Deletion of CEP164 in mouse photoreceptors post-ciliogenesis interrupts ciliary intraflagellar transport (IFT).

Centrosomal protein of 164 kDa (CEP164) is located at distal appendages of primary cilia and is necessary for basal body (BB) docking to the apical membrane. To investigate the function of photoreceptor CEP164 before and after BB docking, we deleted CEP164 during retina embryonic development (Six3Cre), in postnatal rod photoreceptors (iCre75) and in mature retina using tamoxifen induction (Prom1-ETCre). BBs dock to the cell cortex during postnatal day 6 (P6) to extend a connecting cilium (CC) and an axoneme. P6 retina-specific knockouts (retCep164-/-) are unable to dock BBs, thereby preventing formation of CC or outer segments (OSs). In rod-specific knockouts (rodCep164-/-), Cre expression starts after P7 and CC/OS form. P16 rodCep164-/- rods have nearly normal OS lengths, and maintain OS attachment through P21 despite loss of CEP164. Intraflagellar transport components (IFT88, IFT57 and IFT140) were reduced at P16 rodCep164-/- BBs and CC tips and nearly absent at P21, indicating impaired intraflagellar transport. Nascent OS discs, labeled with a fluorescent dye on P14 and P18 and harvested on P19, showed continued rodCep164-/- disc morphogenesis but absence of P14 discs mid-distally, indicating OS instability. Tamoxifen induction with PROM1ETCre;Cep164F/F (tamCep164-/-) adult mice affected maintenance of both rod and cone OSs. The results suggest that CEP164 is key towards recruitment and stabilization of IFT-B particles at the BB/CC. IFT impairment may be the main driver of ciliary malfunction observed with hypomorphic CEP164 mutations.

The glutamate/aspartate transporter EAAT1 is crucial for T-cell acute lymphoblastic leukemia proliferation and survival.

T-cell acute lymphoblastic leukemia (T-ALL) is a cancer of the immune system. Approximately 20% of paediatric and 50% of adult T-ALL patients have refractory disease or relapse and die from the disease. To improve patient outcome new therapeutics are needed. With the aim to identify new therapeutic targets, we combined the analysis of T-ALL gene expression and metabolism to identify the metabolic adaptations that T-ALL cells exhibit. We found that glutamine uptake is essential for T-ALL proliferation. Isotope tracing experiments showed that glutamine fuels aspartate synthesis through the TCA cycle and that glutamine and glutamine-derived aspartate together supply three nitrogen atoms in purines and all but one atom in pyrimidine rings. We show that the glutamate-aspartate transporter EAAT1 (SLC1A3), which is normally expressed in the central nervous system, is crucial for glutamine conversion to aspartate and nucleotides and that T-ALL cell proliferation depends on EAAT1 function. Through this work, we identify EAAT1 as a novel therapeutic target for T-ALL treatment.

Formyl peptide receptor 2 regulates monocyte recruitment to promote intestinal mucosal wound repair.

Mucosal wound repair is coordinated by dynamic crosstalk between endogenous and exogenous mediators and specific receptors on epithelial cells and infiltrating immune cells. One class of such receptor-ligand pairs involves formyl peptide receptors (FPRs) that have been shown to influence inflammatory response and repair. Here we explored the role of murine Fpr2/3, an ortholog of human FPR2/receptor for lipoxin A4 (ALX), in orchestrating intestinal mucosal repair. Compared with wild-type (WT) mice, Fpr2/3-/- mice exhibited delayed recovery from acute experimental colitis and perturbed repair after biopsy-induced colonic mucosal injury. Decreased numbers of infiltrating monocytes were observed in healing wounds from Fpr2/3-/- mice compared with WT animals. Bone marrow transplant experiments revealed that Fpr2/3-/- monocytes showed a competitive disadvantage when infiltrating colonic wounds. Moreover, Fpr2/3-/- monocytes were defective in chemotactic responses to the chemokine CC chemokine ligand (CCL)20, which is up-regulated during early phases of inflammation. Analysis of Fpr2/3-/- monocytes revealed altered expression of the CCL20 receptor CC chemokine receptor (CCR)6, suggesting that Fpr2/3 regulates CCL20-CCR6-mediated monocyte chemotaxis to sites of mucosal injury in the gut. These findings demonstrate an important contribution of Fpr2/3 in facilitating monocyte recruitment to sites of mucosal injury to influence wound repair.-Birkl, D., O'Leary, M. N., Quiros, M., Azcutia, V., Schaller, M., Reed, M., Nishio, H., Keeney, J., Neish, A. S., Lukacs, N. W., Parkos, C. A., Nusrat, A. Formyl peptide receptor 2 regulates monocyte recruitment to promote intestinal mucosal wound repair.

