232 results on '"Scott RW"'
Search Results
2. Resource: Scalable whole genome sequencing of 40,000 single cells identifies stochastic aneuploidies, genome replication states and clonal repertoires
- Author
-
Bojilova, Vatrt-Watts S, Underhill Mt, Emma Laks, Taghiyar Mj, Stephen Pleasance, Brimhall J, Samuel Aparicio, Chan Sy, Andrew McPherson, Richard D. Moore, Masud T, Ngo J, Costa Dd, Wang B, Abrar N, Martin L, Christian Steidl, Marco A. Marra, Elizabeth A. Chavez, Coope Rjn, Lee, Farhia Kabeer, Nielsen C, Yussanne Ma, Grewal D, Golovko O, Matt Wiens, Adi Steif, Carl L. Hansen, Hans Zahn, Pascale Walters, Sohrab P. Shah, Peter Eirew, Daniel Lai, Andrew J. Mungall, de Algara Tr, Scott Rw, Steven S.S. Poon, Justina Biele, Chan T, Leung S, Maia A. Smith, Huebner C, and Richard Corbett
- Subjects
Whole genome sequencing ,0303 health sciences ,education.field_of_study ,Mutation ,Population ,Genomics ,Computational biology ,Biology ,medicine.disease_cause ,Genome ,DNA sequencing ,Replication (computing) ,03 medical and health sciences ,0302 clinical medicine ,030220 oncology & carcinogenesis ,medicine ,education ,Mitosis ,030304 developmental biology - Abstract
SummaryEssential features of cancer tissue cellular heterogeneity such as negatively selected genome topologies, sub-clonal mutation patterns and genome replication states can only effectively be studied by sequencing single-cell genomes at scale and high fidelity. Using an amplification-free single-cell genome sequencing approach implemented on commodity hardware (DLP+) coupled with a cloud-based computational platform, we define a resource of 40,000 single-cell genomes characterized by their genome states, across a wide range of tissue types and conditions. We show that shallow sequencing across thousands of genomes permits reconstruction of clonal genomes to single nucleotide resolution through aggregation analysis of cells sharing higher order genome structure. From large-scale population analysis over thousands of cells, we identify rare cells exhibiting mitotic mis-segregation of whole chromosomes. We observe that tissue derived scWGS libraries exhibit lower rates of whole chromosome anueploidy than cell lines, and loss of p53 results in a shift in event type, but not overall prevalence in breast epithelium. Finally, we demonstrate that the replication states of genomes can be identified, allowing the number and proportion of replicating cells, as well as the chromosomal pattern of replication to be unambiguously identified in single-cell genome sequencing experiments. The combined annotated resource and approach provide a re-implementable large scale platform for studying lineages and tissue heterogeneity.
- Published
- 2018
- Full Text
- View/download PDF
3. Recombinant Human Protease Nexin-1 Prevents Articular Cartilage-Degradation in the Rabbit
- Author
-
Shatzen Em, Stevens P, and Scott Rw
- Subjects
Urokinase ,Protease ,Plasmin ,Catabolism ,Chemistry ,Cartilage ,medicine.medical_treatment ,Inflammation ,Matrix metalloproteinase ,Molecular biology ,Glycosaminoglycan ,medicine.anatomical_structure ,Biochemistry ,medicine ,medicine.symptom ,medicine.drug - Abstract
Cartilage degradation is mediated by activated matrix metalloproteinases (MMP). Since the plasmin/plasminogen cascade may activate latent MMP during cartilage catabolism, we determined if protease nexin-1 (PN-1), an inhibitor of plasminogen, plasmin, and urokinase could prevent cartilage degradation. Using a rabbit model, we induced cartilage glycosaminoglycan (GAG) loss by intraarticular (IA) injection of IL-1 beta and bFGF. PN-1 was given IA for 4 days, once before IL-1 beta/bFGF and daily for 3 days. Three days after IL-1 beta/bFGF, we determined GAG loss. PN-1 significantly inhibited GAG loss at 2.8, 2.5 mg, and 2.0 mg/knee (p < 0.03). These data suggest the role of the plasmin/plasminogen enzymatic cascade in the cartilage catabolism that occurs during IL-1-induced inflammation and demonstrates the potential of PN-1 to prevent cartilage degradation.
- Published
- 1993
- Full Text
- View/download PDF
4. Intracoronary photodynamic therapy reduces neointimal growth without suppressing re-endothelialisation in a porcine model.
- Author
-
Waksman R, Leitch IM, Roessler J, Yazdi H, Seabron R, Tio F, Scott RW, Grove RI, Rychnovsky S, Robinson B, Pakala R, and Cheneau E
- Abstract
OBJECTIVE: To examine the effects of intracoronary PhotoPoint photodynamic therapy (PDT) with a new photosensitiser, MV0611, in the overstretch balloon and stent porcine models of restenosis. METHODS: 28 pigs were injected with 3 mg/kg of MV0611 systemically 4 h before the procedure. Animals were divided into either the balloon overstretch injury (BI) group (n = 19) or the stented group (n = 9). After BI, a centred delivery catheter was positioned in the artery to cover the injured area, and light (532 nm, 125 J/cm(2)) was applied to activate the drug (n = 10). Control arteries (n = 9) were not activated by light. In the stented group, the drug was light activated before stent deployment. Serial sections of vessels were processed 14 days after treatment in the BI group and 30 days after treatment in the stented group for histomorphometric or immunohistochemical analysis. RESULTS: Intracoronary PDT significantly reduced intimal thickness in both BI and stented arteries (about 65%: 0.22 (SEM 0.05) mm v 0.62 (0.05) mm, p < 0.01; and about 26%: 0.40 (0.04) mm v 0.54 (0.04) mm, p < 0.01, respectively). PDT increased luminal area by
- Published
- 2006
- Full Text
- View/download PDF
5. The ontogeny of a 57-Kd cationic antimicrobial protein of human polymorphonuclear leukocytes: localization to a novel granule population
- Author
-
Pereira, HA, primary, Spitznagel, JK, additional, Winton, EF, additional, Shafer, WM, additional, Martin, LE, additional, Guzman, GS, additional, Pohl, J, additional, Scott, RW, additional, Marra, MN, additional, and Kinkade, JM Jr, additional
- Published
- 1990
- Full Text
- View/download PDF
6. Case of Bronchorrh a Aestiva, or Hay-fever: with Remarks
- Author
-
Scott Rw
- Subjects
medicine.medical_specialty ,business.industry ,Family medicine ,General Engineering ,medicine ,MEDLINE ,General Earth and Planetary Sciences ,Hay fever ,General Medicine ,medicine.disease ,business ,Data science ,General Environmental Science - Published
- 1842
- Full Text
- View/download PDF
7. On the Employment of Digitalis during the Premonitory Symptoms of Sthenic Epilepsy
- Author
-
Scott Rw
- Subjects
medicine.medical_specialty ,biology ,business.industry ,General Engineering ,Alternative medicine ,Digitalis ,Articles ,General Medicine ,biology.organism_classification ,Bioinformatics ,medicine.disease ,Epilepsy ,medicine ,General Earth and Planetary Sciences ,Psychiatry ,business ,General Environmental Science - Published
- 1844
- Full Text
- View/download PDF
8. Brain pericytes and perivascular fibroblasts are stromal progenitors with dual functions in cerebrovascular regeneration after stroke.
- Author
-
Bernier LP, Hefendehl JK, Scott RW, Tung LW, Lewis CA, Soliman H, Simm S, Dissing-Olesen L, Hofmann J, Guo D, DeMeglio M, Rossi FM, Underhill TM, and MacVicar BA
- Abstract
Functional revascularization is key to stroke recovery and requires remodeling and regeneration of blood vessels around which is located the brain's only stromal compartment. Stromal progenitor cells (SPCs) are critical for tissue regeneration following injury in many organs, yet their identity in the brain remains elusive. Here we show that the perivascular niche of brain SPCs includes pericytes, venular smooth muscle cells and perivascular fibroblasts that together help cerebral microvasculature regenerate following experimental stroke. Ischemic injury triggers amplification of pericytes and perivascular fibroblasts in the infarct region where they associate with endothelial cells inside a reactive astrocyte border. Fate-tracking of Hic1
+ SPCs uncovered a transient functional and transcriptional phenotype of stroke-activated pericytes and perivascular fibroblasts. Both populations of these cells remained segregated, displaying distinct angiogenic and fibrogenic profiles. Therefore, pericytes and perivascular fibroblasts are distinct subpopulations of SPCs in the adult brain that coordinate revascularization and scar formation after injury., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer Nature America, Inc.)- Published
- 2025
- Full Text
- View/download PDF
9. Nosemosis negatively affects honeybee survival: experimental and meta-analytic evidence.
- Author
-
Ostap-Chec M, Cait J, Scott RW, Arct A, Moroń D, Rapacz M, and Miler K
- Abstract
Nosemosis, caused by microsporidian parasites of the genus Nosema , is considered a significant health concern for insect pollinators, including the economically important honeybee ( Apis mellifera ). Despite its acknowledged importance, the impact of this disease on honeybee survivorship remains unclear. Here, a standard laboratory cage trial was used to compare mortality rates between healthy and Nosema -infected honeybees. Additionally, a systematic review and meta-analysis of existing literature were conducted to explore how nosemosis contributes to increased mortality in honeybees tested under standard conditions. The review and meta-analysis included 50 studies that reported relevant experiments involving healthy and Nosema -infected individuals. Studies lacking survivorship curves or information on potential moderators, such as spore inoculation dose, age of inoculated bees, or factors that may impact energy expenditure, were excluded. Both the experimental results and meta-analysis revealed a consistent, robust effect of infection, indicating a threefold increase in mortality among the infected group of honeybee workers (hazard ratio for infected individuals = 3.16 [1.97–5.07] and 2.99 [2.36–3.79] in the experiment and meta-analysis, respectively). However, the meta-analysis also indicated high heterogeneity in the effect magnitude, which was not explained by our moderators. Furthermore, there was a serious risk of bias within studies and potential publication bias across studies. The findings underscore knowledge gaps in the literature. It is stressed that laboratory cage trials should be viewed as an initial step in evaluating the impact of Nosema on mortality and that complementary field and apiary studies are essential for identifying effective treatments to preserve honeybee populations.
