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Metabolic pathway regulates cell fate Lineage-specific regulators direct cell fate decisions, but the precise mechanisms are not well known. Using an in vivo chemical suppressor screen of a bloodless zebrafish mutant, Rossmann et al. show that the lineage-specific chromatin factor tif1γ directly regulates mitochondrial genes to drive red blood cell differentiation. Loss of tif1γ reduces coenzyme Q synthesis and function, impeding mitochondrial respiration and leading to epigenetic alterations and repression of erythropoiesis. The loss of blood in the mutant fish can be rescued by the addition of coenzyme Q. This work establishes a mechanism by which a chromatin factor tunes a metabolic pathway in a tissue-specific manner. Science , this issue p. 716

Undergraduate students participating in the UCLA Undergraduate Research Consortium for Functional Genomics (URCFG) have conducted a two-phased screen using RNA interference (RNAi) in combination with fluorescent reporter proteins to identify genes important for hematopoiesis in Drosophila. This screen disrupted the function of approximately 3500 genes and identified 137 candidate genes for which loss of function leads to observable changes in the hematopoietic development. Targeting RNAi to maturing, progenitor, and regulatory cell types identified key subsets that either limit or promote blood cell maturation. Bioinformatic analysis reveals gene enrichment in several previously uncharacterized areas, including RNA processing and export and vesicular trafficking. Lastly, the participation of students in this course-based undergraduate research experience (CURE) correlated with increased learning gains across several areas, as well as increased STEM retention, indicating that authentic, student-driven research in the form of a CURE represents an impactful and enriching pedagogical approach.

Genome-wide association studies identify genomic variants associated with human traits and diseases. Most trait-associated variants are located within cell-type-specific enhancers, but the molecular mechanisms governing phenotypic variation are less well understood. Here, we show that many enhancer variants associated with red blood cell (RBC) traits map to enhancers that are co-bound by lineage-specific master transcription factors (MTFs) and signaling transcription factors (STFs) responsive to extracellular signals. The majority of enhancer variants reside on STF and not MTF motifs, perturbing DNA binding by various STFs (BMP/TGF-β-directed SMADs or WNT-induced TCFs) and affecting target gene expression. Analyses of engineered human blood cells and expression quantitative trait loci verify that disrupted STF binding leads to altered gene expression. Our results propose that the majority of the RBC-trait-associated variants that reside on transcription-factor-binding sequences fall in STF target sequences, suggesting that the phenotypic variation of RBC traits could stem from altered responsiveness to extracellular stimuli.

To test for differences in DISE findings in children sedated with propofol versus dexmedetomidine. We hypothesized that the frequency of ≥ 50% obstruction would be higher for the propofol than dexmedetomidine group at the dynamic levels of the airway (velum, lateral walls, tongue base, and supraglottis) but not at the more static adenoid level. A single-center retrospective review was performed on children age 1–18 years with a diagnosis of sleep disordered breathing or obstructive sleep apnea (OSA) who underwent DISE from July 2014 to Feb 2019 scored by the Chan-Parikh scale sedated with either propofol or dexmedetomidine (with or without ketamine). Logistic regression was used to test for a difference in the odds of ≥ 50% obstruction (Chan-Parikh score ≥ 2) at each airway level with the use of dexmedetomidine vs. propofol, adjusted for age, sex, previous tonsillectomy, surgeon, positional OSA, and ketamine co-administration. Of 117 subjects, 57% were sedated with propofol and 43% with dexmedetomidine. Subjects were 60% male, 66% Caucasian, 31% obese, 38% syndromic, and on average 6.5 years old. Thirty-three percent had severe OSA and 41% had previous tonsillectomy. There was no statistically significant difference in the odds of ≥ 50% obstruction between the two anesthetic groups at any level of the airway with or without adjustment for potential confounders. We did not find a significant difference in the degree of upper airway obstruction on DISE in children sedated with propofol versus dexmedetomidine. Prospective, randomized studies would be an important next step to confirm these findings.