Quantitative Isotopomer Rates in Real-Time Metabolism of Cells Determined by NMR Methods.

Tracer-based metabolism is becoming increasingly important for studying metabolic mechanisms in cells. NMR spectroscopy offers several approaches to measure label incorporation in metabolites, including 13 C- and 1 H-detected spectra. The latter are generally more sensitive, but quantification depends on the proton-carbon 1 JCH coupling constant, which varies significantly between different metabolites. It is therefore not possible to have one experiment optimised for all metabolites, and quantification of 1 H-edited spectra such as HSQCs requires precise knowledge of coupling constants. Increasing interest in tracer-based and metabolic flux analysis requires robust analyses with reasonably small acquisition times. Herein, we compare 13 C-filtered and 13 C-edited methods for quantification and show the applicability of the methods for real-time NMR spectroscopy of cancer-cell metabolism, in which label incorporations are subject to constant flux. We find an approach using a double filter to be most suitable and sufficiently robust to reliably obtain 13 C incorporations from difference spectra. This is demonstrated for JJN3 multiple myeloma cells processing glucose over 24 h. The proposed method is equally well suited for calculating the level of label incorporation in labelled cell extracts in the context of metabolic flux analysis.

Metabonomics uncovers a reversible proatherogenic lipid profile during infliximab therapy of inflammatory bowel disease.

BACKGROUND: One-third of inflammatory bowel disease (IBD) patients show no response to infliximab (IFX) induction therapy, and approximately half of patients responding become unresponsive over time. Thus, identification of potential treatment response biomarkers are of great clinical significance. This study employs spectroscopy-based metabolic profiling of serum from patients with IBD treated with IFX and healthy subjects (1) to substantiate the use of spectroscopy as a semi-invasive diagnostic tool, (2) to identify potential biomarkers of treatment response and (3) to characterise the metabolic changes during management of patients with tumour necrosis factor-α inhibitors. METHODS: Successive serum samples collected during IFX induction treatment (weeks 0, 2, 6 and 14) from 87 IBD patients and 37 controls were analysed by 1H nuclear magnetic resonance (NMR) spectroscopy. Data were analysed with principal components analysis and orthogonal projection to latent structures discriminant analysis using SIMCA-P+ v12 and MATLAB. RESULTS: Metabolic profiles were significantly different between active ulcerative colitis and controls, active Crohn's disease and controls, and quiescent Crohn's disease and controls. Metabolites holding differential power belonged primarily to lipids and phospholipids with proatherogenic characteristics and metabolites in the pyruvate metabolism, suggestive of an intense inflammation-driven energy demand. IBD patients not responding to IFX were identified as a potentially distinct group based on their metabolic profile, although no applicable response biomarkers could be singled out in the current setting. CONCLUSION: 1H NMR spectroscopy of serum samples is a powerful semi-invasive diagnostic tool in flaring IBD. With its use, we provide unique insights into the metabolic changes taking place during induction treatment with IFX. Of distinct clinical relevance is the identification of a reversible proatherogenic lipid profile in IBD patients with active disease, which partially explains the increased risk of cardiovascular disease associated with IBD.

Sirtuin 1 Regulates Dendritic Cell Activation and Autophagy during Respiratory Syncytial Virus-Induced Immune Responses.

Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract infection in children worldwide. Sirtuin 1 (SIRT1), an NAD(+)-dependent deacetylase, has been associated with the induction of autophagy and the regulation of inflammatory mediators. We found that Sirt1 was upregulated in mouse lung after RSV infection. Infected animals that received EX-527, a selective SIRT1 inhibitor, displayed exacerbated lung pathology, with increased mucus production, elevated viral load, and enhanced Th2 cytokine production. Gene expression analysis of isolated cell populations revealed that Sirt1 was most highly upregulated in RSV-treated dendritic cells (DCs). Upon RSV infection, EX-527-treated DCs, Sirt1 small interfering RNA-treated DCs, or DCs from conditional knockout (Sirt1(f/f)-CD11c-Cre(+)) mice showed downregulated inflammatory cytokine gene expression and attenuated autophagy. Finally, RSV infection of Sirt1(f/f)-CD11c-Cre(+) mice resulted in altered lung and lymph node cytokine responses, leading to exacerbated pathology. These data indicate that SIRT1 promotes DC activation associated with autophagy-mediated processes during RSV infection, thereby directing efficient antiviral immune responses.

IL-27R-mediated regulation of IL-17 controls the development of respiratory syncytial virus-associated pathogenesis.

IL-27 is a heterodimeric cytokine composed of the subunits p28 and Epstein-Barr virus induced gene (EBI)-3 and is known for its effects on T-cell function and differentiation. IL-27 signals through the widely expressed IL-27 receptor (IL-27R), composed of the ligand-specific IL-27Rα chain and gp130. Engagement of the IL-27R activates STAT1 signaling, induces the expression of the type 1 helper T-cell (Th1) cytokine, interferon γ, and suppresses the differentiation of Th2 and Th17 cells. This study investigates the role of IL-27 signaling in respiratory syncytial virus (RSV) infection using IL-27Rα-deficient mice (IL-27rKO). Analysis of lungs from RSV-infected IL-27rKO mice showed exacerbation of mucus secretion compared with wild type, as well as enhanced expression of Muc5ac and Gob5 mRNA, markers of goblet cell metaplasia/hyperplasia. When compared with wild-type mice, RSV-challenged IL-27rKO mice had enhanced expression of Th17-associated cytokine IL-17a and an imbalance between Th1 and Th2 cytokine levels. Neutralization of IL-17 in RSV-infected IL-27rKO mice resulted in a significant decrease in the pulmonary mucus response and inhibition of the Th2-associated cytokines. Interestingly, IL-17 blockage led to an increase in the expression of IL-27 subunits p28 and EBI-3 in the lungs and lymph nodes of RSV-infected mice. Thus, IL-27 functions as a regulatory cytokine during RSV pathogenesis by suppressing the development of Th17 cells, but it also appears to be regulated by IL-17 induced by the virus.

Autophagy-inducing protein beclin-1 in dendritic cells regulates CD4 T cell responses and disease severity during respiratory syncytial virus infection.

Recent work demonstrated the importance of macroautophagy in dendritic cell (DC) maturation and innate cytokine production upon viral infection through delivery of cytoplasmic viral components to intracellular TLRs. To study the functional consequences of impaired autophagosome formation during a respiratory syncytial virus (RSV) infection, mice harboring significant autophagy defects due to Beclin-1 haploinsufficiency (Beclin-1(+/-)) were used. Upon RSV infection in vivo, lungs of Beclin-1(+/-) mice showed increased Th2 cytokine production, mucus secretion, and lung infiltration of eosinophils and inflammatory DCs. Although isolated airway epithelial cells from Beclin-1(+/-) mice demonstrated little change compared with wild-type mice, Beclin-1(+/-) pulmonary and bone marrow-derived DCs showed decreased expression of MHC class II and innate cytokine production upon RSV infection. Further examination indicated that Beclin-1(+/-) DCs stimulated less IFN-γ and IL-17 production by cocultured CD4(+) T cells and increased Th2 cytokine production in comparison with wild-type controls. Finally, adoptive transfer of RSV-infected Beclin-1(+/-) DCs into the airways of wild-type mice produced severe lung pathology and increased Th2 cytokine production upon subsequent RSV challenge compared with wild-type DC transfer controls. These results indicate a critical role for autophagy in DCs during pulmonary viral infection, facilitating appropriate antiviral adaptive immune responses.

Autophagy-mediated dendritic cell activation is essential for innate cytokine production and APC function with respiratory syncytial virus responses.

