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Current Caltrans Standard Specifications for rubberized hot mix asphalt–gap-graded (RHMA-G) do not allow the inclusion of reclaimed asphalt pavement (RAP). This report summarizes the research conducted by the UCPRC in support of the Caltrans-industry initiative “10% RAP in RHMA-G,” whose goal is to evaluate the use of up to 10% RAP (by aggregate replacement) in RHMA-G mixes, provided that the research does not identify significant potential problems for durability. Five pilot projects were built by Caltrans as part the initiative. In each of the pilots, a control RHMA-G (without RAP) and an RHMA-G with 10% RAP were placed. The mixes were sampled during production and tested using performance-related tests at the UCPRC laboratory. The results of the testing of the mixes—including stiffness, four-point bending fatigue resistance, and rutting resistance—indicate that the addition of 10% RAP had minor effects on the mechanical properties of the RHMA-G. With just a few exceptions related to changes in the total binder content of the mix, the effect of the RAP addition was negligible compared with project-to-project differences. Modeling with CalME software based on four-point bending testing results indicated that the impact of the RAP addition on the cracking performance of the pavement was either negligible or comparable to project-to-project differences. From the constructability point of view, the addition of the RAP did not create any problems. The life cycle assessment presented in this report indicates that the addition of 10% RAP to the RHMA-G can reduce the greenhouse gasses emissions associated with the RHMA-G production (cradle-to-gate) by up to 5%.

BACKGROUND: We analyzed post-radiation (RT) neurocognitive outcomes in an ethnically diverse pediatric brain tumor population undergoing photon radiotherapy (XRT) and proton radiotherapy (PRT). PROCEDURE: Post-RT neurocognitive outcomes from 49 pediatric patients (37% Hispanic/Latino) with primary brain tumors were analyzed. Tests included cognitive outcomes, behavioral outcomes, and overall intelligence. For each outcome, proportion of patients with cognitive impairment (scores

Mitophagy, a mitochondria-specific form of autophagy, removes dysfunctional mitochondria and is hence an essential process contributing to mitochondrial quality control. PTEN-induced kinase 1 (PINK1) and the E3 ubiquitin ligase Parkin are critical molecules involved in stress-induced mitophagy, but the intracellular signaling mechanisms by which this pathway is regulated are unclear. We tested the hypothesis that signaling through RhoA, a small GTPase, induces mitophagy via modulation of the PINK1/Parkin pathway as a protective mechanism against ischemic stress. We demonstrate that expression of constitutively active RhoA as well as sphingosine-1-phosphate induced activation of endogenous RhoA in cardiomyocytes result in an accumulation of PINK1 at mitochondria. This is accompanied by translocation of Parkin to mitochondria and ubiquitination of mitochondrial proteins leading to recognition of mitochondria by autophagosomes and their lysosomal degradation. Expression of RhoA in cardiomyocytes confers protection against ischemia, and this cardioprotection is attenuated by siRNA-mediated PINK1 knockdown. In vivo myocardial infarction elicits increases in mitochondrial PINK1, Parkin, and ubiquitinated mitochondrial proteins. AAV9-mediated RhoA expression potentiates these responses and a concurrent decrease in infarct size is observed. Interestingly, induction of mitochondrial PINK1 accumulation in response to RhoA signaling is neither mediated through its transcriptional upregulation nor dependent on depolarization of the mitochondrial membrane, the canonical mechanism for PINK1 accumulation. Instead, our results reveal that RhoA signaling inhibits PINK1 cleavage, thereby stabilizing PINK1 protein at mitochondria. We further show that active RhoA localizes at mitochondria and interacts with PINK1, and that the mitochondrial localization of RhoA is regulated by its downstream effector protein kinase D. These findings demonstrate that RhoA activation engages a unique mechanism to regulate PINK1 accumulation, induce mitophagy and protect against ischemic stress, and implicates regulation of RhoA signaling as a potential strategy to enhance mitophagy and confer protection under stress conditions.

PurposePediatric brain tumor patients are vulnerable to radiotherapy (RT) sequelae including endocrinopathies. We compared post-RT neuroendocrine outcomes between pediatric brain tumor patients receiving photons (XRT) versus protons (PRT).MethodsUsing a prospectively maintained single-institution database, we analyzed 112 pediatric primary brain tumor patients (80 XRT, 32 PRT) from 1996 to 2019. Patient/treatment characteristics and endocrinopathy diagnoses (growth hormone deficiency [GHD], sex hormone deficiency [SHD], hypothyroidism, and requirement of hormone replacement [HRT]) were obtained via chart review. Univariable/multivariable logistic regression identified neuroendocrine outcome predictors. Time-adjusted propensity score models accounted for treatment type. Craniospinal irradiation (CSI) patients were evaluated as a sub-cohort.ResultsMedian follow-up was 6.3 and 4.4 years for XRT and PRT patients respectively. Medulloblastoma was the most common histology (38%). Half of patients (44% in XRT, 60% in PRT) received CSI. Common endocrinopathies were GHD (26% XRT, 38% PRT) and hypothyroidism (29% XRT, 19% PRT). CSI cohort PRT patients had lower odds of hypothyroidism (OR 0.16, 95% CI[0.02-0.87], p = 0.045) on multivariable regression and propensity score analyses. There were no significant differences in endocrinopathies in the overall cohort and in the odds of GHD or HRT within the CSI cohort. SHD developed in 17.1% of the XRT CSI group but did not occur in the PRT CSI group.ConclusionEndocrinopathies were common among pediatric brain tumor survivors. Among CSI patients, PRT was associated with lower risk of hypothyroidism, and potentially associated with lower incidence of SHD. Future studies should involve collaborative registries to explore the survivorship benefits of PRT.

