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2.
Geroscience ; 45(4): 2303-2324, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36881352

ABSTRACT

FOXO3 is a ubiquitous transcription factor expressed in response to cellular stress caused by nutrient deprivation, inflammatory cytokines, reactive oxygen species, radiation, hypoxia, and other factors. We showed previously that the association of inherited FOXO3 variants with longevity was the result of partial protection against mortality risk posed by aging-related life-long stressors, particularly cardiometabolic disease. We then referred to the longevity-associated genotypes as conferring "mortality resilience." Serum proteins whose levels change with aging and are associated with mortality risk may be considered as "stress proteins." They may serve as indirect measures of life-long stress. Our aims were to (1) identify stress proteins that increase with aging and are associated with an increased risk of mortality, and (2) to determine if FOXO3 longevity/resilience genotype dampens the expected increase in mortality risk they pose. A total of 4500 serum protein aptamers were quantified using the Somalogic SomaScan proteomics platform in the current study of 975 men aged 71-83 years. Stress proteins associated with mortality were identified. We then used age-adjusted multivariable Cox models to investigate the interaction of stress protein with FOXO3 longevity-associated rs12212067 genotypes. For all the analyses, the p values were corrected for multiple comparisons by false discovery rate. This led to the identification of 44 stress proteins influencing the association of FOXO3 genotype with reduced mortality. Biological pathways were identified for these proteins. Our results suggest that the FOXO3 resilience genotype functions by reducing mortality in pathways related to innate immunity, bone morphogenetic protein signaling, leukocyte migration, and growth factor response.


Subject(s)
Longevity , Proteomics , Male , Humans , Longevity/genetics , Forkhead Box Protein O3/genetics , Forkhead Box Protein O3/metabolism , Genotype , Heat-Shock Proteins
3.
Pediatr Dev Pathol ; 25(6): 604-610, 2022.
Article in English | MEDLINE | ID: mdl-36082400

ABSTRACT

BACKGROUND: Workload measurement is important to help determine optimal staffing and workload distribution for pathology laboratories. The Level 4 Equivalent (L4E) System is the most widely used Anatomical Pathology (AP) workload measurement tool in Canada. However, it was initially not developed with subspecialties in mind. METHODS: In 2016, a Pan-Canadian Pediatric-Perinatal Pathology Workload Committee (PCPPPWC) was organized to adapt the L4E System to assess Pediatric-Perinatal Pathology workload. Four working groups were formed. The Placental Pathology Working Group was tasked to develop a scheme for fair valuation of placental specimens signed out by subspecialists in the context of the L4E System. Previous experience, informal time and motion studies, a survey of Canadian Pediatric-Perinatal Pathologists, and interviews of Pathologists' Assistants (PA) informed the development of such scheme. RESULTS: A workload measurement scheme with average L4E workload values for examination and reporting of singleton and multiple gestation placentas was proposed. The proposal was approved by the Canadian Association of Pathologist - Association canadienne des pathologistes Workload and Human Resources Committee for adoption into the L4E System. CONCLUSION: The development of a workload measurement model for placental specimens provides an average and fair valuation of these specimen types, enabling its use for resource planning and workload distribution.


Subject(s)
Pathology Department, Hospital , Placenta , Female , Pregnancy , Humans , Child , Canada , Workload
4.
EBioMedicine ; 67: 103326, 2021 May.
Article in English | MEDLINE | ID: mdl-33965347

ABSTRACT

BACKGROUND: The umbilical artery (UA) Doppler pulsatility index is used clinically to detect elevated feto-placental vascular resistance. However, this metric is confounded by variation in fetal cardiac function and is only moderately predictive of placental pathology. Our group developed a novel ultrasound methodology that measures wave reflections in the UA, thereby isolating a component of the Doppler signal that is specific to the placenta. The present study examined whether wave reflections in the UA are predictive of placental vascular pathology. METHODS: Standard clinical Doppler ultrasound of the UAs was performed in 241 pregnant women. Of these, 40 women met narrowly defined preset criteria for the control group, 36 had maternal vascular malperfusion (MVM) and 16 had fetal vascular malperfusion (FVM). Using a computational procedure, the Doppler waveforms were decomposed into a pair of forward and backward propagating waves. FINDINGS: Compared to controls, wave reflections were significantly elevated in women with either MVM (p<0.0001) or FVM pathology (p = 0.02). In contrast, the umbilical and uterine artery pulsatility indices were only elevated in the MVM group (p<0.0001) and there were no differences between women with FVM and the controls. INTERPRETATION: The measurement of wave reflections in the UA, combined with standard clinical ultrasound parameters, has the potential to improve the diagnostic performance of UA Doppler to detect placental vascular pathology. Identifying women with FVM pathology is particularly challenging prenatally and future investigations will determine if women at risk of this specific placental disease could benefit from this novel diagnostic technique.


