Publications by authors named "Michael Kaufman"

101 Publications

Adult liver transplant anesthesiology practice patterns and resource utilization in the United States: Survey results from the society for the advancement of transplant anesthesia.

Clin Transplant 2021 Oct 12:e14504. Epub 2021 Oct 12.

Department of Anesthesiology, University of Colorado, Aurora, CO.

Introduction: Liver transplant anesthesiology is an evolving and expanding subspecialty, and programs have, in the past, exhibited significant variations of practice at transplant centers across the United States. In order to explore current practice patterns, the Quality & Standards Committee from the Society for the Advancement of Transplant Anesthesia (SATA) undertook a survey of liver transplant anesthesiology program directors.

Methods: Program directors were invited to participate in an online questionnaire. A total of 110 program directors were identified from the 2018 Scientific Registry of Transplant Recipients (SRTR) database. Replies were received from 65 programs (response rate of 59%).

Results: Our results indicate an increase in transplant anesthesia fellowship training and advanced training in transesophageal echocardiography (TEE). We also find that the use of intraoperative TEE and viscoelastic testing is more common. However, there has been a reduction in the use of veno-venous bypass, routine placement of pulmonary artery catheters and the intraoperative use of anti-fibrinolytics when compared to prior surveys.

Conclusion: The results show considerable heterogeneity in practice patterns across the country that continues to evolve. However, there appears to be a movement towards the adoption of specific structural and clinical practices. This article is protected by copyright. All rights reserved.
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http://dx.doi.org/10.1111/ctr.14504DOI Listing
October 2021

Vimseltinib: A Precision CSF1R Therapy for Tenosynovial Giant Cell Tumors and Diseases Promoted by Macrophages.

Mol Cancer Ther 2021 Aug 25. Epub 2021 Aug 25.

Deciphera Pharmaceuticals, LLC, Waltham, Massachusetts.

Macrophages can be co-opted to contribute to neoplastic, neurologic, and inflammatory diseases. Colony-stimulating factor 1 receptor (CSF1R)-dependent macrophages and other inflammatory cells can suppress the adaptive immune system in cancer and contribute to angiogenesis, tumor growth, and metastasis. CSF1R-expressing osteoclasts mediate bone degradation in osteolytic cancers and cancers that metastasize to bone. In the rare disease tenosynovial giant cell tumor (TGCT), aberrant CSF1 expression and production driven by a gene translocation leads to the recruitment and growth of tumors formed by CSF1R-dependent inflammatory cells. Small molecules and antibodies targeting the CSF1/CSF1R axis have shown promise in the treatment of TGCT and cancer, with pexidartinib recently receiving FDA approval for treatment of TGCT. Many small-molecule kinase inhibitors of CSF1R also inhibit the closely related kinases KIT, PDGFRA, PDGFRB, and FLT3, thus CSF1R suppression may be limited by off-target activity and associated adverse events. Vimseltinib (DCC-3014) is an oral, switch control tyrosine kinase inhibitor specifically designed to selectively and potently inhibit CSF1R by exploiting unique features of the switch control region that regulates kinase conformational activation. In preclinical studies, vimseltinib durably suppressed CSF1R activity and , depleted macrophages and other CSF1R-dependent cells, and resulted in inhibition of tumor growth and bone degradation in mouse cancer models. Translationally, in a phase I clinical study, vimseltinib treatment led to modulation of biomarkers of CSF1R inhibition and reduction in tumor burden in TGCT patients.
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http://dx.doi.org/10.1158/1535-7163.MCT-21-0361DOI Listing
August 2021

Initiation of Otx2 expression in the developing mouse retina requires a unique enhancer and either Ascl1 or Neurog2 activity.

Development 2021 06 18;148(12). Epub 2021 Jun 18.

Department of Ophthalmology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.

During retinal development, a large subset of progenitors upregulates the transcription factor Otx2, which is required for photoreceptor and bipolar cell formation. How these retinal progenitor cells initially activate Otx2 expression is unclear. To address this, we investigated the cis-regulatory network that controls Otx2 expression in mice. We identified a minimal enhancer element, DHS-4D, that drove expression in newly formed OTX2+ cells. CRISPR/Cas9-mediated deletion of DHS-4D reduced OTX2 expression, but this effect was diminished in postnatal development. Systematic mutagenesis of the enhancer revealed that three basic helix-loop-helix (bHLH) transcription factor-binding sites were required for its activity. Single cell RNA-sequencing of nascent Otx2+ cells identified the bHLH factors Ascl1 and Neurog2 as candidate regulators. CRISPR/Cas9 targeting of these factors showed that only the simultaneous loss of Ascl1 and Neurog2 prevented OTX2 expression. Our findings suggest that Ascl1 and Neurog2 act either redundantly or in a compensatory fashion to activate the DHS-4D enhancer and Otx2 expression. We observed redundancy or compensation at both the transcriptional and enhancer utilization levels, suggesting that the mechanisms governing Otx2 regulation in the retina are flexible and robust.
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http://dx.doi.org/10.1242/dev.199399DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8254865PMC
June 2021

Assessing seizure burden in pediatric epilepsy using an electronic medical record-based tool through a common data element approach.

Epilepsia 2021 07 2;62(7):1617-1628. Epub 2021 Jun 2.

Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, USA.

Objective: Improvement in epilepsy care requires standardized methods to assess disease severity. We report the results of implementing common data elements (CDEs) to document epilepsy history data in the electronic medical record (EMR) after 12 months of clinical use in outpatient encounters.

Methods: Data regarding seizure frequency were collected during routine clinical encounters using a CDE-based form within our EMR. We extracted CDE data from the EMR and developed measurements for seizure severity and seizure improvement scores. Seizure burden and improvement was evaluated by patient demographic and encounter variables for in-person and telemedicine encounters.