- Published
- 2024
- Full Text
- View/download PDF
10. Benchmarking bulk and single-cell variant-calling approaches on Chromium scRNA-seq and scATAC-seq libraries.
- Author
-
Wiens M, Farahani H, Scott RW, Underhill TM, and Bashashati A
- Subjects
- Humans, Chromium, Benchmarking, Gene Library, Sequence Analysis, RNA methods, RNA-Seq methods, High-Throughput Nucleotide Sequencing methods, Genetic Variation, Single-Cell Gene Expression Analysis, Single-Cell Analysis methods
- Abstract
Single-cell sequencing methodologies such as scRNA-seq and scATAC-seq have become widespread and effective tools to interrogate tissue composition. Increasingly, variant callers are being applied to these methodologies to resolve the genetic heterogeneity of a sample, especially in the case of detecting the clonal architecture of a tumor. Typically, traditional bulk DNA variant callers are applied to the pooled reads of a single-cell library to detect candidate mutations. Recently, multiple studies have applied such callers on reads from individual cells, with some citing the ability to detect rare variants with higher sensitivity. Many studies apply these two approaches to the Chromium (10x Genomics) scRNA-seq and scATAC-seq methodologies. However, Chromium-based libraries may offer additional challenges to variant calling compared with existing single-cell methodologies, raising questions regarding the validity of variants obtained from such a workflow. To determine the merits and challenges of various variant-calling approaches on Chromium scRNA-seq and scATAC-seq libraries, we use sample libraries with matched bulk whole-genome sequencing to evaluate the performance of callers. We review caller performance, finding that bulk callers applied on pooled reads significantly outperform individual-cell approaches. We also evaluate variants unique to scRNA-seq and scATAC-seq methodologies, finding patterns of noise but also potential capture of RNA-editing events. Finally, we review the notion that variant calling at the single-cell level can detect rare somatic variants, providing empirical results that suggest resolving such variants is infeasible in single-cell Chromium libraries., (© 2024 Wiens et al.; Published by Cold Spring Harbor Laboratory Press.)
- Published
- 2024
- Full Text
- View/download PDF
11. Potency of a small molecule that targets the molluscum contagiosum virus processivity factor increases when conjugated to a tripeptide.
- Author
-
Guan H, Nuth M, Scott RW, Parker MH, Strobel ED, Reitz AB, Kulp JL 3rd, and Ricciardi RP
- Subjects
- Humans, Virus Replication drug effects, Molluscum Contagiosum drug therapy, Oligopeptides pharmacology, Oligopeptides chemistry, Animals, Cell Line, Antiviral Agents pharmacology, Antiviral Agents chemistry, Antiviral Agents chemical synthesis, Molluscum contagiosum virus drug effects
- Abstract
We recently developed compound FC-7269 for targeting the Molluscum contagiosum virus processivity factor (mD4) and demonstrated its ability to inhibit viral processive DNA synthesis in vitro and cellular infection of an mD4-dependent virus (Antiviral Res 211, 2023,105520). However, despite a thorough medicinal chemistry campaign we were unable to generate a potent second analog as a requisite for drug development. We overcame this impasse, by conjugating a short hydrophobic trivaline peptide to FC-7269 to produce FC-TriVal-7269 which significantly increased antiviral potency and reduced cellular toxicity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)
- Published
- 2024
- Full Text
- View/download PDF
12. Single-cell analysis of mesenchymal cells in permeable neural vasculature reveals novel diverse subpopulations of fibroblasts.
- Author
-
Bastedo WE, Scott RW, Arostegui M, and Underhill TM
- Subjects
- Mice, Animals, Blood-Brain Barrier metabolism, Fibroblasts, Single-Cell Analysis, Choroid Plexus metabolism, Mesenchymal Stem Cells, Red Fluorescent Protein
- Abstract
Background: In the choroid plexus and pituitary gland, vasculature is known to have a permeable, fenestrated phenotype which allows for the free passage of molecules in contrast to the blood brain barrier observed in the rest of the CNS. The endothelium of these compartments, along with secretory, neural-lineage cells (choroid epithelium and pituitary endocrine cells) have been studied in detail, but less attention has been given to the perivascular mesenchymal cells of these compartments., Methods: The Hic1
CreERT2 Rosa26LSL-TdTomato mouse model was used in conjunction with a PdgfraH2B-EGFP mouse model to examine mesenchymal cells, which can be subdivided into Pdgfra+ fibroblasts and Pdgfra- pericytes within the choroid plexus (CP) and pituitary gland (PG), by histological, immunofluorescence staining and single-cell RNA-sequencing analyses., Results: We found that both CP and PG possess substantial populations of distinct Hic1+ mesenchymal cells, including an abundance of Pdgfra+ fibroblasts. Within the pituitary, we identified distinct subpopulations of Hic1+ fibroblasts in the glandular anterior pituitary and the neurosecretory posterior pituitary. We also identified multiple distinct markers of CP, PG, and the meningeal mesenchymal compartment, including alkaline phosphatase, indole-n-methyltransferase and CD34., Conclusions: Novel, distinct subpopulations of mesenchymal cells can be found in permeable vascular interfaces, including the CP, PG, and meninges, and make distinct contributions to both organs through the production of structural proteins, enzymes, transporters, and trophic molecules., (© 2024. The Author(s).)- Published
- 2024
- Full Text
- View/download PDF
13. Epichloë fungal endophyte interactions in perennial ryegrass (Lolium perenne L.) modified to accumulate foliar lipids for increased energy density.
- Author
-
Richardson KA, de Bonth ACM, Beechey-Gradwell Z, Kadam S, Cooney LJ, Nelson KA, Cookson R, Winichayakul S, Reid M, Anderson P, Crowther T, Zou X, Maher D, Xue H, Scott RW, Allan A, Johnson RD, Card SD, Mace WJ, Roberts NJ, and Bryan G
- Subjects
- Endophytes metabolism, Symbiosis, Poaceae metabolism, Lipids, Lolium genetics, Epichloe genetics, Epichloe metabolism, Alkaloids metabolism
- Abstract
Background: Commercial cultivars of perennial ryegrass infected with selected Epichloë fungal endophytes are highly desirable in certain pastures as the resulting mutualistic association has the capacity to confer agronomic benefits (such as invertebrate pest deterrence) largely due to fungal produced secondary metabolites (e.g., alkaloids). In this study, we investigated T
2 segregating populations derived from two independent transformation events expressing diacylglycerol acyltransferase (DGAT) and cysteine oleosin (CO) genes designed to increase foliar lipid and biomass accumulation. These populations were either infected with Epichloë festucae var. lolii strain AR1 or Epichloë sp. LpTG-3 strain AR37 to examine relationships between the introduced trait and the endophytic association. Here we report on experiments designed to investigate if expression of the DGAT + CO trait in foliar tissues of perennial ryegrass could negatively impact the grass-endophyte association and vice versa. Both endophyte and plant characters were measured under controlled environment and field conditions., Results: Expected relative increases in total fatty acids of 17-58% accrued as a result of DGAT + CO expression with no significant difference between the endophyte-infected and non-infected progeny. Hyphal growth in association with DGAT + CO expression appeared normal when compared to control plants in a growth chamber. There was no significant difference in mycelial biomass for both strains AR1 and AR37, however, Epichloë-derived alkaloid concentrations were significantly lower on some occasions in the DGAT + CO plants compared to the corresponding null-segregant progenies, although these remained within the reported range for bioactivity., Conclusions: These results suggest that the mutualistic association formed between perennial ryegrass and selected Epichloë strains does not influence expression of the host DGAT + CO technology, but that endophyte performance may be reduced under some circumstances. Further investigation will now be required to determine the preferred genetic backgrounds for introgression of the DGAT + CO trait in combination with selected endophyte strains, as grass host genetics is a major determinant to the success of the grass-endophyte association in this species., (© 2023. The Author(s).)- Published
- 2023
- Full Text
- View/download PDF
14. Time-series transcriptomic profiling of larval exsheathment in a model parasitic nematode of veterinary importance.
- Author
-
Palevich N, Maclean PH, and Scott RW
- Abstract
Competing Interests: Authors NP, PM and RS were employed by AgResearch Limited. The reviewer IM declared a past co-authorship with the author NP to the handling editor.
- Published
- 2023
- Full Text
- View/download PDF
15. Aberrant gene activation in synovial sarcoma relies on SSX specificity and increased PRC1.1 stability.
- Author
-
Benabdallah NS, Dalal V, Scott RW, Marcous F, Sotiriou A, Kommoss FKF, Pejkovska A, Gaspar L, Wagner L, Sánchez-Rivera FJ, Ta M, Thornton S, Nielsen TO, Underhill TM, and Banito A
- Subjects
- Humans, Animals, Mice, Polycomb Repressive Complex 1 genetics, Transcriptional Activation, Cell Nucleus metabolism, Chromatin metabolism, Oncogene Proteins, Fusion metabolism, Cell Cycle Proteins metabolism, Sarcoma, Synovial genetics, Sarcoma, Synovial metabolism
- Abstract
The SS18-SSX fusion drives oncogenic transformation in synovial sarcoma by bridging SS18, a member of the mSWI/SNF (BAF) complex, to Polycomb repressive complex 1 (PRC1) target genes. Here we show that the ability of SS18-SSX to occupy H2AK119ub1-rich regions is an intrinsic property of its SSX C terminus, which can be exploited by fusion to transcriptional regulators beyond SS18. Accordingly, SS18-SSX recruitment occurs in a manner that is independent of the core components and catalytic activity of BAF. Alternative SSX fusions are also recruited to H2AK119ub1-rich chromatin and reproduce the expression signatures of SS18-SSX by engaging with transcriptional activators. Variant Polycomb repressive complex 1.1 (PRC1.1) acts as the main depositor of H2AK119ub1 and is therefore required for SS18-SSX occupancy. Importantly, the SSX C terminus not only depends on H2AK119ub1 for localization, but also further increases it by promoting PRC1.1 complex stability. Consequently, high H2AK119ub1 levels are a feature of murine and human synovial sarcomas. These results uncover a critical role for SSX-C in mediating gene deregulation in synovial sarcoma by providing specificity to chromatin and further enabling oncofusion binding by enhancing PRC1.1 stability and H2AK119ub1 deposition., (© 2023. The Author(s).)
