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Modeling. J Aerosol Med Pulm Drug Deliv 2024; 37:41-49. [PMID: 38052057 DOI: 10.1089/jamp.2023.29100.nam] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023] Open
Abstract
Modeling is coming to the fore as it is now widely accepted and indeed expected during drug discovery and development. Modeling integrates knowledge, increases understanding and provides the ability to predict an outcome either before it occurs or when it is not possible to measure. This makes modeling an attractive option for inhaled drugs as it is not possible to routinely measure what is occurring to the drug (pharmacokinetics) and what effect the drug is having (pharmacodynamics) at local microscopic sites of such a diverse and complex organ as the lung. Many pieces of information (data and knowledge) exist like the pieces of a jigsaw puzzle and modeling brings the pieces together in a scientific and mechanistically coherent manner to increase understanding of both the efficacy and safety of inhaled drugs.
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CYP2C8, CYP2C9, and CYP2C19 Characterization Using Next-Generation Sequencing and Haplotype Analysis: A GeT-RM Collaborative Project. J Mol Diagn 2022; 24:337-350. [PMID: 35134542 PMCID: PMC9069873 DOI: 10.1016/j.jmoldx.2021.12.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/09/2021] [Accepted: 12/28/2021] [Indexed: 01/13/2023] Open
Abstract
Pharmacogenetic tests typically target selected sequence variants to identify haplotypes that are often defined by star (∗) allele nomenclature. Due to their design, these targeted genotyping assays are unable to detect novel variants that may change the function of the gene product and thereby affect phenotype prediction and patient care. In the current study, 137 DNA samples that were previously characterized by the Genetic Testing Reference Material (GeT-RM) program using a variety of targeted genotyping methods were recharacterized using targeted and whole genome sequencing analysis. Sequence data were analyzed using three genotype calling tools to identify star allele diplotypes for CYP2C8, CYP2C9, and CYP2C19. The genotype calls from next-generation sequencing (NGS) correlated well to those previously reported, except when novel alleles were present in a sample. Six novel alleles and 38 novel suballeles were identified in the three genes due to identification of variants not covered by targeted genotyping assays. In addition, several ambiguous genotype calls from a previous study were resolved using the NGS and/or long-read NGS data. Diplotype calls were mostly consistent between the calling algorithms, although several discrepancies were noted. This study highlights the utility of NGS for pharmacogenetic testing and demonstrates that there are many novel alleles that are yet to be discovered, even in highly characterized genes such as CYP2C9 and CYP2C19.
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Physiologically Based Pharmacokinetic Modelling of Inhaled Nemiralisib: Mechanistic Components for Pulmonary Absorption, Systemic Distribution, and Oral Absorption. Clin Pharmacokinet 2021; 61:281-293. [PMID: 34458976 PMCID: PMC8813803 DOI: 10.1007/s40262-021-01066-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2021] [Indexed: 11/02/2022]
Abstract
BACKGROUND AND OBJECTIVES Physiologically based pharmacokinetic (PBPK) modelling has evolved to accommodate different routes of drug administration and enables prediction of drug concentrations in tissues as well as plasma. The inhalation route of administration has proven successful in treating respiratory diseases but can also be used for rapid systemic delivery, holding great promise for treatment of diseases requiring systemic exposure. The objective of this work was to develop a PBPK model that predicts plasma and tissue concentrations following inhalation administration of the PI3Kδ inhibitor nemiralisib. METHODS A PBPK model was built in GastroPlus® that includes a complete mechanistic description of pulmonary absorption, systemic distribution and oral absorption following inhalation administration of nemiralisib. The availability of clinical data obtained after intravenous, oral and inhalation administration enabled validation of the model with observed data and accurate assessment of pulmonary drug absorption. The PBPK model described in this study incorporates novel use of key parameters such as lung systemic absorption rate constants derived from human physiological lung blood flows, and implementation of the specific permeability-surface area product per millilitre of tissue cell volume (SpecPStc) to predict tissue distribution. RESULTS The inhaled PBPK model was verified using plasma and bronchoalveolar lavage fluid concentration data obtained in human subjects. Prediction of tissue concentrations using the permeability-limited systemic disposition tissue model was further validated using tissue concentration data obtained in the rat following intravenous infusion administration to steady state. CONCLUSIONS Fully mechanistic inhaled PBPK models such as the model described herein could be applied for cross molecule assessments with respect to lung retention and systemic exposure, both in terms of pharmacology and toxicology, and may facilitate clinical indication selection.
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Pharmacogene Variation Consortium: A Global Resource and Repository for Pharmacogene Variation. Clin Pharmacol Ther 2021; 110:542-545. [PMID: 34091888 DOI: 10.1002/cpt.2321] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 05/17/2021] [Indexed: 12/14/2022]
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PharmVar GeneFocus: CYP2B6. Clin Pharmacol Ther 2021; 110:82-97. [PMID: 33448339 DOI: 10.1002/cpt.2166] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 12/21/2020] [Indexed: 12/12/2022]
Abstract
The Pharmacogene Variation Consortium (PharmVar) catalogs star (*) allele nomenclature for the polymorphic human CYP2B6 gene. Genetic variation within the CYP2B6 gene locus impacts the metabolism or bioactivation of clinically important drugs. Of particular importance are efficacy and safety concerns regarding: efavirenz, which is used for the treatment of HIV type-1 infection; methadone, a mainstay in the treatment of opioid use disorder and as an analgesic; ketamine, used as an antidepressant and analgesic; and bupropion, which is prescribed to treat depression and for smoking cessation. This GeneFocus provides a comprehensive overview and summary of CYP2B6 and describes how haplotype information catalogued by PharmVar is utilized by the Pharmacogenomics Knowledgebase (PharmGKB) and the Clinical Pharmacogenetics Implementation Consortium (CPIC).
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Physiologically Based Pharmacokinetic Modelling for First-In-Human Predictions: An Updated Model Building Strategy Illustrated with Challenging Industry Case Studies. Clin Pharmacokinet 2020; 58:727-746. [PMID: 30729397 DOI: 10.1007/s40262-019-00741-9] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Physiologically based pharmacokinetic modelling is well established in the pharmaceutical industry and is accepted by regulatory agencies for the prediction of drug-drug interactions. However, physiologically based pharmacokinetic modelling is valuable to address a much wider range of pharmaceutical applications, and new regulatory impact is expected as its full power is leveraged. As one example, physiologically based pharmacokinetic modelling is already routinely used during drug discovery for in-vitro to in-vivo translation and pharmacokinetic modelling in preclinical species, and this leads to the application of verified models for first-in-human pharmacokinetic predictions. A consistent cross-industry strategy in this application area would increase confidence in the approach and facilitate further learning. With this in mind, this article aims to enhance a previously published first-in-human physiologically based pharmacokinetic model-building strategy. Based on the experience of scientists from multiple companies participating in the GastroPlus™ User Group Steering Committee, new Absorption, Distribution, Metabolism and Excretion knowledge is integrated and decision trees proposed for each essential component of a first-in-human prediction. We have reviewed many relevant scientific publications to identify new findings and highlight gaps that need to be addressed. Finally, four industry case studies for more challenging compounds illustrate and highlight key components of the strategy.
