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Background: Cardiomyopathy is the leading cause of death in Duchenne muscular dystrophy (DMD). Cardiac magnetic resonance (CMR) parametric mapping sequences offer insights into disease pathophysiology. We propose a novel approach by leveraging T2 mapping in conjunction with T1 and extracellular volume (ECV) mapping to perform a virtual myocardial biopsy. While previous work has attempted to describe myocardial changes in DMD, our inclusion of T2 mapping enables comprehensive categorization of myocardial tissue characteristics of fibrosis, edema, and fat to better understand the pathological composition of the myocardium with disease progression. Methods: DMD patients (n = 49; median: 12 years-old) underwent CMR, including T1, T2, and ECV. Categories were defined as normal, isolated high T1 (normal ECV, high T1, normal T2), fibrosis (high ECV, normal or high T1, normal T2), edema (normal or high ECV, normal or high T1, high T2), fat (normal ECV, low T1, high T2) or fibrofatty (high ECV, low T1, high T2). Results: Median left ventricular ejection fraction (LVEF) was 59% with 27% having LVEF < 55%. Those with normal LVEF and no late gadolinium enhancement (37%) were younger in age (10.5 ± 2.6 vs. 15.0 ± 4.3 years-old, p < 0.001). Native T1 was elevated in at least one slice in 82% of patients. Those with high T2 at any slice (27%) were older (p = 0.005) and had lower LVEF (p = 0.005) compared with subjects with normal T2 (73%). The most common myocardial characterization was fibrosis (43%) followed by isolated high T1 (24%). Of the 13 with high T2, ten were categorized as edema, two as fibrofatty, and one as fat. Conclusion: CMR parametric mapping sequences offer insights into Duchenne cardiomyopathy pathophysiology, which should drive development of therapeutic interventions aimed at these targets. Myocardial fibrosis is common in DMD. Patients with elevated T2 were older and had lower LVEF. Though fat infiltration was present, the majority of subjects with elevated T2 met criteria for myocardial edema. [ABSTRACT FROM AUTHOR]

Epidemiologists face a unique challenge in measuring risk relationships involving time-varying exposures in early pregnancy. Each week in early pregnancy is distinct in its contribution to fetal development, and this period is commonly characterized by shifts in maternal behavior and, consequently, exposures. In this simulation study, we used alcohol as an example of an exposure that often changes during early pregnancy and miscarriage as an outcome affected by early exposures. Data on alcohol consumption patterns from more than 5,000 women in the Right From the Start cohort study (United States, 2000–2012) informed measures of the prevalence of alcohol exposure, the distribution of gestational age at cessation of alcohol use, and the likelihood of miscarriage by week of gestation. We then compared the bias and precision of effect estimates and statistical power from 5 different modeling approaches in distinct simulated relationships. We demonstrate how the accuracy and precision of effect estimates depended on alignment between model assumptions and the underlying simulated relationship. Approaches that incorporated data about patterns of exposure were more powerful and less biased than simpler models when risk depended on timing or duration of exposure. To uncover risk relationships in early pregnancy, it is critical to carefully define the role of exposure timing in the underlying causal hypothesis. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the ability of concentration of anti-Müllerian hormone (AMH), antral follicle count (AFC), and concentration of follicle stimulating hormone (FSH) to predict the onset of menopause.Study Design: The Coronary Artery Risk Development in Young Adults Study (CARDIA) Women's Study was an ancillary study to CARDIA, a population-based study of adults aged 18-30 years followed for 3 decades. For this report, participants were women (n=426) who had attended the CARDIA year 15-16 (2000-2001) examination, had at least one ovary, were not pregnant, and underwent serum AMH and FSH measurement and transvaginal ultrasonography in 2002-2003.Main Outcome Measures: The probability of menopause in 5 years based upon AMH, FSH, and AFC.Results: The mean age of the women at the time of AMH, FSH, and AFC assessment was 43 years. The cumulative incidence of menopause at 25 years (or follow-up) was 27% (n=426), and the incidence within 5 years was 13% (n=55). Among women aged 45-49 years, undetectable AMH concentrations were associated with a greater than 60% probability of menopause within 5 years, whereas approximately 1/3 of women with no or just one antral follicle experienced menopause within 5 years. Both low and high concentrations of FSH were associated with greater odds of menopause than intermediate concentrations. Models with multiple markers did not improve the prediction of menopause over that afforded by models with single markers.Conclusion: The ability to predict onset of menopause was improved with any of the three menopausal markers in addition to age. AMH concentrations were more closely associated with menopause than AFC or FSH. [ABSTRACT FROM AUTHOR]

