The PD-1-PD-L1 pathway maintains an immunosuppressive environment essential for neonatal heart regeneration.

The adult mouse heart responds to injury by scarring with consequent loss of contractile function, whereas the neonatal heart possesses the ability to regenerate. Activation of the immune system is among the first events upon tissue injury. It has been shown that immune response kinetics differ between regeneration and pathological remodeling, yet the underlying mechanisms of the distinct immune reactions during tissue healing remain unclear. Here we show that the immunomodulatory PD-1-PD-L1 pathway is highly active in regenerative neonatal hearts but rapidly silenced later in life. Deletion of the PD-1 receptor or inactivation of its ligand PD-L1 prevented regeneration of neonatal hearts after injury. Disruption of the pathway during neonatal cardiac injury led to increased inflammation and aberrant T cell activation, which ultimately impaired cardiac regeneration. Our findings reveal an immunomodulatory and cardioprotective role for the PD-1-PD-L1 pathway in heart regeneration and offer potential avenues for the control of adult tissue regeneration.

Network analysis of large-scale ImmGen and Tabula Muris datasets highlights metabolic diversity of tissue mononuclear phagocytes.

The diversity of mononuclear phagocyte (MNP) subpopulations across tissues is one of the key physiological characteristics of the immune system. Here, we focus on understanding the metabolic variability of MNPs through metabolic network analysis applied to three large-scale transcriptional datasets: we introduce (1) an ImmGen MNP open-source dataset of 337 samples across 26 tissues; (2) a myeloid subset of ImmGen Phase I dataset (202 MNP samples); and (3) a myeloid mouse single-cell RNA sequencing (scRNA-seq) dataset (51,364 cells) assembled based on Tabula Muris Senis. To analyze such large-scale datasets, we develop a network-based computational approach, genes and metabolites (GAM) clustering, for unbiased identification of the key metabolic subnetworks based on transcriptional profiles. We define 9 metabolic subnetworks that encapsulate the metabolic differences within MNP from 38 different tissues. Obtained modules reveal that cholesterol synthesis appears particularly active within the migratory dendritic cells, while glutathione synthesis is essential for cysteinyl leukotriene production by peritoneal and lung macrophages.

Long-term culture-expanded alveolar macrophages restore their full epigenetic identity after transfer in vivo.

Alveolar macrophages (AMs) are lung tissue-resident macrophages that can be expanded in culture, but it is unknown to what extent culture affects their in vivo identity. Here we show that mouse long-term ex vivo expanded AMs (exAMs) maintained a core AM gene expression program, but showed culture adaptations related to adhesion, metabolism and proliferation. Upon transplantation into the lung, exAMs reacquired full transcriptional and epigenetic AM identity, even after several months in culture and could self-maintain long-term in the alveolar niche. Changes in open chromatin regions observed in culture were fully reversible in transplanted exAMs and resulted in a gene expression profile indistinguishable from resident AMs. Our results indicate that long-term proliferation of AMs in culture did not compromise cellular identity in vivo. The robustness of exAM identity provides new opportunities for mechanistic analysis and highlights the therapeutic potential of exAMs.

Enhancing Polyvalent Cation Rejection Using Perfluorophenylazide-Grafted-Copolymer Membrane Coatings.

Surface modification offers a straightforward means to alter and enhance the properties and performance of materials, such as nanofiltration membranes for water softening. Herein, we demonstrate how a membrane's surface charge can be altered by grafting different electrostatically varying copolymers onto commercial membrane surfaces using perfluorophenylazide (PFPA) photochemistry for enhanced ion separation performance. The native membrane's performance-i.e., in terms of divalent cation separation-with copolymer coatings containing a positively charged quaternary ammonium (-N(Me)3+), a negatively charged sulfonate (-SO3-), and an essentially neutral zwitterion (sulfobetaine, -N(Me)2R2+, and -SO3-), respectively, indicates that: (a) the sulfonated polymer induces robust Coulombic exclusion of divalent anions as compared to the negatively charged native membrane surface on account of its higher negative charge; (b) the positively charged ammonium coating induces exclusion of cations more effectively than the native membrane; and significantly, (c) the zwitterion polymer coating, which reduces the surface roughness and improves wettability, in spite of its near-neutral charge enhances exclusion of both divalent cations and anions on account of aperture sieving by the compact zwitterion polymer that arises from its ability to limit the size of ions that transport through the polymer along with dielectric exclusion. The outcomes thereby inform new pathways to achieve size- and charge-based exclusion of ionic, molecular, and other species contained in liquid streams.

