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1.
N Engl J Med ; 389(13): 1203-1210, 2023 Sep 28.
Article in English | MEDLINE | ID: mdl-37754285

ABSTRACT

We treated a 27-year-old patient with Duchenne's muscular dystrophy (DMD) with recombinant adeno-associated virus (rAAV) serotype 9 containing dSaCas9 (i.e., "dead" Staphylococcus aureus Cas9, in which the Cas9 nuclease activity has been inactivated) fused to VP64; this transgene was designed to up-regulate cortical dystrophin as a custom CRISPR-transactivator therapy. The dose of rAAV used was 1×1014 vector genomes per kilogram of body weight. Mild cardiac dysfunction and pericardial effusion developed, followed by acute respiratory distress syndrome (ARDS) and cardiac arrest 6 days after transgene treatment; the patient died 2 days later. A postmortem examination showed severe diffuse alveolar damage. Expression of transgene in the liver was minimal, and there was no evidence of AAV serotype 9 antibodies or effector T-cell reactivity in the organs. These findings indicate that an innate immune reaction caused ARDS in a patient with advanced DMD treated with high-dose rAAV gene therapy. (Funded by Cure Rare Disease.).


Subject(s)
Dystrophin , Genetic Therapy , Muscular Dystrophy, Duchenne , Respiratory Distress Syndrome , Transgenes , Adult , Humans , Antibodies , Dystrophin/genetics , Genetic Therapy/adverse effects , Genetic Therapy/methods , Muscular Dystrophy, Duchenne/genetics , Muscular Dystrophy, Duchenne/therapy , Respiratory Distress Syndrome/etiology , Respiratory Distress Syndrome/immunology , Transgenes/genetics , Transgenes/immunology , Fatal Outcome , Immunity, Innate/genetics , Immunity, Innate/immunology
2.
EMBO J ; 40(9): e104888, 2021 05 03.
Article in English | MEDLINE | ID: mdl-33630350

ABSTRACT

Endoplasmic reticulum (ER) calcium (Ca2+ ) stores are critical to proteostasis, intracellular signaling, and cellular bioenergetics. Through forward genetic screening in mice, we identified two members of a new complex, Pacs1 and Wdr37, which are required for normal ER Ca2+ handling in lymphocytes. Deletion of Pacs1 or Wdr37 caused peripheral lymphopenia that was linked to blunted Ca2+ release from the ER after antigen receptor stimulation. Pacs1-deficient cells showed diminished inositol triphosphate receptor expression together with increased ER and oxidative stress. Mature Pacs1-/- B cells proliferated and died in vivo under lymphocyte replete conditions, indicating spontaneous loss of cellular quiescence. Disruption of Pacs1-Wdr37 did not diminish adaptive immune responses, but potently suppressed lymphoproliferative disease models by forcing loss of quiescence. Thus, Pacs1-Wdr37 plays a critical role in stabilizing lymphocyte populations through ER Ca2+ handling and presents a new target for lymphoproliferative disease therapy.


Subject(s)
Endoplasmic Reticulum/metabolism , Gene Deletion , Lymphopenia/genetics , Lymphoproliferative Disorders/genetics , Nuclear Proteins/genetics , Vesicular Transport Proteins/genetics , Animals , B-Lymphocytes/metabolism , Calcium Signaling , Disease Models, Animal , Female , HEK293 Cells , Humans , Lymphopenia/metabolism , Lymphoproliferative Disorders/metabolism , Male , Mice , NIH 3T3 Cells , Nuclear Proteins/metabolism , Vesicular Transport Proteins/metabolism
3.
Proc Natl Acad Sci U S A ; 119(18): e2200128119, 2022 05 03.
Article in English | MEDLINE | ID: mdl-35482923