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Long-Distance Phasing of a Tentative "Enhancer" Single-Nucleotide Polymorphism With CYP2D6 Star Allele Definitions. Front Pharmacol 2020; 11:486. [PMID: 32457600 PMCID: PMC7226225 DOI: 10.3389/fphar.2020.00486] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 03/27/2020] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND The CYP2D6 gene locus has been extensively studied over decades, yet a portion of variability in CYP2D6 activity cannot be explained by known sequence variations within the gene, copy number variation, or structural rearrangements. It was proposed that rs5758550, located 116 kb downstream of the CYP2D6 gene locus, increases gene expression and thus contributes to variability in CYP2D6 activity. This finding has, however, not been validated. The purpose of the study was to address a major technological barrier, i.e., experimentally linking rs5758550, also referred to as the "enhancer" single-nucleotide polymorphism (SNP), to CYP2D6 haplotypes >100 kb away. To overcome this challenge is essential to ultimately determine the contribution of the "enhancer" SNP to interindividual variability in CYP2D6 activity. METHODS A large ethnically mixed population sample (n=3,162) was computationally phased to determine linkage between the "enhancer" SNP and CYP2D6 haplotypes (or star alleles). To experimentally validate predicted linkages, DropPhase2D6, a digital droplet PCR (ddPCR)-based method was developed. 10X Genomics Linked-Reads were utilized as a proof of concept. RESULTS Phasing predicted that the "enhancer" SNP can occur on numerous CYP2D6 haplotypes including CYP2D6*1, *2, *5, and *41 and suggested that linkage is incomplete, i.e., a portion of these alleles do not have the "enhancer" SNP. Phasing also revealed differences among the European and African ancestry data sets regarding the proportion of alleles with and without the "enhancer" SNP. DropPhase2D6 was utilized to confirm or refute the predicted "enhancer" SNP location for individual samples, e.g., of n=3 samples genotyped as *1/*41, rs5758550 was on the *41 allele of two samples and on the *1 allele of one sample. Our findings highlight that the location of the "enhancer" SNP must not be assigned by "default." Furthermore, linkage between the "enhancer" SNP and CYP2D6 star allele haplotypes was confirmed with 10X Genomics technology. CONCLUSIONS Since the "enhancer" SNP can be present on a portion of normal, decreased, or no function alleles, the phase of the "enhancer" SNP must be considered when investigating the impact of the "enhancer" SNP on CYP2D6 activity.
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P191 - The CYP2D6 ‘enhancer’ SNP: Long-range linkage analysis and impact on activity in human liver tissue. Drug Metab Pharmacokinet 2020. [DOI: 10.1016/j.dmpk.2020.04.192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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PharmVar and the Landscape of Pharmacogenetic Resources. Clin Pharmacol Ther 2020; 107:43-46. [PMID: 31758698 PMCID: PMC6925620 DOI: 10.1002/cpt.1654] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 08/27/2019] [Indexed: 11/08/2022]
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The Evolution of PharmVar. Clin Pharmacol Ther 2018; 105:29-32. [PMID: 30536702 PMCID: PMC6312487 DOI: 10.1002/cpt.1275] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 10/25/2018] [Indexed: 11/06/2022]
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Pharmacogene Variation Consortium Gene Introduction: NUDT15. Clin Pharmacol Ther 2018; 105:1091-1094. [PMID: 30515762 PMCID: PMC6465081 DOI: 10.1002/cpt.1268] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 09/26/2018] [Indexed: 12/22/2022]
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Correction: Whole exome sequencing reveals HSPA1L as a genetic risk factor for spontaneous preterm birth. PLoS Genet 2018; 14:e1007673. [PMID: 30212495 PMCID: PMC6136685 DOI: 10.1371/journal.pgen.1007673] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Whole exome sequencing reveals HSPA1L as a genetic risk factor for spontaneous preterm birth. PLoS Genet 2018; 14:e1007394. [PMID: 30001343 PMCID: PMC6042692 DOI: 10.1371/journal.pgen.1007394] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 05/03/2018] [Indexed: 11/18/2022] Open
Abstract
Preterm birth is a leading cause of morbidity and mortality in infants. Genetic and environmental factors play a role in the susceptibility to preterm birth, but despite many investigations, the genetic basis for preterm birth remain largely unknown. Our objective was to identify rare, possibly damaging, nucleotide variants in mothers from families with recurrent spontaneous preterm births (SPTB). DNA samples from 17 Finnish mothers who delivered at least one infant preterm were subjected to whole exome sequencing. All mothers were of northern Finnish origin and were from seven multiplex families. Additional replication samples of European origin consisted of 93 Danish sister pairs (and two sister triads), all with a history of a preterm delivery. Rare exonic variants (frequency <1%) were analyzed to identify genes and pathways likely to affect SPTB susceptibility. We identified rare, possibly damaging, variants in genes that were common to multiple affected individuals. The glucocorticoid receptor signaling pathway was the most significant (p<1.7e-8) with genes containing these variants in a subgroup of ten Finnish mothers, each having had 2-4 SPTBs. This pathway was replicated among the Danish sister pairs. A gene in this pathway, heat shock protein family A (Hsp70) member 1 like (HSPA1L), contains two likely damaging missense alleles that were found in four different Finnish families. One of the variants (rs34620296) had a higher frequency in cases compared to controls (0.0025 vs. 0.0010, p = 0.002) in a large preterm birth genome-wide association study (GWAS) consisting of mothers of general European ancestry. Sister pairs in replication samples also shared rare, likely damaging HSPA1L variants. Furthermore, in silico analysis predicted an additional phosphorylation site generated by rs34620296 that could potentially affect chaperone activity or HSPA1L protein stability. Finally, in vitro functional experiment showed a link between HSPA1L activity and decidualization. In conclusion, rare, likely damaging, variants in HSPA1L were observed in multiple families with recurrent SPTB.
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The Pharmacogene Variation (PharmVar) Consortium: Incorporation of the Human Cytochrome P450 (CYP) Allele Nomenclature Database. Clin Pharmacol Ther 2018; 103:399-401. [PMID: 29134625 PMCID: PMC5836850 DOI: 10.1002/cpt.910] [Citation(s) in RCA: 274] [Impact Index Per Article: 45.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 10/02/2017] [Accepted: 10/11/2017] [Indexed: 01/08/2023]
Abstract
The Human Cytochrome P450 (CYP) Allele Nomenclature Database, a critical resource for the pharmacogenetics and genomics communities, has transitioned to the Pharmacogene Variation (PharmVar) Consortium. In this report we provide a summary of the current database, provide an overview of the PharmVar consortium, and highlight the PharmVar database which will serve as the new home for pharmacogene nomenclature.
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The NSIGHT1-randomized controlled trial: rapid whole-genome sequencing for accelerated etiologic diagnosis in critically ill infants. NPJ Genom Med 2018; 3:6. [PMID: 29449963 PMCID: PMC5807510 DOI: 10.1038/s41525-018-0045-8] [Citation(s) in RCA: 135] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 01/02/2018] [Accepted: 01/12/2018] [Indexed: 12/31/2022] Open
Abstract
Genetic disorders are a leading cause of morbidity and mortality in infants in neonatal and pediatric intensive care units (NICU/PICU). While genomic sequencing is useful for genetic disease diagnosis, results are usually reported too late to guide inpatient management. We performed an investigator-initiated, partially blinded, pragmatic, randomized, controlled trial to test the hypothesis that rapid whole-genome sequencing (rWGS) increased the proportion of NICU/PICU infants receiving a genetic diagnosis within 28 days. The participants were families with infants aged <4 months in a regional NICU and PICU, with illnesses of unknown etiology. The intervention was trio rWGS. Enrollment from October 2014 to June 2016, and follow-up until November 2016. Of all, 26 female infants, 37 male infants, and 2 infants of undetermined sex were randomized to receive rWGS plus standard genetic tests (n = 32, cases) or standard genetic tests alone (n = 33, controls). The study was terminated early due to loss of equipoise: 73% (24) controls received genomic sequencing as standard tests, and 15% (five) controls underwent compassionate cross-over to receive rWGS. Nevertheless, intention to treat analysis showed the rate of genetic diagnosis within 28 days of enrollment (the primary end-point) to be higher in cases (31%, 10 of 32) than controls (3%, 1 of 33; difference, 28% [95% CI, 10-46%]; p = 0.003). Among infants enrolled in the first 25 days of life, the rate of neonatal diagnosis was higher in cases (32%, 7 of 22) than controls (0%, 0 of 23; difference, 32% [95% CI, 11-53%];p = 0.004). Median age at diagnosis (25 days [range 14-90] in cases vs. 130 days [range 37-451] in controls) and median time to diagnosis (13 days [range 1-84] in cases, vs. 107 days [range 21-429] in controls) were significantly less in cases than controls (p = 0.04). In conclusion, rWGS increased the proportion of NICU/PICU infants who received timely diagnoses of genetic diseases.