Efecto de una intervención motriz basada en el método de descubrimiento guiado sobre los patrones básicos de movimiento de un niño de 9 años: estudio de caso / Effect of A Motor Intervention Based on The Guided Discovery Method on The Basic Movement Patterns of A 9-Year- Child: Case Study / Efeito de uma intervenção motora baseada no método da descoberta guiada sobre os padrões básicos de movimento de uma criança de 9 anos: estudo de caso

Resumen: El propósito de esta investigación fue determinar el efecto de una intervención motriz basada en el método de descubrimiento guiado sobre los patrones básicos de movimiento de un niño típico. Se contó con la participación de un infante de 9 años que se percibe físicamente activo, practica deportes con regularidad, asiste a la escuela y posee un estado de salud y cognitivo normal. La intervención se aplicó durante 6 semanas, 2 sesiones de evaluación pretest y postest, por medio del instrumento para la evaluación de los patrones básicos de movimiento, y 4 sesiones prácticas de 60 minutos, un día a la semana, durante 4 semanas. Para el análisis de resultados, se utilizó el porcentaje de cambio. Los resultados, luego de la intervención, mostraron mejorías en el porcentaje de cambio, en 4 de los de los patrones locomotores entre el 33.33 % y 300 %; en los patrones manipulativos, entre el 37.5 % y 900 %; así como un mejoramiento del 50 %, en el total de las destrezas locomotoras, y de 85,18%, la totalidad de las destrezas manipulativas. A su vez, tuvo una mejoría global en PBM del 65.08 %. Se concluye que, luego de este estudio de caso, un modelo de intervención motriz basado en el método empleado puede ser una herramienta útil para mejorar las destrezas motoras básicas en la población infantil.

Abstract: The purpose of this research was to determine the effect of a motor intervention based on the guided discovery method on the basic movement patterns of a typical child. The study involved a 9-year-old child who is physically active, plays sports regularly, attends school, and has normal cognitive and health status. The intervention was applied during six weeks, two pre-test and post-test evaluation sessions through the Instrument for the Evaluation of Basic Movement Patterns, and four practical sessions of 60 minutes, one day a week, for four weeks. For the analysis of results, the percentage change was used. The results after the intervention showed improvements in the percentage of change in four of the locomotive patterns between 33.33% and 300%; in the manipulative patterns between 37.5% and 900%; as well as an improvement of 50% in the total of locomotive skills and 85.18% in the total of manipulative skills. In turn, it had an overall improvement in PBM of 65.08%. It is concluded that after this case study, a model of motor intervention based on the method used can be a useful tool to improve basic motor skills in children.

Resumo: O objetivo desta pesquisa foi determinar o efeito de uma intervenção motora baseada no método de descoberta guiada sobre os padrões básicos de movimento de uma criança típica. O estudo envolveu uma criança de 9 anos de idade que é fisicamente ativa, pratica esportes regularmente, frequenta a escola e tem estado cognitivo e de saúde normal. A intervenção foi aplicada durante seis semanas, duas sessões de avaliação pré-teste e pós-teste através do Instrumento de Avaliação de Padrões Básicos de Movimento e quatro sessões práticas de 60 minutos, um dia por semana, durante quatro semanas. Para a análise dos resultados, foi utilizada a mudança percentual. Os resultados após a intervenção mostraram melhora no percentual de mudança em quatro dos padrões locomotivos entre 33,33% e 300%; nos padrões manipulativos entre 37,5% e 900%; bem como melhora de 50% no total de habilidades locomotivas e 85,18% no total de habilidades manipulativas. Por sua vez, teve uma melhora global na PBM de 65,08%. Conclui-se que, após este estudo de caso, um modelo de intervenção motora baseado no método utilizado pode ser uma ferramenta útil para melhorar as habilidades motoras básicas em crianças.

Direct grafting of tetraaniline via perfluorophenylazide photochemistry to create antifouling, low bio-adhesion surfaces.

