry out an integrative approach for the multiple effects that climate change has on population health. This article presents a proposal for how these plans should be articulated. The proposed integrated plan would consist of four phases. The first phase, based on early warning systems, would be the activation of different existing individual plans related to the health effects that can be caused by certain circumstances and when possible corrective measures would be implemented. The second phase would attempt to quantify the health impact foreseen by the event in terms of the different health indicators selected. The third phase would be to activate measures to minimize the impact on health, via population alerts and advisories, and additional social and health services, based on the provisions in phase two. Phase four would be related to epidemiological surveillance that permits evaluation of the effects of activating the plan. We believe that this integrative approach should be extended to all of the public health interventions related to climate change.

0391 Gateways, Disparities, and Finals Week, Oh My! Translating Sleep Science from the Laboratory to the Classroom

Introduction

Organic chemistry can be an insurmountable “gateway” course for otherwise-qualified students in pre-health pathways. Recent data indicate that organic chemistry increases drop-out risk for females and underrepresented minority students (URMs), raising the provocative possibility that sleep disparities are an underrecognized contributor to achievement gaps in gateway STEM courses.

Methods

In Study 1, 481 students enrolled in organic chemistry courses completed sleep questionnaires at the beginning, midpoint, and end of the semester. In Study 2, non-chemistry majors were randomly assigned to normal sleep (8 hours) or sleep restriction (5.5 hours) before taking an organic chemistry virtual lecture and test. In Study 3, 35 students wore actigraphy for five nights and could earn extra credit on a mid-semester test by averaging ≥8 hours of sleep; actigraphy sleep durations were compared to 40 active-control students who only received sleep education.

Results

In Study 1 (classroom), URM and female students earned lower organic chemistry grades than comparison students, p&lt;.001. Baseline weekday sleep duration predicted test grades across the semester, and students who improved their weekday sleep subsequently improved their organic chemistry grades. In Study 2 (laboratory), mild sleep loss impaired meta-cognitive judgments of organic chemistry learning, a potential causal mechanism for reduced persistence in chemistry courses. In Study 3 (classroom), when better sleep behaviors were incentivized by extra credit, students slept an hour longer/night than control groups (7.8 vs 6.8 hours, p&lt;.001). These benefits persisted 1 month later into finals week when sleep behaviors were not externally incentivized (7.3 vs 6.3 hours, p=.001). Improving sleep improved performance on difficult short answer questions after correcting for pre-final grades (Madjusted=78% vs 72%, p=.04).

Conclusion

Sleep disparities contribute to achievement gaps in gateway STEM courses, but incentives can reverse poor sleep habits. University administrators should develop and implement behavioral change programs to reduce sleep disparities.

Support

National Science Foundation (DRL 1920730)

0101 Episodic Future Thinking Triggers Age-Related Differences in Spindles and Slow Oscillations

Introduction

In young adults, sleep spindles are theorized to represent memory consolidation. Spindle density may be especially prominent when young adults encode information that has future relevance. Older adults, on the other hand, show reduced capacity for future thinking and deficits in sleep-dependent memory consolidation. To advance these literatures, we investigated whether the process of mentally simulating the future (versus remembering the past) was associated with subsequent alterations to sleep microarchitecture in young and older adults.

Methods

64 healthy adults aged 18–84 completed a polysomnography adaptation night followed by two in-laboratory experimental nights. On both nights, participants completed the Modified Future Crovitz Test (MFCT) in which they mentally simulated only future events or remembered only past events (night order counterbalanced). To quantify the extent of future/past thinking, we conducted linguistics analyses on tense (future/past) using LIWC 2015 software.

Results

On the future-thinking night, young adults with greater future-tense MFCT scores showed significantly greater spindle density across frontal, midline, and central sites (r=.42 to r=.51), even when controlling for age, gender, and total word count (all ps &lt; .01). The opposite was true for middle-to-older aged adults; greater future-tense MFCT scores were associated with less spindle density across midline and central sites after controlling for age, gender, and word count (r=-.44 to r=-.46, ps&lt;.05). However, while spindle density decreased, frontal slow oscillations increased in older adults with greater future-tense MFCT scores (r=.39, p&lt;.05). On the past-thinking night, spindle density and slow oscillations were unrelated to past-tense or future-tense MFCT scores for either age group.

Conclusion

Age-related deficits in memory consolidation may be due to impaired tagging of information as having future relevance, or impaired physiological responses during sleep to wake-based tagging. Addressing encoding—spindle interactions may inform why cognitive functioning declines in some adults more than others.