Site-specifically modified protein bioconjugates have important applications in biology, chemistry, and medicine. Functionalizing specific protein side chains with enzymes using mild reaction conditions is of significant interest, but remains challenging. Recently, the lysine-isopeptide bond forming activity of the sortase enzyme that builds surface pili in Corynebacterium diphtheriae (CdSrtA) has been reconstituted in vitro. A mutationally activated form of CdSrtA was shown to be a promising bioconjugating enzyme that can attach Leu-Pro-Leu-Thr-Gly peptide fluorophores to a specific lysine residue within the N-terminal domain of the SpaA protein (NSpaA), enabling the labeling of target proteins that are fused to NSpaA. Here we present a detailed analysis of the CdSrtA catalyzed protein labeling reaction. We show that the first step in catalysis is rate limiting, which is the formation of the CdSrtA-peptide thioacyl intermediate that subsequently reacts with a lysine ε-amine in NSpaA. This intermediate is surprisingly stable, limiting spurious proteolysis of the peptide substrate. We report the discovery of a new enzyme variant (CdSrtAΔ) that has significantly improved transpeptidation activity, because it completely lacks an inhibitory polypeptide appendage ("lid") that normally masks the active site. We show that the presence of the lid primarily impairs formation of the thioacyl intermediate and not the recognition of the NSpaA substrate. Quantitative measurements reveal that CdSrtAΔ generates its cross-linked product with a catalytic turnover number of 1.4 ± 0.004 h-1 and that it has apparent KM values of 0.16 ± 0.04 and 1.6 ± 0.3 mM for its NSpaA and peptide substrates, respectively. CdSrtAΔ is 7-fold more active than previously studied variants, labeling >90% of NSpaA with peptide within 6 h. The results of this study further improve the utility of CdSrtA as a protein labeling tool and provide insight into the enzyme catalyzed reaction that underpins protein labeling and pilus biogenesis.

BackgroundBicycle riding's impact on erectile function remains a topic of great interest given cycling's popularity as a mode of transportation and exercise.AimWe evaluated risk factors for sexual dysfunction in male cyclists with the primary intention of determining if genital/pelvic pain and numbness are associated with erectile dysfunction (ED).MethodsWe surveyed male cyclists using an online anonymous questionnaire. Cyclists were queried on their demographics, cycling experience, and sexual function using the Sexual Health Inventory for Men (SHIM). ED was diagnosed when a completed SHIM score was

Preservation of mitochondrial integrity is critical for maintaining cellular homeostasis. Mitophagy is a mitochondria-specific type of autophagy which eliminates damaged mitochondria thereby contributing to mitochondrial quality control. Depolarization of the mitochondrial membrane potential is an established mechanism for inducing mitophagy, mediated through PINK1 stabilization and Parkin recruitment to mitochondria. Hexokinase-II (HK-II) which catalyzes the first step in glucose metabolism, also functions as a signaling molecule to regulate cell survival, and a significant fraction of cellular HK-II is associated with mitochondria (mitoHK-II). We demonstrate here that pharmacological interventions and adenoviral expression of a mitoHK-II dissociating peptide which reduce mitoHK-II levels lead to robust increases in mitochondrial Parkin and ubiquitination of mitochondrial proteins in cardiomyocytes and in a human glioblastoma cell line 1321N1, independent of mitochondrial membrane depolarization or PINK1 accumulation. MitoHK-II dissociation-induced mitophagy was demonstrated using Mito-Keima in cardiomyocytes and in 1321N1 cells. Subjecting cardiomyocytes or the in vivo heart to ischemia leads to modest dissociation of mitoHK-II. This response is potentiated by expression of the mitoHK-II dissociating peptide, which increases Parkin recruitment to mitochondria and, importantly, provides cardioprotection against ischemic stress. These results suggest that mitoHK-II dissociation is a physiologically relevant cellular event that is induced by ischemic stress, the enhancement of which protects against ischemic damage. The mechanism which underlies the effects of mitoHK-II dissociation can be attributed to the ability of Bcl2-associated athanogene 5 (BAG5), an inhibitor of Parkin, to localize to mitochondria and form a molecular complex with HK-II. Overexpression of BAG5 attenuates while knockdown of BAG5 sensitizes the effect of mitoHK-II dissociation on mitophagy. We suggest that HK-II, a glycolytic molecule, can function as a sensor for metabolic derangements at mitochondria to trigger mitophagy, and modulating the intracellular localization of HK-II could be a novel way of regulating mitophagy to prevent cell death induced by ischemic stress.