Background Facial paresis is one of the complications after treatment for vestibular schwannoma (VS). Acupuncture has been used for Bell palsy but not in iatrogenic facial paresis. The objective of this study is to measure the efficacy of using acupuncture for iatrogenic facial nerve palsy and patients' satisfaction. Methods This is a single-center retrospective study with patients from 2007–2019 received treatment for newly diagnosed or recurrent VS. Some patients who suffered facial paresis after surgery had self-initiated acupuncture. All patients who had facial paresis were included. Their facial nerve status before and immediately after surgery, postoperative 6 months and 12 months, were recorded. Those who received acupuncture also answered 6- and 12-month patient satisfaction surveys over the phone. Adverse effects were also assessed. Results There were 123 patients in this period. Of these, 29 patients had iatrogenic facial paresis and 23 of them received acupuncture. There was significant improvement of facial paresis for the acupuncture group compared with the nonacupuncture group at 6 and 12 months. More than 80% of patients who received acupuncture were satisfied. They had motor improvement and experienced less pain and tightness. No adverse effects were reported. Conclusions Acupuncture for postresection VS facial paresis seemed to speed up its recovery. Both patients' recovery and satisfaction were good after acupuncture, and it seemed to be a safe procedure in trained hands.

Tricin, one of the flavones present in edible Poaceae species, was shown to interfere with intestinal inflammatory-related carcinogenesis and suppress metastasis in colon cancer mice models. Those botanical foods and medicinal herbs which contain high content of tricin may be considered as health supplements for colon health. Hence, the present study aimed to identify and quantify the content of tricin in various medicinal herbs, edible botanicals and some agricultural by-products by LC-MS. A list of “top 10 tricin-rich botanicals/medicinal herbs” was built. From the results, the top three high tricin content botanicals are the dried culms of Triticum aestivum (wheat straw), dried culms of Oryza sativa (rice straw) and mature fruits of Imperata cylindrica. Furthermore, a simple, straightforward isolation method has been developed to isolate tricin from wheat straw which achieved 50% isolation rate (percentage yield of 0.05% w/w) with purity of not less than 98%.

Positional obstructive sleep apnea (POSA)-defined as obstructive sleep apnea twice as severe supine than nonsupine-may offer clues to the underlying pattern of upper airway collapse in children. We compared drug-induced sleep endoscopy (DISE) findings in children with and without POSA. We hypothesized that children with POSA would have significantly higher obstruction at the gravity-dependent palate and tongue base but not at the adenoid, lateral wall, or supraglottis.Retrospective case series.Tertiary pediatric hospital.We included children aged 1 to 12 years with obstructive sleep apnea diagnosed by polysomnography who underwent DISE from July 2014 to February 2019. Scores were dichotomized as ≥50% obstruction (Chan-Parikh 2 or 3) vs50% obstruction (Chan-Parikh 0 or 1).Of 99 children included, 32 (32%) had POSA and 67 (68%) did not. Children with POSA did not differ from children without POSA in age, overall apnea-hypopnea index, sex, race, syndromic diagnoses, obesity, or history of adenotonsillectomy. In logistic regression models, odds of ≥50% obstruction were significantly higher at the tongue base (odds ratio, 2.77; 95% CI, 1.04-7.39) after adjustment for age, sex, obesity, previous adenotonsillectomy, and syndrome. No difference was noted at the adenoid, velum, lateral wall, or supraglottis.POSA was associated with higher odds of obstruction on DISE at the tongue base but not at other levels.