Support

Sleep Research Society Foundation

PSX-33 Effect of supplementing different proportions of sericea lespedeza with alfalfa silage on intake, digestibility, and nitrogen balance in sheep

Dietary manipulations to include tannins can change the proportion and amounts of N excreted in the urine and feces as well as improve N-use efficiency in ruminants. This study was conducted to investigate effects on animal digestion parameters of adding different proportions of sericea lespedeza hay (SL) to alfalfa silage. Alfalfa was harvested in June 2018 at 75% bloom, chopped, and then packed at 55% moisture into plastic-lined bins and allowed to ensile for 3 months. Alfalfa silage was either offered alone or mixed with 9, 18, or 27% SL on a DM basis. These diets were offered randomly for ad libitum consumption to 16 ewes (41.8 ± 4.61 kg BW) in a randomized complete block design experiment with 2 periods to provide 4 observations per treatment per experimental period, each consisting of a 14-d dietary adaptation period followed by 5 d of total fecal and urine collection. Data were analyzed using PROC MIXED of SAS and orthogonal linear and quadratic trend analyses were tested. Digestibility (%) of DM and OM and digestible DM and OM intake (g/kg BW) decreased linearly (P &lt; 0.05) with increasing SL addition to the diet. Digestibility of NDF and ADF decreased linearly (P &lt; 0.01) with increasing SL, and apparent absorption (%) of N decreased linearly (P &lt; 0.05) with increasing SL in the diet. Urinary N excretions (g/d) tended (P = 0.10) to decrease linearly while fecal N (g/day) tended to increase (P = 0.10) linearly with increasing SL proportion in the diet. In this study, supplementation with sericea lespedeza as a tannin source to alfalfa silage decreased forage digestibility and digestible organic matter intake and did not positively influence nitrogen use. The study was supported in part by USDA-ARS specific cooperative agreement 58-3655-4-052 and by USDA NIFA grant 2018-67019-27804.

European Space Agency experiments on thermodiffusion of fluid mixtures in space

This paper describes the European Space Agency (ESA) experiments devoted to study thermodiffusion of fluid mixtures in microgravity environment, where sedimentation and convection do not affect the mass flow induced by the Soret effect. First, the experiments performed on binary mixtures in the IVIDIL and GRADFLEX experiments are described. Then, further experiments on ternary mixtures and complex fluids performed in DCMIX and planned to be performed in the context of the NEUF-DIX project are presented. Finally, multi-component mixtures studied in the SCCO project are detailed.

Do active assist transfer devices improve transfer safety for patients and caregivers in hospital and community settings? A scoping review

Background: Safe patient handling practices reduce injury risk for healthcare workers (HCW) and patients, but may conflict with goals of rehabilitation and person-centred care by minimizing (a) active participation in transfers and (b) autonomy and dignity while using mechanical lifts. Active assist transfer devices (AATDs) have potential to address both safety and support needs for appropriate clients.Purpose: What is the scope and nature of the evidence to support the use of AATD for improving transfer safety for patients and caregivers in both hospital and community settings?Methods: Scoping review of peer-reviewed and Gray literature, using systematic search strategies and multiple reviewers for identifying papers and extracting data.Findings: Twenty-nine peer-reviewed publications, and 12 other documents (policy, technical) were included in the review. Half focused on HCW safety in the hospital setting, with only seven addressing patient safety in the community. Generally, literature was of low quality, with no controlled trials to support the benefit of this equipment, and often represented a nursing care perspective. However, positive outcomes reported included safety, satisfaction, and equipment utilization.Implications: There is a need for rigorous research on use of AATDs in the community comparing rehabilitation outcomes across other forms of transfer equipment. Other important targets include injury risk for family caregivers, and potential to support early discharge. At present, utilization of AATDs within the rehabilitation field will continue to rely on best judgement of the care team. Implementation of AATDs should be considered a compelling target for practice-based research and quality improvements.Implications for rehabilitationThe use of active assist transfer devices is associated with their availability in the in-patient hospital setting.The use of active assist transfer devices is associated with positive patient experience, such as increased patient satisfaction and dignity. Improved patient adherence and cooperation with healthcare workers during mobilization and rehabilitation may follow.Most current evidence is focused on caregiver safety outcomes and is in support of decreased injury rates with increased active assist transfer device use. There is a limited amount of evidence focusing on the rehabilitation outcomes with active assist transfer device use.With current evidence, the use of AATDs should be used at the discretion of the care team.