ABSTRACT

Null mutations of spliceosome components or cofactors are homozygous lethal in eukaryotes, but viable hypomorphic mutations provide an opportunity to understand the physiological impact of individual splicing proteins. We describe a viable missense allele (F181I) of Rnps1 encoding an essential regulator of splicing and nonsense-mediated decay (NMD), identified in a mouse genetic screen for altered immune cell development. Homozygous mice displayed a stem cell­intrinsic defect in hematopoiesis of all lineages due to excessive apoptosis induced by tumor necrosis factor (TNF)­dependent death signaling. Numerous transcript splice variants containing retained introns and skipped exons were detected at elevated frequencies in Rnps1F181I/F181I splenic CD8+ T cells and hematopoietic stem cells (HSCs), but NMD appeared normal. Strikingly, Tnf knockout rescued all hematopoietic cells to normal or near-normal levels in Rnps1F181I/F181I mice and dramatically reduced intron retention in Rnps1F181I/F181I CD8+ T cells and HSCs. Thus, RNPS1 is necessary for accurate splicing, without which disinhibited TNF signaling triggers hematopoietic cell death.


Subject(s)
CD8-Positive T-Lymphocytes , Ribonucleoproteins , Animals , CD8-Positive T-Lymphocytes/metabolism , Hematopoiesis/genetics , Homozygote , Mammals/metabolism , Mice , Receptors, Tumor Necrosis Factor/metabolism , Ribonucleoproteins/metabolism , Sequence Deletion , Tumor Necrosis Factors/metabolism
4.
J Infect Dis ; 2023 Sep 12.
Article in English | MEDLINE | ID: mdl-37698016

ABSTRACT

BACKGROUND: Chronic pulmonary conditions such as asthma and COPD increase the risk of morbidity and mortality during infection with the Middle East respiratory syndrome coronavirus (MERS-CoV). We hypothesized that individuals with such comorbidities are more susceptible to MERS-CoV infection due to increased expression of its receptor, dipeptidyl peptidase 4 (DPP4). METHODS: We modeled chronic airway disease by treating primary human airway epithelia with the Th2 cytokine IL-13, examining how this impacted DPP4 protein levels along with MERS-CoV entry and replication. RESULTS: IL-13 exposure for 3 days led to increased DPP4 protein abundance, while a 21-day treatment increased DPP4 levels and caused goblet cell metaplasia. Surprisingly, despite this increase in receptor availability, MERS-CoV entry and replication were not significantly impacted by IL-13 treatment. CONCLUSIONS: Our results suggest that increased DPP4 abundance is likely not the primary mechanism leading to increased MERS severity in the setting of Th2 inflammation. Transcriptional profiling analysis highlighted the complexity of IL-13 induced changes in airway epithelia, including altered expression of genes involved in innate immunity, antiviral responses, and maintenance of the extracellular mucus barrier. These data suggest that additional factors likely interact with DPP4 abundance to determine MERS-CoV infection outcomes.

5.
Proc Natl Acad Sci U S A ; 117(21): 11829-11835, 2020 05 26.
Article in English | MEDLINE | ID: mdl-32381739

ABSTRACT

Loss of KBTBD2 in all tissues causes the teeny phenotype, characterized by insulin resistance with late failure of insulin production, severe hyperglycemia/diabetes, lipodystrophy, hepatosteatosis, and growth retardation. KBTBD2 maintains insulin sensitivity in adipocytes by restricting the abundance of p85α. However, the possible physiological contribution or contributions of KBTBD2 have not yet been examined in other tissues. Here we show that mice with an adipocyte-specific knockout of Kbtbd2 accumulate p85α in white and brown adipose tissues, causing insulin resistance, moderate rather than severe hyperglycemia, sustained hyperinsulinemia without late failure of insulin production, and lipodystrophy leading to ectopic lipid accumulation in the liver. Adipocyte-extrinsic insulin resistance was observed in liver and muscle. None of these abnormalities were observed in liver- or muscle-specific Kbtbd2 knockout mice. Mice with Kbtbd2 knockout in adipocytes, liver, and muscle all showed normal growth, suggesting that KBTBD2 may be necessary to ensure IGF1 signaling in other tissues, notably bone. While much of the teeny phenotype results from loss of KBTBD2 in adipocytes, some features are adipocyte-extrinsic.