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In vivo characterization of CYP2D6*12, *29 and *84 using dextromethorphan as a probe drug: a case report. Pharmacogenomics 2017; 18:427-431. [PMID: 28290770 DOI: 10.2217/pgs-2016-0192] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
CYP2D6*84 was first described in a Black South African subject, however, its function remains unknown. Astrolabe, a probabilistic scoring tool developed in our laboratory to call genotypes from whole genome sequence, identified CYP2D6*84 in a trio. The father presented with intermediate metabolism when challenged with the CYP2D6 probe drug dextromethorphan (DM/dextrorphan [DX] = 0.0839). Since his second allele, CYP2D6*12, is nonfunctional, the observed activity is derived by CYP2D6*84. This finding suggests that the allele's hallmark P267H causes decreased activity toward DM and that this allele should receive a value of 0.5 for Activity Score calculations. The mother's DM/DX of 0.0543 was consistent with the decreased activity classification of CYP2D6*29. The child, a critically ill neonate, was not phenotyped, but predicted to be a normal metabolizer.
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Erratum: Constellation: a tool for rapid, automated phenotype assignment of a highly polymorphic pharmacogene, CYP2D6, from whole-genome sequences. NPJ Genom Med 2017; 2:16039. [PMID: 29266105 PMCID: PMC5685321 DOI: 10.1038/npjgenmed.2016.39] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Clinical detection of deletion structural variants in whole-genome sequences. NPJ Genom Med 2016; 1:16026. [PMID: 29263817 PMCID: PMC5685307 DOI: 10.1038/npjgenmed.2016.26] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Revised: 06/22/2016] [Accepted: 06/22/2016] [Indexed: 12/13/2022] Open
Abstract
Optimal management of acutely ill infants with monogenetic diseases requires rapid identification of causative haplotypes. Whole-genome sequencing (WGS) has been shown to identify pathogenic nucleotide variants in such infants. Deletion structural variants (DSVs, >50 nt) are implicated in many genetic diseases, and tools have been designed to identify DSVs using short-read WGS. Optimisation and integration of these tools into a WGS pipeline could improve diagnostic sensitivity and specificity of WGS. In addition, it may improve turnaround time when compared with current CNV assays, enhancing utility in acute settings. Here we describe DSV detection methods for use in WGS for rapid diagnosis in acutely ill infants: SKALD (Screening Konsensus and Annotation of Large Deletions) combines calls from two tools (Breakdancer and GenomeStrip) with calibrated filters and clinical interpretation rules. In four WGS runs, the average analytic precision (positive predictive value) of SKALD was 78%, and recall (sensitivity) was 27%, when compared with validated reference DSV calls. When retrospectively applied to a cohort of 36 families with acutely ill infants SKALD identified causative DSVs in two. The first was heterozygous deletion of exons 1–3 of MMP21 in trans with a heterozygous frame-shift deletion in two siblings with transposition of the great arteries and heterotaxy. In a newborn female with dysmorphic features, ventricular septal defect and persistent pulmonary hypertension, SKALD identified the breakpoints of a heterozygous, de novo 1p36.32p36.13 deletion. In summary, consensus DSV calling, implemented in an 8-h computational pipeline with parameterised filtering, has the potential to increase the diagnostic yield of WGS in acutely ill neonates and discover novel disease genes.
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MMP21 is mutated in human heterotaxy and is required for normal left-right asymmetry in vertebrates. Nat Genet 2015; 47:1260-3. [PMID: 26437028 PMCID: PMC5620017 DOI: 10.1038/ng.3376] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 07/10/2015] [Indexed: 12/26/2022]
Abstract
Heterotaxy results from a failure to establish normal left-right asymmetry early in embryonic development. By whole-exome sequencing, whole-genome sequencing and high-throughput cohort resequencing, we identified recessive mutations in MMP21 (encoding matrix metallopeptidase 21) in nine index cases with heterotaxy. In addition, Mmp21-mutant mice and mmp21-morphant zebrafish displayed heterotaxy and abnormal cardiac looping, respectively, suggesting a new role for extracellular matrix remodeling in the establishment of laterality in vertebrates.
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A 26-hour system of highly sensitive whole genome sequencing for emergency management of genetic diseases. Genome Med 2015; 7:100. [PMID: 26419432 PMCID: PMC4588251 DOI: 10.1186/s13073-015-0221-8] [Citation(s) in RCA: 174] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 09/10/2015] [Indexed: 12/14/2022] Open
Abstract
While the cost of whole genome sequencing (WGS) is approaching the realm of routine medical tests, it remains too tardy to help guide the management of many acute medical conditions. Rapid WGS is imperative in light of growing evidence of its utility in acute care, such as in diagnosis of genetic diseases in very ill infants, and genotype-guided choice of chemotherapy at cancer relapse. In such situations, delayed, empiric, or phenotype-based clinical decisions may meet with substantial morbidity or mortality. We previously described a rapid WGS method, STATseq, with a sensitivity of >96 % for nucleotide variants that allowed a provisional diagnosis of a genetic disease in 50 h. Here improvements in sequencing run time, read alignment, and variant calling are described that enable 26-h time to provisional molecular diagnosis with >99.5 % sensitivity and specificity of genotypes. STATseq appears to be an appropriate strategy for acutely ill patients with potentially actionable genetic diseases.
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Effectiveness of exome and genome sequencing guided by acuity of illness for diagnosis of neurodevelopmental disorders. Sci Transl Med 2015; 6:265ra168. [PMID: 25473036 DOI: 10.1126/scitranslmed.3010076] [Citation(s) in RCA: 384] [Impact Index Per Article: 42.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Neurodevelopmental disorders (NDDs) affect more than 3% of children and are attributable to single-gene mutations at more than 1000 loci. Traditional methods yield molecular diagnoses in less than one-half of children with NDD. Whole-genome sequencing (WGS) and whole-exome sequencing (WES) can enable diagnosis of NDD, but their clinical and cost-effectiveness are unknown. One hundred families with 119 children affected by NDD received diagnostic WGS and/or WES of parent-child trios, wherein the sequencing approach was guided by acuity of illness. Forty-five percent received molecular diagnoses. An accelerated sequencing modality, rapid WGS, yielded diagnoses in 73% of families with acutely ill children (11 of 15). Forty percent of families with children with nonacute NDD, followed in ambulatory care clinics (34 of 85), received diagnoses: 33 by WES and 1 by staged WES then WGS. The cost of prior negative tests in the nonacute patients was $19,100 per family, suggesting sequencing to be cost-effective at up to $7640 per family. A change in clinical care or impression of the pathophysiology was reported in 49% of newly diagnosed families. If WES or WGS had been performed at symptom onset, genomic diagnoses may have been made 77 months earlier than occurred in this study. It is suggested that initial diagnostic evaluation of children with NDD should include trio WGS or WES, with extension of accelerated sequencing modalities to high-acuity patients.