- Published
- 2023
- Full Text
- View/download PDF
16. Amide- and bis-amide-linked highly potent and broadly active antifungal agents for the treatment of invasive fungal infections- towards the discovery of pre-clinical development candidate FC12406.
- Author
-
Baugh SDP, Chaly A, Weaver DG, Whitman DB, Pelletier JC, Bian H, Freeman KB, Reitz AB, and Scott RW
- Abstract
Most fungal infections are common, localized to skin or mucosal surfaces and can be treated effectively with topical antifungal agents. However, while invasive fungal infections (IFIs) are uncommon, they are very difficult to control medically, and are associated with high mortality rates. We have previously described highly potent bis-guanidine-containing heteroaryl-linked antifungal agents, and were interested in expanding the range of agents to novel series so as to reduce the degree of aromaticity (with a view to making the compounds more drug-like), and provide broadly active high potency derivatives. We have investigated the replacement of the central aryl ring from our original series by both amide and a bis-amide moieties, and have found particular structure-activity relationships (SAR) for both series', resulting in highly active antifungal agents against both mold and yeast pathogens. In particular, we describe the in vitro antifungal activity, absorption, distribution, metabolism and elimination (ADME) properties, and off-target properties of FC12406 (34), which was selected as a pre-clinical development candidate., Competing Interests: Conflict of interestThe authors declare no competing interests., (© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)
- Published
- 2023
- Full Text
- View/download PDF
17. Hic1 identifies a specialized mesenchymal progenitor population in the embryonic limb responsible for bone superstructure formation.
- Author
-
Arostegui M, Scott RW, and Underhill TM
- Subjects
- Osteogenesis, Bone and Bones, Cartilage, Tendons, Muscle, Skeletal
- Abstract
The musculoskeletal system relies on the integration of multiple components with diverse physical properties, such as striated muscle, tendon, and bone, that enable locomotion and structural stability. This relies on the emergence of specialized, but poorly characterized, interfaces between these various elements during embryonic development. Within the appendicular skeleton, we show that a subset of mesenchymal progenitors (MPs), identified by Hic1, do not contribute to the primary cartilaginous anlagen but represent the MP population, whose progeny directly contribute to the interfaces that connect bone to tendon (entheses), tendon to muscle (myotendinous junctions), and the associated superstructures. Furthermore, deletion of Hic1 leads to skeletal defects reflective of deficient muscle-bone coupling and, consequently, perturbation of ambulation. Collectively, these findings show that Hic1 identifies a unique MP population that contributes to a secondary wave of bone sculpting critical to skeletal morphogenesis., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
18. A small molecule that targets the processivity factor of molluscum contagiosum virus has therapeutic potential.
- Author
-
Guan H, Nuth M, Isaacs SN, Xiao Y, Scott RW, Parker MH, Strobel ED, Kulp JL 3rd, Bailey TR, Reitz AB, and Ricciardi RP
- Subjects
- Child, Humans, Viral Proteins genetics, DNA metabolism, Molluscum contagiosum virus genetics, Molluscum contagiosum virus metabolism, Molluscum Contagiosum
- Abstract
Molluscum contagiosum (MC) is an infectious disease that occurs only in humans with a tropism that is narrowly restricted to the outermost epidermal layer of the skin. Molluscum contagiosum virus (MCV) is the causative agent of MC which produces skin lesions that can persist for months to several years. MCV is efficiently transmitted by direct physical contact or by indirect contact with fomites. MC is most prevalent in children and immune compromised patients. The failure to develop a drug that targets MCV replication has been hampered for decades by the inability to propagate MCV in cell culture. To address this dilemma, we recently engineered a surrogate poxvirus expressing the MCV processivity factor (mD4) as the drug target. The mD4 protein is essential for viral replication by keeping the viral polymerase tethered to the DNA template. In this study we have designed and synthesized a lead compound (7269) that is able to prevent mD4 dependent processive DNA synthesis in vitro (IC
50 = 6.8 μM) and effectively inhibit propagation of the mD4-VV surrogate virus in BSC-1 cells (EC50 = 13.2 μM) with negligible cytotoxicity. In human liver microsomes, 7269 was shown to be stable for almost 2 h. When tested for penetration into human cadaver skin in a formulated gel, the level of 7269 in the epidermal layer was nearly 100 times the concentration (EC50 ) needed to inhibit propagation of the mD4-VV surrogate virus in BSC-1 cells. The gel formulated 7269 was scored as a non-irritant on skin and shown to have a shelf-life that was completely stable after several months. In summary, 7269 is a potential Lead for becoming the first MCV anti-viral compound to treat MC and thereby, addresses this unmet medical need that has persisted for many decades., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)- Published
- 2023
- Full Text
- View/download PDF
19. Extracurricular work experience and its association with training and confidence in emergency medicine procedures among medical students: a cross-sectional study from a Norwegian medical school.
- Author
-
Scott RW and Fredriksen K
- Subjects
- Cross-Sectional Studies, Humans, Schools, Medical, Surveys and Questionnaires, Education, Medical, Undergraduate, Emergency Medicine, Students, Medical
- Abstract
Objective: Proficiency in basic emergency procedures is important for junior doctors, but the amount of practical exposure may vary. We studied the association between students' extracurricular healthcare-related (ECHR) work experience and self-reported practical training and confidence in selected emergency medicine procedures., Study Design: Cross-sectional study., Materials and Methods: Medical students and first-year graduates answered a Likert-based questionnaire probing self-reported amount of exposure to ('training amount') and confidence with selected emergency medicine procedures. Participants also reported ECHR work experience, year of study, previous healthcare-related education, military medic training and participation in the local student association for emergency medicine (Tromsø Acute Medicine Students' Association (TAMS)). Differences within variables were analysed with independent samples t-tests, and correlation between training amount and confidence was calculated. Analysis of covariance and mixed models were applied to study associations between training amount and confidence, and work experience (primary outcomes) and the other reported factors (secondary outcomes), respectively., Results: 539 participants responded (70%). Among these, 81% had ECHR work experience. There was a strong correlation (r=0.878) between training amount and confidence. Work experience accounted for 5.9% and 3.5% of the total variance in training amount and confidence (primary outcomes), and respondents with work experience scored significantly higher than respondents without work experience. Year of study, previous education, military medic training and TAMS participation accounted for 49.3%, 8.7%, 6.8% and 23.6%, and 58.5%, 5.1%, 4.7% and 12.3% of the total variance in training amount and confidence, respectively (secondary outcomes). Cohen's D was 0.48 for training amount and 0.32 for confidence level, suggesting medium and weak medium-sized associations with work experience, respectively., Conclusion: ECHR work experience is common among medical students and was associated with more training amount and higher confidence in the procedures. Year of study, previous relevant education and TAMS participation, but not military medic training, were also significantly associated with training amount and confidence., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2022
- Full Text
- View/download PDF
20. Cellular taxonomy of Hic1 + mesenchymal progenitor derivatives in the limb: from embryo to adult.
- Author
-
Arostegui M, Scott RW, Böse K, and Underhill TM
- Subjects
- Cell Differentiation, Embryo, Mammalian, Extremities, Limb Buds, Mesenchymal Stem Cells
- Abstract
Tissue development and regeneration rely on the cooperation of multiple mesenchymal progenitor (MP) subpopulations. We recently identified Hic1 as a marker of quiescent MPs in multiple adult tissues. Here, we describe the embryonic origin of appendicular Hic1
+ MPs and demonstrate that they arise in the hypaxial somite, and migrate into the developing limb at embryonic day 11.5, well after limb bud initiation. Time-resolved single-cell-omics analyses coupled with lineage tracing reveal that Hic1+ cells generate a unique MP hierarchy, that includes both recently identified adult universal fibroblast populations (Dpt+ , Pi16+ and Dpt+ Col15a1+ ) and more specialised mesenchymal derivatives such as, peri and endoneurial cells, pericytes, bone marrow stromal cells, myotenocytes, tenocytes, fascia-resident fibroblasts, with limited contributions to chondrocytes and osteocytes within the skeletal elements. MPs endure within these compartments, continue to express Hic1 and represent a critical reservoir to support post-natal growth and regeneration., (© 2022. The Author(s).)- Published
- 2022
- Full Text
- View/download PDF
21. Barriers to body temperature monitoring among prehospital personnel: a qualitative study using the modified nominal group technique.