The regulation of innate immune responses during viral infection is a crucial step to promote antiviral reactions. Recent studies have drawn attention to a strong relationship of pathogen-associated molecular pattern recognition with autophagy for activation of APC function. Our initial observations indicated that autophagosomes formed in response to respiratory syncytial virus (RSV) infection of dendritic cells (DC). To further investigate whether RSV-induced DC activation and innate cytokine production were associated with autophagy, we used several methods to block autophagosome formation. Using 3-MA, small interfering RNA inhibition of LC3, or Beclin(+/-) mouse-derived DC, studies established a relationship between RSV-induced autophagy and enhanced type I IFN, TNF, IL-6, and IL-12p40 expression. Moreover, autophagosome formation induced by starvation also promoted innate cytokine expression in DC. The induction of starvation-induced autophagy in combination with RSV infection synergistically enhanced DC cytokine expression that was blocked by an autophagy inhibitor. The latter synergistic responses were differentially altered in DC from MyD88(-/-) and TRIF(-/-) mice, supporting the concept of autophagy-mediated TLR signaling. In addition, blockade of autophagy in RSV-infected DC inhibited the maturation of DC as assessed by MHC class II and costimulatory molecule expression. Subsequently, we demonstrated that inhibition of autophagy in DC used to stimulate primary OVA-induced and secondary RSV-infected responses significantly attenuated cytokine production by CD4(+) T cells. Thus, these studies have outlined that autophagy in DC after RSV infection is a crucial mechanism for driving innate cytokine production, leading to altered acquired immune responses.

Arf-like Protein 2 (ARL2) Controls Microtubule Neogenesis during Early Postnatal Photoreceptor Development.

Arf-like protein 2 (ARL2) is a ubiquitously expressed small GTPase with multiple functions. In a cell culture, ARL2 participates with tubulin cofactor D (TBCD) in the neogenesis of tubulin αß-heterodimers, the building blocks of microtubules. To evaluate this function in the retina, we conditionally deleted ARL2 in mouse retina at two distinct stages, either during the embryonic development (retArl2-/-) or after ciliogenesis specifically in rods (rodArl2-/-). retArl2-/- retina sections displayed distorted nuclear layers and a disrupted microtubule cytoskeleton (MTC) as early as postnatal day 6 (P6). Rod and cone outer segments (OS) did not form. By contrast, the rod ARL2 knockouts were stable at postnatal day 35 and revealed normal ERG responses. Cytoplasmic dynein is reduced in retArl2-/- inner segments (IS), suggesting that dynein may be unstable in the absence of a normal MTC. We investigated the microtubular stability in the absence of either ARL2 (retARL2-/-) or DYNC1H1 (retDync1h1-/-), the dynein heavy chain, and found that both the retArl2-/- and retDync1h1-/- retinas exhibited reduced microtubules and nuclear layer distortion. The results suggest that ARL2 and dynein depend on each other to generate a functional MTC during the early photoreceptor development.

Crosstalk between AML and stromal cells triggers acetate secretion through the metabolic rewiring of stromal cells.

Acute myeloid leukaemia (AML) cells interact and modulate components of their surrounding microenvironment into their own benefit. Stromal cells have been shown to support AML survival and progression through various mechanisms. Nonetheless, whether AML cells could establish beneficial metabolic interactions with stromal cells is underexplored. By using a combination of human AML cell lines and AML patient samples together with mouse stromal cells and a MLL-AF9 mouse model, here we identify a novel metabolic crosstalk between AML and stromal cells where AML cells prompt stromal cells to secrete acetate for their own consumption to feed the tricarboxylic acid cycle (TCA) and lipid biosynthesis. By performing transcriptome analysis and tracer-based metabolic NMR analysis, we observe that stromal cells present a higher rate of glycolysis when co-cultured with AML cells. We also find that acetate in stromal cells is derived from pyruvate via chemical conversion under the influence of reactive oxygen species (ROS) following ROS transfer from AML to stromal cells via gap junctions. Overall, we present a unique metabolic communication between AML and stromal cells and propose two different molecular targets, ACSS2 and gap junctions, that could potentially be exploited for adjuvant therapy.

A lyophilized red grape pomace containing proanthocyanidin-rich dietary fiber induces genetic and metabolic alterations in colon mucosa of female C57BL/6J mice.