Subject(s)
Adipocytes/metabolism , Insulin Resistance/physiology , Lipodystrophy/metabolism , Ubiquitin-Protein Ligase Complexes/metabolism , Animals , Class Ia Phosphatidylinositol 3-Kinase/metabolism , Diabetes Mellitus/metabolism , Male , Mice , Mice, Knockout , Organ Specificity/physiology , Phenotype
6.
Proc Natl Acad Sci U S A ; 117(9): 4894-4901, 2020 03 03.
Article in English | MEDLINE | ID: mdl-32071239

ABSTRACT

γ-secretase is an intramembrane protease complex that catalyzes the proteolytic cleavage of amyloid precursor protein and Notch. Impaired γ-secretase function is associated with the development of Alzheimer's disease and familial acne inversa in humans. In a forward genetic screen of mice with N-ethyl-N-nitrosourea-induced mutations for defects in adaptive immunity, we identified animals within a single pedigree exhibiting both hypopigmentation of the fur and diminished T cell-independent (TI) antibody responses. The causative mutation was in Ncstn, an essential gene encoding the protein nicastrin (NCSTN), a member of the γ-secretase complex that functions to recruit substrates for proteolysis. The missense mutation severely limits the glycosylation of NCSTN to its mature form and impairs the integrity of the γ-secretase complex as well as its catalytic activity toward its substrate Notch, a critical regulator of B cell and T cell development. Strikingly, however, this missense mutation affects B cell development but not thymocyte or T cell development. The Ncstn allele uncovered in these studies reveals an essential requirement for NCSTN during the type 2 transitional-marginal zone precursor stage and peritoneal B-1 B cell development, the TI antibody response, fur pigmentation, and intestinal homeostasis in mice.


Subject(s)
Amyloid Precursor Protein Secretases/metabolism , Amyloid beta-Protein Precursor/genetics , Amyloid beta-Protein Precursor/metabolism , B-Lymphocyte Subsets/metabolism , Gene Expression Regulation, Developmental , Membrane Glycoproteins/genetics , Membrane Glycoproteins/metabolism , Adaptive Immunity , Alzheimer Disease/metabolism , Animals , Cell Membrane/metabolism , Ethylnitrosourea/adverse effects , Female , Hidradenitis Suppurativa/metabolism , Humans , Hypopigmentation , Male , Mice , Mice, Inbred C57BL , Mutation , Pedigree , T-Lymphocytes/metabolism , Transcriptome
7.
PLoS Genet ; 16(6): e1008830, 2020 06.
Article in English | MEDLINE | ID: mdl-32502192

ABSTRACT

Many post-transcriptional mechanisms operate via mRNA 3'UTRs to regulate protein expression, and such controls are crucial for development. We show that homozygous mutations in two zebrafish exon junction complex (EJC) core genes rbm8a and magoh leads to muscle disorganization, neural cell death, and motor neuron outgrowth defects, as well as dysregulation of mRNAs subjected to nonsense-mediated mRNA decay (NMD) due to translation termination ≥ 50 nts upstream of the last exon-exon junction. Intriguingly, we find that EJC-dependent NMD also regulates a subset of transcripts that contain 3'UTR introns (3'UI) < 50 nts downstream of a stop codon. Some transcripts containing such stop codon-proximal 3'UI are also NMD-sensitive in cultured human cells and mouse embryonic stem cells. We identify 167 genes that contain a conserved proximal 3'UI in zebrafish, mouse and humans. foxo3b is one such proximal 3'UI-containing gene that is upregulated in zebrafish EJC mutant embryos, at both mRNA and protein levels, and loss of foxo3b function in EJC mutant embryos significantly rescues motor axon growth defects. These data are consistent with EJC-dependent NMD regulating foxo3b mRNA to control protein expression during zebrafish development. Our work shows that the EJC is critical for normal zebrafish development and suggests that proximal 3'UIs may serve gene regulatory function in vertebrates.


