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1.
J Med Imaging (Bellingham) ; 11(2): 026001, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38435711

RESUMEN

Purpose: Diagnostic performance of prostate MRI depends on high-quality imaging. Prostate MRI quality is inversely proportional to the amount of rectal gas and distention. Early detection of poor-quality MRI may enable intervention to remove gas or exam rescheduling, saving time. We developed a machine learning based quality prediction of yet-to-be acquired MRI images solely based on MRI rapid localizer sequence, which can be acquired in a few seconds. Approach: The dataset consists of 213 (147 for training and 64 for testing) prostate sagittal T2-weighted (T2W) MRI localizer images and rectal content, manually labeled by an expert radiologist. Each MRI localizer contains seven two-dimensional (2D) slices of the patient, accompanied by manual segmentations of rectum for each slice. Cascaded and end-to-end deep learning models were used to predict the quality of yet-to-be T2W, DWI, and apparent diffusion coefficient (ADC) MRI images. Predictions were compared to quality scores determined by the experts using area under the receiver operator characteristic curve and intra-class correlation coefficient. Results: In the test set of 64 patients, optimal versus suboptimal exams occurred in 95.3% (61/64) versus 4.7% (3/64) for T2W, 90.6% (58/64) versus 9.4% (6/64) for DWI, and 89.1% (57/64) versus 10.9% (7/64) for ADC. The best performing segmentation model was 2D U-Net with ResNet-34 encoder and ImageNet weights. The best performing classifier was the radiomics based classifier. Conclusions: A radiomics based classifier applied to localizer images achieves accurate diagnosis of subsequent image quality for T2W, DWI, and ADC prostate MRI sequences.

2.
J Med Imaging (Bellingham) ; 9(3): 036001, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35721309

RESUMEN

Purpose: Multiparametric magnetic resonance imaging (mp-MRI) is being investigated for kidney cancer because of better soft tissue contrast ability. The necessity of manual labels makes the development of supervised kidney segmentation algorithms challenging for each mp-MRI protocol. Here, we developed a transfer learning-based approach to improve kidney segmentation on a small dataset of five other mp-MRI sequences. Approach: We proposed a fully automated two-dimensional (2D) attention U-Net model for kidney segmentation on T1 weighted-nephrographic phase contrast enhanced (CE)-MRI (T1W-NG) dataset ( N = 108 ). The pretrained weights of T1W-NG kidney segmentation model transferred to five other distinct mp-MRI sequences model (T2W, T1W-in-phase (T1W-IP), T1W-out-of-phase (T1W-OP), T1W precontrast (T1W-PRE), and T1W-corticomedullary-CE (T1W-CM), N = 50 ) and fine-tuned by unfreezing the layers. The individual model performances were evaluated with and without transfer-learning fivefold cross-validation on average Dice similarity coefficient (DSC), absolute volume difference, Hausdorff distance (HD), and center-of-mass distance (CD) between algorithm generated and manually segmented kidneys. Results: The developed 2D attention U-Net model for T1W-NG produced kidney segmentation DSC of 89.34 ± 5.31 % . Compared with randomly initialized weight models, the transfer learning-based models of five mp-MRI sequences showed average increase of 2.96% in DSC of kidney segmentation ( p = 0.001 to 0.006). Specifically, the transfer-learning approach increased average DSC on T2W from 87.19% to 89.90%, T1W-IP from 83.64% to 85.42%, T1W-OP from 79.35% to 83.66%, T1W-PRE from 82.05% to 85.94%, and T1W-CM from 85.65% to 87.64%. Conclusions: We demonstrate that a pretrained model for automated kidney segmentation of one mp-MRI sequence improved automated kidney segmentation on five other additional sequences.