Subject(s)
Placenta Diseases/diagnostic imaging , Placenta/diagnostic imaging , Ultrasonography, Doppler, Pulsed/methods , Umbilical Arteries/diagnostic imaging , Adolescent , Adult , Female , Humans , Placenta/blood supply , Placenta/pathology , Placental Circulation , Pregnancy , Umbilical Arteries/physiology , Umbilical Arteries/physiopathology
5.
Clin Genet ; 98(6): 613-619, 2020 12.
Article in English | MEDLINE | ID: mdl-32888207

ABSTRACT

Glutamine synthetase (GS) is the enzyme responsible for the biosynthesis of glutamine, providing the only source of endogenous glutamine necessary for several critical metabolic and developmental pathways. GS deficiency, caused by pathogenic variants in the glutamate-ammonia ligase (GLUL) gene, is a rare autosomal recessive inborn error of metabolism characterized by systemic glutamine deficiency, persistent moderate hyperammonemia, and clinically devastating seizures and multi-organ failure shortly after birth. The four cases reported thus far were caused by homozygous GLUL missense variants. We report a case of GS deficiency caused by homozygous GLUL gene deletion, diagnosed prenatally and likely representing the most severe end of the spectrum. We expand the known phenotype of this rare condition with novel dysmorphic, radiographic and neuropathologic features identified on post-mortem examination. The biallelic deletion identified in this case also included the RNASEL gene and was associated with immune dysfunction in the fetus. This case demonstrates that total absence of the GLUL gene in humans is viable beyond the embryonic period, despite the early embryonic lethality found in GLUL animal models.


Subject(s)
Amino Acid Metabolism, Inborn Errors/genetics , Glutamate-Ammonia Ligase/deficiency , Glutamate-Ammonia Ligase/genetics , Adult , Amino Acid Metabolism, Inborn Errors/pathology , Female , Fetus , Glutamine/genetics , Homozygote , Humans , Infant, Newborn , Male , Metabolic Diseases/genetics , Metabolic Diseases/pathology
6.
Int J Obes (Lond) ; 44(7): 1596-1606, 2020 07.
Article in English | MEDLINE | ID: mdl-32467615

ABSTRACT

BACKGROUND: Obesity and its associated diseases are major health problems characterized by extensive metabolic disturbances. Understanding the causal connections between these phenotypes and variation in metabolite levels can uncover relevant biology and inform novel intervention strategies. Recent studies have combined metabolite profiling with genetic instrumental variable (IV) analysis (Mendelian randomization) to infer the direction of causality between metabolites and obesity, but often omitted a large portion of untargeted profiling data consisting of unknown, unidentified metabolite signals. METHODS: We expanded upon previous research by identifying body mass index (BMI)-associated metabolites in multiple untargeted metabolomics datasets, and then performing bidirectional IV analysis to classify metabolites based on their inferred causal relationships with BMI. Meta-analysis and pathway analysis of both known and unknown metabolites across datasets were enabled by our recently developed bioinformatics suite, PAIRUP-MS. RESULTS: We identified ten known metabolites that are more likely to be causes (e.g., alpha-hydroxybutyrate) or effects (e.g., valine) of BMI, or may have more complex bidirectional cause-effect relationships with BMI (e.g., glycine). Importantly, we also identified about five times more unknown than known metabolites in each of these three categories. Pathway analysis incorporating both known and unknown metabolites prioritized 40 enriched (p < 0.05) metabolite sets for the cause versus effect groups, providing further support that these two metabolite groups are linked to obesity via distinct biological mechanisms. CONCLUSIONS: These findings demonstrate the potential utility of our approach to uncover causal connections with obesity from untargeted metabolomics datasets. Combining genetically informed causal inference with the ability to map unknown metabolites across datasets provides a path to jointly analyze many untargeted datasets with obesity or other phenotypes. This approach, applied to larger datasets with genotype and untargeted metabolite data, should generate sufficient power for robust discovery and replication of causal biological connections between metabolites and various human diseases.