Subject(s)
Forkhead Transcription Factors/metabolism , Gene Expression Regulation, Developmental , Neurogenesis/genetics , Nonsense Mediated mRNA Decay/genetics , RNA-Binding Proteins/metabolism , Zebrafish Proteins/metabolism , 3' Untranslated Regions/genetics , Animals , Animals, Genetically Modified , Axons/physiology , Codon, Terminator , Datasets as Topic , Embryo, Nonmammalian , Exons/genetics , Gene Regulatory Networks/genetics , Homozygote , Humans , Introns/genetics , Mice , Muscle, Skeletal/innervation , Mutagenesis , Mutation , Neuronal Outgrowth/genetics , Nuclear Proteins/genetics , Peptide Chain Termination, Translational , RNA, Messenger/metabolism , RNA-Binding Proteins/genetics , RNA-Seq , Sequence Alignment , Up-Regulation , Zebrafish/genetics , Zebrafish/growth & development
9.
Nicotine Tob Res ; 24(1): 135-140, 2022 01 01.
Article in English | MEDLINE | ID: mdl-34255068

ABSTRACT

INTRODUCTION: This study examined whether exposure to reduced-nicotine-content cigarettes (RNCCs) for 12 weeks alters respiratory health using Fractional Exhaled Nitric Oxide (FeNO), a validated biomarker of respiratory epithelial health, and the Respiratory Health Questionnaire (RHQ), a subject-rated questionnaire on respiratory symptoms. Participants were 747 adult daily smokers enrolled in three double-blind, randomized clinical trials evaluating effects of cigarette nicotine content (0.4, 2.4, 15.8 mg nicotine/g tobacco) in people with affective disorders, opioid use disorder (OUD), or socioeconomic disadvantage. AIMS AND METHODS: FeNO levels and RHQ ratings were collected at baseline and Weeks 6 and 12 following randomization. Multiple regression was used to assess associations of FeNO and RHQ with smoking characteristics. Mixed-model repeated-measures ANOVA was used to evaluate the effects of nicotine content on FeNO and RHQ outcomes over the 12-week study period. RESULTS: FeNO levels but not RHQ ratings varied inversely with smoking characteristics at baseline (Ps < 0.0001) in smokers with affective disorders and socioeconomic disadvantage but less so in those with OUD. Participants with affective disorders and socioeconomic disadvantage, but not those with OUD, who were assigned to RNCCs had higher FeNO levels at Week 12 than those assigned to the 15.8 mg/g dose [F(2,423) = 4.51, p = .01, Cohen's d = 0.21]. No significant dose-related changes in RHQ scores were identified. CONCLUSIONS: Use of RNCCs across a 12-week period attenuates smoking-related reductions in FeNO levels in smokers with affective disorders and socioeconomic disadvantage although not those with OUD. FeNO changes were not accompanied by changes in respiratory-health ratings. TRIAL REGISTRATION: Inclusion and exclusion criteria for the sample and experimental manipulation of the nicotine content of assigned cigarettes are registered: NCT02232737, NCT02250664, NCT02250534. The FeNO measure reported in this manuscript is an exploratory outcome that was not registered. IMPLICATIONS: Should a reduced nicotine content standard be implemented; these results suggest that reduced nicotine content in cigarettes will not exacerbate and instead may attenuate smoking-related decreases in FeNO. This is significant as NO is an important component in maintaining a healthy respiratory system and necessary to defend against infection. Furthermore, the results of the current study demonstrate that the adoption of the reduced nicotine content standard may result in beneficial impacts on respiratory epithelial health among vulnerable populations that are disproportionally affected by the adverse health outcomes precipitated by combustible tobacco use.


Subject(s)
Smoking Cessation , Tobacco Products , Adult , Fractional Exhaled Nitric Oxide Testing , Humans , Nicotine , Outcome Assessment, Health Care , Respiratory System , Self Report , Smokers , Socioeconomic Factors
10.
Dev Biol ; 462(2): 129-140, 2020 06 15.
Article in English | MEDLINE | ID: mdl-32246943