Diet plays a decisive role in promoting or preventing colon cancer. However, the specific effects of some nutrients remain unclear. The capacity of fruit and vegetables to prevent cancer has been associated with their fiber and antioxidant composition. We investigated whether consumption of a lyophilized red grape pomace containing proanthocyanidin-rich dietary fiber (grape antioxidant dietary fiber, GADF) by female C57BL/6J mice would affect the serum metabolic profile or colon mucosa gene expression using NMR techniques and DNA microarray, respectively. The mice were randomly assigned to 2 groups that for 2 wk consumed a standard rodent diet and were gavaged with 100 mg/kg body weight GADF suspended in water or an equivalent volume of plain tap water (10 mL/kg body weight). The amount of fiber supplemented was calculated to equal the current recommended daily levels of fiber consumption for humans. The inclusion of dietary GADF induced alterations in the expression of tumor suppressor genes and proto-oncogenes as well as the modulation of genes from pathways, including lipid biosynthesis, energy metabolism, cell cycle, and apoptosis. Overexpression of enzymes pertaining to the xenobiotic detoxifying system and endogenous antioxidant cell defenses was also observed. In summary, the genetic and metabolic profiles induced by GADF were consistent with the preventive effects of fiber and polyphenols. On the basis of these observations, we propose that GADF may contribute to reducing the risk of colon cancer.

Conditional Deletion of Cytoplasmic Dynein Heavy Chain in Postnatal Photoreceptors.

Purpose: Cytoplasmic dynein-1 (henceforth dynein) moves cargo in conjunction with dynactin toward the minus end of microtubules. The dynein heavy chain, DYNC1H1, comprises the backbone of dynein, a retrograde motor. Deletion of Dync1h1 abrogates dynein function. The purpose of this communication is to demonstrate effects of photoreceptor dynein inactivation during late postnatal development and in adult retina. Methods: We mated Dync1h1F/F mice with iCre75 and Prom1-CreERT2 mice to generate conditional rod and tamoxifen-induced knockout in rods and cones, respectively. We documented retina degeneration with confocal microscopy at postnatal day (P) 10 to P30 for the iCre75 line and 1 to 4 weeks post tamoxifen induction (wPTI) for the Prom1-CreERT2 line. We performed scotopic and photopic electroretinography (ERG) at P16 to P30 in the iCre75 line and at 1-week increments in the Prom1-CreERT2 line. Results were evaluated statistically using Student's t-test, two-factor ANOVA, and Welch's ANOVA. Results: Cre-induced homologous recombination of Dync1h1F/F mice truncated DYNC1H1 after exon 23. rodDync1h1-/- photoreceptors degenerated after P14, reducing outer nuclear layer (ONL) thickness and combined inner segment/outer segment (IS/OS) length significantly by P18. Scotopic ERG a-wave amplitudes decreased by P16 and were extinguished at P30. Cones were stable under rod-knockout conditions until P21 but inactive at P30. In tamDync1h1-/- photoreceptors, the IS/OS began shortening by 3wPTI and were nearly eliminated by 4wPTI. The ONL shrank significantly over this interval, indicating rapid photoreceptor degeneration following the loss of dynein. Conclusions: Our results demonstrate dynein is essential for the secretory pathway, formation of outer segments, and photoreceptor maintenance.

Effect of conditional deletion of cytoplasmic dynein heavy chain DYNC1H1 on postnatal photoreceptors.

Cytoplasmic dynein (dynein 1), a major retrograde motor of eukaryotic cells, is a 1.4 MDa protein complex consisting of a pair of heavy chains (DYNC1H1) and a set of heterodimeric noncatalytic accessory components termed intermediate, light intermediate and light chains. DYNC1H1 (4644 amino acids) is the dynein backbone encoded by a gene consisting of 77 exons. We generated a floxed Dync1h1 allele that excises exons 24 and 25 and truncates DYNC1H1 during Six3Cre-induced homologous recombination. Truncation results in loss of the motor and microtubule-binding domain. Dync1h1F/F;Six3Cre photoreceptors degenerated rapidly within two postnatal weeks. In the postnatal day 6 (P6) Dync1h1F/F;Six3Cre central retina, outer and inner nuclear layers were severely disorganized and lacked a recognizable outer plexiform layer (OPL). Although the gene was effectively silenced by P6, DYNC1H1 remnants persisted and aggregated together with rhodopsin, PDE6 and centrin-2-positive centrosomes in the outer nuclear layer. As photoreceptor degeneration is delayed in the Dync1h1F/F;Six3Cre retina periphery, retinal lamination and outer segment elongation are in part preserved. DYNC1H1 strongly persisted in the inner plexiform layer (IPL) beyond P16 suggesting lack of clearance of the DYNC1H1 polypeptide. This persistence of DYNC1H1 allows horizontal, rod bipolar, amacrine and ganglion cells to survive past P12. The results show that cytoplasmic dynein is essential for retina lamination, nuclear positioning, vesicular trafficking of photoreceptor membrane proteins and inner/outer segment elaboration.