- Author
-
Scott RW and Fredriksen K
- Subjects
- Consensus, Humans, Norway, Qualitative Research, Body Temperature, Emergency Medical Services methods
- Abstract
Objectives: To identify and explore barriers that healthcare professionals working as prehospital care (PHC) providers at the University Hospital of North Norway experience with temperature monitoring and discover solutions to these problems., Study Design: Qualitative study using the modified nominal group technique., Materials and Methods: 14 experienced healthcare professionals working in air and ground emergency medical services were invited to the study. Initially, each participant was asked to suggest through email topics of importance regarding barriers to prehospital thermometry. Afterwards, they received a list of all disparate topics and were asked to individually rank them by importance. The top-ranked topics were discussed in a consensus meeting. The meeting was audio-recorded and a transcript was written and then analysed through an inductive thematic analysis., Results: 13 participants accepted the invitation. 63 suggestions were reduced to 24 disparate topics after removal of duplicates. Twelve highly ranked topics were discussed during the consensus meeting. Thematic analysis revealed 47 codes that were grouped together into six overarching themes, of which four described challenges to monitoring and two described potential solutions: equipment dissatisfaction, little focus on patient temperature, fear of iatrogenic complications, thermometry subordinated, more focus on temperature and simplification of thermometry., Conclusion: To increase the frequency of temperature measurement on correct indication, we suggest introducing PHC protocols that specify patients and conditions where an accurate temperature measurement should have high priority. Furthermore, there is a profound need for more suitable techniques for temperature monitoring in the prehospital setting., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2022
- Full Text
- View/download PDF
22. Conventional laboratory housing increases morbidity and mortality in research rodents: results of a meta-analysis.
- Author
-
Cait J, Cait A, Scott RW, Winder CB, and Mason GJ
- Subjects
- Animals, Female, Housing, Male, Mice, Morbidity, Rats, Rodentia, Cardiovascular Diseases, Neoplasms, Stroke
- Abstract
Background: Over 120 million mice and rats are used annually in research, conventionally housed in shoebox-sized cages that restrict natural behaviours (e.g. nesting and burrowing). This can reduce physical fitness, impair thermoregulation and reduce welfare (e.g. inducing abnormal stereotypic behaviours). In humans, chronic stress has biological costs, increasing disease risks and potentially shortening life. Using a pre-registered protocol ( https://atrium.lib.uoguelph.ca/xmlui/handle/10214/17955 ), this meta-analysis therefore tested the hypothesis that, compared to rodents in 'enriched' housing that better meets their needs, conventional housing increases stress-related morbidity and all-cause mortality., Results: Comprehensive searches (via Ovid, CABI, Web of Science, Proquest and SCOPUS on May 24 2020) yielded 10,094 publications. Screening for inclusion criteria (published in English, using mice or rats and providing 'enrichments' in long-term housing) yielded 214 studies (within 165 articles, using 6495 animals: 59.1% mice; 68.2% male; 31.8% isolation-housed), and data on all-cause mortality plus five experimentally induced stress-sensitive diseases: anxiety, cancer, cardiovascular disease, depression and stroke. The Systematic Review Center for Laboratory animal Experimentation (SYRCLE) tool assessed individual studies' risks of bias. Random-effects meta-analyses supported the hypothesis: conventional housing significantly exacerbated disease severity with medium to large effect sizes: cancer (SMD = 0.71, 95% CI = 0.54-0.88); cardiovascular disease (SMD = 0.72, 95% CI = 0.35-1.09); stroke (SMD = 0.87, 95% CI = 0.59-1.15); signs of anxiety (SMD = 0.91, 95% CI = 0.56-1.25); signs of depression (SMD = 1.24, 95% CI = 0.98-1.49). It also increased mortality rates (hazard ratio = 1.48, 95% CI = 1.25-1.74; relative median survival = 0.91, 95% CI = 0.89-0.94). Meta-regressions indicated that such housing effects were ubiquitous across species and sexes, but could not identify the most impactful improvements to conventional housing. Data variability (assessed via coefficient of variation) was also not increased by 'enriched' housing., Conclusions: Conventional housing appears sufficiently distressing to compromise rodent health, raising ethical concerns. Results also add to previous work to show that research rodents are typically CRAMPED (cold, rotund, abnormal, male-biased, poorly surviving, enclosed and distressed), raising questions about the validity and generalisability of the data they generate. This research was funded by NSERC, Canada., (© 2022. The Author(s).)
- Published
- 2022
- Full Text
- View/download PDF
23. Effects of ultraviolet-filters on Daphnia magna development and endocrine-related gene expression.
- Author
-
Lambert FN, Gracy HR, Gracy AJ, Yoon SH, Scott RW, Rincon DM, and Vulpe CD
- Abstract
Ultraviolet (UV) filters are emerging contaminants of concern that are widely spread throughout the aquatic environment. Many organic UV filters are endocrine disrupting compounds (EDCs) in vertebrates. However, few studies have assessed their effects on invertebrates. Molting, or the shedding of the exoskeleton, may be affected by exposure to these compounds in Arthropods (the largest phylum of invertebrates). Molting is necessary for growth and development and is regulated by an arthropod specific endocrine system, the ecdysteroid pathway. Alterations of this process by EDCs can result in improper development, reduced growth, and even death. We investigated the sublethal effects of chronic exposure to three organic UV filters (4-methylbenzylidene camphor (4MBC), octylmethoxycinnamate (OMC), and benzophenone-3 (BP3) in a crustacean, Daphnia magna, with particular emphasis on molting and development. We demonstrate that 4MBC, OMC, and BP3 affect development and long-term health in neonates of exposed parents at concentrations of 130 µg/L, 75 µg/L, and 166 µg/L, respectively. Additionally, the expression of endocrine-related genes (including ultraspiracle protein, usp) are significantly altered by 4MBC and BP3 exposure, which may relate to their developmental toxicity., (Copyright © 2021. Published by Elsevier B.V.)
- Published
- 2021
- Full Text
- View/download PDF
24. Changes in Leaf-Level Nitrogen Partitioning and Mesophyll Conductance Deliver Increased Photosynthesis for Lolium perenne Leaves Engineered to Accumulate Lipid Carbon Sinks.
- Author
-
Cooney LJ, Beechey-Gradwell Z, Winichayakul S, Richardson KA, Crowther T, Anderson P, Scott RW, Bryan G, and Roberts NJ
- Abstract
Diacylglycerol acyl-transferase (DGAT) and cysteine oleosin (CO) expression confers a novel carbon sink (of encapsulated lipid droplets) in leaves of Lolium perenne and has been shown to increase photosynthesis and biomass. However, the physiological mechanism by which DGAT + CO increases photosynthesis remains unresolved. To evaluate the relationship between sink strength and photosynthesis, we examined fatty acids (FA), water-soluble carbohydrates (WSC), gas exchange parameters and leaf nitrogen for multiple DGAT + CO lines varying in transgene accumulation. To identify the physiological traits which deliver increased photosynthesis, we assessed two important determinants of photosynthetic efficiency, CO
2 conductance from atmosphere to chloroplast, and nitrogen partitioning between different photosynthetic and non-photosynthetic pools. We found that DGAT + CO accumulation increased FA at the expense of WSC in leaves of L. perenne and for those lines with a significant reduction in WSC, we also observed an increase in photosynthesis and photosynthetic nitrogen use efficiency. DGAT + CO L. perenne displayed no change in rubisco content or Vcmax but did exhibit a significant increase in specific leaf area (SLA), stomatal and mesophyll conductance, and leaf nitrogen allocated to photosynthetic electron transport. Collectively, we showed that increased carbon demand via DGAT+CO lipid sink accumulation can induce leaf-level changes in L. perenne which deliver increased rates of photosynthesis and growth. Carbon sinks engineered within photosynthetic cells provide a promising new strategy for increasing photosynthesis and crop productivity., Competing Interests: The DGAT+CO ryegrass material examined in this study was generated with funding from DairyNZ, PGG Wrightson Seeds and Grasslanz Technology. The research conducted here, including all experimental designs and analyses was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Cooney, Beechey-Gradwell, Winichayakul, Richardson, Crowther, Anderson, Scott, Bryan and Roberts.)- Published
- 2021
- Full Text
- View/download PDF
25. Distinct Regulatory Programs Control the Latent Regenerative Potential of Dermal Fibroblasts during Wound Healing.
- Author
-
Abbasi S, Sinha S, Labit E, Rosin NL, Yoon G, Rahmani W, Jaffer A, Sharma N, Hagner A, Shah P, Arora R, Yoon J, Islam A, Uchida A, Chang CK, Stratton JA, Scott RW, Rossi FMV, Underhill TM, and Biernaskie J
- Published
- 2021
- Full Text
- View/download PDF
26. Highly potent, broadly active antifungal agents for the treatment of invasive fungal infections.
- Author
-
Baugh SDP, Chaly A, Weaver DG, Pelletier JC, Thanna S, Freeman KB, Reitz AB, and Scott RW
- Subjects
- Antifungal Agents chemical synthesis, Antifungal Agents chemistry, Aspergillus drug effects, Candida drug effects, Dose-Response Relationship, Drug, Guanidine analogs & derivatives, Guanidine chemistry, Microbial Sensitivity Tests, Molecular Structure, Structure-Activity Relationship, Antifungal Agents pharmacology, Guanidine pharmacology, Invasive Fungal Infections drug therapy
- Abstract
Invasive fungal infections have become an important healthcare issue due in large part to high mortality rates under standard of care (SOC) therapies creating an urgent need for new and effective anti-fungal agents. We have developed a series of non-peptide, structurally-constrained analogs of host defence proteins that have distinct advantages over peptides for pharmaceutical uses. Here we report the chemical optimization of bis-guanidine analogs focused on alterations of the central aryl core and the connection of it to the terminal guanidines. This effort resulted in the production of highly potent, broadly active compounds with low mammalian cell cytotoxicity that have comparable or improved antifungal activities over SOC agents. One optimal compound was also found to possess favourable in vitro pharmaceutical and off-target properties suitable for further development., (Copyright © 2020 Elsevier Ltd. All rights reserved.)
- Published
- 2021
- Full Text
- View/download PDF
27. Herpes Simplex Virus-1 infection in human primary corneal epithelial cells is blocked by a stapled peptide that targets processive DNA synthesis.