Subject(s)
Metabolome , Obesity/metabolism , Body Mass Index , Causality , Computational Biology , Humans , Metabolomics , Obesity/genetics
7.
Aging (Albany NY) ; 11(18): 7694-7706, 2019 09 26.
Article in English | MEDLINE | ID: mdl-31557729

ABSTRACT

Glucuronic acid is a metabolite of glucose that is involved in the detoxification of xenobiotic compounds and the structure/remodeling of the extracellular matrix. We report for the first time that circulating glucuronic acid is a robust biomarker of mortality that is conserved across species. We find that glucuronic acid levels are significant predictors of all-cause mortality in three population-based cohorts from different countries with 4-20 years of follow-up (HR=1.44, p=2.9×10-6 in the discovery cohort; HR=1.13, p=0.032 and HR=1.25, p=0.017, respectively in the replication cohorts), as well as in a longitudinal study of genetically heterogenous mice (HR=1.29, p=0.018). Additionally, we find that glucuronic acid levels increase with age and predict future healthspan-related outcomes. Together, these results demonstrate glucuronic acid as a robust biomarker of longevity and healthspan.


Subject(s)
Glucuronic Acid/blood , Healthy Aging/blood , Longevity/physiology , Adult , Age Factors , Aged , Animals , Biomarkers/blood , Blood Pressure/physiology , Body Mass Index , Female , Humans , Longitudinal Studies , Male , Metabolomics , Mice , Middle Aged
8.
Am J Physiol Heart Circ Physiol ; 316(5): H1105-H1112, 2019 05 01.
Article in English | MEDLINE | ID: mdl-30794433

ABSTRACT

The pulsatile pattern of blood motion measured by Doppler ultrasound within the umbilical artery is known to contain useful diagnostic information and is widely used to monitor pregnancies at risk of fetal growth restriction or stillbirth. Animal studies have identified reflected pressure waves traveling counter to the direction of blood flow as an important factor in the shape of these waveforms. In the present study, we establish a method to measure reflected waves in the human umbilical artery and assess their influence on blood velocity pulsation. Ninety-five pregnant women were recruited from a general obstetrics clinic between 26 and 37 wk of gestation and examined by Doppler ultrasound. Blood velocity waveforms were recorded for each umbilical artery at three locations along the umbilical cord. With the use of a computational procedure, a pair of forward and reverse propagating waves was identified to explain the variation in observed Doppler ultrasound waveforms along the cord. Among the data sets that met data quality requirements, waveforms in 93 of the 130 arteries examined agreed with the wave reflection model to within 1.5% and showed reflections ranging in magnitude from 3 to 52% of the forward wave amplitude. Strong reflections were associated with large differences in pulsatility between the fetal and placental ends of the cord. As reflections arise from transitions in the biomechanical properties of blood vessels, these observations provide a plausible mechanism for the link between abnormal waveforms and clinically significant placental pathology and could lead to more precise screening methods for detecting pregnancies complicated by placental disease. NEW & NOTEWORTHY The pulsatile pattern of blood motion measured by Doppler ultrasound within the umbilical artery is known to contain useful diagnostic information and is widely used to monitor pregnancies at risk of fetal growth restriction. We demonstrate based on a study of 95 pregnant women that the shape of these umbilical artery waveforms is explained by the presence of a reflected pressure wave traveling counter to the direction of blood flow.


Subject(s)
Pulsatile Flow , Ultrasonography, Doppler , Ultrasonography, Prenatal/methods , Umbilical Arteries/diagnostic imaging , Adolescent , Adult , Baltimore , Blood Flow Velocity , Female , Humans , Models, Cardiovascular , Ontario , Predictive Value of Tests , Pregnancy , Umbilical Arteries/physiology , Young Adult
9.
PLoS Comput Biol ; 15(1): e1006734, 2019 01.
Article in English | MEDLINE | ID: mdl-30640898