Background: Extracellular volume fraction (ECV) is altered in pathological cardiac remodeling and predicts death and arrhythmia. ECV can be quantified using cardiovascular magnetic resonance (CMR) T1 mapping but calculation requires a measured hematocrit (Hct). The longitudinal relaxation of blood has been used in adults to generate a synthetic Hct (estimate of true Hct) but has not been validated in pediatric populations. Methods: One hundred fourteen children and young adults underwent a total of 163 CMRs with T1 mapping. The majority of subjects had a measured Hct the same day (N = 146). Native and post-contrast T1 were determined in blood pool, septum, and free wall of mid-LV, avoiding areas of late gadolinium enhancement. Synthetic Hct and ECV were calculated and intraclass correlation coefficient (ICC) and linear regression were used to compare measured and synthetic values. Results: The mean age was 16.4 ± 6.4 years and mean left ventricular ejection fraction was 59% ± 9%. The mean measured Hct was 41.8 ± 3.0% compared to the mean synthetic Hct of 43.2% ± 2.9% (p < 0.001, ICC 0.46 [0.27, 0.52]) with the previously published model and 41.8% ± 1.4% (p < 0.001, ICC 0.28 [0.13, 0.42]) with the locally-derived model. Mean measured mid-free wall ECV was 30.5% ± 4.8% and mean synthetic mid-free wall ECV of local model was 29. 7% ± 4.6% (p < 0.001, ICC 0.93 [0.91, 0.95]). Correlations were not affected by heart rate and did not significantly differ in subpopulation analysis. While the ICC was strong, differences between measured and synthetic ECV ranged from -8. 4% to 4.3% in the septum and -12.6% to 15.8% in the free wall. Using our laboratory's normal cut-off of 28.5%, 59 patients (37%) were miscategorized (53 false negatives, 6 false positives) with published model ECV. The local model had 37 miscategorizations (20 false negatives, 17 false positives), significantly fewer but still a substantial number (23%). Conclusions: Our data suggest that use of synthetic Hct for the calculation of ECV results in miscategorization of individual patients. This difference may be less significant once synthetic ECV is calculated and averaged over a large research cohort, making it potentially useful as a research tool. However, we recommend formal measurement of Hct in children and young adults for clinical CMRs. [ABSTRACT FROM AUTHOR]

Background: Duchenne muscular dystrophy (DMD) cardiomyopathy is a progressive disease for which there is no cure. Disease-specific therapies are needed that can be initiated before irreversible myocardial damage ensues. In order to evaluate therapeutic efficacy, surrogate endpoints other than ejection fraction must be found. The hypothesis of this study is that T1 and extracellular volume fraction (ECV) mapping using cardiovascular magnetic resonance (CMR) can detect diffuse extracellular matrix expansion in DMD patients with normal left ventricular ejection fraction (LVEF) and without myocardial late gadolinium enhancement (LGE). Methods: Thirty-one DMD and 11 healthy control participants were prospectively enrolled. CMR using a modified Look-Locker (MOLLI) sequence was performed in all participants before and after contrast administration. T1 and ECV maps of the mid left ventricular myocardium were generated and regions of interest were contoured using the standard 6-segment AHA model. Global and segmental values were compared between DMD and controls using a Wilcoxon rank-sum test. Results: The DMD participants had significantly higher mean native T1 compared with controls (1045 ms vs 988 ms, p = 0.001). DMD participants with normal LVEF and without evidence of LGE also demonstrated elevated mean native T1 (1039 ms vs 988 ms, p = 0.002, and 1038 ms vs 988 ms, p = 0.011). DMD participants had a significantly greater mean ECV than controls (0.31 vs 0.24, p < 0.001), even in the settings of normal LVEF (0.28 vs 0.24, p < 0.001) and negative LGE (0.29 vs 0.24, p =0.001). Conclusions: DMD participants have elevated LV myocardial native T1 and ECV, even in the setting of normal LVEF and in the absence of LGE. T1 and ECV mapping in DMD have potential to serve as surrogate cardiomyopathy outcome measures for clinical trials. [ABSTRACT FROM AUTHOR]