- Author
-
Guan H, Nuth M, Lee V, Lin C, Mitchell CH, Lu W, Scott RW, Parker MH, Kulp JL 3rd, Reitz AB, and Ricciardi RP
- Subjects
- DNA, Epithelial Cells, Humans, Peptides pharmacology, Herpesvirus 1, Human genetics, Keratitis, Herpetic drug therapy
- Abstract
Purpose: Acyclovir is most commonly used for treating ocular Herpes Keratitis, a leading cause of infectious blindness. However, emerging resistance to Acyclovir resulting from mutations in the thymidine kinase gene of Herpes Simplex Virus -1 (HSV-1), has prompted the need for new therapeutics directed against a different viral protein. One novel target is the HSV-1 Processivity Factor which is essential for tethering HSV-1 Polymerase to the viral genome to enable long-chain DNA synthesis., Methods: A series of peptides, based on the crystal structure of the C-terminus of HSV-1 Polymerase, were constructed with hydrocarbon staples to retain their alpha-helical conformation. The stapled peptides were tested for blocking both HSV-1 DNA synthesis and infection. The most effective peptide was further optimized by replacing its negative N-terminus with two hydrophobic valine residues. This di-valine stapled peptide was tested for inhibiting HSV-1 infection of human primary corneal epithelial cells., Results: The stapled peptides blocked HSV-1 DNA synthesis and HSV-1 infection. The unstapled control peptide had no inhibitory effects. Specificity of the stapled peptides was confirmed by their inabilities to block infection by an unrelated virus. Significantly, the optimized di-valine stapled peptide effectively blocked HSV-1 infection in human primary corneal epithelial cells with selectivity index of 11.6., Conclusions: Hydrocarbon stapled peptides that simulate the α-helix from the C-terminus of HSV-1 DNA polymerase can specifically block DNA synthesis and infection of HSV-1 in human primary corneal epithelial cells. These stapled peptides provide a foundation for developing a topical therapeutic for treating human ocular Herpes Keratitis., (Copyright © 2020. Published by Elsevier Inc.)
- Published
- 2021
- Full Text
- View/download PDF
28. Abortive γδTCR rearrangements suggest ILC2s are derived from T-cell precursors.
- Author
-
Shin SB, Lo BC, Ghaedi M, Scott RW, Li Y, Messing M, Hernaez DC, Cait J, Murakami T, Hughes MR, Leslie KB, Underhill TM, Takei F, and McNagny KM
- Subjects
- Leukocytes, Lymphocytes, Immunity, Innate, Precursor Cells, T-Lymphoid
- Abstract
Innate lymphoid cells (ILCs) are a recently identified subset of leukocytes that play a central role in pathogen surveillance and resistance, modulation of immune response, and tissue repair. They are remarkably similar to CD4+ T-helper subsets in terms of function and transcription factors required for their development but are distinguished by their lack of antigen-specific receptors. Despite their similarities, the absence of a surface T-cell receptor (TCR) and presence of ILCs and precursors in adult bone marrow has led to speculation that ILCs and T cells develop separately from lineages that branch at the point of precursors within the bone marrow. Considering the common lineage markers and effector cytokine profiles shared between ILCs and T cells, it is surprising that the status of the TCR loci in ILCs was not fully explored at the time of their discovery. Here, we demonstrate that a high proportion of peripheral tissue ILC2s have TCRγ chain gene rearrangements and TCRδ locus deletions. Detailed analyses of these loci show abundant frameshifts and premature stop codons that would encode nonfunctional TCR proteins. Collectively, these data argue that ILC2 can develop from T cells that fail to appropriately rearrange TCR genes, potentially within the thymus., (© 2020 by The American Society of Hematology.)
- Published
- 2020
- Full Text
- View/download PDF
29. A Novel Immunocompetent Mouse Model for Testing Antifungal Drugs Against Invasive Candida albicans Infection.
- Author
-
Ryan LK, Hise AG, Hossain CM, Ruddick W, Parveen R, Freeman KB, Weaver DG, Narra HP, Scott RW, and Diamond G
- Abstract
Disseminated infection by Candida species represents a common, often life-threatening condition. Increased resistance to current antifungal drugs has led to an urgent need to develop new antifungal drugs to treat this pathogen. However, in vivo screening of candidate antifungal compounds requires large numbers of animals and using immunosuppressive agents to allow for fungal dissemination. To increase the efficiency of screening, to use fewer mice, and to remove the need for immunosuppressive agents, which may interfere with the drug candidates, we tested the potential for a novel approach using in vivo imaging of a fluorescent strain of Candida albicans , in a mouse strain deficient in the host defense peptide, murine β-defensin 1 (mBD-1). We developed a strain of C. albicans that expresses red fluorescent protein (RFP), which exhibits similar infectivity to the non-fluorescent parent strain. When this strain was injected into immunocompetent mBD-1-deficient mice, we observed a non-lethal disseminated infection. Further, we could quantify its dissemination in real time, and observe the activity of an antifungal peptide mimetic drug by in vivo imaging. This novel method will allow for the rapid in vivo screening of antifungal drugs, using fewer mice, and increase the efficiency of testing new antifungal agents.
- Published
- 2020
- Full Text
- View/download PDF
30. Distinct Regulatory Programs Control the Latent Regenerative Potential of Dermal Fibroblasts during Wound Healing.
- Author
-
Abbasi S, Sinha S, Labit E, Rosin NL, Yoon G, Rahmani W, Jaffer A, Sharma N, Hagner A, Shah P, Arora R, Yoon J, Islam A, Uchida A, Chang CK, Stratton JA, Scott RW, Rossi FMV, Underhill TM, and Biernaskie J
- Subjects
- Cicatrix pathology, Fibroblasts, Hair Follicle, Humans, Skin, Dermis pathology, Wound Healing
- Abstract
Dermal fibroblasts exhibit considerable heterogeneity during homeostasis and in response to injury. Defining lineage origins of reparative fibroblasts and regulatory programs that drive fibrosis or, conversely, promote regeneration will be essential for improving healing outcomes. Using complementary fate-mapping approaches, we show that hair follicle mesenchymal progenitors make limited contributions to wound repair. In contrast, extrafollicular progenitors marked by the quiescence-associated factor Hic1 generated the bulk of reparative fibroblasts and exhibited functional divergence, mediating regeneration in the center of the wound neodermis and scar formation in the periphery. Single-cell RNA-seq revealed unique transcriptional, regulatory, and epithelial-mesenchymal crosstalk signatures that enabled mesenchymal competence for regeneration. Integration with scATAC-seq highlighted changes in chromatin accessibility within regeneration-associated loci. Finally, pharmacological modulation of RUNX1 and retinoic acid signaling or genetic deletion of Hic1 within wound-activated fibroblasts was sufficient to modulate healing outcomes, suggesting that reparative fibroblasts have latent but modifiable regenerative capacity., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 Elsevier Inc. All rights reserved.)
- Published
- 2020
- Full Text
- View/download PDF
31. Development and function of smooth muscle cells is modulated by Hic1 in mouse testis.
- Author
-
Uchida A, Sakib S, Labit E, Abbasi S, Scott RW, Underhill TM, Biernaskie J, and Dobrinski I
- Subjects
- Actins genetics, Actins metabolism, Animals, Fibronectins genetics, Kruppel-Like Transcription Factors genetics, Kruppel-Like Transcription Factors metabolism, Male, Microfilament Proteins genetics, Microfilament Proteins metabolism, Fibronectins metabolism, Myocytes, Smooth Muscle metabolism, Testis metabolism
- Abstract
In mammalian testis, contractile peritubular myoid cells (PMCs) regulate the transport of sperm and luminal fluid, while secreting growth factors and extracellular matrix proteins to support the spermatogonial stem cell niche. However, little is known about the role of testicular smooth muscle cells during postnatal testicular development. Here we report age-dependent expression of hypermethylated in cancer 1 ( Hic1 ; also known as ZBTB29 ) in testicular smooth muscle cells, including PMCs and vascular smooth muscle cells, in the mouse. Postnatal deletion of Hic1 in smooth muscle cells led to their increased proliferation and resulted in dilatation of seminiferous tubules, with increased numbers of PMCs. These seminiferous tubules contained fewer Sertoli cells and more spermatogonia, and fibronectin was not detected in their basement membrane. The expression levels of genes encoding smooth muscle contractile proteins, Acta2 and Cnn1 , were downregulated in the smooth muscle cells lacking Hic1 , and the seminiferous tubules appeared to have reduced contractility. These data imply a role for Hic1 in determining the size of seminiferous tubules by regulating postnatal smooth muscle cell proliferation, subsequently affecting spermatogenesis in adulthood., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2020. Published by The Company of Biologists Ltd.)
- Published
- 2020
- Full Text
- View/download PDF
32. Pathogenic Potential of Hic1-Expressing Cardiac Stromal Progenitors.
- Author
-
Soliman H, Paylor B, Scott RW, Lemos DR, Chang C, Arostegui M, Low M, Lee C, Fiore D, Braghetta P, Pospichalova V, Barkauskas CE, Korinek V, Rampazzo A, MacLeod K, Underhill TM, and Rossi FMV
- Published
- 2020
- Full Text
- View/download PDF
33. The Transcription Factor RORα Preserves ILC3 Lineage Identity and Function during Chronic Intestinal Infection.
- Author
-
Lo BC, Canals Hernaez D, Scott RW, Hughes MR, Shin SB, Underhill TM, Takei F, and McNagny KM
- Subjects
- Animals, Biomarkers, Chronic Disease, Disease Models, Animal, Enteritis pathology, Fibrosis, Lymphoid Tissue immunology, Lymphoid Tissue metabolism, Mice, Enteritis etiology, Enteritis metabolism, Immunity, Innate, Lymphocytes immunology, Lymphocytes metabolism, Nuclear Receptor Subfamily 1, Group F, Member 1 metabolism
- Abstract
Innate lymphoid cells (ILCs) are critical for host defense and tissue repair but can also contribute to chronic inflammatory diseases. The transcription factor RORα is required for ILC2 development but is also highly expressed by other ILC subsets where its function remains poorly defined. We previously reported that Rora
sg/sg bone marrow chimeric mice (C57BL/6J) were protected from Salmonella -induced intestinal fibrosis due to defective ILC3 responses. In this study, single-cell RNA analysis of ILCs isolated from inflamed tissues indicates that RORα perturbation led to a reduction in ILC3 lineages. Furthermore, residual Rorasg/sg ILC3s have decreased expression of key signature genes, including Rorc and activating cytokine receptors. Collectively, our data suggest that RORα plays a key role in preserving functional ILC3s by modulating their ability to integrate environmental cues to efficiently produce cytokines., (Copyright © 2019 by The American Association of Immunologists, Inc.)- Published
- 2019
- Full Text
- View/download PDF
34. Hic1 Defines Quiescent Mesenchymal Progenitor Subpopulations with Distinct Functions and Fates in Skeletal Muscle Regeneration.