ABSTRACT

Vertebrate segmentation is regulated by the segmentation clock, a biological oscillator that controls periodic formation of somites, or embryonic segments, which give rise to many mesodermal tissue types. This molecular oscillator generates cyclic gene expression with the same periodicity as somite formation in the presomitic mesoderm (PSM), an area of mesenchymal cells that give rise to mature somites. Molecular components of the clock include the Hes/her family of genes that encode transcriptional repressors, but additional genes cycle. Cyclic gene transcripts are cleared rapidly, and clearance depends upon the pnrc2 (proline-rich nuclear receptor co-activator 2) gene that encodes an mRNA decay adaptor. Previously, we showed that the her1 3'UTR confers instability to otherwise stable transcripts in a Pnrc2-dependent manner, however, the molecular mechanism(s) by which cyclic gene transcripts are cleared remained largely unknown. To identify features of the her1 3'UTR that are critical for Pnrc2-mediated decay, we developed an array of transgenic inducible reporter lines carrying different regions of the 3'UTR. We find that the terminal 179 nucleotides (nts) of the her1 3'UTR are necessary and sufficient to confer rapid instability. Additionally, we show that the 3'UTR of another cyclic gene, deltaC (dlc), also confers Pnrc2-dependent instability. Motif analysis reveals that both her1 and dlc 3'UTRs contain terminally-located Pumilio response elements (PREs) and AU-rich elements (AREs), and we show that the PRE and ARE in the last 179 â€‹nts of the her1 3'UTR drive rapid turnover of reporter mRNA. Finally, we show that mutation of Pnrc2 residues and domains that are known to facilitate interaction of human PNRC2 with decay factors DCP1A and UPF1 reduce the ability of Pnrc2 to restore normal cyclic gene expression in pnrc2 mutant embryos. Our findings suggest that Pnrc2 interacts with decay machinery components and cooperates with Pumilio (Pum) proteins and ARE-binding proteins to promote rapid turnover of cyclic gene transcripts during somitogenesis.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/genetics , Basic Helix-Loop-Helix Transcription Factors/metabolism , RNA Stability/physiology , Trans-Activators/genetics , Trans-Activators/metabolism , Zebrafish Proteins/genetics , Zebrafish Proteins/metabolism , 3' Untranslated Regions , Animals , Biological Clocks/genetics , Body Patterning/genetics , Embryonic Development , Endoribonucleases/genetics , Endoribonucleases/metabolism , Gene Expression Regulation, Developmental , Mesoderm/embryology , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , RNA Stability/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptors, Cytoplasmic and Nuclear/genetics , Somites/metabolism , Transcription Factors/metabolism , Zebrafish/embryology
11.
HPB (Oxford) ; 22(8): 1128-1134, 2020 08.
Article in English | MEDLINE | ID: mdl-32565039

ABSTRACT

BACKGROUND: The extent of the COVID-19 pandemic and the resulting response has varied globally. The European and African Hepato-Pancreato-Biliary Association (E-AHPBA), the premier representative body for practicing HPB surgeons in Europe and Africa, conducted this survey to assess the impact of COVID-19 on HPB surgery. METHODS: An online survey was disseminated to all E-AHPBA members to assess the effects of the pandemic on unit capacity, management of HPB cancers, use of COVID-19 screening and other aspects of service delivery. RESULTS: Overall, 145 (25%) members responded. Most units, particularly in COVID-high countries (>100,000 cases) reported insufficient critical care capacity and reduced HPB operating sessions compared to COVID-low countries. Delayed access to cancer surgery necessitated alternatives including increased neoadjuvant chemotherapy for pancreatic cancer and colorectal liver metastases, and locoregional treatments for hepatocellular carcinoma. Other aspects of service delivery including COVID-19 screening and personal protective equipment varied between units and countries. CONCLUSION: This study demonstrates that the COVID-19 pandemic has had a profound adverse impact on the delivery of HPB cancer care across the continents of Europe and Africa. The findings illustrate the need for safe resumption of cancer surgery in a "new" normal world with screening of patients and staff for COVID-19.