Results: We assessed a total of 1696 encounters in 1038 individuals with childhood epilepsies between September 6, 2019 and September 11, 2020 contributed by 32 distinct providers. Childhood absence epilepsy (n = 121), Lennox-Gastaut syndrome (n = 86), and Dravet syndrome (n = 42) were the most common epilepsy syndromes. Overall, 43% (737/1696) of individuals had at least monthly seizures, 17% (296/1696) had a least daily seizures, and 18% (311/1696) were seizure-free for >12 months. Quantification of absolute seizure burden and changes in seizure burden over time differed between epilepsy syndromes, including high and persistent seizure burden in patients with Lennox-Gastaut syndrome. Individuals seen via telemedicine or in-person encounters had comparable seizure frequencies. Individuals identifying as Hispanic/Latino, particularly from postal codes with lower median household incomes, were more likely to have ongoing seizures that worsened over time.

Significance: Standardized documentation of clinical data in childhood epilepsies through CDE can be implemented in routine clinical care at scale and enables assessment of disease burden, including characterization of seizure burden over time. Our data provide insights into heterogeneous patterns of seizure control in common pediatric epilepsy syndromes and will inform future initiatives focusing on patient-centered outcomes in childhood epilepsies, including the impact of telemedicine and health care disparities.
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http://dx.doi.org/10.1111/epi.16934DOI Listing
July 2021

Phenotypic homogeneity in childhood epilepsies evolves in gene-specific patterns across 3251 patient-years of clinical data.

Eur J Hum Genet 2021 May 24. Epub 2021 May 24.

The Epilepsy NeuroGenetics Initiative (ENGIN), Children's Hospital of Philadelphia, Philadelphia, PA, USA.

While genetic studies of epilepsies can be performed in thousands of individuals, phenotyping remains a manual, non-scalable task. A particular challenge is capturing the evolution of complex phenotypes with age. Here, we present a novel approach, applying phenotypic similarity analysis to a total of 3251 patient-years of longitudinal electronic medical record data from a previously reported cohort of 658 individuals with genetic epilepsies. After mapping clinical data to the Human Phenotype Ontology, we determined the phenotypic similarity of individuals sharing each genetic etiology within each 3-month age interval from birth up to a maximum age of 25 years. 140 of 600 (23%) of all 27 genes and 3-month age intervals with sufficient data for calculation of phenotypic similarity were significantly higher than expect by chance. 11 of 27 genetic etiologies had significant overall phenotypic similarity trajectories. These do not simply reflect strong statistical associations with single phenotypic features but appear to emerge from complex clinical constellations of features that may not be strongly associated individually. As an attempt to reconstruct the cognitive framework of syndrome recognition in clinical practice, longitudinal phenotypic similarity analysis extends the traditional phenotyping approach by utilizing data from electronic medical records at a scale that is far beyond the capabilities of manual phenotyping. Delineation of how the phenotypic homogeneity of genetic epilepsies varies with age could improve the phenotypic classification of these disorders, the accuracy of prognostic counseling, and by providing historical control data, the design and interpretation of precision clinical trials in rare diseases.
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http://dx.doi.org/10.1038/s41431-021-00908-8DOI Listing
May 2021

The combination of coronary sinus ostial atresia/abnormalities and a small persistent left superior vena cava-Opportunity for left ventricular lead implantation and unrecognized source of thromboembolic stroke.

Heart Rhythm 2021 Jul 8;18(7):1064-1073. Epub 2021 May 8.

Division of Cardiology, Department of Medicine, Columbia University College of Physicians and Surgeon, New York, New York.

Background: Coronary sinus (CS) ostial atresia/abnormalities prevent access to the CS from the right atrium (RA) for left ventricular (LV) lead implantation. Some patients with CS ostial abnormalities also have a small persistent left superior vena cava (sPLSVC).

Objective: The purpose of this study was to describe CS ostial abnormalities and sPLSVC as an opportunity for LV lead implantation and unrecognized source of stroke.

Methods: Twenty patients with CS ostial abnormalities and sPLSVC were identified. Clinical information, imaging methods, LV lead implantation techniques, and complications were summarized.

Results: Forty percent had at least 1 previously unsuccessful LV lead placement. In 70%, sPLSVC was identified by catheter manipulation and contrast injection in the left brachiocephalic vein, and in 30% by levophase CS venography. In 30%, sPLSVC was associated with drainage from the CS into the left atrium (LA). When associated with CS ostial abnormalities, the sPLSVC diameter averaged 5.6 ± 3 mm. sPLSVC was used for successful LV lead implantation in 90% of cases. In 80%, the LV lead was implanted down sPLSVC, and in 20%, sPLSVC was used to access the CS from the RA. Presumably because of unrecognized drainage from the CS to the LA, 1 patient had a stroke during implantation via sPLSVC.

Conclusion: When CS ostial abnormalities prevent access to the CS from the RA, sPLSVC can be used to successfully implant LV leads. In some, the CS partially drains into the LA and stroke can occur spontaneously or during lead intervention. It is important to distinguish sPLSVC associated with CS ostial abnormalities from isolated PLSVC.
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http://dx.doi.org/10.1016/j.hrthm.2021.05.004DOI Listing
July 2021

Gene delivery using AAV8 for disease stabilization in a bimodal gene therapy approach for the treatment of ADA-deficient SCID.

Mol Ther Methods Clin Dev 2021 Mar 15;20:765-778. Epub 2021 Feb 15.

Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA.

Adenosine deaminase (ADA) deficiency is an inborn error of metabolism affecting multiple systems and causing severe combined immunodeficiency. We tested intravenous administration of recombinant adeno-associated virus (AAV) 2/8-ADA vector in ADA-deficient neonate and adult mice or as part of a bimodal approach comprised of rAAV treatment at birth followed by infusion of lentiviral vector (LV)-modified lineage-depleted bone marrow cells at 8 weeks. ADA mice treated with rAAV and enzyme replacement therapy (ERT) for 30 days were rescued from the lethal pulmonary insufficiency, surviving out to 180 days without further treatment. rAAV vector copy number (VCN) was highest in liver, lung, and heart and was associated with near-normal ADA activity and thymocyte development. In the bimodal approach, rAAV-mediated expression supported survival during the 4 weeks before infusion of the LV-modified bone marrow cells and during the engraftment period. Conditioning prior to infusion may have resulted in the replacement of rAAV marked cells in marrow and liver, with LV VCN 100- to 1,000-fold higher in hematopoietic tissue compared with rAAV VCN, and was associated with immune cell reconstitution. In conclusion, a bimodal approach may be an alternative for patients without reliable access to ERT before receiving a stem cell transplant or gene therapy.
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http://dx.doi.org/10.1016/j.omtm.2021.02.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7940710PMC
March 2021

Computational analysis of 10,860 phenotypic annotations in individuals with SCN2A-related disorders.