Conjugated polyaniline has shown anticorrosive, hydrophilic, antibacterial, pH-responsive, and pseudocapacitive properties making it of interest in many fields. However, in situ grafting of polyaniline without harsh chemical treatments is challenging. In this study, we report a simple, fast, and non-destructive surface modification method for grafting tetraaniline (TANI), the smallest conjugated repeat unit of polyaniline, onto several materials via perfluorophenylazide photochemistry. The new materials are characterized by nuclear magnetic resonance (NMR) and electrospray ionization (ESI) mass spectroscopy. TANI is shown to be covalently bonded to important carbon materials including graphite, carbon nanotubes (CNTs), and reduced graphene oxide (rGO), as confirmed by transmission electron microscopy (TEM). Furthermore, large area modifications on polyethylene terephthalate (PET) films through dip-coating or spray-coating demonstrate the potential applicability in biomedical applications where high transparency, patternability, and low bio-adhesion are needed. Another important application is preventing biofouling in membranes for water purification. Here we report the first oligoaniline grafted water filtration membranes by modifying commercially available polyethersulfone (PES) ultrafiltration (UF) membranes. The modified membranes are hydrophilic as demonstrated by captive bubble experiments and exhibit extraordinarily low bovine serum albumin (BSA) and Escherichia coli adhesions. Superior membrane performance in terms of flux, BSA rejection and flux recovery after biofouling are demonstrated using a cross-flow system and dead-end cells, showing excellent fouling resistance produced by the in situ modification.

SIRT1 regulates macrophage self-renewal.

Mature differentiated macrophages can self-maintain by local proliferation in tissues and can be extensively expanded in culture under specific conditions, but the mechanisms of this phenomenon remain only partially defined. Here, we show that SIRT1, an evolutionary conserved regulator of life span, positively affects macrophage self-renewal ability in vitro and in vivo Overexpression of SIRT1 during bone marrow-derived macrophage differentiation increased their proliferative capacity. Conversely, decrease of SIRT1 expression by shRNA inactivation, CRISPR/Cas9 mediated deletion and pharmacological inhibition restricted macrophage self-renewal in culture. Furthermore, pharmacological SIRT1 inhibition in vivo reduced steady state and cytokine-induced proliferation of alveolar and peritoneal macrophages. Mechanistically, SIRT1 inhibition negatively regulated G1/S transition, cell cycle progression and a network of self-renewal genes. This included inhibition of E2F1 and Myc and concomitant activation of FoxO1, SIRT1 targets mediating cell cycle progression and stress response, respectively. Our findings indicate that SIRT1 is a key regulator of macrophage self-renewal that integrates cell cycle and longevity pathways. This suggests that macrophage self-renewal might be a relevant parameter of ageing.

Microglia development follows a stepwise program to regulate brain homeostasis.

Microglia, the resident myeloid cells of the central nervous system, play important roles in life-long brain maintenance and in pathology. Despite their importance, their regulatory dynamics during brain development have not been fully elucidated. Using genome-wide chromatin and expression profiling coupled with single-cell transcriptomic analysis throughout development, we found that microglia undergo three temporal stages of development in synchrony with the brain--early, pre-, and adult microglia--which are under distinct regulatory circuits. Knockout of the gene encoding the adult microglia transcription factor MAFB and environmental perturbations, such as those affecting the microbiome or prenatal immune activation, led to disruption of developmental genes and immune response pathways. Together, our work identifies a stepwise microglia developmental program integrating immune response pathways that may be associated with several neurodevelopmental disorders.

Prevalence of Diabetic Retinopathy in a Clinic Population from Puerto Rico.

PURPOSE: Diabetic retinopathy (DR) is a preventable or treatable cause of blindness in the adult population. The prevalence of diabetes mellitus (DM) in Puerto Ricans is the highest among Hispanics. This study evaluated the prevalence of DR in a screening program of DM subjects in a clinic system in Puerto Rico. METHODS: A retrospective cross-sectional health records study of DM patients referred by primary care physicians for dilated retinal evaluation to the Inter American University of Puerto Rico School of Optometry Juana Diaz Eye Institute Clinic between 2001 and 2009 was performed. All subjects underwent a complete eye evaluation including fundus photography. Photographs were graded following the Early Treatment Diabetic Retinopathy Study protocols. RESULTS: A total of 411 randomly selected health records of DM subjects older than 30 years were included. The estimated prevalence of DR among all subjects is 37.7%. DR was more common in males (47.2%) than females (33.7%). The age range with higher frequency of DR is among ages 60 to 69 (34.8%) and the lowest between ages 30 and 39 (3.9%). The average number of years since initial DM diagnosis was 12.48. Probability of developing DR increases with longer duration of DM (p < 0.05). The most common stage was mild non-proliferative DR (22.6%). CONCLUSIONS: Our data revealed that prevalence of DR was high among Puerto Ricans. Mild stage retinopathy was most prevalent and there exists an increase in probability to develop DR with duration of DM. The prevalence of DR in total population may be different than the findings presented in this paper. Comprehensive studies are needed to understand and estimate the progression and impact of DR in this population.