3.
Clin Transl Gastroenterol ; 8(11): e126, 2017 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-29095427

RESUMEN

OBJECTIVES: Flow cytometry (FC) aids in characterization of cellular and molecular factors involved in pathologic immune responses. Although FC has potential to facilitate early drug development in inflammatory bowel disease, interlaboratory variability limits its use in multicenter trials. Standardization of methods may address this limitation. We compared variability in FC-aided quantitation of T-cell responses across international laboratories using three analytical strategies. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from three healthy donors, stimulated with phorbol 12-myristate 13-acetate and ionomycin at a central laboratory, fixed, frozen, and shipped to seven international laboratories. Permeabilization and staining was performed in triplicate at each laboratory using a common protocol and centrally provided reagents. Gating was performed using local gating with a local strategy (LGLS), local gating with a central strategy (LGCS), and central gating (CG). Median cell percentages were calculated across triplicates and donors, and reported for each condition and strategy. The coefficient of variation (CV) was calculated across laboratories. Between-strategy comparisons were made using a two-way analysis of variance adjusting for donor. RESULTS: Mean interlaboratory CV ranged from 1.8 to 102.1% depending on cell population and gating strategy (LGLS, 4.4-102.1%; LGCS, 10.9-65.6%; CG, 1.8-20.9%). Mean interlaboratory CV differed significantly across strategies and was consistently lower with CG. CONCLUSIONS: Central gating was the only strategy with mean CVs consistently lower than 25%, which is a proposed standard for pharmacodynamic and exploratory biomarker assays.

4.
Ann Palliat Med ; 6(Suppl 2): S233-S239, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29156909

RESUMEN

BACKGROUND: Palliative radiotherapy (RT) is effective in patients with painful bone metastases. Genetic factors may identify subgroup of patients who responded to RT. To identify DNA biomarkers associated with response to palliative RT. METHODS: Patients who received a single 8 Gy dose of RT for painful bone metastases were categorised into responders (n=36), non-responders (NR) (n=71). Saliva samples were sequenced to identify single-nucleotide variants (SNVs) in genes with known disease-causing variants from inflammation, radiation response, and DNA damage pathways. In univariate analysis, Cochran-Armitage trend tests were used to identify SNVs that associated with pain response (P<0.005), and the Penalized LASSO method with minimum Bayesian Information Criterion was used to identify multi-SNVs that jointly predict pain response to RT. The corresponding estimated effect of the multi-SNVs were used to drive the prognostic score for each patient. Based on it, patients were divided into 3 equal size risk groups. RESULTS: Forty-one significant variants were identified in univariate analysis. Multivariable analysis selected 14 variants to generate prognostic scores, adjusting for gender and primary cancer site. Eighty-nine percent of patients in the high prognostic group responded to palliative radiation therapy (P=0.0001). Estimated effect sizes of the variants ranged from 0.108-2.551. The most statistically significant variant was a deletion at position 111992032 in the ataxin gene ATXN2 (P=0.0001). Five variants were non-synonymous, including AOAH rs7986 (P=0.0017), ZAN rs539445 (P=0.00078) and rs542137 (P=0.00078), RAG1 rs3740955 (P=0.0014), and GBGT1 rs75765336 (P=0.0026). CONCLUSIONS: SNVs involved in mechanisms including DNA repair, inflammation, cellular adhesion, and cell signalling have significant associations with radiation response. SNVs with predictive power may stratify patient populations according to likelihood of responding to treatment, therefore enabling more efficient identification of beneficial strategies for pain management and improved resource utilisation.


Asunto(s)
Neoplasias Óseas/radioterapia , Dolor en Cáncer/genética , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Óseas/genética , Neoplasias Óseas/secundario , Dolor en Cáncer/prevención & control , Dolor en Cáncer/radioterapia , Femenino , Genes Relacionados con las Neoplasias/genética , Marcadores Genéticos/genética , Humanos , Masculino , Persona de Mediana Edad , Cuidados Paliativos/métodos , Saliva/química , Resultado del Tratamiento
5.
Ann Palliat Med ; 6(Suppl 2): S248-S256, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29156910