Genet Med 2021 07 17;23(7):1263-1272. Epub 2021 Mar 17.

Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, USA.

Purpose: Pathogenic variants in SCN2A cause a wide range of neurodevelopmental phenotypes. Reports of genotype-phenotype correlations are often anecdotal, and the available phenotypic data have not been systematically analyzed.

Methods: We extracted phenotypic information from primary descriptions of SCN2A-related disorders in the literature between 2001 and 2019, which we coded in Human Phenotype Ontology (HPO) terms. With higher-level phenotype terms inferred by the HPO structure, we assessed the frequencies of clinical features and investigated the association of these features with variant classes and locations within the Na1.2 protein.

Results: We identified 413 unrelated individuals and derived a total of 10,860 HPO terms with 562 unique terms. Protein-truncating variants were associated with autism and behavioral abnormalities. Missense variants were associated with neonatal onset, epileptic spasms, and seizures, regardless of type. Phenotypic similarity was identified in 8/62 recurrent SCN2A variants. Three independent principal components accounted for 33% of the phenotypic variance, allowing for separation of gain-of-function versus loss-of-function variants with good performance.

Conclusion: Our work shows that translating clinical features into a computable format using a standardized language allows for quantitative phenotype analysis, mapping the phenotypic landscape of SCN2A-related disorders in unprecedented detail and revealing genotype-phenotype correlations along a multidimensional spectrum.
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http://dx.doi.org/10.1038/s41436-021-01120-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8257493PMC
July 2021

Simultaneous deletion of and enhancers in the retina alters photoreceptor and bipolar cell fate specification, yet differs from deleting both genes.

Development 2020 07 3;147(13). Epub 2020 Jul 3.

Sue Anschutz Rodgers Eye Center, Department of Ophthalmology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA

The transcription factor OTX2 is required for photoreceptor and bipolar cell formation in the retina. It directly activates the transcription factors and through cell type-specific enhancers. PRDM1 and VSX2 work in opposition, such that PRDM1 promotes photoreceptor fate and VSX2 bipolar cell fate. To determine how OTX2+ cell fates are regulated in mice, we deleted and or their cell type-specific enhancers simultaneously using a CRISPR/Cas9 retina electroporation strategy. Double gene or enhancer targeting effectively removed PRDM1 and VSX2 protein expression. However, double enhancer targeting favored bipolar fate outcomes, whereas double gene targeting favored photoreceptor fate. Both conditions generated excess amacrine cells. Combined, these fate changes suggest that photoreceptors are a default fate outcome in OTX2+ cells and that VSX2 must be present in a narrow temporal window to drive bipolar cell formation. and also appear to redundantly restrict the competence of OTX2+ cells, preventing amacrine cell formation. By taking a combinatorial deletion approach of both coding sequences and enhancers, our work provides new insights into the complex regulatory mechanisms that control cell fate choice.
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http://dx.doi.org/10.1242/dev.190272DOI Listing
July 2020

Analyzing 2,589 child neurology telehealth encounters necessitated by the COVID-19 pandemic.

Neurology 2020 09 9;95(9):e1257-e1266. Epub 2020 Jun 9.

From the Division of Neurology (S.C.R., S.E.F., A.K.G., J.X., P.D.G., M.K., M.S.P., U.S., M.P.F., S.E.M., M.P.M., S.K.K., D.J.S.., B.L.B., N.S.A., I.H.), Department of Biomedical and Health Informatics (A.K.G., J.X., P.D.G., M.K., I.H.), and The Epilepsy NeuroGenetics Initiative (A.K.G., J.X., P.D.G., M.K., M.P.F., S.K.K., N.S.A., I.H.), Children's Hospital of Philadelphia; and Departments of Neurology and Pediatrics (S.C.R., S.E.F., M.S.P., M.P.F., S.K.K., N.S.A., I.H.), Department of Biostatistics, Epidemiology and Informatics (N.S.A.), and Department of Anesthesia & Critical Care (N.S.A.), University of Pennsylvania Perelman School of Medicine, Philadelphia.

Objective: To assess the rapid implementation of child neurology telehealth outpatient care with the onset of the coronavirus disease 2019 (COVID-19) pandemic in March 2020.

Methods: This was a cohort study with retrospective comparison of 14,780 in-person encounters and 2,589 telehealth encounters, including 2,093 audio-video telemedicine and 496 scheduled telephone encounters, between October 1, 2019 and April 24, 2020. We compared in-person and telehealth encounters for patient demographics and diagnoses. For audio-video telemedicine encounters, we analyzed questionnaire responses addressing provider experience, follow-up plans, technical quality, need for in-person assessment, and parent/caregiver satisfaction. We performed manual reviews of encounters flagged as concerning by providers.

Results: There were no differences in patient age and major ICD-10 codes before and after transition. Clinicians considered telemedicine satisfactory in 93% (1,200 of 1,286) of encounters and suggested telemedicine as a component for follow-up care in 89% (1,144 of 1,286) of encounters. Technical challenges were reported in 40% (519 of 1,314) of encounters. In-person assessment was considered warranted after 5% (65 of 1,285) of encounters. Patients/caregivers indicated interest in telemedicine for future care in 86% (187 of 217) of encounters. Participation in telemedicine encounters compared to telephone encounters was less frequent among patients in racial or ethnic minority groups.