Effects on daily mortality of droughts in Galicia (NW Spain) from 1983 to 2013

Climate change scenarios indicate an increase in the intensity and frequency of droughts in several regions of the world in the 21st century, especially in Southern Europe, highlighting the threat to global health. For the first time, a time-series diagnostic study has been conducted regarding the impact of droughts in Galicia, a region in north-western Spain, on daily natural-cause mortality, daily circulatory-cause mortality, and daily respiratory-cause mortality, from 1983 to 2013. We analysed the drought periods over the area of interest using the daily Standardized Evapotranspiration-Precipitation Index (SPEI) and the daily Standardized Precipitation Index (SPI), obtained at various timescales (1, 3, 6, 9 months), to identify and classify the intensity of drought and non-drought periods. Generalized linear models with the Poisson regression link were used to calculate the Relative Risks (RRs) of different causes of mortality, and the percentage of Attributable Risk Mortality (%AR) was calculated based on RRs data. According to our findings, there were statistically significant (p < 0.05) associations between drought periods, measured by both the daily SPEI and SPI, and daily mortality in all provinces of Galicia (except Pontevedra) for different timescales. Furthermore, drought periods had a greater influence on daily mortality in the interior provinces of Galicia than in the coastal regions, with Lugo being the most affected. In short term, the effect of droughts (along with heatwaves) on daily mortality was observed in interior regions and was mainly explained by atmospheric pollution effect throughout 2000 to 2009 period in Ourense, being respiratory causes of mortality the group most strongly associated. The fact that droughts are likely to become increasingly frequent and intense in the context of climate change and the lack of studies that have considered the impact of droughts on specific causes of mortality make this type of analysis necessary.

The impact of advanced practice providers on the surgical resident experience: Agree to disagree?

BACKGROUND

We examined and compared APP versus surgical resident perceptions of the role of APPs in surgical subspecialty teams.

METHODS

Residents/first year surgical critical care fellows and inpatient service-specific APPs responded to a survey that examined perceptions about the APP-resident/fellow relationship. Statistical analysis compared responses using a Pearson chi-square test.

RESULTS

Thirty-two resident/fellows (48%) and 10 APPs (42%) responded. There was consensus that having an APP on service decreases workload, contributes to continuity of care and enhances resident-patient coordination education and agreement that there was clear communication and adequate collaboration. Both groups differed with respect to APPs contribution to resident/fellow clinical education, role definition and chain of command. The majority of trainees felt that APPs function at a PGY2 level (51.7%) compared to APPs, who felt that they functioned at a PGY4/5 (22%) or Fellow (44%) level.

CONCLUSION

APPs and resident/fellows agree that APPs impact resident workload, continuity of care and patient-coordination education.

Ristocetin and Botrocetin Involve Two Distinct Domains of von Willebrand Factor for Binding to Platelet Membrane Glycoprotein lb

We have evidence that ristocetin and botrocetin mediate binding of von Willebrand Factor (vWF) to platelet glycoprotein lb (GPIb) through two distinct domains on the vWF molecule. This was established by using monoclonal antibodies (MAbs) to vWF and synthetic peptides derived from the sequence of vWF. MAb 322 and MAb NMC/vW 4 both recognize native vWF as well as fragments containing the GPIb-binding domain of vWF, obtained with the following enzymes: trypsin (116 kDa), V-8 pro tease (Spill, 320 kDa) and V-8 protease plus subtilisin (33-28 kDa). Nevertheless, the lack of reciprocal displacement between the two MAbs in experiments of competitive inhibition for binding to vWF demonstrate that their respective epitopes are separate. Both MAbs inhibit 125I-vWF binding to platelet membrane GPIb and vWF-dependent platelet agglutination induced by ristocetin. However, only MAb NMC/vW4 inhibits these functions in the presence of botrocetin and when ristocetin-induced platelet agglutination is inhibited by MAb 322, botrocetin is still able to restore the agglutination. The involvement of two distinct domains of vWF for binding to GPIb in the presence of ristocetin or botrocetin was confirmed in experiments of binding of 125I-vWF to platelets using as competitor synthetic peptides corresponding to the GPIb binding domain of vWF (Cys 474 to Pro 488 and Ser 692 to Pro 708). At a final concentration of 2.5 mM both peptides inhibit more than 90% of the binding of vWF to ristocetin-treated platelets but are unable to modify this binding in the presence of botrocetin. In conclusion our data suggest that botrocetin and ristocetin involve distinct sites on vWF for binding to GPIb.