BACKGROUND: The OxiMax N-600x containing SatSeconds alarm management software was designed to assist clinicians in discriminating nuisance alarms from those that are clinically relevant. Instead of sounding an alarm the moment the oxygen saturation reading violates the upper or lower limit settings, a magnitude and duration of tolerance can be set. The primary objective was to study the proportion of nuisance alarms relative to the proportion of clinically relevant alarms being filtered under 4 different SatSeconds alarm settings (ie, 10, 25, 50, and 100) in the neonatal intensive care environment. METHODS: This is an observational prospective study of 50 infants cared for in 3 large neonatal ICUs. Infants were monitored for 4 continuous h each by a study observer with the study monitor, in addition to standard multiparameter monitors. The performance of the SatSeconds alarm was compared with nursing intervention. RESULTS: The area under the receiver operating characteristic curve (95% CI) for SatSeconds alarm settings when compared with nursing intervention were as follows: 0.61 (0.57-0.66) when the SatSeconds alarm setting was off, 0.63 (0.59-0.68) for the 10 SatSeconds alarm setting, 0.64 (0.59-0.69) for the 25 SatSeconds alarm setting, 0.64 (0.59-0.69) for the 50 SatSeconds alarm setting, and 0.63 (0.58-0.68) for the 100 SatSeconds alarm setting, respectively. CONCLUSIONS: The SatSeconds feature of the OxiMax N-600x pulse oximeter reduced some nuisance alarms; however, its specificity to nurse-identified desaturation events does not significantly improve with lengthening SatSeconds alarm settings. [ABSTRACT FROM AUTHOR]

Background: Biochemical cervical change during labor is not well understood, in part, because of a dearth of technologies capable of safely probing the pregnant cervix in vivo. The need for such a technology is 2-fold: (1) to gain a mechanistic understanding of the cervical ripening and dilation process and (2) to provide an objective method for evaluating the cervical state to guide clinical decision-making. Raman spectroscopy demonstrates the potential to meet this need, as it is a noninvasive optical technique that can sensitively detect alterations in tissue components, such as extracellular matrix proteins, lipids, nucleic acids, and blood, which have been previously established to change during the cervical remodeling process.Objective: We sought to demonstrate that Raman spectroscopy can longitudinally monitor biochemical changes in the laboring cervix to identify spectral markers of impending parturition.Study Design: Overall, 30 pregnant participants undergoing either spontaneous or induced labor were recruited. The Raman spectra were acquired in vivo at 4-hour intervals throughout labor until rupture of membranes using a Raman system with a fiber-optic probe. Linear mixed-effects models were used to determine significant (P<.05) changes in peak intensities or peak ratios as a function of time to delivery in the study population. A nonnegative least-squares biochemical model was used to extract the changing contributions of specific molecule classes over time.Results: We detected multiple biochemical changes during labor, including (1) significant decreases in Raman spectral features associated with collagen and other extracellular matrix proteins (P=.0054) attributed to collagen dispersion, (2) an increase in spectral features associated with blood (P=.0372), and (3) an increase in features indicative of lipid-based molecules (P=.0273). The nonnegative least-squares model revealed a decrease in collagen contribution with time to delivery, an increase in blood contribution, and a change in lipid contribution.Conclusion: Our findings have demonstrated that in vivo Raman spectroscopy is sensitive to multiple biochemical remodeling changes in the cervix during labor. Furthermore, in vivo Raman spectroscopy may be a valuable noninvasive tool for objectively evaluating the cervix to potentially guide clinical management of labor. [ABSTRACT FROM AUTHOR]