Conclusions: We effectively converted most of our outpatient care to telehealth encounters, including mostly audio-video telemedicine encounters. Providers rated the vast majority of telemedicine encounters to be satisfactory, and only a small proportion of encounters required short-term in-person follow-up. These findings suggest that telemedicine is feasible and effective for a large proportion of child neurology care. Additional strategies are needed to ensure equitable telemedicine use.
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http://dx.doi.org/10.1212/WNL.0000000000010010DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7538222PMC
September 2020

[THE MISTAKE OF CUT AND PASTE FROM ACUTE PAIN TO CHRONIC PAIN].

Harefuah 2020 Mar;159(3):201-205

Advanced Pain Centre Modiin, Pain/Rehabilitation Center Sheba Hospital.

Introduction: What is a physician to do when the tools in his toolbox fail him? In the field of chronic pain, we are told that imaging studies are often so non-specific as to barely distinguish between symptomatic and asymptomatic individuals. "Advanced pain management techniques and off-label use of popular pain medicines do not withstand the rigors of controlled clinical trials and in many cases have been shown to be harmful. We are informed by the CDC that we are in the midst of a deadly "physician-driven" epidemic of prescribed opioid use disorder. The British Medical Society refers to "our silent addicts" explaining that pregabalin is the "new valium". The manufacturers of oxycodone, pregabalin and duloxetine have been successfully sued for up to $650 million for having overstated the benefits and understated the risks of their products. There has been a huge accumulation of scientific literature over 30 years demonstrating that pain-related beliefs, attitudes and behaviors are the most powerful predictors of outcome: more so than depression, anxiety, PTSD or personality type. All this confusion begs for a change of approach and treatment platform. This article wishes to introduce the reader to a different set of safer, more evidence-based tools to consider when faced with a problematic chronic pain patient.
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March 2020

Dosing and Re-Administration of Lentiviral Vector for Gene Therapy in Rhesus Monkeys and ADA-Deficient Mice.

Mol Ther Methods Clin Dev 2020 Mar 16;16:78-93. Epub 2019 Nov 16.

Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA.

Adenosine deaminase (ADA)-deficient mice and healthy rhesus monkeys were studied to determine the impact of age at treatment, vector dosage, dosing schedule, repeat administration, biodistribution, and immunogenicity after systemic delivery of lentiviral vectors (LVs). In mice, neonatal treatment resulted in broad vector marking across all tissues analyzed, whereas adult treatment resulted in marking restricted to the liver, spleen, and bone marrow. Intravenous administration to infant rhesus monkeys also resulted in dose-dependent marking in the liver, spleen, and bone marrow. Using an ELISA to monitor anti-vector antibody development, neonatal mice did not produce an antibody response, whereas adult mice produced a strong antibody response to vector administration. In mice and monkeys with repeat administration of LV, a strong anti-vector antibody response was shown in response to the second LV administration, which resulted in LV inactivation. Three separate doses administered to immune competent mice resulted in acute toxicity. Pegylation of the vesicular stomatitis virus G protein (VSV-G)-enveloped LVs showed a less robust anti-vector response but did not prevent the inactivation of the second LV administration. These studies identify important factors to consider related to age and timing of administration when implementing systemic delivery of LVs as a potential therapeutic agent.
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http://dx.doi.org/10.1016/j.omtm.2019.11.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6909201PMC
March 2020

A Phase I Study of LY3009120, a Pan-RAF Inhibitor, in Patients with Advanced or Metastatic Cancer.

Mol Cancer Ther 2020 02 23;19(2):460-467. Epub 2019 Oct 23.

Department of Investigational Cancer Therapeutics, University of Texas MD Anderson Cancer Center, Houston, Texas.

Mutations in ERK signaling drive a significant percentage of malignancies. LY3009120, a pan-RAF and dimer inhibitor, has preclinical activity in - and -mutated cell lines including -mutant melanoma resistant to BRAF inhibitors. This multicenter, open-label, phase I clinical trial (NCT02014116) consisted of part A (dose escalation) and part B (dose confirmation) in patients with advanced/metastatic cancer. In part A, oral LY3009120 was dose escalated from 50 to 700 mg twice a day on a 28-day cycle. In part B, 300 mg LY3009120 was given twice a day. The primary objective was to identify a recommended phase II dose (RP2D). Secondary objectives were to evaluate safety, pharmacokinetics, and preliminary efficacy. Identification of pharmacodynamic biomarkers was exploratory. In parts A and B, 35 and 16 patients were treated, respectively ( = 51). In part A, 6 patients experienced eight dose-limiting toxicities. The RP2D was 300 mg twice a day. Common (>10%) any-grade drug-related treatment-emergent adverse events were fatigue ( = 15), nausea ( = 12), dermatitis acneiform ( = 10), decreased appetite ( = 7), and maculopapular rash ( = 7). The median duration of treatment was 4 weeks; 84% of patients completed one or two cycles of treatment. Exposures observed at 300 mg twice a day were above the preclinical concentration associated with tumor regression. Eight patients had a best overall response of stable disease; there were no complete or partial clinical responses. Despite adequate plasma exposure levels, predicted pharmacodynamic effects were not observed.
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http://dx.doi.org/10.1158/1535-7163.MCT-19-0681DOI Listing
February 2020

Transcriptional profiling of murine retinas undergoing semi-synchronous cone photoreceptor differentiation.

Dev Biol 2019 09 1;453(2):155-167. Epub 2019 Jun 1.

Department of Ophthalmology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA. Electronic address:

Uncovering the gene regulatory networks that control cone photoreceptor formation has been hindered because cones only make up a few percent of the retina and form asynchronously during development. To overcome these limitations, we used a γ-secretase inhibitor, DAPT, to disrupt Notch signaling and force proliferating retinal progenitor cells to rapidly adopt neuronal identity. We treated mouse retinal explants at the peak of cone genesis with DAPT and examined tissues at several time-points by histology and bulk RNA-sequencing. We found that this treatment caused supernumerary cone formation in an overwhelmingly synchronized fashion. This analysis revealed several categorical patterns of gene expression changes over time relative to DMSO treated control explants. These were placed in the temporal context of the activation of Otx2, a transcription factor that is expressed at the onset of photoreceptor development and that is required for both rod and cone formation. One group of interest had genes, such as Mybl1, Ascl1, Neurog2, and Olig2, that became upregulated by DAPT treatment before Otx2. Two other groups showed upregulated gene expression shortly after Otx2, either transiently or permanently. This included genes such as Mybl1, Meis2, and Podxl. Our data provide a developmental timeline of the gene expression events that underlie the initial steps of cone genesis and maturation. Applying this strategy to human retinal organoid cultures was also sufficient to induce a massive increase in cone genesis. Taken together, our results provide a temporal framework that can be used to elucidate the gene regulatory logic controlling cone photoreceptor development.
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http://dx.doi.org/10.1016/j.ydbio.2019.05.016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7722777PMC
September 2019

Phase Identification of the Layered Perovskite Ce SrMnO and Application for Solar Thermochemical Water Splitting.