Subject(s)
Betacoronavirus , Biliary Tract Neoplasms/surgery , Coronavirus Infections/complications , Digestive System Surgical Procedures/methods , Liver Neoplasms/surgery , Pancreatic Neoplasms/surgery , Pneumonia, Viral/complications , Africa/epidemiology , Biliary Tract Neoplasms/complications , COVID-19 , Coronavirus Infections/epidemiology , Cross-Sectional Studies , Delivery of Health Care/methods , Europe/epidemiology , Female , Humans , Liver Neoplasms/complications , Male , Pancreatic Neoplasms/complications , Pandemics , Pneumonia, Viral/epidemiology , SARS-CoV-2 , Societies, Medical
12.
Cancer Invest ; 37(1): 39-45, 2019.
Article in English | MEDLINE | ID: mdl-30676118

ABSTRACT

Genetic test use in oncology is growing, yet providers' experiences with evolving testing norms and their implications for patient care remain under-explored. In interviews with oncologists and cancer genetics professionals, 22 key informants described the increasing importance of germline results for therapeutic decision-making, preference for ordering tests directly rather than referring, and rapid adoption of cancer gene panels for testing. Implications for informed consent, result interpretation, and patient management were identified. These results suggest concerns raised by the transition of genetic test delivery from cancer genetics professionals to oncologists that must be addressed in practice guidelines and provider training.


Subject(s)
Genetic Testing/methods , Germ-Line Mutation , Neoplasms/genetics , Clinical Decision-Making , Female , Genetic Counseling , Humans , Male , Medical Oncology , Practice Guidelines as Topic , Qualitative Research
13.
J Natl Compr Canc Netw ; 17(11): 1278-1285, 2019 11 01.
Article in English | MEDLINE | ID: mdl-31693980

ABSTRACT

The NCCN Guidelines for Kidney Cancer provide multidisciplinary recommendations for the clinical management of patients with clear cell and non-clear cell renal cell carcinoma, and are intended to assist with clinical decision-making. These NCCN Guidelines Insights summarize the NCCN Kidney Cancer Panel discussions for the 2020 update to the guidelines regarding initial management and first-line systemic therapy options for patients with advanced clear cell renal cell carcinoma.


Subject(s)
Carcinoma, Renal Cell , Kidney Neoplasms , Kidney Neoplasms/therapy , Humans , Carcinoma, Renal Cell/therapy , Clinical Decision-Making
14.
HEC Forum ; 31(3): 167-175, 2019 Sep.
Article in English | MEDLINE | ID: mdl-30178165

ABSTRACT

A general consensus has been reached in health care organizations that the disclosure of medical errors can be a very powerful way to improve patients and physicians well-being and serves as a core component to high quality health care. This practice strongly encourages transparent communication with patients after medical errors or unanticipated outcomes. However, many countries, such as Brazil, do not have a culture of disclosing harmful errors to patients or standards emphasizing the importance of disclosing, taking responsibility, apologizing, and discussing the prevention of recurrences. Medical error is not discussed or approached during medical school. The stigma of error has a strong connection with value judgments, and emotional support for physicians does not exist. This paper suggests that open communication with the patient is essential. Guidance about error disclosure from health care organizations would be helpful for quality and patient safety and for health care professionals in countries like Brazil.


Subject(s)
Cultural Competency/psychology , Medical Errors/psychology , Physicians/psychology , Attitude of Health Personnel , Brazil , Humans , Patient Safety/standards , Patient Safety/statistics & numerical data , Physicians/standards , Quality Improvement , Risk Management , Truth Disclosure/ethics
15.
Dev Biol ; 429(1): 225-239, 2017 09 01.
Article in English | MEDLINE | ID: mdl-28648842

ABSTRACT

Vertebrate segmentation is controlled by the segmentation clock, a molecular oscillator that regulates gene expression and cycles rapidly. The expression of many genes oscillates during segmentation, including hairy/Enhancer of split-related (her or Hes) genes, which encode transcriptional repressors that auto-inhibit their own expression, and deltaC (dlc), which encodes a Notch ligand. We previously identified the tortuga (tor) locus in a zebrafish forward genetic screen for genes involved in cyclic transcript regulation and showed that cyclic transcripts accumulate post-splicing in tor mutants. Here we show that cyclic mRNA accumulation in tor mutants is due to loss of pnrc2, which encodes a proline-rich nuclear receptor co-activator implicated in mRNA decay. Using an inducible in vivo reporter system to analyze transcript stability, we find that the her1 3'UTR confers Pnrc2-dependent instability to a heterologous transcript. her1 mRNA decay is Dicer-independent and likely employs a Pnrc2-Upf1-containing mRNA decay complex. Surprisingly, despite accumulation of cyclic transcripts in pnrc2-deficient embryos, we find that cyclic protein is expressed normally. Overall, we show that Pnrc2 promotes 3'UTR-mediated decay of developmentally-regulated segmentation clock transcripts and we uncover an additional post-transcriptional regulatory layer that ensures oscillatory protein expression in the absence of cyclic mRNA decay.