ABSTRACT

Metabolomics is a powerful approach for discovering biomarkers and for characterizing the biochemical consequences of genetic variation. While untargeted metabolite profiling can measure thousands of signals in a single experiment, many biologically meaningful signals cannot be readily identified as known metabolites nor compared across datasets, making it difficult to infer biology and to conduct well-powered meta-analyses across studies. To overcome these challenges, we developed a suite of computational methods, PAIRUP-MS, to match metabolite signals across mass spectrometry-based profiling datasets and to generate metabolic pathway annotations for these signals. To pair up signals measured in different datasets, where retention times (RT) are often not comparable or even available, we implemented an imputation-based approach that only requires mass-to-charge ratios (m/z). As validation, we treated each shared known metabolite as an unmatched signal and showed that PAIRUP-MS correctly matched 70-88% of these metabolites from among thousands of signals, equaling or outperforming a standard m/z- and RT-based approach. We performed further validation using genetic data: the most stringent set of matched signals and shared knowns showed comparable consistency of genetic associations across datasets. Next, we developed a pathway reconstitution method to annotate unknown signals using curated metabolic pathways containing known metabolites. We performed genetic validation for the generated annotations, showing that annotated signals associated with gene variants were more likely to be enriched for pathways functionally related to the genes compared to random expectation. Finally, we applied PAIRUP-MS to study associations between metabolites and genetic variants or body mass index (BMI) across multiple datasets, identifying up to ~6 times more significant signals and many more BMI-associated pathways compared to the standard practice of only analyzing known metabolites. These results demonstrate that PAIRUP-MS enables analysis of unknown signals in a robust, biologically meaningful manner and provides a path to more comprehensive, well-powered studies of untargeted metabolomics data.


Subject(s)
Computational Biology/methods , Mass Spectrometry/methods , Metabolome , Metabolomics/methods , Aged , Aged, 80 and over , Biomarkers/analysis , Biomarkers/metabolism , Databases, Factual , Humans , Metabolic Networks and Pathways/physiology , Metabolome/genetics , Metabolome/physiology
10.
Cancer Med ; 7(11): 5478-5487, 2018 11.
Article in English | MEDLINE | ID: mdl-30318772

ABSTRACT

BACKGROUND: Two germ line Fc-γ receptor (FCGR) polymorphisms, rs1801274 [FCGR2A; His(H)131Arg(R)] and rs396991 [FCGR3A; Phe(F)158Val(V)], produce altered proteins through amino acid substitutions. We previously reported that the FCGR2A H/H genotype was associated with longer overall survival (OS) in cetuximab-treated chemotherapy-refractory patients with metastatic colorectal cancer. Here, we aimed to replicate and extend this finding in the Canadian Clinical Trials Group CO.20 trial. METHODS: After germ line DNA genotyping, polymorphic relationships with survival were assessed using log-rank tests and hazard ratios (HR) from Cox proportional hazard models, adjusting for known prognostic factors. The dominant genetic inheritance model was used for the main analysis. RESULTS: Of 592 wild-type KRAS patients treated with cetuximab, those with the FCGR2A H/H genotype (n = 165, 28%) had improved OS (HR: 0.66, P < 0.001; median absolute benefit, 1.3 months) compared to those with R/- genotype (n = 427, 72%). Patients with H/R had intermediate results under a codominant genetic inheritance model (HR: 0.72, P = 0.003). No significant associations were found between FCGR3A genotype and OS. In an exploratory analysis, patients with the combination of FCGR2A H/H + FCGR3A F/F genotype had significantly better OS (HR: 0.33, P = 0.003; median absolute benefit, 12.5 months) than patients with the combination of double-variant R/R + V/V genotype. Progression-free survival results were similar to OS. Toxicity rates were not associated with either polymorphism. CONCLUSIONS: The FCGR2A genotype was associated with efficacy but not with toxicity in wild-type KRAS, cetuximab-treated colorectal cancer patients. FCGR3A genotype may modulate the relationship between FCGR2A polymorphism and outcome. FCGR2A is a promising biomarker for clinical management for these patients.


Subject(s)
Colorectal Neoplasms/genetics , Receptors, IgG/genetics , Aged , Alanine/analogs & derivatives , Alanine/therapeutic use , Antineoplastic Agents/therapeutic use , Cetuximab/therapeutic use , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/mortality , Colorectal Neoplasms/pathology , Female , Humans , Male , Middle Aged , Polymorphism, Genetic , Survival Analysis , Triazines/therapeutic use
11.
J Pediatr Genet ; 7(3): 134-137, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30105123

ABSTRACT

Traditional approaches to prenatal genetic diagnosis for common presentations such as short femurs or intrauterine growth restriction are imperfect, and whole-exome sequencing is an emerging option. Mucolipidosis type II (I-cell disease) is an ultra-rare autosomal recessive lysosomal storage disorder with the potential for prenatal-onset skeletal and placental manifestations. We describe the prenatal signs in two recent unrelated patients with confirmed diagnoses soon after birth. In both cases, parents were consanguineous but there was no known family history of mucolipidosis type II. False reassurance was provided after negative testing for another disease with overlapping prenatal manifestations already present in one of the families, emphasizing that offspring of consanguineous parents can be at risk for more than one recessive condition. Our experience illustrates the potential advantages in expanding prenatal applications of WES for the identification of rare single gene disorders in offspring of consanguineous unions.