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Alström Syndrome: Mutation Spectrum of ALMS1. Hum Mutat 2015; 36:660-8. [PMID: 25846608 PMCID: PMC4475486 DOI: 10.1002/humu.22796] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 03/25/2015] [Accepted: 03/29/2015] [Indexed: 12/24/2022]
Abstract
Alström Syndrome (ALMS), a recessive, monogenic ciliopathy caused by mutations in ALMS1, is typically characterized by multisystem involvement including early cone-rod retinal dystrophy and blindness, hearing loss, childhood obesity, type 2 diabetes mellitus, cardiomyopathy, fibrosis, and multiple organ failure. The precise function of ALMS1 remains elusive, but roles in endosomal and ciliary transport and cell cycle regulation have been shown. The aim of our study was to further define the spectrum of ALMS1 mutations in patients with clinical features of ALMS. Mutational analysis in a world-wide cohort of 204 families identified 109 novel mutations, extending the number of known ALMS1 mutations to 239 and highlighting the allelic heterogeneity of this disorder. This study represents the most comprehensive mutation analysis in patients with ALMS, identifying the largest number of novel mutations in a single study worldwide. Here, we also provide an overview of all ALMS1 mutations identified to date.
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Whole-genome sequencing for identification of Mendelian disorders in critically ill infants: a retrospective analysis of diagnostic and clinical findings. THE LANCET RESPIRATORY MEDICINE 2015; 3:377-87. [PMID: 25937001 DOI: 10.1016/s2213-2600(15)00139-3] [Citation(s) in RCA: 265] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 03/30/2015] [Accepted: 04/01/2015] [Indexed: 12/28/2022]
Abstract
BACKGROUND Genetic disorders and congenital anomalies are the leading causes of infant mortality. Diagnosis of most genetic diseases in neonatal and paediatric intensive care units (NICU and PICU) is not sufficiently timely to guide acute clinical management. We used rapid whole-genome sequencing (STATseq) in a level 4 NICU and PICU to assess the rate and types of molecular diagnoses, and the prevalence, types, and effect of diagnoses that are likely to change medical management in critically ill infants. METHODS We did a retrospective comparison of STATseq and standard genetic testing in a case series from the NICU and PICU of a large children's hospital between Nov 11, 2011, and Oct 1, 2014. The participants were families with an infant younger than 4 months with an acute illness of suspected genetic cause. The intervention was STATseq of trios (both parents and their affected infant). The main measures were the diagnostic rate, time to diagnosis, and rate of change in management after standard genetic testing and STATseq. FINDINGS 20 (57%) of 35 infants were diagnosed with a genetic disease by use of STATseq and three (9%) of 32 by use of standard genetic testing (p=0·0002). Median time to genome analysis was 5 days (range 3-153) and median time to STATseq report was 23 days (5-912). 13 (65%) of 20 STATseq diagnoses were associated with de-novo mutations. Acute clinical usefulness was noted in 13 (65%) of 20 infants with a STATseq diagnosis, four (20%) had diagnoses with strongly favourable effects on management, and six (30%) were started on palliative care. 120-day mortality was 57% (12 of 21) in infants with a genetic diagnosis. INTERPRETATION In selected acutely ill infants, STATseq had a high rate of diagnosis of genetic disorders. Most diagnoses altered the management of infants in the NICU or PICU. The very high infant mortality rate indicates a substantial need for rapid genomic diagnoses to be allied with a novel framework for precision medicine for infants in NICU and PICU who are diagnosed with genetic diseases to improve outcomes. FUNDING Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Human Genome Research Institute, and National Center for Advancing Translational Sciences.
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An integrated transcriptome and expressed variant analysis of sepsis survival and death. Genome Med 2014; 6:111. [PMID: 25538794 PMCID: PMC4274761 DOI: 10.1186/s13073-014-0111-5] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 11/14/2014] [Indexed: 12/13/2022] Open
Abstract
Background Sepsis, a leading cause of morbidity and mortality, is not a homogeneous disease but rather a syndrome encompassing many heterogeneous pathophysiologies. Patient factors including genetics predispose to poor outcomes, though current clinical characterizations fail to identify those at greatest risk of progression and mortality. Methods The Community Acquired Pneumonia and Sepsis Outcome Diagnostic study enrolled 1,152 subjects with suspected sepsis. We sequenced peripheral blood RNA of 129 representative subjects with systemic inflammatory response syndrome (SIRS) or sepsis (SIRS due to infection), including 78 sepsis survivors and 28 sepsis non-survivors who had previously undergone plasma proteomic and metabolomic profiling. Gene expression differences were identified between sepsis survivors, sepsis non-survivors, and SIRS followed by gene enrichment pathway analysis. Expressed sequence variants were identified followed by testing for association with sepsis outcomes. Results The expression of 338 genes differed between subjects with SIRS and those with sepsis, primarily reflecting immune activation in sepsis. Expression of 1,238 genes differed with sepsis outcome: non-survivors had lower expression of many immune function-related genes. Functional genetic variants associated with sepsis mortality were sought based on a common disease-rare variant hypothesis. VPS9D1, whose expression was increased in sepsis survivors, had a higher burden of missense variants in sepsis survivors. The presence of variants was associated with altered expression of 3,799 genes, primarily reflecting Golgi and endosome biology. Conclusions The activation of immune response-related genes seen in sepsis survivors was muted in sepsis non-survivors. The association of sepsis survival with a robust immune response and the presence of missense variants in VPS9D1 warrants replication and further functional studies. Trial registration ClinicalTrials.gov NCT00258869. Registered on 23 November 2005. Electronic supplementary material The online version of this article (doi:10.1186/s13073-014-0111-5) contains supplementary material, which is available to authorized users.
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Exposure of prepubertal beef bulls to cycling females does not enhance sexual development. Theriogenology 2014; 82:447-54. [PMID: 24888685 DOI: 10.1016/j.theriogenology.2014.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 04/30/2014] [Accepted: 05/01/2014] [Indexed: 10/25/2022]
Abstract
The objective of this study was to determine whether continuous, long-term, fenceline exposure of prepubertal beef bulls to cycling beef females reduced age at puberty and influenced the percentage of bulls that passed an initial breeding soundness examination (BSE). Bulls (Angus, n = 37; Simmental, n = 22; Hereford, n = 10; Simmental × Angus, n = 8) at an average age of 202 ± 21.5 days were given either continuous fenceline and visual exposure to cycling females (exposed, n = 41) or no exposure (control, n = 36). Estrus was induced in cycling beef females so at least three females were in standing estrus each week during the 182 days of exposure to bulls. Scrotal circumference (SC), body weight, and blood samples were collected every 28 days. When bulls had SC of 26 cm or more, semen samples were obtained monthly via electroejaculation until puberty was achieved (≥50 × 10(6) sperm/mL with at least 10% progressive motility). Behavioral observations were conducted twice monthly: once when females were in estrus and once during diestrus. Homosexual mounting, flehmen responses, and number of times near penned females were recorded for each observation period. Breeding soundness examinations were conducted when the average age of bulls was 364 ± 21.5 days. Normal sperm morphology of at least 70% and sperm motility of at least 30% were required to pass the BSE. Age, body weight, and SC at puberty did not differ between exposed and control bulls (320 ± 28 and 311 ± 29 days; 466.2 ± 12.2 and 437.7 ± 13.5 kg; and 34.4 ± 2.5 and 34.9 ± 2.5 cm, respectively). Percentage of bulls passing their initial BSE did not differ between treatments (exposed, 87.8%; control, 75.0%). Treatment, month, and female estrous stage interacted (P = 0.05) to affect the number of mount attempts and flehmen responses. Exposed bulls entered the cow area more times (P < 0.001) during estrus than diestrus in Months 1, 2, and 3. We concluded that bulls given continuous, long-term, fenceline exposure to cycling beef females do not have enhanced sexual development.