Subject(s)
3' Untranslated Regions/genetics , Biological Clocks/genetics , Body Patterning/genetics , Trans-Activators/metabolism , Zebrafish Proteins/metabolism , Zebrafish/embryology , Zebrafish/genetics , Alleles , Animals , Basic Helix-Loop-Helix Transcription Factors/genetics , Basic Helix-Loop-Helix Transcription Factors/metabolism , Chromosomes/genetics , Chromosomes, Artificial, Bacterial/genetics , Embryo, Nonmammalian/metabolism , Gene Expression Regulation, Developmental , Genes, Reporter , Mutation/genetics , Nonsense Mediated mRNA Decay/genetics , Phenotype , RNA Stability/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Trans-Activators/genetics , Zebrafish Proteins/genetics , Zygote/metabolism
16.
Dev Biol ; 424(2): 162-180, 2017 04 15.
Article in English | MEDLINE | ID: mdl-28279710

ABSTRACT

Satellite cells, also known as muscle stem cells, are responsible for skeletal muscle growth and repair in mammals. Pax7 and Pax3 transcription factors are established satellite cell markers required for muscle development and regeneration, and there is great interest in identifying additional factors that regulate satellite cell proliferation, differentiation, and/or skeletal muscle regeneration. Due to the powerful regenerative capacity of many zebrafish tissues, even in adults, we are exploring the regenerative potential of adult zebrafish skeletal muscle. Here, we show that adult zebrafish skeletal muscle contains cells similar to mammalian satellite cells. Adult zebrafish satellite-like cells have dense heterochromatin, express Pax7 and Pax3, proliferate in response to injury, and show peak myogenic responses 4-5 days post-injury (dpi). Furthermore, using a pax7a-driven GFP reporter, we present evidence implicating satellite-like cells as a possible source of new muscle. In lieu of central nucleation, which distinguishes regenerating myofibers in mammals, we describe several characteristics that robustly identify newly-forming myofibers from surrounding fibers in injured adult zebrafish muscle. These characteristics include partially overlapping expression in satellite-like cells and regenerating myofibers of two RNA-binding proteins Rbfox2 and Rbfoxl1, known to regulate embryonic muscle development and function. Finally, by analyzing pax7a; pax7b double mutant zebrafish, we show that Pax7 is required for adult skeletal muscle repair, as it is in the mouse.


Subject(s)
Aging/physiology , Muscle, Skeletal/pathology , PAX2 Transcription Factor/metabolism , Satellite Cells, Skeletal Muscle/metabolism , Wound Healing , Zebrafish Proteins/metabolism , Zebrafish/metabolism , Animals , Animals, Genetically Modified , Base Sequence , Cell Differentiation , Cell Nucleus/metabolism , Cell Proliferation , Green Fluorescent Proteins/metabolism , Models, Biological , Muscle Development , Muscle Fibers, Skeletal/metabolism , Muscle Fibers, Skeletal/pathology , Muscle, Skeletal/ultrastructure , Satellite Cells, Skeletal Muscle/pathology , Satellite Cells, Skeletal Muscle/ultrastructure , Transgenes
18.
Am Heart J ; 200: 75-82, 2018 06.
Article in English | MEDLINE | ID: mdl-29898852