- Author
-
Scott RW, Arostegui M, Schweitzer R, Rossi FMV, and Underhill TM
- Subjects
- Animals, Cell Cycle genetics, Cell Cycle physiology, Cell Differentiation genetics, Cell Differentiation physiology, Cell Proliferation genetics, Cell Proliferation physiology, Cells, Cultured, Female, Fluorescent Antibody Technique, Kruppel-Like Transcription Factors genetics, Male, Mice, Regeneration genetics, Wound Healing genetics, Wound Healing physiology, Kruppel-Like Transcription Factors metabolism, Muscle, Skeletal metabolism, Muscle, Skeletal physiology, Regeneration physiology, Satellite Cells, Skeletal Muscle metabolism
- Abstract
Many adult tissues contain resident stem cells, such as the Pax7
+ satellite cells within skeletal muscle, that regenerate parenchymal elements following damage. Tissue-resident mesenchymal progenitors (MPs) also participate in regeneration, although their function and fate in this process are unclear. Here, we identify Hypermethylated in cancer 1 (Hic1) as a marker of MPs in skeletal muscle and further show that Hic1 deletion leads to MP hyperplasia. Single-cell RNA-seq and ATAC-seq analysis of Hic1+ MPs in skeletal muscle shows multiple subpopulations, which we further show have distinct functions and lineage potential. Hic1+ MPs orchestrate multiple aspects of skeletal muscle regeneration by providing stage-specific immunomodulation and trophic and mechanical support. During muscle regeneration, Hic1+ derivatives directly contribute to several mesenchymal compartments including Col22a1-expressing cells within the myotendinous junction. Collectively, these findings demonstrate that HIC1 regulates MP quiescence and identifies MP subpopulations with transient and enduring roles in muscle regeneration., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2019
- Full Text
- View/download PDF
35. Clonal Decomposition and DNA Replication States Defined by Scaled Single-Cell Genome Sequencing.
- Author
-
Laks E, McPherson A, Zahn H, Lai D, Steif A, Brimhall J, Biele J, Wang B, Masud T, Ting J, Grewal D, Nielsen C, Leung S, Bojilova V, Smith M, Golovko O, Poon S, Eirew P, Kabeer F, Ruiz de Algara T, Lee SR, Taghiyar MJ, Huebner C, Ngo J, Chan T, Vatrt-Watts S, Walters P, Abrar N, Chan S, Wiens M, Martin L, Scott RW, Underhill TM, Chavez E, Steidl C, Da Costa D, Ma Y, Coope RJN, Corbett R, Pleasance S, Moore R, Mungall AJ, Mar C, Cafferty F, Gelmon K, Chia S, Marra MA, Hansen C, Shah SP, and Aparicio S
- Subjects
- Aneuploidy, Animals, Cell Cycle genetics, Cell Line, Tumor, Cell Shape, Cell Survival, Chromosomes, Human genetics, Clone Cells, DNA Transposable Elements genetics, Diploidy, Female, Genotype, Humans, Male, Mice, Mutation genetics, Phylogeny, Polymorphism, Single Nucleotide genetics, DNA Replication genetics, Genome, Human, High-Throughput Nucleotide Sequencing, Single-Cell Analysis
- Abstract
Accurate measurement of clonal genotypes, mutational processes, and replication states from individual tumor-cell genomes will facilitate improved understanding of tumor evolution. We have developed DLP+, a scalable single-cell whole-genome sequencing platform implemented using commodity instruments, image-based object recognition, and open source computational methods. Using DLP+, we have generated a resource of 51,926 single-cell genomes and matched cell images from diverse cell types including cell lines, xenografts, and diagnostic samples with limited material. From this resource we have defined variation in mitotic mis-segregation rates across tissue types and genotypes. Analysis of matched genomic and image measurements revealed correlations between cellular morphology and genome ploidy states. Aggregation of cells sharing copy number profiles allowed for calculation of single-nucleotide resolution clonal genotypes and inference of clonal phylogenies and avoided the limitations of bulk deconvolution. Finally, joint analysis over the above features defined clone-specific chromosomal aneuploidy in polyclonal populations., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
36. Global stratigraphic dataset composing LOK2016CS database: Biostratigraphic ranges of uppermost Tithonian-Hauterivian bioevents (Lower Cretaceous): Tables 1 and 2.
- Author
-
Scott RW
- Abstract
The Research article "Jurassic-Cretaceous boundary bioevents and magnetochrons: A stratigraphic experiment" (Scott, 2019), describes the Lower Cretaceous 2016 Chronostratigraphic Database (LOK2016CS). This database comprises the first and last occurrences of key fossil ranges in forty-one global stratigraphic sections (Table 1). This data has been published by qualified biostratigraphers in selected worldwide sections that have been carefully measured, collected and fossil species consistently identified. Regional reference sections and approved or proposed Global Boundary Stratotype Section and Point (GSSP) are included. This data set is composed of lowermost and uppermost positions of species measured in meters or feet by the research team in each section, which represent the first and last occurrences of the species. These data sets were composited into the numerical age chart, LOK2016CS (Table 2), by graphic correlation. The 2016 Geologic Time Scale was the X-axis section on the first X/Y plot so that the numerical ages were calibrated consistently with that scale. The numerical ages of each event estimate the First and Last Appearance Datums (FAD, LAD) within the geographic area encompassed by the sampled sections.
- Published
- 2019
- Full Text
- View/download PDF
37. The Genome Sequence of the Anthelmintic-Susceptible New Zealand Haemonchus contortus.
- Author
-
Palevich N, Maclean PH, Baten A, Scott RW, and Leathwick DM
- Subjects
- Animals, Base Sequence, Genomics, New Zealand, Anthelmintics pharmacology, Genome, Helminth genetics, Haemonchus drug effects, Haemonchus genetics
- Abstract
Internal parasitic nematodes are a global animal health issue causing drastic losses in livestock. Here, we report a H. contortus representative draft genome to serve as a genetic resource to the scientific community and support future experimental research of molecular mechanisms in related parasites. A de novo hybrid assembly was generated from PCR-free whole genome sequence data, resulting in a chromosome-level assembly that is 465 Mb in size encoding 22,341 genes. The genome sequence presented here is consistent with the genome architecture of the existing Haemonchus species and is a valuable resource for future studies regarding population genetic structures of parasitic nematodes. Additionally, comparative pan-genomics with other species of economically important parasitic nematodes have revealed highly open genomes and strong collinearities within the phylum Nematoda., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.)
- Published
- 2019
- Full Text
- View/download PDF
38. Small-Molecule Host-Defense Peptide Mimetic Antibacterial and Antifungal Agents Activate Human and Mouse Mast Cells via Mas-Related GPCRs.
- Author
-
Alkanfari I, Freeman KB, Roy S, Jahan T, Scott RW, and Ali H
- Subjects
- 3T3 Cells, Animals, Anti-Bacterial Agents chemistry, Antifungal Agents chemistry, Cell Degranulation drug effects, Fungi drug effects, Hep G2 Cells, Humans, Mast Cells drug effects, Mice, Mice, Inbred C57BL, Microbial Sensitivity Tests, Mutation, Missense genetics, Rats, Anti-Bacterial Agents pharmacology, Antifungal Agents pharmacology, Mast Cells metabolism, Nerve Tissue Proteins metabolism, Peptides pharmacology, Receptors, G-Protein-Coupled metabolism, Receptors, Neuropeptide metabolism, Small Molecule Libraries pharmacology
- Abstract
Host-defense peptides (HDPs) have an important therapeutic potential against microbial infections but their metabolic instability and cellular cytotoxicity have limited their utility. To overcome these limitations, we utilized five small-molecule, nonpeptide HDP mimetics (smHDPMs) and tested their effects on cytotoxicity, antimicrobial activity, and mast cell (MC) degranulation. None of the smHDPMs displayed cytotoxicity against mouse 3T3 fibroblasts or human transformed liver HepG2 cells. However, one compound had both antifungal and antibacterial activity. Surprisingly, all five compounds induced degranulation in a human MC line, LAD2, and this response was substantially reduced in Mas-related G protein-coupled receptor (GPCR)-X2 (MRGPRX2)-silenced cells. Furthermore, all five compounds induced degranulation in RBL-2H3 cells expressing MRGPRX2 but this response was abolished in cells expressing naturally occurring loss-of-function missense variants G165E (rs141744602) and D184H (rs372988289). Mrgprb2 is the likely mouse ortholog of human MRGPRX2, which is expressed in connective tissue MCs (CTMCs) such as cutaneous and peritoneal MCs (PMCs). All five smHDPMs induced degranulation in wild-type PMCs but not in cells derived from Mrgprb2⁻/⁻ mice. These findings suggest that smHDPMs could serve as novel targets for the treatment of drug-resistant fungal and bacterial infections because of their ability to harness CTMCs' host defense functions., Competing Interests: The authors have no financial conflicts of interest.