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De novo frameshift mutation in ASXL3 in a patient with global developmental delay, microcephaly, and craniofacial anomalies. BMC Med Genomics 2013; 6:32. [PMID: 24044690 PMCID: PMC3851682 DOI: 10.1186/1755-8794-6-32] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 09/11/2013] [Indexed: 12/23/2022] Open
Abstract
Background Currently, diagnosis of affected individuals with rare genetic disorders can be lengthy and costly, resulting in a diagnostic odyssey and in many patients a definitive molecular diagnosis is never achieved despite extensive clinical investigation. The recent advent and use of genomic medicine has resulted in a paradigm shift in the clinical molecular genetics of rare diseases and has provided insight into the causes of numerous rare genetic conditions. In particular, whole exome and genome sequencing of families has been particularly useful in discovering de novo germline mutations as the cause of both rare diseases and complex disorders. Case presentation We present a six year old, nonverbal African American female with microcephaly, autism, global developmental delay, and metopic craniosynostosis. Exome sequencing of the patient and her two parents revealed a heterozygous two base pair de novo deletion, c.1897_1898delCA, p.Gln633ValfsX13 in ASXL3, predicted to result in a frameshift at codon 633 with substitution of a valine for a glutamine and introduction of a premature stop codon. Conclusions We provide additional evidence that, truncating and frameshifting mutations in the ASXL3 gene are the cause of a newly recognized disorder characterized by severe global developmental delay, short stature, microcephaly, and craniofacial anomalies. Furthermore, we expand the knowledge about disease causing mutations and the genotype-phenotype relationships in ASXL3 and provide evidence that rare, nonsynonymous, damaging mutations are not associated with developmental delay or microcephaly.
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Abstract
Sepsis is a common cause of death, but outcomes in individual patients are difficult to predict. Elucidating the molecular processes that differ between sepsis patients who survive and those who die may permit more appropriate treatments to be deployed. We examined the clinical features and the plasma metabolome and proteome of patients with and without community-acquired sepsis, upon their arrival at hospital emergency departments and 24 hours later. The metabolomes and proteomes of patients at hospital admittance who would ultimately die differed markedly from those of patients who would survive. The different profiles of proteins and metabolites clustered into the following groups: fatty acid transport and β-oxidation, gluconeogenesis, and the citric acid cycle. They differed consistently among several sets of patients, and diverged more as death approached. In contrast, the metabolomes and proteomes of surviving patients with mild sepsis did not differ from survivors with severe sepsis or septic shock. An algorithm derived from clinical features together with measurements of five metabolites predicted patient survival. This algorithm may help to guide the treatment of individual patients with sepsis.
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Combined DOCK8 and CLEC7A mutations causing immunodeficiency in 3 brothers with diarrhea, eczema, and infections. J Allergy Clin Immunol 2013; 131:594-7.e1-3. [PMID: 23374272 DOI: 10.1016/j.jaci.2012.10.062] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2012] [Revised: 10/29/2012] [Accepted: 10/31/2012] [Indexed: 11/25/2022]
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Role of Nek2 on centrosome duplication and aneuploidy in breast cancer cells. Oncogene 2013; 33:2375-84. [PMID: 23708664 DOI: 10.1038/onc.2013.183] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 04/04/2013] [Accepted: 04/04/2013] [Indexed: 11/09/2022]
Abstract
Breast cancer is the most common solid tumor and the second most common cause of death in women. Despite a large body of literature and progress in breast cancer research, many molecular aspects of this complex disease are still poorly understood, hindering the design of specific and effective therapeutic strategies. To identify the molecules important in breast cancer progression and metastasis, we tested the in vivo effects of inhibiting the functions of various kinases and genes involved in the regulation/modulation of the cytoskeleton by downregulating them in mouse PyMT mammary tumor cells and human breast cancer cell lines. These kinases and cytoskeletal regulators were selected based on their prognostic values for breast cancer patient survival. PyMT tumor cells, in which a selected gene was stably knocked down were injected into the tail veins of mice, and the formation of tumors in the lungs was monitored. One of the several genes found to be important for tumor growth in the lungs was NIMA-related kinases 2 (Nek2), a cell cycle-related protein kinase. Furthermore, Nek2 was also important for tumor growth in the mammary fat pad. In various human breast cancer cell lines, Nek2 knockdown induced aneuploidy and cell cycle arrest that led to cell death. Significantly, the breast cancer cell line most sensitive to Nek2 depletion was of the triple negative breast cancer subtype. Our data indicate that Nek2 has a pivotal role in breast cancer growth at primary and secondary sites, and thus may be an attractive and novel therapeutic target for this disease.
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Diagnosis of mitochondrial disorders by concomitant next-generation sequencing of the exome and mitochondrial genome. Genomics 2013; 102:148-56. [PMID: 23631824 DOI: 10.1016/j.ygeno.2013.04.013] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 04/18/2013] [Accepted: 04/19/2013] [Indexed: 01/22/2023]
Abstract
Mitochondrial diseases are notoriously difficult to diagnose due to extreme locus and allelic heterogeneity, with both nuclear and mitochondrial genomes potentially liable. Using exome sequencing we demonstrate the ability to rapidly and cost effectively evaluate both the nuclear and mitochondrial genomes to obtain a molecular diagnosis for four patients with three distinct mitochondrial disorders. One patient was found to have Leigh syndrome due to a mutation in MT-ATP6, two affected siblings were discovered to be compound heterozygous for mutations in the NDUFV1 gene, which causes mitochondrial complex I deficiency, and one patient was found to have coenzyme Q10 deficiency due to compound heterozygous mutations in COQ2. In all cases conventional diagnostic testing failed to identify a molecular diagnosis. We suggest that additional studies should be conducted to evaluate exome sequencing as a primary diagnostic test for mitochondrial diseases, including those due to mtDNA mutations.
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Abstract P2-10-33: Mitotic Component of Grade Can Distinguish Breast Cancer Patients at Greatest Risk of Local Relapse. Cancer Res 2012. [DOI: 10.1158/0008-5472.sabcs12-p2-10-33] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: With the recent recognition of many different molecular subtypes of breast cancer a desire to more specifically categorize tumors to allow tailoring of treatment to individual patients has developed. This has largely involved the development of molecular tests rather than the re-examination of current pathologic criteria. We wanted to evaluate standard pathologic features to determine their ability to predict for local recurrence.
Materials and Methods: Slides were retrieved for review from 280 of 769 women who had participated in a trial of tamoxifen with or without breast irradiation between December 1992 and June 2000 and for whom outcome data up to 18 years was available. All women were 50 years of age or older at the time of enrollment and had T1 or T2 node negative breast cancer. The cases for which slides were obtained were representative of the whole group. The slides were reviewed by two breast pathologists (SJD and NAM). Several features were evaluated; modified Nottingham histologic grade and its components- degree of tubule formation, nuclear pleomorphism and mitotic count. Mitotic component of grade was calibrated to the microscopic field size used. The presence of lymphatic/vascular space invasion was also scored. A statistical analysis was performed to relate these pathologic features to local recurrence at up to 18 years.
Results: The strongest predictor of local recurrence was the mitotic component of the Nottingham histologic grade with 5.7% for mitotic score 1/3 (n = 200), 19.6% for mitotic score 2/3 (n = 37) and 19.8% for mitotic score 3/3 (n = 43)(Gray's p-value = 0.0021). Overall grade was also able to predict for local recurrence with 2.6% for Grade 1 (n = 49), 10.6% for Grade 2 (n = 162) and 17.9% for Grade 3 (n = 71)(Gray's p-value=0.026). However, neither architecture (0% vs. 9.5% vs. 9.8%, Gray's p-value=0.74) nor degree of nuclear pleomorphism (0% vs. 7.9% vs. 11.5%, Gray's p-value=0.37), the other components of histologic grade, showed a statistically significant difference for recurrence. The presence or absence of endothelial lined space invasion was also found to be not statistically different (9.3% vs. 13%, Gray's p-value=0.55).
Conclusion: Within this cohort of tamoxifen treated T1 and T2 breast cancer patients 50 years of age or older, mitotic index could stratify women into groups with high and low risk of recurrence. If validated this may be a useful way of allocating patients to different treatment groups. Additional validation studies are planned on similar groups of patients.
Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-10-33.