Author(s): Thomas K. Hagerman [sup.1] , Gina P. McKernan [sup.2] , Adam C. Carle [sup.3] , Justin A. Yu [sup.4] , Alyson D. Stover [sup.5] , Amy J. Houtrow [sup.6] [...], Objective To determine the prevalence of poor mental and physical health among mothers of children with special health care needs (CSHCN) and to determine the association between maternal health and the child&apos;s number of special health care needs (SHCN) and severity of ability limitation. Methods We used the combined 2016-2018 National Survey of Children&apos;s Health Dataset of 102,341 children ages 0-17 including 23,280 CSHCN. We used regression models to examine the associations of a child&apos;s number of SHCN and ability limitations with maternal health. Results Twice as many mothers of CSHCN had poor mental and physical health compared to non-CSHCN (mental 10.3% vs. 4.0%, p < .001; physical 11.9% vs 5.0%, p < .001). In regression models, increased number of SHCN and severity of activity limitations were associated with significantly increased odds of poor maternal health. Conclusions for Practice Mothers of CSHCN have worse health compared to mothers of non-CSHCN, especially those who experience social disadvantage and those with children with complex SHCN or severe ability limitations. Interventions to improve the health of these particularly vulnerable caregivers of CSHCN are warranted.

A robust and selective late-stage deuteration methodology was applied to 13C-enriched amino and alpha hydroxy acids to increase spin-lattice relaxation constant T1 for hyperpolarized 13C magnetic resonance imaging. For the five substrates with 13C-labeling on the C1-position ([1-13C]alanine, [1-13C]serine, [1-13C]lactate, [1-13C]glycine, and [1-13C]valine), significant increase of their T1 was observed at 3 T with deuterium labeling (+26%, 22%, +16%, +25% and +29%, respectively). Remarkably, in the case of [2-13C]alanine, [2-13C]serine and [2-13C]lactate, deuterium labeling led to a greater than four fold increase in T1. [1-13C,2-2H]alanine, produced using this method, was applied to in vitro enzyme assays with alanine aminotransferase, demonstrating a kinetic isotope effect.

Background: Testing etiologic heterogeneity, whether a disorder subtype is more or less impacted by a risk factor, is important for understanding causal pathways and optimizing statistical power. The study of mental health disorders especially benefits from strategic subcategorization because these disorders are heterogeneous and frequently co-occur. Existing methods to quantify etiologic heterogeneity are not appropriate for noncompeting events in an open cohort of variable-length follow-up. Thus, we developed a new method. Methods: We estimated risks from urban residence, maternal smoking during pregnancy, and parental psychiatric history, with subtypes defined by the presence or absence of a codiagnosis: autism alone, attention defi- cit hyperactivity disorder (ADHD) alone, and joint diagnoses of autism + ADHD. To calculate the risk of a single diagnosis (e.g., autism alone), we subtracted the risk for autism + ADHD from the risk for autism overall. We tested the equivalency of average risk ratios over time, using a Wald-type test and bootstrapped standard errors. Results: Urban residence was most strongly linked with autism + ADHD and least with ADHD only; maternal smoking was associated with ADHD only but not autism only; and parental psychiatric history exhibited similar associations with all subgroups. Conclusion: Our method allowed the calculation of appropriate P values to test the strength of association, informing etiologic heterogeneity wherein two of these three risk factors exhibited different impacts across diagnostic subtypes. The method used all available data, avoided neurodevelopmental outcome misclassification, exhibited robust statistical precision, and is applicable to similar heterogeneous complex conditions using common diagnostic data with variable follow-up. [ABSTRACT FROM AUTHOR]

Objective: To better understand the strategies family caregivers of children with medical complexity (CMC) utilize to deal with the stress and challenges associated with caregiving. Methods: We conducted a cross-sectional qualitative study among family caregivers of CMC receiving medical care at a children's hospital in Western Pennsylvania. Participants completed in-depth, semi-structured interviews focused on how CMC family caregivers approach and manage caregiving-related challenges and stress. Using constant comparative methodology, we inductively analyzed deidentified transcripts for emergent themes. Results: We interviewed 19 participants (89.4% female) with a mean age of 43 years (range 32–54 years). The mean age of the participants' children was 10.8 years (range 1–20 years). Twelve participants' children identified as white and four identified as Black. Three central themes regarding CMC caregivers' stress-coping strategies emerged: (1) maintaining a positive mindset, (2) developing and relying on interpersonal support networks, and (3) making time for self-preservation. All three themes were universally reported (n = 19/19) by our participants. The most common subthemes for each theme, respectively, focused on staying hopeful and celebrating moments of joy; cultivating supportive relationships with family, friends, and fellow CMC family caregivers; and finding pleasure in "little things" (e.g., everyday activities and hobbies). Conclusion: Family caregivers of CMC utilize a multi-faceted approach to cope with the stress and challenges routinely encountered in caring for CMC. This study's findings could be used to inform future clinical efforts and research directions aiming to improve clinicians' ability to support CMC caregivers' well-being. [ABSTRACT FROM AUTHOR]