Abstract P2-02-12: Cell free DNA analysis identifies actionable ERBB2 amplifications in patients with HER2 negative breast cancer

Identification of ERBB2 (HER2) overexpression in metastatic breast cancer informs utilization of HER2 targeted therapy. The NCCN recommends HER2 expression re-evaluation at the first disease recurrence in patients with negative or equivocal tissue status given results discrepancies due to inadequate tissue biopsy, tumoral heterogeneity, biopsy technique or fixation as well as discordance in ERBB2 (HER2) expression between primary and metastatic lesions. We examined the incidence of ERBB2 (HER2) negative to positive “flips” (e.g. to ERBB2-amplified in plasma) in a cohort of patients who underwent a blood-based cell-free DNA (cfDNA) assay at a CLIA-certified/CAP-accredited/NYSDOH-approved molecular diagnostic laboratory.

Laboratory database was queried for samples from patients with a breast cancer diagnosis. The query was filtered to ensure patients with multiple cfDNA timepoints were counted only once. Patients without a pathology report submitted at any cfDNA collection timepoint or the pathology report did not include ERBB2 (HER2) status, results were inconclusive or quantity not sufficient were excluded. Between March 2014 and April 2017, 1,853 unique patients were identified with reported ERBB2 (HER2) status. For patients with more than one cfDNA timepoint collected (N=349; 18.8%), the earliest pathology report was referenced. 1,386 patient tumor samples were negative for HER2 overexpression (74.8%), 325 (17.5%) were positive, and 142 (7.7%) were equivocal. Twenty-nine of the 1,386 patients with reported tumor negative HER2 status had amplification on subsequent cfDNA analysis (2.1%).

All 29 patients were female. Most patients (N=21) had a single cfDNA timepoint collected. Median age at cfDNA blood draw was 58 years (range 28–68). Median length of time between reported tissue negative status and cfDNA blood draw was 405 days (range 21–4,060). Median plasma ERBB2 copy number was 2.44 (greater than 50th-centile per laboratory data) (range 2.15–16.5).

Clinical follow-up was obtained for 19 patients (65%). Nine patients were lost to follow-up or succumbed to disease prior to initiation of a new therapeutic regimen. One patient was known HER2 positive prior to receipt of the cfDNA results. In the remaining nine patients, six initiated targeted HER2 therapy following receipt of the cfDNA results, with five of six (83%) demonstrating a clinical response. In one patient with known ER/PR positive, HER2 negative disease, progressing through multiple lines of therapy, addition of trastuzumab and pertuzumab to her paclitaxel regimen following identification of the cfDNA ERBB2 amplification resulted in a significant reduction in CEA levels (238 to 37.9 ng/mL) by week five. In a second patient, following identification of the cfDNA ERBB2 amplification, she was treated with trastuzumab and pertuzumab along with docetaxel and had a dramatic response. She continues on trastuzumab and pertuzumab alone.

Although a modest sample size, this is the second cfDNA series demonstrating that ERBB2 (HER2) status may flip from negative to positive upon recurrence or metastasis, and that targeting plasma-detected ERBB2 amplification with anti-HER2 has clinical benefit. cfDNA is a viable alternative to tissue rebiopsy in this patient population.

Citation Format: Raymond VM, Diaz J, Banks KC, Ahn E, Brufsky A, Ellis M, Lippman M, Lee C, Pluard T, Schreeder M, Schwab R, Lanman RB. Cell free DNA analysis identifies actionable ERBB2 amplifications in patients with HER2 negative breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-02-12.

Ability of a Generalist Seed Beetle to Colonize an Exotic Host: Effects of Host Plant Origin and Oviposition Host

The colonization of an exotic species by native herbivores is more likely to occur if that herbivore is a generalist. There is little information on the life-history mechanisms used by native generalist insects to colonize exotic hosts and how these mechanisms are affected by host properties. We examined the ability of the generalist seed beetle Stator limbatus Horn to colonize an exotic species. We compared its host preference, acceptability, performance, and egg size when ovipositing and developing on two native (Pithecellobium dulce (Roxb.) Benth and Senegalia riparia (Kunth)) and one exotic legume species (Leucaena leucocephala (Lam.)). We also analyzed the seed chemistry. We found that females recognize the exotic species as an unfavorable host for larval development and that they delayed oviposition and laid fewer and larger eggs on the exotic species than on the native species. Survivorship on the exotic host was 0%. Additionally, seeds of the native species contain five chemical compounds that are absent in the exotic species, and the exotic species contains three sterols, which are absent in the native legumes. Genetically based differences between beetles adapted to different hosts, plastic responses toward new hosts, and chemical differences among seeds are important in host colonization and recognition of the exotic host. In conclusion, the generalist nature of S. limbatus does not influence its ability to colonize L. leucocephala. Explanations for the colonization of exotic hosts by generalist native species and for the success of invasive species must be complemented with studies measuring local adaptation and plasticity.