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Genome sequencing and mapping reveal loss of heterozygosity as a mechanism for rapid adaptation in the vegetable pathogen Phytophthora capsici. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2012; 25:1350-60. [PMID: 22712506 PMCID: PMC3551261 DOI: 10.1094/mpmi-02-12-0028-r] [Citation(s) in RCA: 181] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The oomycete vegetable pathogen Phytophthora capsici has shown remarkable adaptation to fungicides and new hosts. Like other members of this destructive genus, P. capsici has an explosive epidemiology, rapidly producing massive numbers of asexual spores on infected hosts. In addition, P. capsici can remain dormant for years as sexually recombined oospores, making it difficult to produce crops at infested sites, and allowing outcrossing populations to maintain significant genetic variation. Genome sequencing, development of a high-density genetic map, and integrative genomic or genetic characterization of P. capsici field isolates and intercross progeny revealed significant mitotic loss of heterozygosity (LOH) in diverse isolates. LOH was detected in clonally propagated field isolates and sexual progeny, cumulatively affecting >30% of the genome. LOH altered genotypes for more than 11,000 single-nucleotide variant sites and showed a strong association with changes in mating type and pathogenicity. Overall, it appears that LOH may provide a rapid mechanism for fixing alleles and may be an important component of adaptability for P. capsici.
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Adopting orphans: comprehensive genetic testing of Mendelian diseases of childhood by next-generation sequencing. Expert Rev Mol Diagn 2012; 11:855-68. [PMID: 22022947 DOI: 10.1586/erm.11.70] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Orphan diseases are individually uncommon but collectively contribute significantly to pediatric morbidity, mortality and healthcare costs. Current molecular testing for rare genetic disorders is often a lengthy and costly endeavor, and in many cases a molecular diagnosis is never achieved despite extensive testing. Diseases with locus heterogeneity or overlapping signs and symptoms are especially challenging owing to the number of potential targets. Consequently, there is immense need for scalable, economical, rapid, multiplexed diagnostic testing for rare Mendelian diseases. Recent advances in next-generation sequencing and bioinformatic technologies have the potential to change the standard of care for the diagnosis of rare genetic disorders. These advances will be reviewed in the setting of a recently developed test for 592 autosomal recessive and X-linked diseases.
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Abstract
A recent report by the World Health Organization calls for implementation of community genetics programs in low- and middle-income countries (LMICs). Their focus is prevention of congenital disorders and genetic diseases at the population level, in addition to providing genetics services, including diagnosis and counseling. The proposed strategies include both newborn screening and population screening for carrier detection, in addition to lowering the incidence of congenital disorders and genetic diseases through the removal of environmental factors. In this article, we consider the potential impact of such testing on global health and highlight the near-term relevance of next-generation sequencing (NGS) and bioinformatic approaches to their implementation. Key attributes of NGS for community genetics programs are homogeneous approach, high multiplexing of diseases and samples, as well as rapidly falling costs of new technologies. In the near future, we estimate that appropriate use of population-specific test panels could cost as little as $10 for 10 Mendelian disorders and could have a major impact on diseases that currently affect 2% of children worldwide. However, the successful deployment of this technological innovation in LMICs will require high value for human life, thoughtful implementation, and autonomy of individual decisions, supported by appropriate genetic counseling and community education.
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Abstract
Of 7028 disorders with suspected Mendelian inheritance, 1139 are recessive and have an established molecular basis. Although individually uncommon, Mendelian diseases collectively account for ~20% of infant mortality and ~10% of pediatric hospitalizations. Preconception screening, together with genetic counseling of carriers, has resulted in remarkable declines in the incidence of several severe recessive diseases including Tay-Sachs disease and cystic fibrosis. However, extension of preconception screening to most severe disease genes has hitherto been impractical. Here, we report a preconception carrier screen for 448 severe recessive childhood diseases. Rather than costly, complete sequencing of the human genome, 7717 regions from 437 target genes were enriched by hybrid capture or microdroplet polymerase chain reaction, sequenced by next-generation sequencing (NGS) to a depth of up to 2.7 gigabases, and assessed with stringent bioinformatic filters. At a resultant 160x average target coverage, 93% of nucleotides had at least 20x coverage, and mutation detection/genotyping had ~95% sensitivity and ~100% specificity for substitution, insertion/deletion, splicing, and gross deletion mutations and single-nucleotide polymorphisms. In 104 unrelated DNA samples, the average genomic carrier burden for severe pediatric recessive mutations was 2.8 and ranged from 0 to 7. The distribution of mutations among sequenced samples appeared random. Twenty-seven percent of mutations cited in the literature were found to be common polymorphisms or misannotated, underscoring the need for better mutation databases as part of a comprehensive carrier testing strategy. Given the magnitude of carrier burden and the lower cost of testing compared to treating these conditions, carrier screening by NGS made available to the general population may be an economical way to reduce the incidence of and ameliorate suffering associated with severe recessive childhood disorders.
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C6/36 Aedes albopictus cells have a dysfunctional antiviral RNA interference response. PLoS Negl Trop Dis 2010; 4:e856. [PMID: 21049065 PMCID: PMC2964293 DOI: 10.1371/journal.pntd.0000856] [Citation(s) in RCA: 236] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Accepted: 09/24/2010] [Indexed: 12/02/2022] Open
Abstract
Mosquitoes rely on RNA interference (RNAi) as their primary defense against viral infections. To this end, the combination of RNAi and invertebrate cell culture systems has become an invaluable tool in studying virus-vector interactions. Nevertheless, a recent study failed to detect an active RNAi response to West Nile virus (WNV) infection in C6/36 (Aedes albopictus) cells, a mosquito cell line frequently used to study arthropod-borne viruses (arboviruses). Therefore, we sought to determine if WNV actively evades the host's RNAi response or if C6/36 cells have a dysfunctional RNAi pathway. C6/36 and Drosophila melanogaster S2 cells were infected with WNV (Flaviviridae), Sindbis virus (SINV, Togaviridae) and La Crosse virus (LACV, Bunyaviridae) and total RNA recovered from cell lysates. Small RNA (sRNA) libraries were constructed and subjected to high-throughput sequencing. In S2 cells, virus-derived small interfering RNAs (viRNAs) from all three viruses were predominantly 21 nt in length, a hallmark of the RNAi pathway. However, in C6/36 cells, viRNAs were primarily 17 nt in length from WNV infected cells and 26–27 nt in length in SINV and LACV infected cells. Furthermore, the origin (positive or negative viral strand) and distribution (position along viral genome) of S2 cell generated viRNA populations was consistent with previously published studies, but the profile of sRNAs isolated from C6/36 cells was altered. In total, these results suggest that C6/36 cells lack a functional antiviral RNAi response. These findings are analogous to the type-I interferon deficiency described in Vero (African green monkey kidney) cells and suggest that C6/36 cells may fail to accurately model mosquito-arbovirus interactions at the molecular level. Cell culture systems are invaluable tools for studying virus-host interactions. These systems are typically easy to maintain and manipulate; however, they can fail to accurately mimic the host environment encountered by viruses. Therefore, defining the limitations of each system is critical to properly interpreting the results. C6/36 Aedes albopictus cells are commonly used to study arthropod-borne viruses (arboviruses), such as West Nile virus (WNV). Recent evidence suggests that the RNA interference (RNAi) pathway, a critical aspect of the cellular innate antiviral immune response in invertebrates, may not actively target WNV in C6/36 cells. However, it is unknown whether this observation is limited to WNV. Therefore, we examined small RNA populations from C6/36 and Drosophila melanogastor S2 cells infected with WNV, Sindbis virus and La Crosse virus by high-throughput sequencing. We demonstrate that the RNAi pathway actively targets each of the three viruses in S2 cells, but does not in C6/36 cells. These findings suggest that C6/36 cells may fail to accurately model mosquito-arbovirus interactions.