To test for differences in DISE findings in children sedated with propofol versus dexmedetomidine. We hypothesized that the frequency of ≥ 50% obstruction would be higher for the propofol than dexmedetomidine group at the dynamic levels of the airway (velum, lateral walls, tongue base, and supraglottis) but not at the more static adenoid level.A single-center retrospective review was performed on children age 1-18 years with a diagnosis of sleep disordered breathing or obstructive sleep apnea (OSA) who underwent DISE from July 2014 to Feb 2019 scored by the Chan-Parikh scale sedated with either propofol or dexmedetomidine (with or without ketamine). Logistic regression was used to test for a difference in the odds of ≥ 50% obstruction (Chan-Parikh score ≥ 2) at each airway level with the use of dexmedetomidine vs. propofol, adjusted for age, sex, previous tonsillectomy, surgeon, positional OSA, and ketamine co-administration.Of 117 subjects, 57% were sedated with propofol and 43% with dexmedetomidine. Subjects were 60% male, 66% Caucasian, 31% obese, 38% syndromic, and on average 6.5 years old. Thirty-three percent had severe OSA and 41% had previous tonsillectomy. There was no statistically significant difference in the odds of ≥ 50% obstruction between the two anesthetic groups at any level of the airway with or without adjustment for potential confounders.We did not find a significant difference in the degree of upper airway obstruction on DISE in children sedated with propofol versus dexmedetomidine. Prospective, randomized studies would be an important next step to confirm these findings.

Understanding in-vivo mechanisms of erythropoiesis is critical for directed differentiation approaches to treat blood disorders such as leukemias. Zebrafish moonshine (mon) mutant embryos defective for the conserved transcriptional intermediary factor 1 gamma (tif1γ) do not specify enough erythroid progenitors due to a transcription elongation block characterized by aberrantly paused RNA polymerase II. To elucidate the TIF1γ-mediated mechanisms in erythroid differentiation, we performed a chemical suppressor screen using 3,100 compounds and identified inhibitors of the essential mitochondrial pyrimidine synthesis enzyme dihydroorotate dehydrogenase (DHODH). Leflunomide as well as the structurally unrelated DHODH inhibitor brequinar rescue the formation of erythroid progenitors in 61% (38/62) and 68% (50/74) of mon embryos, respectively. Beyond changes in nucleotide metabolism, in-vivo metabolic analyses revealed low levels of TCA cycle metabolites which were functionally linked to a reduced oxygen consumption rate. In addition, an increased 2HG/αKG ratio was associated with higher histone methylation states at H3K27, H3K36 and H4K20 as assessed by quantitative targeted mass spectrometry, which may contribute to the erythroid differentiation block upon tif1γ loss. DHODH is the only pyrimidine de novo synthesis enzyme located in mitochondria and its activity is coupled to that of the electron transport chain (ETC) via coenzyme Q (CoQ). Rotenone, a potent ETC complex I inhibitor reversed the rescue by DHODH inhibition in mon embryos. Through parallel genome-wide transcriptome and chromatin immunoprecipitation analyses, we found that genes encoding CoQ metabolic enzymes are direct TIF1γ targets. Treatment with the CoQ analog decylubiquinone rescued erythroid progenitors in 26% (33/126) of mon embryos. These results demonstrate a tight coordination of nucleotide and mitochondrial metabolism as a key function of tif1γ-dependent transcription and reveal that TIF1γ activity regulates a metabolic program that drives cell fate decisions in the early blood lineage. Our work highlights the importance of the plasticity achieved by transcription regulatory processes such as transcription elongation for metabolic processes during lineage differentiation and could have therapeutic potential for blood diseases. Citation Format: Marlies P. Rossmann, Karen Hoi, Victoria Chan, Brian J. Abraham, Song Yang, James Mullahoo, Malvina Papanastasiou, Ilaria Elia, Sejal Vyas, Partha P. Nag, Lucas B. Sullivan, Julie R. Perlin, Elliott J. Hagedorn, Sara Hetzel, Raha Weigert, Curtis R. Warren, Bilguujin Dorjsuren, Eugenia Custo Greig, Chad A. Cowan, Stuart L. Schreiber, Richard A. Young, Alexander Meissner, Marcia Haigis, Steven A. Carr, Leonard I. Zon. Transcriptional regulation of mitochondrial metabolism by TIF1γ drives erythroid progenitor differentiation [abstract]. In: Abstracts: AACR Special Virtual Conference on Epigenetics and Metabolism; October 15-16, 2020; 2020 Oct 15-16. Philadelphia (PA): AACR; Cancer Res 2020;80(23 Suppl):Abstract nr PR04.