Structural and functional analysis of two di-domain aromatase/cyclases from type II polyketide synthases.

Aromatic polyketides make up a large class of natural products with diverse bioactivity. During biosynthesis, linear poly-ß-ketone intermediates are regiospecifically cyclized, yielding molecules with defined cyclization patterns that are crucial for polyketide bioactivity. The aromatase/cyclases (ARO/CYCs) are responsible for regiospecific cyclization of bacterial polyketides. The two most common cyclization patterns are C7-C12 and C9-C14 cyclizations. We have previously characterized three monodomain ARO/CYCs: ZhuI, TcmN, and WhiE. The last remaining uncharacterized class of ARO/CYCs is the di-domain ARO/CYCs, which catalyze C7-C12 cyclization and/or aromatization. Di-domain ARO/CYCs can further be separated into two subclasses: "nonreducing" ARO/CYCs, which act on nonreduced poly-ß-ketones, and "reducing" ARO/CYCs, which act on cyclized C9 reduced poly-ß-ketones. For years, the functional role of each domain in cyclization and aromatization for di-domain ARO/CYCs has remained a mystery. Here we present what is to our knowledge the first structural and functional analysis, along with an in-depth comparison, of the nonreducing (StfQ) and reducing (BexL) di-domain ARO/CYCs. This work completes the structural and functional characterization of mono- and di-domain ARO/CYCs in bacterial type II polyketide synthases and lays the groundwork for engineered biosynthesis of new bioactive polyketides.

Recruiting and retaining low-income, multi-ethnic women into randomized controlled trials: successful strategies and staffing.

Developing effective recruitment and retention strategies in populations with traditionally high attrition rates is critical to the success of Randomized Controlled Trials (RCTs). Data on successful participation of women from low-income, minority populations in RCTs of behavioral interventions are limited. This is problematic given the multiplicity of Healthy People 2020 goals that target health disparities in these populations. This paper reports successful recruitment and retention methods from two separately funded NIH clinical trials of primary care-based prenatal interventions to increase breastfeeding among ethnically diverse, low-income women in urban medical centers in the Bronx, NY. It also presents the required staff effort necessary to conduct such a successful RCT, in terms of full-time equivalents (FTEs). Results include timely recruitment of 941 participants over 29 months, with 98.1% completing >¯¯1 follow-up interview. A recruitment and retention plan that maximized study staff access and availability to the participant, as well as strong study staff rapport with participants, addressed previously reported barriers in this population, optimizing follow-up rates. A qualitative assessment of the participants' study experience suggesting that high retention was due to strong rapport with participants, short interviews requiring little time commitment, and participants' perception of the study as informative, provides further evidence of our approach's effectiveness. Logistical protocol procedures and staff management strategies relating to successful recruitment/retention are provided to propose a practical, cost-effective and translational recruitment-retention plan for other researchers to adopt.

Impaired turnover of autophagolysosomes in cathepsin L deficiency.

Some of the phenotypes of mice deficient for the lysosomal cysteine endopeptidase cathepsin L (Ctsl) are characterized by large dysmorphic vesicles in the cytoplasm. Specifically, the heart (dilative cardiomyopathy), the thyroid (impaired thyroglobulin processing) and keratinocytes (periodic hair loss and epidermal hyperproliferation) are affected. We hypothesized that the formation of aberrant vesicles is owing to defects in macroautophagy. Therefore, primary mouse embryonic fibroblasts (MEF), which were derived from Ctsl(-/-) animals crossed with mice transgenic for the autophagy marker GFP-LC3, were investigated. Ctsl(-/-) MEF show increased number and size of vesicular structures belonging to the 'acidic' cellular compartment and are also characterized by GFP-LC3. Induction of autophagy by nutrient starvation or rapamycin treatment showed no significant impairment of the initiation of autophagy, the formation of autophagosomes or autophagosome-lysosome fusion in Ctsl(-/-) MEF, but co-localization of GFP-LC3 and Lamp1 revealed unusually large autophagolysosomes filled with Lamp1. Furthermore, the soluble lysosomal enzyme cathepsin D was elevated in Ctsl(-/-) MEF. Thus, degradation of autophagolysosomal content is impaired in the absence of Ctsl. This could slow the turnover of autophagolysosomes and result in accumulation of the dysmorphic and 'acidic' vesicles that were previously described in the context of the pathological phenotypes of Ctsl(-/-) mice.