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Genome, epigenome and RNA sequences of monozygotic twins discordant for multiple sclerosis. Nature 2010; 464:1351-6. [PMID: 20428171 PMCID: PMC2862593 DOI: 10.1038/nature08990] [Citation(s) in RCA: 341] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2009] [Accepted: 03/11/2010] [Indexed: 12/15/2022]
Abstract
Identical (or more correctly 'monozygotic') twins are widely used to study the contributions of genetics and environment to human disease. A study that focused on three pairs of monozygotic twins, in which one twin had multiple sclerosis and the other did not, has brought the latest techniques of genome sequencing and analysis to this field, and incidentally published the first female human genome sequences. Full sequences were determined for one pair of twins, and for these and the other two pairs the mRNA transcriptome and epigenome sequences of CD4+ lymphocytes were determined. The striking result is that no genetic, epigenetic or transcriptome differences were found that explained why one twin had the disease and the other did not. Digging deeper into the data, eQTL (expression quantitative trait locus) mapping revealed tantalizing differences within twin pairs that merit closer examination. And some possible causes can be ruled out. Future work might usefully concentrate on studies of other cell types and epigenetic modifications. Studies of identical twins are widely used to dissect the contributions of genes and the environment to human diseases. In multiple sclerosis, an autoimmune demyelinating disease, identical twins often show differences. This might suggest that environmental effects are most significant in this case, but genetic and epigenetic differences between identical twins have been described. Here, however, studies of identical twins show no evidence for genetic, epigenetic or transcriptome differences that could explain disease discordance. Monozygotic or ‘identical’ twins have been widely studied to dissect the relative contributions of genetics and environment in human diseases. In multiple sclerosis (MS), an autoimmune demyelinating disease and common cause of neurodegeneration and disability in young adults, disease discordance in monozygotic twins has been interpreted to indicate environmental importance in its pathogenesis1,2,3,4,5,6,7,8. However, genetic and epigenetic differences between monozygotic twins have been described, challenging the accepted experimental model in disambiguating the effects of nature and nurture9,10,11,12. Here we report the genome sequences of one MS-discordant monozygotic twin pair, and messenger RNA transcriptome and epigenome sequences of CD4+ lymphocytes from three MS-discordant, monozygotic twin pairs. No reproducible differences were detected between co-twins among ∼3.6 million single nucleotide polymorphisms (SNPs) or ∼0.2 million insertion-deletion polymorphisms. Nor were any reproducible differences observed between siblings of the three twin pairs in HLA haplotypes, confirmed MS-susceptibility SNPs, copy number variations, mRNA and genomic SNP and insertion-deletion genotypes, or the expression of ∼19,000 genes in CD4+ T cells. Only 2 to 176 differences in the methylation of ∼2 million CpG dinucleotides were detected between siblings of the three twin pairs, in contrast to ∼800 methylation differences between T cells of unrelated individuals and several thousand differences between tissues or between normal and cancerous tissues. In the first systematic effort to estimate sequence variation among monozygotic co-twins, we did not find evidence for genetic, epigenetic or transcriptome differences that explained disease discordance. These are the first, to our knowledge, female, twin and autoimmune disease individual genome sequences reported.
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Genomic convergence analysis of schizophrenia: mRNA sequencing reveals altered synaptic vesicular transport in post-mortem cerebellum. PLoS One 2008; 3:e3625. [PMID: 18985160 PMCID: PMC2576459 DOI: 10.1371/journal.pone.0003625] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2008] [Accepted: 10/10/2008] [Indexed: 02/06/2023] Open
Abstract
Schizophrenia (SCZ) is a common, disabling mental illness with high heritability but complex, poorly understood genetic etiology. As the first phase of a genomic convergence analysis of SCZ, we generated 16.7 billion nucleotides of short read, shotgun sequences of cDNA from post-mortem cerebellar cortices of 14 patients and six, matched controls. A rigorous analysis pipeline was developed for analysis of digital gene expression studies. Sequences aligned to approximately 33,200 transcripts in each sample, with average coverage of 450 reads per gene. Following adjustments for confounding clinical, sample and experimental sources of variation, 215 genes differed significantly in expression between cases and controls. Golgi apparatus, vesicular transport, membrane association, Zinc binding and regulation of transcription were over-represented among differentially expressed genes. Twenty three genes with altered expression and involvement in presynaptic vesicular transport, Golgi function and GABAergic neurotransmission define a unifying molecular hypothesis for dysfunction in cerebellar cortex in SCZ.
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Observation of nonmagnetic resonant scattering effects by tunneling in dilute Al-mn alloy superconductors. PHYSICAL REVIEW LETTERS 2008; 100:056804. [PMID: 18352409 DOI: 10.1103/physrevlett.100.056804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2005] [Revised: 10/24/2007] [Indexed: 05/26/2023]
Abstract
We have observed the BCS-like density of states predicted for energy-gap suppression by nonmagnetic Anderson impurities in superconductors. We show that Mn impurities in Al exhibit no magnetic character and act exclusively as strong resonant scattering sites without producing time-reverse symmetry breaking of Cooper pairs (pair breaking).
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Abstract
High-throughput DNA sequencing has enabled systems biology to begin to address areas in health, agricultural and basic biological research. Concomitant with the opportunities is an absolute necessity to manage significant volumes of high-dimensional and inter-related data and analysis. Alpheus is an analysis pipeline, database and visualization software for use with massively parallel DNA sequencing technologies that feature multi-gigabase throughput characterized by relatively short reads, such as Illumina-Solexa (sequencing-by-synthesis), Roche-454 (pyrosequencing) and Applied Biosystem's SOLiD (sequencing-by-ligation). Alpheus enables alignment to reference sequence(s), detection of variants and enumeration of sequence abundance, including expression levels in transcriptome sequence. Alpheus is able to detect several types of variants, including non-synonymous and synonymous single nucleotide polymorphisms (SNPs), insertions/deletions (indels), premature stop codons, and splice isoforms. Variant detection is aided by the ability to filter variant calls based on consistency, expected allele frequency, sequence quality, coverage, and variant type in order to minimize false positives while maximizing the identification of true positives. Alpheus also enables comparisons of genes with variants between cases and controls or bulk segregant pools. Sequence-based differential expression comparisons can be developed, with data export to SAS JMP Genomics for statistical analysis.
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A novel activating function of c-Src and Stat3 on HGF transcription in mammary carcinoma cells. Oncogene 2006; 25:2773-84. [PMID: 16407846 DOI: 10.1038/sj.onc.1209306] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In the normal breast, hepatocyte growth factor (HGF) is primarily expressed by stromal cells, and stimulates in a paracrine manner epithelial cells expressing the HGF receptor (Met). In invasive human breast carcinomas, HGF and Met are frequently overexpressed, possibly establishing an autocrine HGF/Met loop that promotes tumour cell invasion. However, the mechanisms leading to autocrine HGF expression in carcinoma cells are not known. We previously demonstrated a cooperative effect between c-Src and Stat3 in the activation of HGF transcription in mammary carcinoma cells. The present report defines a novel Stat3 consensus site at nt -95 in the HGF promoter that is highly conserved in human and mouse, and is required for c-Src and Stat3 to activate HGF transcription in breast epithelial cells. DNA-protein binding studies demonstrated high affinity binding of a Stat3-containing complex to the nt -95 site. Endogenous Stat3 binding to this region of the HGF promoter in carcinoma cells expressing HGF was demonstrated using a chromatin immunoprecipitation assay. In addition, coexpression of Stat3 and activated c-Src caused increased expression of endogenous HGF mRNA and protein and marked cell scattering in breast epithelial cells. Our results delineate a novel c-Src/Stat3-dependent mechanism that regulates HGF promoter activity, and is linked to transformation of mammary epithelial cells.