Engaging patients and parents to improve mental health intervention for youth with rheumatological disease.

BACKGROUND: Mental health disorders are common in youth with rheumatological disease yet optimal intervention strategies are understudied in this population. We examined patient and parent perspectives on mental health intervention for youth with rheumatological disease. METHODS: We conducted a mixed methods cross-sectional study, via anonymous online survey, developed by researchers together with patient/parent partners, to quantitatively and qualitatively examine youth experiences with mental health services and resources in North America. Patients ages 14-24 years with juvenile idiopathic arthritis, juvenile dermatomyositis, or systemic lupus erythematous, and parents of patients ages 8-24 with these diseases were eligible (not required to participate in pairs). Participants self-reported mental health problems (categorized into clinician-diagnosed disorders vs self-diagnosed symptoms) and treatments (e.g. therapy, medications) received for the youth. Multivariate linear regression models compared patient and parent mean Likert ratings for level of: i) comfort with mental health providers, and ii) barriers to seeking mental health services, adjusting for potential confounders (patient age, gender, disease duration, and patient/parent visual analog score for disease-related health). Participants indicated usefulness of mental health resources; text responses describing these experiences were analyzed by qualitative description. RESULTS: Participants included 123 patients and 324 parents. Patients reported clinician-diagnosed anxiety (39%) and depression (35%); another 27 and 18% endorsed self-diagnosed symptoms of these disorders, respectively. 80% of patients with clinician-diagnosed disorders reported receiving treatment, while 11% of those with self-diagnosed symptoms reported any treatment. Patients were less comfortable than parents with all mental health providers. The top two barriers to treatment for patients and parents were concerns about mental health providers not understanding the rheumatological disease, and inadequate insurance coverage. Over 60% had used patient mental health resources, and over 60% of these participants found them to be helpful, although text responses identified a desire for resources tailored to patients with rheumatological disease. CONCLUSION: Self-reported mental health problems are prevalent for youth in this sample with rheumatological disease, and obstacles to mental health treatment include disease-related and logistic factors. Strategies are needed to improve acceptance and accessibility of mental health intervention, including routine mental health screening and availability of disease-specific mental health resources.

Evolution of cryptic coloration in ectoparasites.

Cryptic coloration is a classic example of evolution by natural selection. However, it has been studied almost exclusively in predator-prey systems, despite the fact that it may evolve in other groups, such as ectoparasites. The principle defense of hosts against ectoparasites is grooming behavior, which has a visual component. Host-imposed selection should lead to the evolution of background matching if it helps ectoparasites escape from grooming. Here we use sister taxa comparisons to show that avian feather lice (Phthiraptera: Ischnocera) have evolved coloration that matches the host's plumage, except in the case of head lice, which are protected from grooming. We also show covariation of parasite and host color within a single species of louse. Thus, cryptic coloration has evolved both within and between species of feather lice. Other examples of the evolution of crypsis presumably exist among the 70,000 known species of ectoparasites that collectively represent five animal phyla.

Neuronal nicotinic alpha7 receptors modulate early neutrophil infiltration to sites of skin inflammation.