Understanding in-vivo mechanisms of erythropoiesis is critical for directed differentiation approaches to treat blood disorders. Zebrafish moonshine (mon) mutant embryos defective for the conserved transcriptional intermediary factor 1 gamma (tif1γ) do not specify enough erythroid progenitors. To elucidate the TIF1γ-mediated mechanisms in erythroid differentiation, we performed a chemical suppressor screen using 3,100 compounds and identified inhibitors of the essential mitochondrial pyrimidine synthesis enzyme dihydroorotate dehydrogenase (DHODH). Leflunomide as well as the structurally unrelated DHODH inhibitor brequinar rescue the formation of erythroid progenitors in 61% (38/62) and 68% (50/74) of mon embryos, respectively. Beyond changes in nucleotide metabolism, in-vivo metabolic analyses revealed low levels of TCA cycle metabolites which were functionally linked to a reduced oxygen consumption rate. In addition, an increased 2HG/αKG ratio was associated with higher histone methylation states at H3K27, H3K36 and H4K20 as assessed by quantitative targeted mass spectrometry, which may contribute to the erythroid differentiation block upon tif1γ loss. DHODH is the only pyrimidine de novo synthesis enzyme located in mitochondria and its activity is coupled to that of the electron transport chain (ETC) via coenzyme Q (CoQ). Rotenone, a potent ETC complex I inhibitor reversed the rescue by DHODH inhibition in mon embryos. Through parallel genome-wide transcriptome and chromatin immunoprecipitation analyses, we found that genes encoding CoQ metabolic enzymes are direct TIF1γ targets. Treatment with the CoQ analog decylubiquinone rescued erythroid progenitors in 26% (33/126) of mon embryos. Our work highlights the importance of transcription regulatory processes for tuning metabolism during lineage differentiation and could have therapeutic implications.

Heterocycles play an important role in many biological processes and are widespread among natural products. Oxazole-containing natural products possess a broad range of bioactivities and are of great interest in the pharmaceutical and agrochemical industries. Herein, the biosynthetic routes to the oxazole-containing phthoxazolins and the bis(benzoxaozle) AJI9561, were investigated. Phthoxazolins A-D are a group of oxazole trienes produced by a polyketide synthase-nonribosomal peptide synthetase (PKS-NRPS) pathway in Streptomyces sp. KO-7888 and Streptomyces sp. OM-5714. The phthoxazolin pathway was used as a model to study 5-oxazole and primary amide formation in PKS-NRPS pathways. An unusually large gene cluster for phthoxazolin biosynthesis was identified from the complete genome sequence of the producer strains and various gene deletions were performed to define the minimal gene cluster. PhoxP was proposed to encode an ATP-dependent cyclodehydratase for 5-oxazole formation on an enzyme-bound N-formylglycylacyl-intermediate, and its deletion abolished phthoxazolin production. In vitro reconstitution of the early steps of phthoxazolin biosynthesis was attempted to validate the role of PhoxP, but was unsuccessful. Furthermore, Orf3515, a putative flavin-dependent monooxygenase coded by a remote gene, was proposed to hydroxylate glycine-extended polyketide-peptide chain(s) at the α-position to yield phthoxazolins with the primary amide moiety. On the other hand, an in vitro approach was employed to establish the enzymatic logic of the biosynthesis of AJI9561, a bis(benzoxazole) antibiotic isolated from Streptomyces sp. AJ9561. The AJI9561 pathway was reconstituted using the precursors 3-hydroxyanthranilic acid and 6-methylsalicylic acid and five purified enzymes previously identified from the pathway as key enzymes for benzoxazole formation, including two adenylation enzymes for precursor activation, an acyl carrier protein (ACP), a 3-oxoacyl-ACP synthase and an amidohydrolase-like cyclase. Intermediates and shunt products isolated from enzymatic reactions containing different enzyme and precursor combinations were assessed for their competence for various steps of AJI9561 biosynthesis. Further bioinformatic analysis and in silico modelling of the amidohydrolase-like cyclase shed light on the oxazole cyclisation that represents a novel catalytic function of the amidohydrolase superfamily., Henry Lester Trust, Herchel Smith Foundation