Inorg Chem 2019 Jun 30;58(12):7705-7714. Epub 2019 May 30.

Metallurgical and Materials Engineering Department , Colorado School of Mines , Golden , Colorado , United States.

Ruddlesden-Popper (layered perovskite) phases are attracting significant interest because of their unique potential for many applications requiring mixed ionic and electronic conductivity. Here we report a new, previously undiscovered layered perovskite of composition, Ce SrMnO ( x = 0.1, 0.2, and 0.3). Furthermore, we demonstrate that this new system is suitable for solar thermochemical hydrogen production (STCH). Synchrotron radiation X-ray diffraction and transmission electron microscopy are performed to characterize this new system. Density functional theory calculations of phase stability and oxygen vacancy formation energy (1.76, 2.24, and 2.66 eV/O atom, respectively with increasing Ce content) reinforce the potential of this phase for STCH application. Experimental hydrogen production results show that this materials system produces 2-3 times more hydrogen than the benchmark STCH oxide ceria at a reduction temperature of 1400 °C and an oxidation temperature of 1000 °C.
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http://dx.doi.org/10.1021/acs.inorgchem.8b03487DOI Listing
June 2019

Ripretinib (DCC-2618) Is a Switch Control Kinase Inhibitor of a Broad Spectrum of Oncogenic and Drug-Resistant KIT and PDGFRA Variants.

Cancer Cell 2019 05;35(5):738-751.e9

Deciphera Pharmaceuticals, Inc., Waltham, MA 02451, USA. Electronic address:

Ripretinib (DCC-2618) was designed to inhibit the full spectrum of mutant KIT and PDGFRA kinases found in cancers and myeloproliferative neoplasms, particularly in gastrointestinal stromal tumors (GISTs), in which the heterogeneity of drug-resistant KIT mutations is a major challenge. Ripretinib is a "switch-control" kinase inhibitor that forces the activation loop (or activation "switch") into an inactive conformation. Ripretinib inhibits all tested KIT and PDGFRA mutants, and notably is a type II kinase inhibitor demonstrated to broadly inhibit activation loop mutations in KIT and PDGFRA, previously thought only achievable with type I inhibitors. Ripretinib shows efficacy in preclinical cancer models, and preliminary clinical data provide proof-of-concept that ripretinib inhibits a wide range of KIT mutants in patients with drug-resistant GISTs.
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http://dx.doi.org/10.1016/j.ccell.2019.04.006DOI Listing
May 2019

Improving Gene Editing Outcomes in Human Hematopoietic Stem and Progenitor Cells by Temporal Control of DNA Repair.

Stem Cells 2019 02 27;37(2):284-294. Epub 2018 Nov 27.

Department of Molecular and Medical Pharmacology, University of California Los Angeles (UCLA), Los Angeles, California, USA.

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated system (Cas9)-mediated gene editing of human hematopoietic stem cells (hHSCs) is a promising strategy for the treatment of genetic blood diseases through site-specific correction of identified causal mutations. However, clinical translation is hindered by low ratio of precise gene modification using the corrective donor template (homology-directed repair, HDR) to gene disruption (nonhomologous end joining, NHEJ) in hHSCs. By using a modified version of Cas9 with reduced nuclease activity in G1 phase of cell cycle when HDR cannot occur, and transiently increasing the proportion of cells in HDR-preferred phases (S/G2), we achieved a four-fold improvement in HDR/NHEJ ratio over the control condition in vitro, and a significant improvement after xenotransplantation of edited hHSCs into immunodeficient mice. This strategy for improving gene editing outcomes in hHSCs has important implications for the field of gene therapy, and can be applied to diseases where increased HDR/NHEJ ratio is critical for therapeutic success. Stem Cells 2019;37:284-294.
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http://dx.doi.org/10.1002/stem.2935DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6368869PMC
February 2019

Gene Therapy for Sickle Cell Disease: A Lentiviral Vector Comparison Study.

Hum Gene Ther 2018 10;29(10):1153-1166

1 Department of Microbiology, Immunology, and Molecular Genetics, University of California , Los Angeles, California; University of Modena and Reggio Emilia , Italy .

Sickle cell disease (SCD) is an inherited blood disorder caused by a single amino acid substitution in the β-globin chain of hemoglobin. Gene therapy is a promising therapeutic alternative, particularly in patients lacking an allogeneic bone marrow (BM) donor. One of the major challenges for an effective gene therapy approach is the design of an efficient vector that combines high-level and long-term β-globin expression with high infectivity in primary CD34+ cells. Two lentiviral vectors carrying an anti-sickling β-globin transgene (AS3) were directly compared: the Lenti/βAS3-FB, and Globe-AS3 with and without the FB insulator. The comparison was performed initially in human BM CD34+ cells derived from SCD patients in an in vitro model of erythroid differentiation. Additionally, the comparison was carried out in two in vivo models: First, an NOD SCID gamma mouse model was used to compare transduction efficiency and β-globin expression in human BM CD34+ cells after transplant. Second, a sickle mouse model was used to analyze β-globin expression produced from the vectors tested, as well as hematologic correction of the sickle phenotype. While minor differences were found in the vectors in the in vitro study (2.4-fold higher vector copy number in CD34+ cells when using Globe-AS3), no differences were noted in the overall correction of the SCD phenotype in the in vivo mouse model. This study provides a comprehensive in vitro and in vivo analysis of two globin lentiviral vectors, which is useful for determining the optimal candidate for SCD gene therapy.
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http://dx.doi.org/10.1089/hum.2018.061DOI Listing
October 2018

Awake vs Sedated Tracheostomies: A Review and Comparison at a Single Institution.