BACKGROUND: A major site of initiation of inflammatory responses upon physical perturbation(s) and infection by invading organisms is the skin. Control of responses in this organ is, in part, modulated by the neuronal nicotinic acetylcholine receptor (nAChR) alpha7. METHODS: To further investigate the role of alpha7 in skin inflammatory responses, a local inflammatory response was induced by topical application of croton oil to the ear skin of wild-type (alpha7WT) and alpha7 knock-out (alpha7KO) mice. Cells infiltrating the inflamed tissue were characterized by flow cytometry and RNA analysis. RESULTS: Six hours following croton oil application, analysis of infiltrating cells showed that the alpha7KO mice exhibited a significantly enhanced number of cells, and specifically, of Ly6G positive neutrophils. Macrophage and lymphocyte infiltration was equivalent in the alpha7KO and alpha7WT mice. RNA analysis showed that IL-1beta and IL-6 were increased significantly in the infiltrating cells of the alpha7KO mouse, although TNF failed to reach significance. In contrast, resident cells of the skin exhibited no differences in these cytokines between genotypes. Both resident and infiltrating cell populations from alpha7KO mice did show elevated message levels for the adhesion protein ICAM1. Measurement of chemokines revealed enhanced expression of the skin-related CCL27 by resident cells in alpha7KO mice. Further, we demonstrate that the population of Ly6G+ neutrophils at the croton oil-inflamed skin site expresses low levels of CCR10, a receptor for CCL27 normally associated with lymphocytes. CONCLUSION: nAChRalpha7 in the skin can impact on early local inflammatory responses mediated through a novel population of neutrophils that are Ly6G+CCR10lo.

Screening Tool for the Assessment of Malnutrition in Pediatrics (STAMP) in the Electronic Health Record: A Validation Study.

BACKGROUND: The impact of malnutrition on pediatric patients in the acute care setting is significant. Hospitalized patients with malnutrition have been shown to have poor clinical outcomes. Nutrition screening is the first critical step in identifying and treating malnutrition. Although several pediatric nutrition screening tools exist, none incorporate both electronic health record (EHR) compatibility and the recommended indicators of pediatric malnutrition, a gap recently identified in a systematic review by the Academy of Nutrition and Dietetics. The aim of this study was to prove the validity of a new version of Screening Tool for the Assessment of Malnutrition in Pediatrics (STAMP), EHR-STAMP, modified for incorporation into the EHR and inclusion of updated pediatric malnutrition indicators. METHODS: An interprofessional team modified the existing STAMP for integration into the EHR. Audits were performed by the research dietitian to assess accuracy and provide feedback for continuous improvement of the tool design. RESULTS: A total of 3553 pediatric inpatients were studied from August 2017 to May 2019. Accuracy, sensitivity, and specificity improved with each modification to the EHR-STAMP. The final version of the EHR-STAMP found 85% accuracy, 89% sensitivity, and 97% specificity, with a positive predictive value of 60% and a negative predictive value of 94%. CONCLUSION: The EHR-STAMP is a highly reliable tool in the screening of nutrition risk for pediatric hospitalized patients. The tool is easy to use, EHR compatible, and incorporates the current indicators recommended for assessing pediatric malnutrition.

Mesoscale Reaction-Diffusion Phenomena Governing Lignin-First Biomass Fractionation.

Lignin solvolysis from the plant cell wall is the critical first step in lignin depolymerization processes involving whole biomass feedstocks. However, little is known about the coupled reaction kinetics and transport phenomena that govern the effective rates of lignin extraction. Here, we report a validated simulation framework that determines intrinsic, transport-independent kinetic parameters for the solvolysis of lignin, hemicellulose, and cellulose upon incorporation of feedstock characteristics for the methanol-based extraction of poplar as an example fractionation process. Lignin fragment diffusion is predicted to compete on the same time and length scales as reactions of lignin within cell walls and longitudinal pores of typical milled particle sizes, and mass transfer resistances are predicted to dominate the solvolysis of poplar particles that exceed approximately 2 mm in length. Beyond the approximately 2 mm threshold, effectiveness factors are predicted to be below 0.25, which implies that pore diffusion resistances may attenuate observable kinetic rate measurements by at least 75 % in such cases. Thus, researchers are recommended to conduct kinetic evaluations of lignin-first catalysts using biomass particles smaller than approximately 0.2 mm in length to avoid feedstock-specific mass transfer limitations in lignin conversion studies. Overall, this work highlights opportunities to improve lignin solvolysis by genetic engineering and provides actionable kinetic information to guide the design and scale-up of emerging biorefinery strategies.