Recently, the mankind has realized that unless environment is protected, he himself will be threatened by the over consumption of natural resource as well as substantial reduction of fresh air produced in the world. Conservation of forests and optimal utilization of agricultural and other renewable resources like solar and wind energies, and recently, tidal energy have become important topics worldwide. In such concern, the use of renewable resources such as plant and animal based fiber-reinforced polymeric composites, has been becoming an important design criterion for designing and manufacturing components for all industrial products. Research on biodegradable polymeric composites can contribute to green and safe environment to some extent. In the biomedical and bioengineered field, the use of natural fiber mixed with biodegradable and bioresorbable polymers can produce joints and bone fixtures to alleviate pain for patients. In this chapter, a comprehensive review on different kinds of natural fiber composites will be given. Their potential in future development of different kinds of engineering and domestic products will also be discussed in detail.

Understanding the cell-autonomous as well as niche contributions governing erythropoiesis is critical for directed differentiation approaches of hematopoietic stem cells into differentiated red blood cells (RBCs) to treat blood disorders such as anemias and leukemias. Transcriptional intermediary factor 1 gamma (TIF1γ) is essential for erythropoiesis from zebrafish to mammals. Zebrafish moonshine mutant embryos defective for tif1γ do not make red blood cells (RBCs) due to a transcription elongation block characterized by aberrantly paused RNA polymerase II. Loss of factors involved in transcription elongation control, PAF1 and spt5, rescues the moonshine RBC defect. To elucidate the TIF1γ-mediated mechanisms in erythroid differentiation, we have performed a high-content chemical suppressor screen in the bloodless moonshine mutant using 3,500 compounds. Among the suppressors, we identified leflunomide, an inhibitor of dihydroorotate dehydrogenase (DHODH), an essential enzyme for de novo pyrimidine synthesis. Leflunomide as well as the structurally unrelated DHODH inhibitor brequinar both rescue the formation of primitive erythroid cells in 61% (38/62) and 68% (50/74) of moonshine embryos, respectively. Blastula transplant experiments revealed that tif1γ, in addition to its cell-autonomous role, plays a role in the hematopoietic niche for RBC development. Through in-vivo metabolomics analyses we have identified nucleotide metabolism as the most significantly altered process in moonshine mutants, including elevated levels of uridine monophosphate and low levels of nicotinamide adenine dinucleotide (NAD+). Low NAD+ levels are accompanied by a reduced oxygen consumption rate in tif1γ-depleted embryos by Seahorse analysis. In support, genome-wide transcriptome analysis coupled with chromatin immunoprecipitation studies revealed genes encoding coenzyme Q (CoQ) metabolic enzymes as direct TIF1γ targets. DHODH is the only enzyme of the pyrimidine de novo synthesis pathway located on the inner mitochondrial membrane and its activity is coupled to that of the electron transport chain (ETC). Rotenone, a potent ETC complex I inhibitor reverses the rescue of the blood defect by DHODH inhibition in moonshine embryos. Since DHODH function is linked to mitochondrial oxidative phosphorylation via CoQ activity, we asked whether alterations in mitochondrial metabolism might be causal for the RBC defect in moonshine mutants. Indeed, treatment with the CoQ analog decylubiquinone results in rescue of βe3 globin expression in 26% (33/126) of moonshine embryos. These results demonstrate a tight coordination of nucleotide and mitochondrial metabolism as a key function of tif1γ-dependent transcription and reveal that TIF1γ activity regulates a metabolic program that drives cell fate decisions in the early blood lineage. Our work highlights the importance of the plasticity achieved by transcription regulatory processes such as transcription elongation for metabolic processes during lineage differentiation and could have therapeutic potential for blood diseases and consequences for erythroid differentiation protocols. Disclosures Zon: Fate Therapeutics: Equity Ownership; Scholar Rock: Equity Ownership; CAMP4: Equity Ownership.