RESUMEN

BACKGROUND: Patients with bone metastases undergoing palliative radiation therapy (RT) may experience changes in both the functional and symptomatic aspects of quality of life (QOL). The European Organization of Cancer Research and Treatment (EORTC) QOL Questionnaire Core-15 Palliative (QLQ-C15-PAL) is a validated questionnaire employed to assess QOL specifically in palliative patients. Our study aimed to identify single-nucleotide variant (SNV) genetic biomarkers associated with changes in QOL and pain. METHODS: Fifty-two patients who received a single 8-Gy RT for painful bone metastases completed the EORTC QOL-C15-PAL questionnaire prior to randomization and at 42-day post RT. Saliva samples obtained at day of RT were sequenced, and SNVs from genes involved in inflammation, radiation response, immune response, DNA damage, or QOL were assessed for association with changes in global QOL or the pain scale items using the Cochran-Armitage trend test. The penalized LASSO method with minimum Bayesian information criterion was used to select a multi-SNV model out of significant SNVs (P<0.005) and to produce prognostic scores for patients that categorized them into risk groups of low, middle, and high. RESULTS: The multivariable model predicting global QOL included 14 SNVs, of which HS1BP3 rs35579164 G:C and ABCA1 rs2230805 C>T had the largest positive and negative effect sizes, respectively (HS1BP3: 8.21, ABCA1: -3.44). The model for the response of QOL pain item included 8 SNVs, of which PLAUR rs4760 A>G and ELAC2rs11545302 had the largest positive and negative effect sizes, respectively (PLAUR: 5.23; ELAC: -3.84). The patients' risk groups were highly predictive of QOL response (P<0.0001) and pain item response (P<0.0001). In logistic regression analysis accounting for baseline factors of gender and primary cancer site, the global QOL risk group predicts pain response after RT [OR: 2.1, 95% confidence interval (CI): 1.2-3.9, P=0.015], but the QOL pain item risk group did not (OR: 0.93; 95% CI: 0.5-1.6, P=0.79). The multi-SNVs model included SNVs from genes involved in metabolism, membrane transport, cell cycle control, ciliary structure, and gene expression regulation. CONCLUSIONS: SNVs were significantly associated with changes in global QOL of global domain and pain item in patients with bone metastases. Identification of genetic biomarkers predictive of QOL items may allow patients and health care providers anticipate and better address the needs of the palliative cancer patient population.


Asunto(s)
Neoplasias Óseas/radioterapia , Dolor en Cáncer/genética , Calidad de Vida , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos/uso terapéutico , Neoplasias Óseas/genética , Neoplasias Óseas/secundario , Dolor en Cáncer/prevención & control , Dolor en Cáncer/psicología , Método Doble Ciego , Femenino , Genes Relacionados con las Neoplasias/genética , Marcadores Genéticos/genética , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Cuidados Paliativos/métodos , Polimorfismo de Nucleótido Simple/genética , Saliva/química
6.
Ann Palliat Med ; 6(Suppl 2): S240-S247, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29156912

RESUMEN

BACKGROUND: In patients who receive palliative radiation therapy (RT) for painful bone metastases, 40% experience a transient increase in pain known as a pain flare. Prophylactic dexamethasone has been shown to reduce pain flare incidence to 25%. We aimed to identify DNA biomarkers associated with pain flare and dexamethasone response. METHODS: Daily pain levels were recorded by 81 patients who received a single 8 Gy RT for painful bone metastases, of which 50 also received prophylactic dexamethasone. To identify single-nucleotide variants (SNVs), patient saliva samples obtained at day of RT were sequenced for 4,813 disease-associated genes, then filtered for genes associated with inflammation, radiation or immune response, and DNA damage. Significant SNVs (P<0.005) identified by the Cochran-Armitage trend test underwent the Penalized LASSO method with minimum Bayesian Information Criterion to select a multi-SNV model that jointly predicted pain flare, and pain flare despite prophylactic dexamethasone (dexamethasone response). The corresponding estimated effects of the multi-SNVs were used to drive the prognostic score of developing pain flare for each patient, who were divided into three risk groups of roughly equal sizes. RESULTS: Risk groups were significantly predictive of pain flare (P<0.0001) and dexamethasone response (P<0.0001). The high-risk patient groups had a 78% chance of developing pain flare, and pain flare despite dexamethasone [OR =24.6, 95% confidence interval (CI): 1.8-342.7, P=0.02]. The multivariable model for pain flare included 15 variants, with effect sizes ranging from -4.97 (NBPF1 rs3872309 C>T) to 5.54 (DNM2 10940838 A>C). The multivariable model for dexamethasone response included 6 variants, with effect sizes ranging from -1.03 (NBPF1 rs3872309 C>T) to 0.85 (TSEN54 rs62088470 C>G). CONCLUSIONS: Significant SNVs associated with pain flare were found in genes with functions in biosynthesis (DHODH, PECR), lipid excretion and metabolism (UGT2A1/2, VLDLR), and intracellular signalling (DNM2, SEC23A). Significant SNVs associated with dexamethasone response were from genes involved in extracellular matrix (HAS1, ADAMTS16) and cytoskeleton regulation (GAS2L2). Identification of SNVs predictive of pain flare and dexamethasone response enables targeted prophylactic therapy according to a patient's predisposed response.