Otolaryngol Head Neck Surg 2018 11 17;159(5):830-834. Epub 2018 Jul 17.

1 Department of Otolaryngology, University of Kentucky Medical Center, Lexington, Kentucky, USA.

Objective: The literature surrounding awake tracheostomies is sparse, particularly comparing awake tracheostomy patients to that of the sedated tracheostomy population. This study sought to compare tracheostomy patient demographics, indications, and outcomes of the 2 populations.

Study Design: Case series with chart review.

Setting: Tertiary care center.

Materials And Methods: All tracheostomies performed at our tertiary academic medical institution between January 2013 through November 2015 were reviewed. The data collected included demographics, comorbidity, anticoagulation, and outcomes.

Results: A total of 978 tracheostomies performed during this period met inclusion criteria, with 78 (8.0%) on awake patients. Most awake procedures were performed by otolaryngology (97.4%). Male sex predominated (73.1% awake vs 57.8% sedated). Forty-four patients (56.4%) were smokers in the awake group vs 326 of 900 (36.2%) in the sedated group. Malignancy was the primary indication for awake tracheostomy (68/78, 87.1%). One patient (1.3%) had significant postoperative bleeding compared to 26 of 900 (2.9%) of the sedated tracheostomy patients ( P = .406). Only 9 (11.4%) were ever decannulated. Thirty-one (39.2%) patients ultimately underwent total laryngectomy, 3 could not be decannulated secondary to anatomical causes (stenosis or vocal fold paralysis), and 19 were lost to follow-up after discharge. There were 12 of 78 (15.4%) overall deaths in the awake cohort, with 215 of 900 (23.9%) in the sedated cohort ( P = .088).

Conclusion: Despite all the differences between the 2 patient populations, the urgent awake tracheostomy appears to be safe and its complications do not appear significantly different from the sedated population.
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http://dx.doi.org/10.1177/0194599818789079DOI Listing
November 2018

High Throughput Discovery and Design of Strong Multicomponent Metallic Solid Solutions.

Sci Rep 2018 Jun 5;8(1):8600. Epub 2018 Jun 5.

Center for Advanced Non-Ferrous Structural Alloys, George S. Ansell Department of Metallurgical and Materials Engineering, Colorado School of Mines, Golden, CO, 80401, USA.

High Entropy Alloys (HEAs) are new classes of structural metallic materials that show remarkable property combinations. Yet, often times interesting compositions are still found by trial and error. Here we show an "Effective Atomic Radii for Strength" (EARS) methodology, together with different semi-empirical and first-principle models, can be used to predict the extent of solid solution strengthening to discover and design new HEAs with unprecedented properties. We have designed a CrNiCo alloy with a yield strength over 50% greater with equivalent ductility than the strongest HEA (CrNiCo) from the CrMnFeNiCo family reported to date. We show that values determined by the EARS methodology are more physically representative of multicomponent concentrated solid solutions. Our methodology permits high throughput, property-driven discovery and design of HEAs, enabling the development of future high-performance advanced materials for extreme environments.
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http://dx.doi.org/10.1038/s41598-018-26830-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5988724PMC
June 2018

Site-Specific Gene Editing of Human Hematopoietic Stem Cells for X-Linked Hyper-IgM Syndrome.

Cell Rep 2018 05;23(9):2606-2616

Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA; Division of Hematology & Oncology, Department of Pediatrics, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, CA 90095, USA.

X-linked hyper-immunoglobulin M (hyper-IgM) syndrome (XHIM) is a primary immunodeficiency due to mutations in CD40 ligand that affect immunoglobulin class-switch recombination and somatic hypermutation. The disease is amenable to gene therapy using retroviral vectors, but dysregulated gene expression results in abnormal lymphoproliferation in mouse models, highlighting the need for alternative strategies. Here, we demonstrate the ability of both the transcription activator-like effector nuclease (TALEN) and clustered regularly interspaced short palindromic repeats-associated protein 9 (CRISPR/Cas9) platforms to efficiently drive integration of a normal copy of the CD40L cDNA delivered by Adeno-Associated Virus. Site-specific insertion of the donor sequence downstream of the endogenous CD40L promoter maintained physiologic expression of CD40L while overriding all reported downstream mutations. High levels of gene modification were achieved in primary human hematopoietic stem cells (HSCs), as well as in cell lines and XHIM-patient-derived T cells. Notably, gene-corrected HSCs engrafted in immunodeficient mice at clinically relevant frequencies. These studies provide the foundation for a permanent curative therapy in XHIM.
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http://dx.doi.org/10.1016/j.celrep.2018.04.103DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6181643PMC
May 2018

Characterization of Gene Alterations following Editing of the β-Globin Gene Locus in Hematopoietic Stem/Progenitor Cells.

Mol Ther 2018 02 9;26(2):468-479. Epub 2017 Nov 9.

Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA. Electronic address:

The use of engineered nucleases combined with a homologous DNA donor template can result in targeted gene correction of the sickle cell disease mutation in hematopoietic stem and progenitor cells. However, because of the high homology between the adjacent human β- and δ-globin genes, off-target cleavage is observed at δ-globin when using some endonucleases targeted to the sickle mutation in β-globin. Introduction of multiple double-stranded breaks by endonucleases has the potential to induce intergenic alterations. Using a novel droplet digital PCR assay and high-throughput sequencing, we characterized the frequency of rearrangements between the β- and δ-globin paralogs when delivering these nucleases. Pooled CD34 cells and colony-forming units from sickle bone marrow were treated with nuclease only or including a donor template and then analyzed for potential gene rearrangements. It was observed that, in pooled CD34 cells and colony-forming units, the intergenic β-δ-globin deletion was the most frequent rearrangement, followed by inversion of the intergenic fragment, with the inter-chromosomal translocation as the least frequent. No rearrangements were observed when endonuclease activity was restricted to on-target β-globin cleavage. These findings demonstrate the need to develop site-specific endonucleases with high specificity to avoid unwanted gene alterations.
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http://dx.doi.org/10.1016/j.ymthe.2017.11.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5835144PMC
February 2018

Benzocaine-Induced Methemoglobinemia.