- Published
- 2019
- Full Text
- View/download PDF
39. Podocalyxin is required for maintaining blood-brain barrier function during acute inflammation.
- Author
-
Cait J, Hughes MR, Zeglinski MR, Chan AW, Osterhof S, Scott RW, Canals Hernaez D, Cait A, Vogl AW, Bernatchez P, Underhill TM, Granville DJ, Murphy TH, Roskelley CD, and McNagny KM
- Subjects
- Endothelial Cells cytology, Endothelial Cells metabolism, Human Umbilical Vein Endothelial Cells, Humans, Morphogenesis, Blood-Brain Barrier, Inflammation metabolism, Sialoglycoproteins metabolism
- Abstract
Podocalyxin (Podxl) is broadly expressed on the luminal face of most blood vessels in adult vertebrates, yet its function on these cells is poorly defined. In the present study, we identified specific functions for Podxl in maintaining endothelial barrier function. Using electrical cell substrate impedance sensing and live imaging, we found that, in the absence of Podxl, human umbilical vein endothelial cells fail to form an efficient barrier when plated on several extracellular matrix substrates. In addition, these monolayers lack adherens junctions and focal adhesions and display a disorganized cortical actin cytoskeleton. Thus, Podxl has a key role in promoting the appropriate endothelial morphogenesis required to form functional barriers. This conclusion is further supported by analyses of mutant mice in which we conditionally deleted a floxed allele of Podxl in vascular endothelial cells (vECs) using Tie2Cre mice ( Podxl
ΔTie2Cre ). Although we did not detect substantially altered permeability in naïve mice, systemic priming with lipopolysaccharide (LPS) selectively disrupted the blood-brain barrier (BBB) in PodxlΔTie2Cre mice. To study the potential consequence of this BBB breach, we used a selective agonist (TFLLR-NH2 ) of the protease-activated receptor-1 (PAR-1), a thrombin receptor expressed by vECs, neuronal cells, and glial cells. In response to systemic administration of TFLLR-NH2 , LPS-primed PodxlΔTie2Cre mice become completely immobilized for a 5-min period, coinciding with severely dampened neuroelectric activity. We conclude that Podxl expression by CNS tissue vECs is essential for BBB maintenance under inflammatory conditions., Competing Interests: The authors declare no conflict of interest.- Published
- 2019
- Full Text
- View/download PDF
40. Mutation and structure guided discovery of an antiviral small molecule that mimics an essential C-Terminal tripeptide of the vaccinia D4 processivity factor.
- Author
-
Nuth M, Guan H, Xiao Y, Kulp JL 3rd, Parker MH, Strobel ED, Isaacs SN, Scott RW, Reitz AB, and Ricciardi RP
- Subjects
- Antiviral Agents pharmacology, Drug Discovery, Inhibitory Concentration 50, Thiophenes chemistry, Vaccinia virus physiology, Virus Replication drug effects, Antiviral Agents chemistry, Molecular Mimicry, Mutation, Oligopeptides chemistry, Vaccinia virus drug effects, Viral Proteins chemistry
- Abstract
The smallpox virus (variola) remains a bioterrorism threat since a majority of the human population has never been vaccinated. In the event of an outbreak, at least two drugs against different targets of variola are critical to circumvent potential viral mutants that acquire resistance. Vaccinia virus (VACV) is the model virus used in the laboratory for studying smallpox. The VACV processivity factor D4 is an ideal therapeutic target since it is both essential and specific for poxvirus replication. Recently, we identified a tripeptide (Gly-Phe-Ile) motif at the C-terminus of D4 that is conserved among poxviruses and is necessary for maintaining protein function. In the current work, a virtual screening for small molecule mimics of the tripeptide identified a thiophene lead that effectively inhibited VACV, cowpox virus, and rabbitpox virus in cell culture (EC
50 = 8.4-19.7 μM) and blocked in vitro processive DNA synthesis (IC50 = 13.4 μM). Compound-binding to D4 was demonstrated through various biophysical methods and a dose-dependent retardation of the proteolysis of D4 proteins. This study highlights an inhibitor design strategy that exploits a susceptible region of the protein and identifies a novel scaffold for a broad-spectrum poxvirus inhibitor., (Copyright © 2018. Published by Elsevier B.V.)- Published
- 2019
- Full Text
- View/download PDF
41. Antifungal Potential of Host Defense Peptide Mimetics in a Mouse Model of Disseminated Candidiasis.
- Author
-
Chowdhury MH, Ryan LK, Cherabuddi K, Freeman KB, Weaver DG, Pelletier JC, Scott RW, and Diamond G
- Abstract
Invasive candidiasis caused by Candida albicans and non- albicans Candida (NAC) present a serious disease threat. Although the echinocandins are recommended as the first line of antifungal drug class, resistance to these agents is beginning to emerge, demonstrating the need for new antifungal agents. Host defense peptides (HDP) exhibit potent antifungal activity, but as drugs they are difficult to manufacture efficiently, and they are often inactivated by serum proteins. HDP mimetics are low molecular weight non-peptide compounds that can alleviate these problems and were shown to be membrane-active against C. albicans and NAC. Here, we expand upon our previous works to describe the in vitro and in vivo activity of 11 new HDP mimetics that are active against C. albicans and NAC that are both sensitive and resistant to standard antifungal drugs. These compounds exhibit minimum inhibitory/fungicidal concentration (MIC/MFC) in the µg/mL range in the presence of serum and are inhibited by divalent cations. Rapid propidium iodide influx into the yeast cells following in vitro exposure suggested that these HDP mimetics were also membrane active. The lead compounds were able to kill C. albicans in an invasive candidiasis CD-1 mouse model with some mimetic candidates decreasing kidney burden by 3-4 logs after 24 h in a dose-dependent manner. The data encouraged further development of this new anti-fungal drug class for invasive candidiasis., Competing Interests: Richard W. Scott owns stock in Cellceutix, Inc., which owns the patent on Compound . All other authors declare no financial interests.
- Published
- 2018
- Full Text
- View/download PDF
42. Potent in vitro and in vivo antifungal activity of a small molecule host defense peptide mimic through a membrane-active mechanism.
- Author
-
Menzel LP, Chowdhury HM, Masso-Silva JA, Ruddick W, Falkovsky K, Vorona R, Malsbary A, Cherabuddi K, Ryan LK, DiFranco KM, Brice DC, Costanzo MJ, Weaver D, Freeman KB, Scott RW, and Diamond G
- Subjects
- Antifungal Agents chemistry, Candida albicans drug effects, Candida albicans genetics, Candida albicans metabolism, Candida albicans ultrastructure, Complement C4 immunology, Disease Resistance, Drug Resistance, Fungal, Host-Derived Cellular Factors chemistry, Humans, Microbial Sensitivity Tests, Peptides chemistry, Antifungal Agents pharmacology, Host-Derived Cellular Factors pharmacology, Host-Pathogen Interactions genetics, Host-Pathogen Interactions immunology, Membranes drug effects, Peptides pharmacology
- Abstract
Lethal systemic fungal infections of Candida species are increasingly common, especially in immune compromised patients. By in vitro screening of small molecule mimics of naturally occurring host defense peptides (HDP), we have identified several active antifungal molecules, which also exhibited potent activity in two mouse models of oral candidiasis. Here we show that one such compound, C4, exhibits a mechanism of action that is similar to the parent HDP upon which it was designed. Specifically, its initial interaction with the anionic microbial membrane is electrostatic, as its fungicidal activity is inhibited by cations. We observed rapid membrane permeabilization to propidium iodide and ATP efflux in response to C4. Unlike the antifungal peptide histatin 5, it did not require energy-dependent transport across the membrane. Rapid membrane disruption was observed by both fluorescence and electron microscopy. The compound was highly active in vitro against numerous fluconazole-resistant clinical isolates of C. albicans and non-albicans species, and it exhibited potent, dose-dependent activity in a mouse model of invasive candidiasis, reducing kidney burden by three logs after 24 hours, and preventing mortality for up to 17 days. Together the results support the development of this class of antifungal drug to treat invasive candidiasis.
- Published
- 2017
- Full Text
- View/download PDF
43. Platinum Inhibits Low-Temperature Dry Lean Methane Combustion through Palladium Reduction in Pd-Pt/Al 2 O 3 : An In Situ X-ray Absorption Study.
- Author
-
Nassiri H, Lee KE, Hu Y, Hayes RE, Scott RW, and Semagina N
- Abstract
Palladium-platinum bimetallic catalysts supported on alumina with palladium/platinum molar ratios ranging from 0.25 to 4 are studied in dry lean methane combustion in the temperature range of 200 to 500 °C. Platinum addition decreases the catalyst activity, which cannot be explained by the decrease in dispersion or the structure sensitivity of the reaction. In situ X-ray absorption near-edge structure and extended X-ray absorption fine structure spectroscopy measurements have been conducted for monometallic Pd, Pt, and 2:1 Pd-Pt catalysts. Monometallic palladium is fully oxidized in the full temperature range, whereas platinum addition promotes palladium reduction, even in a reactive oxidizing environment. The Pd/PdO weight ratio in bimetallic Pd-Pt 2:1 catalysts decreases from 98/2 to 10/90 in the 200-500 °C temperature range under the reaction conditions. Thus, platinum promotes the formation of the reduced palladium phase with a significantly lower activity than that of oxidized palladium. The study sheds light on the effect of platinum on the state of the active palladium surface under low-temperature dry lean methane combustion conditions, which is important for methane-emission control devices., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2017
- Full Text
- View/download PDF
44. Mimics of Host Defense Proteins; Strategies for Translation to Therapeutic Applications.
- Author
-
Scott RW and Tew GN
- Subjects
- Humans, Anti-Infective Agents therapeutic use, Molecular Mimicry, Peptides therapeutic use
- Abstract
New infection treatments are urgently needed to combat the rising threat of multi-drug resistant bacteria. Despite early clinical set-backs attention has re-focused on host defense proteins (HDPs), as potential sources for new and effective antimicrobial treatments. HDPs appear to act at multiple targets and their repertoire includes disruptive membrane and intracellular activities against numerous types of pathogens as well as immune modulatory functions in the host. Importantly, these novel activities are associated with a low potential for emergence of resistance and little crossresistance with other antimicrobial agents. Based on these properties, HDPs appear to be ideal candidates for new antibiotics; however, their development has been plagued by the many therapeutic limitations associated with natural peptidic agents. This review focuses on HDP mimetic approaches aimed to improve metabolic stability, pharmacokinetics, safety and manufacturing processes. Early efforts with β-peptide or peptoid analogs focused on recreating stable facially amphiphilic structures but demonstrated that antimicrobial activity was modulated by more, complex structural properties. Several approaches have used lipidation to increase the hydrophobicity and membrane activity. One lead compound, LTX-109, has entered clinical study as a topical agent to treat impetigo and nasal decolonization. In a more significant departure from the amino acid like peptidomimetics, considerable effort has been directed at developing amphiphilic compounds that recapitulate the structural and biological properties of HDPs on small abiotic scaffolds. The lead compound from this approach, brilacidin, has completed two phase 2 studies as an intravenous agent for skin infections.