Asunto(s)
Antiinflamatorios/administración & dosificación , Neoplasias Óseas/radioterapia , Dolor en Cáncer/genética , Dexametasona/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Óseas/genética , Neoplasias Óseas/secundario , Dolor en Cáncer/prevención & control , Método Doble Ciego , Esquema de Medicación , Femenino , Genes Relacionados con las Neoplasias/genética , Marcadores Genéticos/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Cuidados Paliativos/métodos , Polimorfismo de Nucleótido Simple/genética , Radioterapia/efectos adversos , Saliva/química , Comprimidos , Resultado del Tratamiento
7.
BMJ Open ; 7(3): e015420, 2017 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-28363933

RESUMEN

INTRODUCTION: Delirium is highly prevalent in the intensive care unit (ICU) and is associated with adverse clinical outcomes. At this time, there is no drug that effectively prevents delirium in critically ill patients. Alterations in melatonin secretion and metabolism may contribute to the development of delirium. Administration of exogenous melatonin has been shown to prevent delirium in non-critically ill surgical and medical patients. This trial will demonstrate the feasibility of a planned multicentre, randomised controlled trial to test the hypothesis that melatonin can prevent delirium in critically ill patients compared with placebo. METHODS AND ANALYSIS: This feasibility trial is a randomised, 3-arm, placebo-controlled study of melatonin (2 vs 0.5 mg vs placebo, administered for a maximum of 14 days) for the prevention of delirium in critically ill patients. A total of 69 patients aged 18 years and older with an expected ICU length of stay >48 hours will be recruited from 3 Canadian ICUs. The primary outcome is protocol adherence (ie, overall proportion of study drug doses administered in the prescribed administration window). Secondary outcomes include pharmacokinetic parameters, incidence, time to onset, duration of delirium, number of delirium-free days, adverse events, self-reported sleep quality, rest-activity cycles measured by wrist actigraphy, duration of mechanical ventilation, ICU length of stay and mortality. Data will be analysed using an intention-to-treat approach. ETHICS AND DISSEMINATION: The study has been approved by Health Canada and the research ethics board of each study site. Trial results will be presented at international conferences and published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT02615340: Pre-results.


Asunto(s)
Depresores del Sistema Nervioso Central/uso terapéutico , Delirio/prevención & control , Melatonina/uso terapéutico , Adolescente , Adulto , Anciano , Depresores del Sistema Nervioso Central/farmacocinética , Enfermedad Crítica , Femenino , Humanos , Masculino , Cumplimiento de la Medicación , Melatonina/farmacocinética , Persona de Mediana Edad , Selección de Paciente , Proyectos Piloto , Resultado del Tratamiento , Adulto Joven
8.
BMJ Paediatr Open ; 1(1): e000074, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29637115