J Emerg Med 2017 12 6;53(6):912-913. Epub 2017 Nov 6.

Department of Otolaryngology, Head and Neck Surgery, University of Kentucky, Lexington, Kentucky.

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http://dx.doi.org/10.1016/j.jemermed.2017.09.004DOI Listing
December 2017

The Selective Tie2 Inhibitor Rebastinib Blocks Recruitment and Function of Tie2 Macrophages in Breast Cancer and Pancreatic Neuroendocrine Tumors.

Mol Cancer Ther 2017 11 24;16(11):2486-2501. Epub 2017 Aug 24.

Department of Anatomy & Structural Biology, Albert Einstein College of Medicine, New York, New York.

Tumor-infiltrating myeloid cells promote tumor progression by mediating angiogenesis, tumor cell intravasation, and metastasis, which can offset the effects of chemotherapy, radiation, and antiangiogenic therapy. Here, we show that the kinase switch control inhibitor rebastinib inhibits Tie2, a tyrosine kinase receptor expressed on endothelial cells and protumoral Tie2-expressing macrophages in mouse models of metastatic cancer. Rebastinib reduces tumor growth and metastasis in an orthotopic mouse model of metastatic mammary carcinoma through reduction of Tie2 myeloid cell infiltration, antiangiogenic effects, and blockade of tumor cell intravasation mediated by perivascular Tie2/Vegf-A macrophages in the tumor microenvironment of metastasis (TMEM). The antitumor effects of rebastinib enhance the efficacy of microtubule inhibiting chemotherapeutic agents, either eribulin or paclitaxel, by reducing tumor volume, metastasis, and improving overall survival. Rebastinib inhibition of angiopoietin/Tie2 signaling impairs multiple pathways in tumor progression mediated by protumoral Tie2 macrophages, including TMEM-dependent dissemination and angiopoietin/Tie2-dependent angiogenesis. Rebastinib is a promising therapy for achieving Tie2 inhibition in cancer patients. .
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http://dx.doi.org/10.1158/1535-7163.MCT-17-0241DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5669998PMC
November 2017

Preclinical studies for a phase 1 clinical trial of autologous hematopoietic stem cell gene therapy for sickle cell disease.

Cytotherapy 2017 09 18;19(9):1096-1112. Epub 2017 Jul 18.

Department of Microbiology, Immunology and Molecular Genetics and the Eli & Edythe Broad Stem Cell Research Center, University of California, Los Angeles, California, USA. Electronic address:

Background Aims: Gene therapy by autologous hematopoietic stem cell transplantation (HSCT) represents a new approach to treat sickle cell disease (SCD). Optimization of the manufacture, characterization and testing of the transduced hematopoietic stem cell final cell product (FCP), as well as an in depth in vivo toxicology study, are critical for advancing this approach to clinical trials.

Methods: Data are shown to evaluate and establish the feasibility of isolating, transducing with the Lenti/β-FB vector and cryopreserving CD34 cells from human bone marrow (BM) at clinical scale. In vitro and in vivo characterization of the FCP was performed, showing that all the release criteria were successfully met. In vivo toxicology studies were conducted to evaluate potential toxicity of the Lenti/β-FB LV in the context of a murine BM transplant.

Results: Primary and secondary transplantation did not reveal any toxicity from the lentiviral vector. Additionally, vector integration site analysis of murine and human BM cells did not show any clonal skewing caused by insertion of the Lenti/β-FB vector in cells from primary and secondary transplanted mice.

Conclusions: We present here a complete protocol, thoroughly optimized to manufacture, characterize and establish safety of a FCP for gene therapy of SCD.
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http://dx.doi.org/10.1016/j.jcyt.2017.06.002DOI Listing
September 2017

Blast-Induced Tinnitus and Elevated Central Auditory and Limbic Activity in Rats: A Manganese-Enhanced MRI and Behavioral Study.

Sci Rep 2017 07 7;7(1):4852. Epub 2017 Jul 7.

Department of Otolaryngology and Head and Neck Surgery, Wayne State University School of Medicine, Detroit, MI, 48201, USA.

Blast-induced tinitus is the number one service-connected disability that currently affects military personnel and veterans. To elucidate its underlying mechanisms, we subjected 13 Sprague Dawley adult rats to unilateral 14 psi blast exposure to induce tinnitus and measured auditory and limbic brain activity using manganese-enhanced MRI (MEMRI). Tinnitus was evaluated with a gap detection acoustic startle reflex paradigm, while hearing status was assessed with prepulse inhibition (PPI) and auditory brainstem responses (ABRs). Both anxiety and cognitive functioning were assessed using elevated plus maze and Morris water maze, respectively. Five weeks after blast exposure, 8 of the 13 blasted rats exhibited chronic tinnitus. While acoustic PPI remained intact and ABR thresholds recovered, the ABR wave P1-N1 amplitude reduction persisted in all blast-exposed rats. No differences in spatial cognition were observed, but blasted rats as a whole exhibited increased anxiety. MEMRI data revealed a bilateral increase in activity along the auditory pathway and in certain limbic regions of rats with tinnitus compared to age-matched controls. Taken together, our data suggest that while blast-induced tinnitus may play a role in auditory and limbic hyperactivity, the non-auditory effects of blast and potential traumatic brain injury may also exert an effect.
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http://dx.doi.org/10.1038/s41598-017-04941-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5501813PMC
July 2017

Disparities in access to pediatric hearing health care.

Curr Opin Otolaryngol Head Neck Surg 2017 Oct;25(5):359-364

Department of Otolaryngology - Head and Neck Surgery, University of Kentucky Medical Center, Lexington, Kentucky, USA.