12.
Am J Obstet Gynecol ; 218(2S): S803-S817, 2018 02.
Article in English | MEDLINE | ID: mdl-29254754

ABSTRACT

Effective detection and management of fetal growth restriction is relevant to all obstetric care providers. Models of best practice to care for these patients and their families continue to evolve. Since much of the disease burden in fetal growth restriction originates in the placenta, the concept of a multidisciplinary placenta clinic program, managed primarily within a maternal-fetal medicine division, has gained popularity. In this context, fetal growth restriction is merely one of many placenta-related disorders that can benefit from an interdisciplinary approach, incorporating expertise from specialist perinatal ultrasound and magnetic resonance imaging, reproductive genetics, neonatal pediatrics, internal medicine subspecialties, perinatal pathology, and nursing. The accurate diagnosis and prognosis for women with fetal growth restriction is established by comprehensive clinical review and detailed sonographic evaluation of the fetus, combined with uterine artery Doppler and morphologic assessment of the placenta. Diagnostic accuracy for placenta-mediated fetal growth restriction may be enhanced by quantification of maternal serum biomarkers including placenta growth factor alone or combined with soluble fms-like tyrosine kinase-1. Uterine artery Doppler is typically abnormal in most instances of early-onset fetal growth restriction and is associated with coexistent preeclampsia and underlying maternal vascular malperfusion pathology of the placenta. By contrast, rare but potentially more serious underlying placental diagnoses, such as massive perivillous fibrinoid deposition, chronic histiocytic intervillositis, or fetal thrombotic vasculopathy, may be associated with normal uterine artery Doppler waveforms. Despite minor variations in placental size, shape, and cord insertion, placental function remains, largely normal in the general population. Consequently, morphologic assessment of the placenta is not currently incorporated into current screening programs for placental complications. However, placental ultrasound can be diagnostic in the context of fetal growth restriction, for example in Breus' mole and triploidy, which in turn may enhance diagnosis and management. Several examples are illustrated in our figures and supplementary videos. Recent advances in the ability of multiparameter screening and intervention programs to reduce the risk of severe preeclampsia will likely increase efforts to deliver similar improvements for women at risk of fetal growth restriction. Placental pathology is important because the underlying pathologies associated with fetal growth restriction have a wide range of recurrence risks. Rare conditions such as massive perivillous fibrinoid deposition or chronic histolytic intervillositis may recur in >50% of subsequent pregnancies. Postpartum care in a placenta-focused program can provide effective counseling for modifiable maternal risk factors, and can assist in planning future pregnancy care based on the pathologic basis of fetal growth restriction.


Subject(s)
Fetal Growth Retardation/diagnosis , Placental Insufficiency/diagnosis , Delivery of Health Care/organization & administration , Female , Fetal Growth Retardation/blood , Fetal Growth Retardation/therapy , Humans , Placenta Diseases/blood , Placenta Diseases/diagnosis , Placenta Diseases/therapy , Placenta Growth Factor/blood , Placental Insufficiency/blood , Placental Insufficiency/therapy , Pre-Eclampsia , Pregnancy , Ultrasonography, Doppler , Ultrasonography, Prenatal , Uterine Artery/diagnostic imaging , Vascular Endothelial Growth Factor Receptor-1/blood
13.
Placenta ; 58: 52-59, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28962696