RESUMEN

OBJECTIVES: The primary objective was to establish reference intervals for laboratory tests used to assess iron status in young children using the Clinical and Laboratory Standards Institute guidelines. A secondary objective was to compare the lower limit of the reference interval with the currently recommended cut-off value for haemoglobin and serum ferritin in children 1-3 years of age. METHODS: Blood samples were obtained from healthy children recruited during scheduled health supervision visits with their primary care physician. For our primary objective, outliers were removed; age partitions were selected and analysis of variance and pairwise comparisons were made between adjacent partitions; reference intervals and 90% CIs were calculated. For our secondary objective, we determined the proportion of children misclassified using the lower limit reference interval compared with the cut-off value. RESULTS: Samples from 2305 male and 2029 female participants (10 days to 10.6 years) were used to calculate age and sex-specific reference intervals for laboratory tests of iron status. There were statistically significant differences between adjacent age partitions for most analytes. Approximately 10% of children 1-3 years of age were misclassified (underestimated) using the lower limit of the reference intervals rather than the currently recommended cut-off values for haemoglobin and serum ferritin. IMPLICATIONS AND RELEVANCE: Clinical laboratories may consider adopting published paediatric reference intervals. Reference intervals may misclassify (underestimate) children with iron deficiency as compared with currently recommended cut-off values. Future research on decision limits derived from clinical studies of outcomes is a priority.

9.
Ann Palliat Med ; 5(2): 107-15, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27121738

RESUMEN

BACKGROUND: External beam radiotherapy (EBRT) is a mainstay for treatment of painful bone metastases. Transient worsening of pain ("pain flare") occurs in 40% of patients. We investigated the pathophysiology of pain flare through assessment of changes in urinary cytokines/chemokines in patients receiving EBRT for painful bone metastases. METHODS: Urine samples were collected from patients receiving a single 8 Gy fraction for painful bone metastases preparation, day 1 or 2 and on an additional day between days 3 to 5 post radiation. Patients completed a standardized pain and analgesic use diary daily for 10 days following radiation. Patients were deemed to have pain flare if they had a two-point increase from baseline worst pain on 0-10 scale and no decrease in analgesic intake or a 25% increase in analgesic intake with no decrease in worst pain. The Millipore Milliplex 42-Plex Cyto-kine/Chemokine Kit™ was used to measure urinary levels of a panel of cytokines/chemokines. RESULTS: Forty-six patients consented to the study of which 28 were evaluable (complete urine and diary data), and 83/84 urine samples were available for analysis. Pain flare was experienced by 11 patients (39%). The following cytokines/chemokines were detectable in at least 50% of the patients: EGF, fractalkine, GRO, IL-4, IL-8, interferon gamma induced protein 10 (IP-10), MCP-1, macrophage derived chemokine (MDC), PDGF-AA, sIL-2Ra, TGF-Alpha, VEGF. Comparing patients with or without pain flare EGF, fractalkine, GRO, IL-8, IP-10, MCP-1, MDC, sIL-2Ra, and TGF-alpha increased following radiation in both groups. Patients with pain flare have significant lower levels on IL-8, IP-10, and MDC over time. No specific time trend was noticed. CONCLUSIONS: Patients who experience pain flare appear to have a different pattern in urinary cytokine/chemokine levels than patients without pain flare. A larger study is required to confirm the possible role of cytokines/chemokines in predisposition to and/or the cause of pain flare following radiation to painful bone metastases.


Asunto(s)
Neoplasias Óseas/radioterapia , Quimiocinas/orina , Citocinas/orina , Dolor/fisiopatología , Dolor/orina , Anciano , Anciano de 80 o más Años , Neoplasias Óseas/secundario , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor/etiología , Dimensión del Dolor , Radioterapia/efectos adversos , Radioterapia/métodos
10.
Radiother Oncol ; 115(1): 141-8, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25782738