OBJECTIVES: We conducted a randomized trial to test the hypothesis that mother's voice played through a pacifier-activated music player (PAM) during nonnutritive sucking would improve the development of sucking ability and promote more effective oral feeding in preterm infants. METHODS: Preterm infants between 34 0/7 and 35 6/7 weeks' postmenstrual age, including those with brain injury, who were taking at least half their feedings enterally and less than half orally, were randomly assigned to receive 5 daily 15-minute sessions of either PAM with mother's recorded voice or no PAM, along with routine nonnutritive sucking and maternal care in both groups. Assignment was masked to the clinical team. RESULTS: Ninety-four infants (46 and 48 in the PAM intervention and control groups, respectively) completed the study. The intervention group had significantly increased oral feeding rate (2.0 vs 0.9 mL/min, P< .001), oral volume intake (91.1 vs 48.1 mL/kg/d, P= .001), oral feeds/ day (6,5 vs 4.0, P < .001), and faster time-to-full oral feedings (31 vs 38 d, P = .04) compared with controls. Weight gain and cortisol levels during the 5-day protocol were not different between groups. Average hospital stays were 20% shorter in the PAM group, but the difference was not significant {P = .07). CONCLUSIONS: A PAM using mother's voice improves oral feeding skills in preterm infants without adverse effects on hormonal stress or growth. [ABSTRACT FROM AUTHOR]

Objective: To examine whether premenopausal reproductive age, as indicated by serum antimüllerian hormone (AMH), is associated with leukocyte aging biomarkers.Design: Prospective cohort analysis.Setting: The Coronary Artery Risk Development in Young Adults study, a population-based study of Black and White adults from four US communities (Birmingham, AL; Chicago, IL; Minneapolis, MN; Oakland, CA).Patient(s): Premenopausal women with serum AMH measures at examination year 15 as well as leukocyte aging markers.Intervention(s): None.Main Outcome Measure(s): Telomere length, mitochondrial deoxyribonucleic acid (mtDNA) copy number, and intrinsic and extrinsic epigenetic age acceleration (EAA) at examination years 15, 20, and 25 as well as change between examination years.Result(s): Women were 40.2 (standard deviation, 3.7) years of age at examination year 15 when the AMH and initial measures of telomere length and mtDNA copy number (n = 386) were obtained and EAA occurred. After adjustment for chronological age, race, and smoking history, AMH quartile at examination year 15 was not associated with telomere length at examination years 15 and 25 or telomere length change between these years, mtDNA copy number at examination years 15 and 25 or change between these years, or intrinsic EAA at examination years 15 and 20 or change between these years. Women in the second AMH quartile had faster extrinsic EAA than women in the lowest AMH quartile (β-coefficient, 1.84; 95% confidence interval, 0.20-3.49).Conclusion(s): In a population-based cohort, AMH did not have associations with leukocyte telomere length, mtDNA copy number, or intrinsic EAA. [ABSTRACT FROM AUTHOR]

Introduction: Demonstrating human papillomavirus vaccine impact is critical for informing guidelines to increase vaccination and decrease human papillomavirus‒related outcomes, particularly in states with suboptimal vaccination coverage, such as Tennessee. This study examines the trends in high-grade cervical lesion incidence among Tennessee Medicaid-enrolled women aged 18-39 years and the subset of women who were screened for cervical cancer.Methods: Using a validated claims-based model to identify incident cervical intraepithelial neoplasia Grades 2 or 3 or adenocarcinoma in situ events, annual age group‒specific incidence rates from Tennessee Medicaid billing data, 2008-2018, were calculated. Significant trends were determined by Joinpoint. Analyses were conducted in 2020.Results: From 2008 to 2018, high-grade cervical lesion incidence significantly declined in women aged 18-20 years (average annual percentage change= -31.9, 95% CI= -38.6, -24.6), 21-24 years (average annual percentage change= -12.9, 95% CI= -22.3, -2.4), and 25-29 years (average annual percentage change= -6.4, 95% CI= -8.1, -4.6). Among screened women, rates significantly declined for ages 18-20 years (average annual percentage change= -20.3, 95% CI= -25.3, -15.0), 21-24 years (average annual percentage change= -10.2, 95% CI= -12.6, -7.8), and 25-29 years (average annual percentage change= -2.6, 95% CI= -3.9, -1.2). Trends from 2008 to 2018 were stable for older age groups (30-34 and 35-39 years).Conclusions: Results show reductions in high-grade cervical lesion incidence among ages most likely to have benefited from the human papillomavirus vaccine. Declines among young, screened women suggest causes other than reduction in screening. Evidence of vaccine impact in populations with low-vaccination coverage, such as Tennessee, is promising. [ABSTRACT FROM AUTHOR]