ABSTRACT

BACKGROUND: Capturing and incorporating patient-centered factors into 30-day readmission risk prediction after hospitalized heart failure (HF) could improve the modest performance of current models. METHODS: Using a mixed-methods approach, we developed a patient-centered survey and evaluated the additional predictive utility of the survey compared to a traditional readmission risk model (the Krumholz et al. model). Area under the receiver operating characteristic curve (AUC) and the Hosmer-Lemeshow goodness-of-fit statistic quantified the performance of both models. We measured the amount of model improvement with the addition of patient-centered factors to the Krumholz et al. model with the integrated discrimination improvement (IDI). In an exploratory analysis, we used hierarchical clustering algorithms to identify groups with similar survey responses and tested for differences between clusters using standard descriptive statistics. RESULTS: From 3/24/2014 to 3/12/2015, 183 patients hospitalized with HF were enrolled from an urban, academic health system and followed for 30days after discharge. The Krumholz et al. plus patient-centered factors model had similar-to-slightly lower performance (AUC [95%CI]:0.62 [0.52, 0.71]; goodness-of-fit P=.10) than the Krumholz et al. model (AUC [95%CI]:0.66 [0.57, 0.76]; goodness-of-fit P=.19). The IDI (95%CI) was 0.003 (-0.014,0.020). We identified three patient clusters based on patient-centered survey responses. The clusters differed with respect to gender, self-rated health, employment status, and prior hospitalization frequency (all P<.05). CONCLUSIONS: The addition of patient-centered factors did not improve 30-day readmission model performance. Rather than designing interventions based on predicted readmission risk, tailoring interventions to all patients, based on their characteristics, could inform the design of targeted, readmission reduction strategies.


Subject(s)
Heart Failure , Patient Readmission/statistics & numerical data , Patient-Centered Care/methods , Aged , Area Under Curve , Cluster Analysis , Comorbidity , Demography , Female , Heart Failure/epidemiology , Heart Failure/therapy , Hospitalization/statistics & numerical data , Humans , Male , Middle Aged , Patient Discharge , ROC Curve , Risk Assessment/methods , Risk Factors , Socioeconomic Factors , Surveys and Questionnaires , United States
19.
J Org Chem ; 83(16): 9076-9087, 2018 08 17.
Article in English | MEDLINE | ID: mdl-30033724

ABSTRACT

A series of chlorin monomers and dyads has been prepared to probe the effect of ethenyl vs ethynyl linkers on the electronic conjugation and optical properties in resulting derivatives. Styryl-substituted chlorins have been prepared either by a Heck reaction or by microwave-assisted olefin metathesis, while ß-ß ethenyl-linked dyads have been synthesized from the corresponding vinyl-substituted chlorin monomer using microwave-assisted olefin metathesis. It has been found that when an ethenyl linker is connected at the ß-position of chlorin it provides stronger electronic conjugation than an ethynyl one, which is manifested by a greater bathochromic shift of the longest wavelength absorption (Q y) and emission bands. Stronger electronic coupling is particularly evident for dyads, where ethenyl-linked dyad exhibits a strong near-IR absorption band emission (λabs = 707 nm, λem = 712 nm, Φf = 0.45), compared to the deep-red absorption and emission of a corresponding ethynyl-linked dyad (λabs = 689 nm, λem = 691 nm, Φf = 0.48). The reactivity of ethenyl-linked dyads with singlet oxygen is discussed as well. The results reported here provide further guidelines for molecular design of deep-red and near-IR absorbing and intensely emitting chlorin derivatives and chlorins with extended π-electronic conjugation for a variety of photonic applications.

20.
Med Teach ; 40(10): 1060-1066, 2018 10.
Article in English | MEDLINE | ID: mdl-29065748

ABSTRACT

Medical educators are expected to teach quality improvement (QI) skills alongside traditional clinical skills such as physical examination and bedside manner. Educational resources for intensive training in QI have proliferated. However, many physicians lack the time or resources to undergo this training, and may struggle with teaching these skills to their learners. In response, we offer twelve tips to help physicians teach basic QI concepts in the clinical environment. By following these tips physicians will be able to engage their learners interest in QI and provide experiential learning that makes a lasting impact.


Subject(s)
Quality Improvement/organization & administration , Teaching/organization & administration , Checklist , Communication , Education, Medical , Faculty, Medical , Health Behavior , Humans , Organizational Culture , Outcome and Process Assessment, Health Care , Patient-Centered Care/organization & administration , Quality of Health Care/organization & administration , Root Cause Analysis
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