Purpose Of Review: There are significant disparities in care facing children with hearing loss. The objective of this review is to assess the current disparities in pediatric hearing healthcare delivery, describe the barriers of efficient and effective pediatric hearing health care, and explore the innovations to improve pediatric hearing healthcare delivery.

Recent Findings: Children with hearing loss from certain geographic regions or ethnic background are significantly delayed in diagnosis and treatment. Multiple patient characteristics (presentation of hearing loss), parental factors (insurance status, socioeconomic status, educational status, and travel distance to providers), and provider barriers (specialist shortage and primary care provider challenges) prevent the delivery of timely hearing health care. Advances, such as improved screening programs and the expansion of care through remote services, may help to ameliorate these disparities.

Summary: Timely identification and treatment of pediatric hearing loss is critical to prevent lifelong language complications. Children from vulnerable populations, such as rural residents, face significant disparities in care. Careful assessment of these barriers and implementation of culturally acceptable interventions are paramount to maximize communication outcomes of children with hearing loss.
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http://dx.doi.org/10.1097/MOO.0000000000000388DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5973811PMC
October 2017

Otolaryngology consultation tracheostomies and complex patient population.

Am J Otolaryngol 2017 Sep - Oct;38(5):551-555. Epub 2017 Jun 17.

Department of Otolaryngology, University of Kentucky Medical Center, 800 Rose St, C-236, Lexington, KY 40536, United States. Electronic address:

Purpose: To assess for the differences in patients undergoing tracheostomy by the otolaryngology consult service versus other specialties.

Materials And Methods: A series of 1035 tracheostomies performed at our institution from January 2013 through November 2015 was retrospectively reviewed. Patient-related factors that contribute to procedural difficulty were reviewed.

Results: 805 consecutive tracheostomies were included. Otolaryngology performed 176/805 (21.8%) tracheostomies as a consulting service. Morbidly obese patients were three times as likely to be referred to otolaryngology as other services (adjusted OR: 3.23; 95% CI: 2.21-4.72). Mean BMI was 36.38kg/m for Consults vs. 28.69kg/m for Others and morbidly obese patients had a mean BMI of 49.84kg/m vs. 42.68kg/m for Consults and Others respectively (p<0.001). Patients with upper airway compromise (8.5% of Consults vs. 1.6% for Others) had 5.5 times higher odds to be performed by otolaryngology (adjusted OR: 5.46; 95% CI: 2.24-13.28). Otolaryngology performed 81.8% of awake tracheostomies (n=9/11). There were significantly higher proportions of patients with diabetes, renal, pulmonary and cardiovascular disease in the Consults groups vs. Others (p<0.05).

Conclusions: More complex tracheostomies are being referred to and performed by otolaryngology at our institution. Difficult and challenging tracheostomies seem to be the "standard" for otolaryngologists.
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http://dx.doi.org/10.1016/j.amjoto.2017.05.009DOI Listing
June 2018

Adherence in the Cancer Care Setting: a Systematic Review of Patient Navigation to Traverse Barriers.

J Cancer Educ 2018 12;33(6):1222-1229

College of Medicine, University of Kentucky, Lexington, KY, USA.

Patient navigation is an evidence-based intervention involving trained healthcare workers who assist patients in assessing and mitigating personal and environmental factors to promote healthy behaviors. The purpose of this research is to systematically assess the efficacy of patient navigation and similar programs to improve diagnosis and treatment of diseases affecting medically underserved populations. A systematic review was performed by searching PubMed, MEDLINE, PsychINFO, and CINAHL to identify potential studies. Eligible studies were those containing original peer-reviewed research reports in English on patient navigation, community health workers, vulnerable and underserved populations, and healthcare disparity. Specific outcomes regarding patient navigator including the effect of the intervention on definitive diagnosis and effect on initiation of treatment were extracted from each study. The search produced 1428 articles, and 16 were included for review. All studies involved patient navigation in the field of oncology in underserved populations. Timing of initial contact with a patient navigator after diagnostic or screening testing is correlated to the effectiveness of the navigator intervention. The majority of the studies reported significantly shorter time intervals to diagnosis and to treatment with patient navigation. Patient navigation expedites oncologic diagnosis and treatment of patients in underserved populations. This intervention is more efficacious when utilized shortly after screening or diagnostic testing.
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http://dx.doi.org/10.1007/s13187-017-1235-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5711635PMC
December 2018

Aquatic microfauna alter larval food resources and affect development and biomass of West Nile and Saint Louis encephalitis vector (Diptera: Culicidae).

Ecol Evol 2017 05 9;7(10):3507-3519. Epub 2017 Apr 9.

Florida Medical Entomology Laboratory University of Florida/IFAS Vero Beach FL USA.

Ciliate protists and rotifers are ubiquitous in aquatic habitats and can comprise a significant portion of the microbial food resources available to larval mosquitoes, often showing substantial declines in abundance in the presence of mosquito larvae. This top-down regulation of protists is reported to be strong for mosquitoes inhabiting small aquatic containers such as pitcher plants or tree holes, but the nature of these interactions with larval mosquitoes developing in other aquatic habitats is poorly understood. We examined the effects of these two microbial groups on lower trophic level microbial food resources, such as bacteria, small flagellates, and organic particles, in the water column, and on larval development and adult production. In three independent laboratory experiments using two microeukaryote species (one ciliate protist and one rotifer) acquired from field larval mosquito habitats and cultured in the laboratory, we determined the effects of larval grazing on water column microbial dynamics, while simultaneously monitoring larval growth and development. The results revealed previously unknown interactions that were different from the top-down regulation of microbial groups by mosquito larvae in other systems. Both ciliates and rotifers, singly or in combination, altered other microbial populations and inhibited mosquito growth. It is likely that these microeukaryotes, instead of serving as food resources, competed with early instar mosquito larvae for microbes such as small flagellates and bacteria in a density-dependent manner. These findings help our understanding of the basic larval biology of mosquitoes, variation in mosquito production among various larval habitats, and may have implications for existing vector control strategies and for developing novel microbial-based control methods.
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http://dx.doi.org/10.1002/ece3.2947DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5433994PMC
May 2017
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