ABSTRACT

INTRODUCTION: The placenta demonstrates a recognized sequence of histomorphologic maturation throughout pregnancy, and in some cases, shows abnormally advanced (AVM) or delayed (DVM) villous maturation. While AVM and DVM have important clinical implications, it is unknown whether they truly represent a state of accelerated/delayed normal maturation or a state of pathological maldevelopment. The purpose of our study is, therefore, to address this challenge via a genome-wide search for expression markers of normal villous maturation (NM) and the assessment of these genes in cases of maturational pathology. METHODS: A total of 142 placentas, previously evaluated by gene expression microarray, were reviewed histologically and classified as NM, AVM, or DVM. Expression data from healthy NM placentas underwent Pearson correlations with gestational age (GA) and network/pathway analysis to identify candidate gene markers. Candidates were then validated in an independent microarray dataset and used to calculate "molecular GAs" of placentas with maturational pathology. RESULTS: Analysis of NM placentas yielded 17 candidate markers of normal villous maturation, of which 11 were independently validated. Genes with expression increasing across gestation were associated with transcription and metabolism, while those demonstrating decreasing expression were involved in cell cycle and division. Molecular GA was 5.3 weeks older than true GA among AVM placentas (p < 0.001), and 1.1 weeks younger among DVM placentas (p = 0.149). DISCUSSION: We have found evidence of advanced molecular GA in AVM placentas, while molecular alterations in DVM placentas were merely suggestive of delayed maturation. In the future, these findings will need to be validated with additional techniques such as in situ hybridization or immunohistochemistry.


Subject(s)
Chorionic Villi/growth & development , Gene Expression , Placenta/metabolism , Placentation/genetics , Adult , Chorionic Villi/metabolism , Female , Gestational Age , Humans , Pre-Eclampsia/genetics , Pre-Eclampsia/metabolism , Pregnancy
14.
Aging (Albany NY) ; 9(8): 1916-1925, 2017 08 31.
Article in English | MEDLINE | ID: mdl-28858850

ABSTRACT

Biomarkers of all-cause mortality are of tremendous clinical and research interest. Because of the long potential duration of prospective human lifespan studies, such biomarkers can play a key role in quantifying human aging and quickly evaluating any potential therapies. Decades of research into mortality biomarkers have resulted in numerous associations documented across hundreds of publications. Here, we present MortalityPredictors.org, a manually-curated, publicly accessible database, housing published, statistically-significant relationships between biomarkers and all-cause mortality in population-based or generally healthy samples. To gather the information for this database, we searched PubMed for appropriate research papers and then manually curated relevant data from each paper. We manually curated 1,576 biomarker associations, involving 471 distinct biomarkers. Biomarkers ranged in type from hematologic (red blood cell distribution width) to molecular (DNA methylation changes) to physical (grip strength). Via the web interface, the resulting data can be easily browsed, searched, and downloaded for further analysis. MortalityPredictors.org provides comprehensive results on published biomarkers of human all-cause mortality that can be used to compare biomarkers, facilitate meta-analysis, assist with the experimental design of aging studies, and serve as a central resource for analysis. We hope that it will facilitate future research into human mortality and aging.


Subject(s)
Aging/metabolism , Biomarkers/metabolism , Cause of Death , Databases, Factual , Health Status , Access to Information , Age Factors , Aging/genetics , Data Mining , Genetic Markers , Genotype , Health Status Indicators , Humans , Information Dissemination , Longevity , Phenotype , Risk Factors
15.
Am J Clin Pathol ; 146(4): 478-86, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27686174

ABSTRACT

OBJECTIVES: While reference limits are foundational to interpreting clinical laboratory tests, they may not correspond to the actual values triggering clinical response. We propose to measure this using clinical action curves, which plot test values against an indicator of clinical action. METHODS: We selected repeat test ordering as a quantifiable, objective, useful measure that is readily calculable using available laboratory data. Using all results in Calgary in 2010-2011 for eight analytes, clinical action curves for each analyte were plotted as the relationship between index test value and retesting hazard, modeled using Cox proportional hazards with restricted cubic splines. Clinical action limits were defined where retesting hazard rose 38% above baseline (25%-50% considered). RESULTS: In general, clinical action increased before the reference limits, and clinical action limits were narrower than reference limits. However, some reference limits showed no increased clinical action and may thus be ignored in practice. CONCLUSIONS: Clinical action curves and limits provide practical, objective tools for describing physician responses to test values. Results suggest that many normal results are treated as abnormal and vice versa; such discrepancies require further scrutiny and ultimately reconciliation via altered reference ranges or altered practice patterns.