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Cytopathology of the Breast: McKee GT. ( 130.00.) Oxford University Press, 2002. ISBN 0 19 514006 0. Clin Mol Pathol 2003. [DOI: 10.1136/jcp.56.8.640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Abstract
DNA macroarrays are used in many areas of molecular biology research for applications ranging from gene discovery to gene expression profiling. As an increasing number of specialized macroarrays containing genes related by function or pathway are becoming available, a question that needs to be addressed is the level of hybridization signal specificity between highly similar genes that can be achieved. We have examined the ability of our LifeGrid macroarrays to distinguish hybridization signals between closely related genes. We determined the level of cross-hybridization among genes ranging from 52% to 94% sequence identity. Fragments of genes fromfive protein families were arrayed onto nylonfilters. Thefilters were subsequently hybridized with a 33P-labeled probe prepared from a pool of synthetic mRNA transcripts containing a representative of each protein family. We found that fragments containing sequences with up to 94% sequence identity displayed relatively little cross-hybridization. We conclude that this macroarray system is very specific and that hybridization signals from closely related genes can be reliably measured.
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In situ duct carcinoma of the breast: clinical and histopathologic factors and association with recurrent carcinoma. Breast J 2001; 7:292-302. [PMID: 11906438 DOI: 10.1046/j.1524-4741.2001.99124.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
There has been a recent increase in the diagnosis of in situ duct carcinoma of the breast (DCIS) as a result of mammographic screening. DCIS is heterogeneous in appearance and likely in prognosis. There is no generally accepted model to predict progression to invasive carcinoma. We investigated the prognostic effect of clinical presentation and pathologic factors for women diagnosed with primary DCIS. A cohort of 124 patients was accrued between 1979 and 1994 and was followed to 1997; 78 had DCIS detected mammographically, and 88 underwent lumpectomy alone. In this article, we provide details about characteristics affecting the choice of primary therapeutic modality, and we examine the effects of factors on progression for the two patient subgroups. Presentation with bloody nipple discharge was associated with a significant increase in DCIS recurrence (p=0.07). The pattern of duct distribution was important: DCIS in which the involved ducts were more widely separated had a significantly greater recurrence of DCIS than when the involved ducts were more concentrated (p=0.08 for mammographically detected DCIS, p=0.07 for patients who underwent lumpectomy alone). For mammographically detected DCIS, younger patients had more DCIS recurrence (p=0.07). We found considerable heterogeneity in nuclear grade; 50% of patients exhibited more than one grade. Nuclear grade, necrosis, and architecture were not significantly associated with either recurrence of DCIS or development of invasive carcinoma. Longer follow-up will allow further evaluation of the prognostic relevance of the factors assessed.
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Use of Medicaid 1915(c) home- and community-based care waivers to reconfigure state long-term care systems. Med Care Res Rev 2001; 58:100-19. [PMID: 11236230 DOI: 10.1177/107755870105800106] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Since Congressional authorization in 1981, Medicaid 1915(c) home- and community-based care waivers have influenced states' efforts to transform their long-term care systems. In 1997, every state participated in the 1915(c) waiver program, while waiver expenditures, at $8.1 billion, represented 59.6 percent of all Medicaid community-based care expenditures. To explore state-level factors that appear related to these expenditures, the authors turn to a body of work on Medicaid resource allocation. They compare the influence of five factors--sociodemographic, supply, economic, programmatic, and political environment--on states' allocations to long-term care expenditures and 1915(c) waiver expenditures. The state economic environment was an important influence on total, as well as waiver expenditures. State regulation of long-term care supply demonstrated the most substantive relationship, increasing the share of dollars supporting 1915(c) waivers from 11.6 to 20.0 over the study period, all else equal.
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Abstract
When crestal volume is greatly insufficient for the placement of dental implants, bone grafting is usually the most reliable ridge augmentation procedure. The grafts are most often taken in parietal or mandibular symphysis regions. Though not too noticeable, it seems contra-indicated and even potentially dangerous to leave zones like the cranium to repair spontaneously. Guided bone regeneration techniques have shown their ability to regenerate new bone under difficult conditions in jaws. Their use in bone graft donor sites is simple and the results are consistent. This report shows that 2 types of resorbable membranes are equally as efficacious in terms of new-bone formation.
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Trends and issues in the Medicaid 1915(c) waiver program. HEALTH CARE FINANCING REVIEW 1999; 20:139-60. [PMID: 11482119 PMCID: PMC4194610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Over the past 15 years, Medicaid 1915(c) home and community-based waivers have made a substantial contribution to States' efforts to transform their long-term care (LTC) systems from largely institutional to community-based systems. By 1997, every State had implemented a waiver program for at least some subgroups of individuals with disabilities, and expenditures increased from $3.8 million in 1982 to more than $8.1 billion in 1997. Emerging, as well as long-standing, policy issues related to the waiver program include concerns with access, variation in availability by disability group, State decisions related to the provision of community-based LTC, and evidence on effectiveness.
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Assessment of treatment for patients with primary ductal carcinoma in situ in the breast. Ann Surg Oncol 1998; 5:724-32. [PMID: 9869520 DOI: 10.1007/bf02303484] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Current mammographic technology has resulted in increased detection of ductal carcinoma in situ (DCIS). It is necessary to assess which patients presenting with DCIS are good candidates for breast conservation and which of these patients should receive adjuvant radiation. METHODS We accrued clinical data for 124 patients with a primary diagnosis of DCIS from 1979 through 1994. Primary therapy was a mastectomy for 18 patients, and a lumpectomy for 106 patients. Only 18 of the latter group of patients received adjuvant radiotherapy. For the 88 lumpectomy-alone patients (median follow-up, 5.2 years), we evaluated the effects of clinical (age and initial presentation) and pathologic (nuclear grade, architecture, parenchymal involvement, calcifications, and measured margins) factors on recurrence of DCIS or the development of invasive breast cancer. RESULTS Patients who underwent lumpectomy with or without adjuvant radiotherapy (median follow-up, 5.0 years) were significantly more likely to have recurrence of DCIS (P=.05) than those who underwent mastectomy (median follow-up, 6.7 years): 18% (19/106) versus 0% (0/18), respectively; lumpectomy-alone patients experienced a 19% (17/88) rate of DCIS recurrence. All recurrent DCIS was ipsilateral. For lumpectomy-alone patients, the factors associated with ipsilateral recurrence of DCIS were extent of involvement of the parenchyma (P=.01, for univariate; P=.07, for multivariate) and initial presentation (P=.05, for univariate; P=.07, for multivariate). Eleven lumpectomy-alone patients developed invasive breast cancer (6 ipsilateral, 5 contralateral); none of the 18 lumpectomy patients who received adjuvant radiation developed invasive disease. None of the factors investigated, including primary surgery and adjuvant radiotherapy, were associated with a significant effect on the development of invasive disease. CONCLUSIONS Longer follow-up is required to determine if the benefits of either mastectomy or radiotherapy following lumpectomy persist. There is a suggestion that patients under 40 years of age or women who present with nipple discharge might be considered for either adjuvant radiotherapy following lumpectomy or a simple mastectomy.
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Joining forces to improve point-of-care testing. Nurs Manag (Harrow) 1997; 28:34-7. [PMID: 9325951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Point-of-care (POC) testing takes a "laboratory" test directly to the patient's bedside. Although bedside testing is not new, the compliance standards are relatively new. Regulations ensure that all personnel are trained to properly perform the test. The central laboratory and nursing of this hospital merge the best skills of both units to create a successful POC testing program.
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Transforming the long-term care system: policy and managerial challenges. HEALTH CARE MANAGEMENT (PHILADELPHIA, PA.) 1997; 3:9-22. [PMID: 10173088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
As the need for long-term care of people with disabilities increases, the model of care faces crucial changes, including a shift from institutional to independent living, significant changeover in organizational auspices, and policies created by the Americans with Disabilities Act. Such systemic changes pose fiscal, technological, and social challenges to policymakers and managers of care delivery.
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