Disputes have been identified as one of the epidemics of the construction industry. Many studies have found that risks, uncertainties, inadequate contract documentation, and behavioral factors are notable dispute sources. Many have described disputes with reference to the subject matter. This approach is pragmatic but has not yet lead to any form of conceptualization. The study contributes to the construction dispute research domain in (1) proposing an anatomy of construction disputes, (2) identifying the key factors contributing to the happening of construction disputes, and (3) providing an example on the use of the anatomy through a dispute occurrence likelihood evaluation exercise. The proposed anatomy distinguishes two types of construction dispute: contractual and speculative. Contract incompleteness is the root cause and underpins both types of construction disputes. In addition, task and people factors fuel contractual and speculative disputes, respectively. The proposed anatomy is arrange...

Fenton and photoassisted Fenton degradation of ordinary hydrophobic cross-linked polystyrene microspheres and sulfonated polystyrene beads (DOWEX 50WX8) have been attempted. While the Fenton process was not able to degrade these polystyrene materials, photoassisted Fenton reaction (mediated by broad-band UV irradiation from a 250 W Hg(Xe) light source) was found to be efficient in mineralizing cross-linked sulfonated polystyrene materials. The optimal loadings of the Fe(III) catalyst and the H(2)O(2) oxidant for such a photoassisted Fenton degradation were found to be 42 μmol-Fe(III) and 14.1 mmol-H(2)O(2) per gram of the sulfonated polystyrene material. The initial pH for the degradation was set at pH 2.0. This photoassisted Fenton degradation process was also able to mineralize commonly encountered polystyrene wastes. After a simple sulfonation pretreatment, a mineralization efficiency of >99% (by net polymer weight) was achieved within 250 min. The mechanism of this advanced oxidative degradation process was investigated. Sulfonate groups introduced to the surface of the treated polystyrene polymer chains were capable of rapidly binding the cationic Fe(III) catalyst, probably via a cation-exchange mechanism. Such a sorption of the photoassisted Fenton catalyst was crucial to the heterogeneous degradation process.

Briot et al. show that inflammatory lipids deriving from a high-fat diet suppress NOTCH1 expression and signaling in adult arterial endothelium and propose that reduction of endothelial NOTCH1 is a predisposing factor in the onset of atherosclerosis., Although much progress has been made in identifying the mechanisms that trigger endothelial activation and inflammatory cell recruitment during atherosclerosis, less is known about the intrinsic pathways that counteract these events. Here we identified NOTCH1 as an antagonist of endothelial cell (EC) activation. NOTCH1 was constitutively expressed by adult arterial endothelium, but levels were significantly reduced by high-fat diet. Furthermore, treatment of human aortic ECs (HAECs) with inflammatory lipids (oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine [Ox-PAPC]) and proinflammatory cytokines (TNF and IL1β) decreased Notch1 expression and signaling in vitro through a mechanism that requires STAT3 activation. Reduction of NOTCH1 in HAECs by siRNA, in the absence of inflammatory lipids or cytokines, increased inflammatory molecules and binding of monocytes. Conversely, some of the effects mediated by Ox-PAPC were reversed by increased NOTCH1 signaling, suggesting a link between lipid-mediated inflammation and Notch1. Interestingly, reduction of NOTCH1 by Ox-PAPC in HAECs was associated with a genetic variant previously correlated to high-density lipoprotein in a human genome-wide association study. Finally, endothelial Notch1 heterozygous mice showed higher diet-induced atherosclerosis. Based on these findings, we propose that reduction of endothelial NOTCH1 is a predisposing factor in the onset of vascular inflammation and initiation of atherosclerosis.

A workflow that covers business processes and spatial processes requires a geographic information system (GIS) and an enterprise information system for capturing, representing and computing these processes. This paper first discusses how the respective information systems can capture business processes and spatial processes. It then introduces a lifecycle for integrated workflows: Pieces of workload are shared between the GIS and the enterprise information system in a sequenced manner. Here, web services are suggested to carry out the necessary communication between the two information systems. They help to overcome software architectures that separate information systems. In this paper, the workflow lifecycle is applied to the integrated use of a GIS and a customer relationship management system (CRM) in an emergency management scenario. A prototype is presented as a proof-of-concept.