Subject(s)
Diagnostic Tests, Routine , Laboratories, Hospital , Clinical Decision-Making , Humans , Physicians , Reference Values , Reproducibility of Results
16.
Clin Cancer Res ; 22(10): 2435-44, 2016 05 15.
Article in English | MEDLINE | ID: mdl-27179112

ABSTRACT

PURPOSE: Two germline Fc-γ receptor (FCGR) polymorphisms, rs1801274 [FCGR2A;His(H)131Arg(R)] and rs396991 [FCGR3A;Phe(F)158Val(V)] produce altered proteins through amino acid substitutions; both are reported to be associated with cetuximab-related outcomes. We performed a validation of these polymorphisms in NCIC CTG CO.17, a randomized trial of cetuximab monotherapy in refractory, metastatic colorectal cancer expressing EGFR. EXPERIMENTAL DESIGN: DNA extracted from formalin-fixed paraffin-embedded tissue was genotyped. In addition to log-rank tests, Cox proportional hazard models assessed their relationships with overall (OS) and progression-free survival (PFS), adjusting for clinically important prognostic factors, along with a polymorphism-treatment arm interaction term. RESULTS: Somatic KRAS status was wild-type for exon 2 in 153 (52%) of 293 patients, from whom tumor DNA was available. For FCGR2A H/H, a genotype-treatment interaction for KRAS wild-type patients was observed for OS (P = 0.03). In KRAS wild-type patients carrying FCGR2A H/H, cetuximab (vs. no cetuximab) improved survival substantially, with adjusted HRs (aHR) of 0.36 (OS) and 0.19 (PFS) and absolute benefits of 5.5 months (OS; P = 0.003) and 3.7 months (PFS; P = 0.02). In contrast, patients carrying FCGR2A R alleles (H/R or R/R) had aHRs of only 0.78 (OS; 2.8-month benefit) and 0.53 (PFS; 1.6-month benefit). No relationships were found for rs396991 (FCGR3A). CONCLUSIONS: In the CO.17 trial, cetuximab worked best for patients with KRAS wild-type colorectal cancers carrying FCGR2A H/H genotypes. Significantly lower benefits were observed in patients carrying germline FCGR2A R alleles. Clin Cancer Res; 22(10); 2435-44. ©2016 AACR.


Subject(s)
Antineoplastic Agents, Immunological/therapeutic use , Cetuximab/therapeutic use , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , Polymorphism, Genetic/genetics , Receptors, IgG/genetics , Adult , Aged , Aged, 80 and over , Disease-Free Survival , ErbB Receptors/genetics , Female , Genotype , Humans , Male , Middle Aged , Retrospective Studies , ras Proteins/genetics
17.
Am J Clin Pathol ; 144(5): 704-12, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26486733

ABSTRACT

OBJECTIVES: To identify inappropriate repeats of six common laboratory tests in a population sample of patients, using highly specific criteria based only on repeat time and test value. METHODS: We used a laboratory informatics database to conduct a retrospective cohort study using a population sample of 103,000 patients in the city of Calgary with an index test in 2010 and uniform follow-up of 1 year. We examined six tests (cholesterol, hemoglobin A1c, thyroid-stimulating hormone, vitamin B12, vitamin D, and ferritin) with consensus-based or easily justified criteria for inappropriate repeats based solely on time to repeat and the index test value. RESULTS: The percentages of tests repeated at 3, 6, and 12 months were 11%, 23%, and 41%, respectively. In total, 16% of these six tests were inappropriately repeated, representing an annual internal cost of $0.6 to $2.2 million Canadian dollars and corresponding to population-scaled national estimates for Canada and the United States of $160 million and $2.4 billion, respectively. CONCLUSIONS: Objective definitions based on repeated testing identified 16% of six studied tests as inappropriate, delineating a subset of inappropriate testing that is well suited to automated identification and intervention and that provides a likely lower bound on the true burden of inappropriate testing.


Subject(s)
Diagnostic Tests, Routine/economics , Laboratories, Hospital/economics , Unnecessary Procedures/economics , Canada , Databases, Factual , Humans , Retrospective Studies
18.
Eur J Med Genet ; 55(8-9): 446-54, 2012.
Article in English | MEDLINE | ID: mdl-22612983