- Published
- 2017
- Full Text
- View/download PDF
45. Solving local structure around dopants in metal nanoparticles with ab initio modeling of X-ray absorption near edge structure.
- Author
-
Timoshenko J, Shivhare A, Scott RW, Lu D, and Frenkel AI
- Abstract
We adopted ab initio X-ray absorption near edge structure (XANES) modeling for structural refinement of local environments around metal impurities in a large variety of materials. Our method enables both direct modeling, where the candidate structures are known, and the inverse modeling, where the unknown structural motifs are deciphered from the experimental spectra. We present also estimates of systematic errors, and their influence on the stability and accuracy of the obtained results. We illustrate our approach by revealing the evolution of local environment of palladium atoms in palladium-doped gold thiolate clusters upon chemical and thermal treatments.
- Published
- 2016
- Full Text
- View/download PDF
46. Thermal degradation mechanism of triangular Ag@SiO2 nanoparticles.
- Author
-
Gangishetty MK, Scott RW, and Kelly TL
- Abstract
Triangular silver nanoparticles are promising materials for light harvesting applications because of their strong plasmon bands; these absorption bands are highly tunable, and can be varied over the entire visible range based on the particle size. A general concern with these materials is that they are unstable at elevated temperatures. When thermally annealed, they suffer from changes to the particle morphology, which in turn affects their optical properties. Because of this stability issue, these materials cannot be used in applications requiring elevated temperatures. In order to address this problem, it is important to first understand the degradation mechanism. Here, we measure the changes in particle morphology, oxidation state, and coordination environment of Ag@SiO2 nanotriangles caused by thermal annealing. UV-vis spectroscopy and TEM reveal that upon annealing the Ag@SiO2 nanotriangles in air, the triangular cores are truncated and smaller nanoparticles are formed. Ag K-edge X-ray absorption spectroscopy (XANES and EXAFS) shows that the small particles consist of Ag(0), and that there is a decrease in the Ag-Ag coordination number with an increase in the annealing temperature. We hypothesize that upon annealing Ag in air, it is first oxidized to AgxO, after which it subsequently decomposes back to well-dispersed Ag(0) nanoparticles. In contrast, when the Ag@SiO2 nanotriangles are annealed in N2, since there is no possibility of oxidation, no small particles are formed. Instead, the triangular core rearranges to form a disc-like shape.
- Published
- 2016
- Full Text
- View/download PDF
47. Effect of relative humidity on crystal growth, device performance and hysteresis in planar heterojunction perovskite solar cells.
- Author
-
Gangishetty MK, Scott RW, and Kelly TL
- Abstract
Due to the hygroscopic nature of organolead halide perovskites, humidity is one of the most important factors affecting the efficiency and longevity of perovskite solar cells. Although humidity has a long term detrimental effect on device performance, it also plays a key role during the initial growth of perovskite crystals. Here we demonstrate that atmospheric relative humidity (RH) plays a key role during the formation of perovskite thin films via the sequential deposition technique. Our results indicate that the RH has a substantial impact on the crystallization process, and hence on device performance. SEM and pXRD analysis show an increase in crystallite size with increasing humidity. At low RH, the formation of small cubic crystallites with large gaps between them is observed. The presence of these voids adversely affects device performance and leads to substantial hysteresis in the device. At higher RH, the perovskite crystals are larger in size, with better connectivity between the crystallites. This produced efficient planar heterojunction solar cells with low hysteresis. By careful control of the RH during the cell fabrication process, efficiencies of up to 12.2% are reached using P3HT as the hole-transport material.
- Published
- 2016
- Full Text
- View/download PDF
48. Impact of a CXCL12/CXCR4 Antagonist in Bleomycin (BLM) Induced Pulmonary Fibrosis and Carbon Tetrachloride (CCl4) Induced Hepatic Fibrosis in Mice.
- Author
-
Chow LN, Schreiner P, Ng BY, Lo B, Hughes MR, Scott RW, Gusti V, Lecour S, Simonson E, Manisali I, Barta I, McNagny KM, Crawford J, Webb M, and Underhill TM
- Subjects
- Aminoquinolines, Animals, Benzimidazoles, Bleomycin, Butylamines, Carbon Tetrachloride, Chemokine CXCL12 metabolism, Disease Models, Animal, Female, Heterocyclic Compounds, 1-Ring administration & dosage, Heterocyclic Compounds, 1-Ring pharmacokinetics, Heterocyclic Compounds, 1-Ring pharmacology, Liver Cirrhosis blood, Liver Cirrhosis chemically induced, Liver Cirrhosis complications, Lung pathology, Lymphocytes drug effects, Mice, Inbred C57BL, Pneumonia blood, Pneumonia complications, Pneumonia drug therapy, Pulmonary Fibrosis blood, Pulmonary Fibrosis chemically induced, Pulmonary Fibrosis complications, Receptors, CXCR4 metabolism, Transcription, Genetic drug effects, Chemokine CXCL12 antagonists & inhibitors, Heterocyclic Compounds, 1-Ring therapeutic use, Liver Cirrhosis drug therapy, Pulmonary Fibrosis drug therapy, Receptors, CXCR4 antagonists & inhibitors
- Abstract
Modulation of chemokine CXCL12 and its receptor CXCR4 has been implicated in attenuation of bleomycin (BLM)-induced pulmonary fibrosis and carbon tetrachloride (CCl4)-induced hepatic injury. In pulmonary fibrosis, published reports suggest that collagen production in the injured lung is derived from fibrocytes recruited from the circulation in response to release of pulmonary CXCL12. Conversely, in hepatic fibrosis, resident hepatic stellate cells (HSC), the key cell type in progression of fibrosis, upregulate CXCR4 expression in response to activation. Further, CXCL12 induces HSC proliferation and subsequent production of collagen I. In the current study, we evaluated AMD070, an orally bioavailable inhibitor of CXCL12/CXCR4 in alleviating BLM-induced pulmonary and CCl4-induced hepatic fibrosis in mice. Similar to other CXCR4 antagonists, treatment with AMD070 significantly increased leukocyte mobilization. However, in these two models of fibrosis, AMD070 had a negligible impact on extracellular matrix deposition. Interestingly, our results indicated that CXCL12/CXCR4 signaling has a role in improving mortality associated with BLM induced pulmonary injury, likely through dampening an early inflammatory response and/or vascular leakage. Together, these findings indicate that the CXCL12-CXCR4 signaling axis is not an effective target for reducing fibrosis.
- Published
- 2016
- Full Text
- View/download PDF
49. Methods and Strategies for Lineage Tracing of Mesenchymal Progenitor Cells.
- Author
-
Scott RW and Underhill TM
- Subjects
- Animals, Cell Differentiation, Cell Lineage, Cells, Cultured, Humans, Mesenchymal Stem Cells metabolism, Tissue Engineering, Cell Culture Techniques methods, Genes, Reporter, Mesenchymal Stem Cells cytology
- Abstract
Mesenchymal progenitors (MP) are found to varying extents in most tissues and organs. Their relationship to bone marrow-derived mesenchymal stem cells (MSCs) remains unclear, however, both populations appear to share a number of properties as defined by functional assays, clonogenic activity, and genetic and cell surface markers. MSCs were originally defined by their in vitro colony forming unit-fibroblast (CFU-F) activity and their ability to contribute to various mesenchymal lineages (i.e. cartilage, bone, and fat). MSCs also appear to exhibit some unique properties, in that expanded clones in the absence of bone-inducing factors generate bone spicules/organs in vivo. Subsequent analysis of these elements has demonstrated that the transplanted cells directly contribute to multiple mesenchymal lineages. Our ability to study MP and/or MSC behavior and lineage potential in vivo has been hampered by a lack of suitable Cre lines in which to effectively genetically mark and follow the fate and activity of these cells in development, growth, homeostasis and following injury or in disease. The emergence of several new genetic lines is enabling us to now address critical questions regarding MP/MSC location, behavior, function, and fate. The use of these lines and others in conjunction with suitable reporter lines will be described for MP/MSC cell fate analysis.
- Published
- 2016
- Full Text
- View/download PDF
50. Bricklebush (Brickellia) phylogeny reveals dimensions of the great Asteraceae radiation in Mexico.
- Author
-
Schilling EE, Panero JL, Crozier BS, Scott RW, and Dávila P
- Subjects
- Asteraceae genetics, DNA, Plant genetics, DNA, Ribosomal Spacer genetics, Mexico, Plastids genetics, Sequence Analysis, DNA, Asteraceae classification, Evolution, Molecular, Phylogeny
- Abstract
Data from molecular phylogenetics were used to assess aspects of diversity and relationships in Brickellia, a large and widespread genus of Eupatorieae. The dataset included sequence data from nuclear ribosomal ITS, ETS, and plastid psbA-trnH regions. An initial question was to assess the monophyly of the genus and whether Barroetea, Phanerostylis, and Kuhnia should be recognized as separate from or included in Brickellia. The results supported the hypothesis that Brickellia is monophyletic, with the small (2-3 species) Pleurocoronis as the sister group and showed Barroetea, Phanerostylis, and Kuhnia all embedded within the genus. Results of a time calibrated phylogeny from a BEAST analysis gave an estimated origination time for Brickellia at about 9 million years ago (Ma), with the oldest split within the genus dated at about 7.5Ma. A BAMM analysis based on the time calibrated tree showed that Brickellia has one rate shift in diversification associated with its origin in the late Miocene. Some lineages within the genus have had an increase in the rate of diversification over the past 5Ma, whereas other lineages have had a decrease in net diversification during this period. The results also elucidated nine clades within Brickellia which are accepted as taxonomic sections, and that will form logical units for future detailed studies., (Copyright © 2015 Elsevier Inc. All rights reserved.)
- Published
- 2015
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.