RESUMEN

PURPOSE: The NCIC CTG Symptom Control.20 randomized trial (SC.20) confirmed the effectiveness of re-irradiation to painful bone metastases. This companion study correlates urinary markers of osteoclast activity with response to re-irradiation, survival and skeletal related events (SREs). METHODS: Pain response was assessed using the International Consensus Endpoints. Urinary markers of bone turnover-pyridinoline (PYD), deoxypyridinoline (DPD), N-telopeptide (NTX), Alpha and Beta cross-laps of C-telopeptide (CTX)-before and 1month after re-irradiation were correlated to response to re-irradiation and then to both, either or none of the initial and re-irradiation: frequent responders (response to both); eventual responders (response to re-irradiation only); eventual non-responders (response to initial radiation only), and absolute non-responders (no response to both). RESULTS: Significant differences between 40 responders and 69 non-responders to re-irradiation existed for PYD (p=0.03) and DPD (p=0.04) at baseline. When patients were categorized as frequent responders (N=34), eventual responders (6), eventual non-responders (59) and absolute non-responders (10), the mean values of all markers in the absolute non-responders at baseline and the follow-up were about double those for the other three groups with statistically significant difference for DPD (p=0.03) at baseline. Absolute non-responders had the worst survival. The few occurrences of the SREs did not allow meaningful comparisons among the groups. CONCLUSION: There were significant differences between responders and non-responders to re-irradiation for PYD and DPD at baseline. The urinary markers in the absolute non-responders were markedly elevated at both baseline and follow-up with a statistically significant difference for DPD at baseline.


Asunto(s)
Biomarcadores de Tumor/orina , Neoplasias Óseas/radioterapia , Osteoclastos/efectos de la radiación , Adulto , Anciano , Anciano de 80 o más Años , Aminoácidos/orina , Neoplasias Óseas/secundario , Colágeno Tipo I/orina , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Péptidos/orina
11.
J Chromatogr A ; 1367: 33-8, 2014 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-25305784

RESUMEN

A thin-film solid-phase microextraction (SPME) method coupled to liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis was developed for high-throughput determination of bronchoalveolar lavage bile acids. The proposed method was validated according to the bioanalytical method validation guidelines. LOQ and LLOQ were 0.007 and 0.02 µmol/L, respectively. The accuracy and the precision were <7 and <4%, respectively. The performance of the proposed method was also compared with an optimized enzymatic cycling assay. Results showed a weak correlation between total concentration of bile acid (BAs) obtained with enzymatic assay and cumulative concentration of specific BAs determined with SPME-LC-MS/MS. This discrepancy was probably due to the presence of other BAs in bronchoalveolar lavage fluid (BALF) samples. Metabolites profiling of BALF samples extracts using a high-resolution mass spectrometer (HRMS) revealed the presence of additional BAs, which were not included in the proposed method. After considering these additional BAs, a strong correlation was found between the LC-MS method and the enzymatic assay. Unsupervised statistical analysis conducted on HRMS data also showed clear separation within BALF samples, depending on the presence of BAs and other lipids. SPME-LC-MS-based metabolites profiling may provide additional information for diagnosis occurrence and severity of gastric reflux/aspiration in lung transplant patients.


Asunto(s)
Ácidos y Sales Biliares/análisis , Cromatografía Líquida de Alta Presión/métodos , Pruebas de Enzimas/métodos , Microextracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Ácidos y Sales Biliares/metabolismo , Lavado Broncoalveolar , Humanos , Reproducibilidad de los Resultados
12.
Eur Urol ; 66(6): 982-6, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25199720

RESUMEN

UNLABELLED: Molecular profiling of individual cancers is key to personalised medicine. While sequencing technologies have required stringent sample collection and handling, recent technical advances offer sequencing from tissues collected in routine practice and tissues already stored in archives. In this paper, we establish methods for whole-transcriptome RNA sequencing (RNA-seq) from formalin-fixed paraffin-embedded tissues. We obtain average RNA-seq reads of >100 million per sample using the Illumina HiSeq2000 platform. We find high concordance with results from matching fresh frozen samples (>0.8 Spearman correlation). For validation, we compared low- and high-grade bladder cancer transcriptomes in 49 tumour samples after transurethral resection of bladder tumour. We found 947 differentially expressed protein-coding genes. While high-grade lesions exhibited distinct intertumour transcriptome heterogeneity, the transcriptome of low-grade tumours was homogeneous. PATIENT SUMMARY: In this report, we show that it is now possible to use universally available bladder cancer samples that have been fixed in formalin to perform high-quality transcriptome analysis. This ability will facilitate the development of transcriptome-wide tests based on gene expression correlated with clinical outcome.