ABSTRACT

PURPOSE: Cytogenetic analysis of solid tissue is indispensable in perinatal care, reproductive planning, and detection of gestational trophoblastic disease. Unfortunately, methods in common use suffer from drawbacks including culture artifact, low resolution, and high cost. We propose a new diagnostic algorithm based on direct genetic analysis of tissues (without cell culture) using QF-PCR and array CGH. METHODS: Study samples consisted of specimens submitted to the cytogenetics laboratory between January and June of 2011 that were split and analyzed in parallel by our traditional algorithm (culture and G-banding, plus an interphase FISH aneuploidy panel for culture failures) and the proposed "no-culture" algorithm (first line QF-PCR, plus array CGH on normal QF-PCRs). Data on clinical impact, cost, and turnaround time were collected. RESULTS: Forty specimens were included. The algorithms produced results that were fully concordant in 22 cases, partially concordant in 9 cases, and discordant in 9 cases. The no-culture algorithm detected new, clinically-significant abnormalities in 8 of 40 cases (20%), corrected the sex chromosome assortment in 1 case, reduced the analysis failure rate from 10% to 0%, and provided at least one of these three important benefits in 12 of 40 cases (30%). The algorithm also demonstrated a reduced cost per-specimen and per diagnosis, as well as improved turnaround time, with virtually all cases reported per guidelines. CONCLUSION: These striking results favor the "no-culture" algorithm, which may have the potential to replace standard cytogenetic methods in the clinical laboratory.


Subject(s)
Chromosome Disorders/diagnosis , Comparative Genomic Hybridization , Polymerase Chain Reaction , Chromosome Aberrations , Chromosome Banding/economics , Chromosome Disorders/genetics , Comparative Genomic Hybridization/economics , Cytogenetic Analysis , Diagnostic Errors , Female , Genome, Human , Humans , In Situ Hybridization, Fluorescence/economics , Male , Polymerase Chain Reaction/economics , Polymerase Chain Reaction/methods , Tissue Culture Techniques/economics
19.
Rejuvenation Res ; 15(2): 148-52, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22533420

ABSTRACT

Calorie restriction (CR) extends life span in mammals and delays the onset of age-related diseases, including cancer and diabetes. Drugs that target the same genes and pathways as CR may have enormous therapeutic potential. Recently, genome-scale data on the responses of human cell lines to over 1,000 drug treatments have become available. Here we integrate these data with gene expression signatures of CR in mouse liver to generate a prioritized list of candidate CR mimetics. We identify 14 drugs that reproduce the effects of CR at the transcriptional level.


Subject(s)
Caloric Restriction/methods , Liver/metabolism , Animals , Cell Line , Chromosome Mapping , Computational Biology/methods , Drug Evaluation, Preclinical , Gene Expression Regulation , Genome , Genome, Human , Humans , Liver/drug effects , Mice , Oligonucleotide Array Sequence Analysis , Software , Transcription, Genetic
20.
Int J Radiat Oncol Biol Phys ; 82(2): 574-81, 2012 Feb 01.
Article in English | MEDLINE | ID: mdl-21300463

ABSTRACT

PURPOSE: To map the distribution of microscopic disease (MD) in head-and-neck cancer by analyzing digital images of whole-mounted serial sections of tongue cancer specimens. METHODS AND MATERIALS: Ten T1-3 oral tongue cancer specimens were evaluated. The specimens were sliced into 3-mm blocks from which one or more 4-µm slides were taken and digitized to create whole-mounted serial sections. Gross tumor and microscopic disease were digitally contoured on each slide. Lines perpendicular to the gross tumor volume (GTV) edge were created at 0.05-mm intervals and the distance between GTV and MD measured. RESULTS: Of 88 slides assessed, 44 (50%) had evidence of MD. Of the 63,809 perpendicular lines drawn along the GTV edges, 2320 (3.6%) encountered microscopic disease along their path. The majority of MD abutted the GTV, and only 26.7% was noncontiguous with the GTV edge. The maximum distance from the border was 7.8 mm. Ninety-nine percent of all MD was within 4.75 mm and 95% was within 3.95 mm of the GTV. CONCLUSION: In this study we were able to assess the distribution of MD more accurately than has been possible with routine pathologic techniques. The results indicate that when the GTV is correctly identified, there is very little MD to be found outside this volume. This has implications for the volume of tissue resected at surgery and the volume included in the clinical target volume in conformal radiotherapy planning.


Subject(s)
Carcinoma, Squamous Cell/ultrastructure , Head and Neck Neoplasms/radiotherapy , Histocytological Preparation Techniques/methods , Tongue Neoplasms/ultrastructure , Tumor Burden , Tumor Microenvironment , Adult , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/pathology , Diagnosis, Computer-Assisted/methods , Female , Humans , Male , Middle Aged , Neoplasm Staging/methods , Tongue Neoplasms/pathology
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