Asunto(s)
Perfilación de la Expresión Génica , Análisis de Secuencia de ARN/métodos , Neoplasias de la Vejiga Urinaria/genética , Fijadores , Formaldehído , Humanos , Clasificación del Tumor , Adhesión en Parafina , Manejo de Especímenes , Neoplasias de la Vejiga Urinaria/patología
13.
Lab Chip ; 12(14): 2560-7, 2012 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-22581052

RESUMEN

This paper reports a microfluidic system for biophysical characterization of red blood cells (RBCs) at a speed of 100-150 cells s(-1). Electrical impedance measurement is made when single RBCs flow through a constriction channel that is marginally smaller than RBCs' diameters. The multiple parameters quantified as mechanical and electrical signatures of each RBC include transit time, impedance amplitude ratio, and impedance phase increase. Histograms, compiled from 84,073 adult RBCs (from 5 adult blood samples) and 82,253 neonatal RBCs (from 5 newborn blood samples), reveal different biophysical properties across samples and between the adult and neonatal RBC populations. In comparison with previously reported microfluidic devices for single RBC biophysical measurement, this system has a higher throughput, higher signal to noise ratio, and the capability of performing multi-parameter measurements.


Asunto(s)
Eritrocitos/fisiología , Técnicas Analíticas Microfluídicas/instrumentación , Adulto , Impedancia Eléctrica , Electrodos , Eritrocitos/citología , Humanos , Recién Nacido , Técnicas Analíticas Microfluídicas/métodos
14.
Clin Rev Allergy Immunol ; 41(1): 20-35, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19997988

RESUMEN

Clinical multiplex diagnostic proteomics is the application of proteomic technologies to improve a patient's clinical outcomes. The future holds impact potential for testing prognosis, diagnosis, and drug therapy, while monitoring efficacious treatment with qualitative and quantitative data. Multiplex clinical diagnostic use of novel biomarkers in body fluids to confirm presence and severity of clinical disease states, holds great promise for clinical use. Challenges for diagnostic clinics include awareness of proteome complexity in clinical samples, the effects of high-abundance proteins, such as albumin, that could mask detection of other and low abundance disease proteins or biomarkers. Standardized approaches to sample collection and preparation, new analytical techniques and novel algorithms for bio-statistical analysis will facilitate release of the great potential of clinical multiplex diagnostic proteomics. A sensitive RA assay has been developed for the simultaneous measurement of the three rheumatoid factors (RFs), RF-IgA, IgG, and IgM, with the option to simultaneously measure anti-cyclic citrullinated peptide (anti-CCP) IgG antibodies using IgXPLEX™: technology. Testing 10-µL serum samples, SQI's multiplex microarray rheumatoid arthritis assay provides both positive/negative as well as qualitative/semi-quantitative results for anti-CCP IgG, RF-IgA, IgG, and IgM in each sample well on a 96-well microtiter-formatted microarray plate. Signal detection uses sensitive fluorescent-tagged markers captured onto planar microarray spots and read in a microarray scanner. Each result is verified with confidence confirmation technology and validating quality controls in every sample well. For an 80-RA positive patient cohort, the 4-PLEX profile sensitivity was determined at 82.5%. The specificity for the 44 RA healthy control cohort was determined at 97.7%. The multiplex data also demonstrated that a patients' severity of disease profile, mild to severe, correlates the status of RA biomarkers to disease status.


Asunto(s)
Artritis Reumatoide/diagnóstico , Pruebas Inmunológicas , Análisis por Micromatrices , Adolescente , Artritis Reumatoide/inmunología , Artritis Reumatoide/fisiopatología , Biomarcadores/sangre , Progresión de la Enfermedad , Ensayos Analíticos de Alto Rendimiento , Humanos , Inmunoglobulinas/sangre , Masculino , Microtecnología , Persona de Mediana Edad , Péptidos Cíclicos/inmunología , Pronóstico , Proteómica/instrumentación , Proteómica/métodos , Proteómica/tendencias , Reproducibilidad de los Resultados , Factor Reumatoide/sangre , Sensibilidad y Especificidad
15.
Int J Gynecol Pathol ; 28(2): 114-9, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19188825

RESUMEN

The histopathologic distinction of cervical adenocarcinoma in situ (AIS) and invasive adenocarcinoma (AC) from some benign endocervical lesions can be challenging. The ProEx C antibody reagent targets nuclear proteins (minichromosome maintenance protein 2, MCM2 and topoisomerase II-alpha, TOP2A), which are over expressed during the aberrant S-phase induction of HPV infected and neoplastic cells. In this immunohistochemical study the utility of the ProEx C reagent in distinguishing AIS and AC from a variety of non-neoplastic glandular lesions was examined. ProEx C immunohistochemical staining was performed on sections from formalin-fixed, paraffin-embedded tissue of 65 cervical tissues including 48 non-neoplastic cervices (normal [n=10], microglandular hyperplasia [n=10], tubal metaplasia [n=11], cervical endometriosis [n=7], reactive endocervix [n=10]) and 17 cervices with glandular malignancy (AIS [n=12] and AC [n=5]). Both intensity and prevalence of immunoreactivity was scored. The median and distribution of scores for both prevalence and intensity was compared for AIS versus each of the 5 benign cervical lesions using a Mann-Whitney U test. The median and distribution of prevalence of immunohistochemical staining for AIS was different from all benign mimics, but the intensity of staining for AIS did overlap with some mimics as it was not significantly different from endometriosis, microglandular hyperplasia, and reactive endocervix. ProEx C reagent has potential as an adjunctive testing tool in the histopathologic diagnosis of both AIS and AC, particularly in difficult cases with small biopsies or foci of disease.


Asunto(s)
Adenocarcinoma/diagnóstico , Antígenos de Neoplasias/biosíntesis , Proteínas de Ciclo Celular/biosíntesis , ADN-Topoisomerasas de Tipo II/biosíntesis , Proteínas de Unión al ADN/biosíntesis , Inmunohistoquímica/métodos , Proteínas Nucleares/biosíntesis , Displasia del Cuello del Útero/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Adenocarcinoma/metabolismo , Biomarcadores de Tumor/análisis , Femenino , Humanos , Hiperplasia/diagnóstico , Hiperplasia/metabolismo , Componente 2 del Complejo de Mantenimiento de Minicromosoma , Proyectos Piloto , Proteínas de Unión a Poli-ADP-Ribosa , Juego de Reactivos para Diagnóstico , Neoplasias del Cuello Uterino/metabolismo , Displasia del Cuello del Útero/metabolismo
16.
J Alzheimers Dis ; 14(1): 69-84, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18525129

RESUMEN

Dysregulation of iron homeostasis is implicated in Alzheimer's disease (AD). In this pilot study, common variants of the apolipoprotein E (APOE) and HFE genes resulting in the iron overload disorder of hereditary hemochromatosis (C282Y, H63D and S65C) were evaluated as factors in sporadic AD in an Ontario sample in which folic acid fortification has been mandatory since 1998. Laboratory studies also were done to search for genetic effects on blood markers of iron status, red cell folates and serum B12. Participants included 58 healthy volunteers (25 males, 33 females) and 54 patients with probable AD (20 males, 34 females). Statistical analyses were interpreted at the 95% confidence level. Contingency table and odds ratio analyses supported the hypothesis that in females of the given age range, E4 significantly predisposed to AD in the presence but not absence of H63D. In males, E4 significantly predisposed to AD in the absence of H63D, and H63D in the absence of E4 appeared protective against AD. Among E4+ AD patients, H63D was associated with significant lowering of red cell folate concentration, possibly as the result of excessive oxidative stress. However, folate levels in the lowest population quartile did not affect the risk of AD. A model is presented to explain the experimental findings.


Asunto(s)
Alelos , Enfermedad de Alzheimer/genética , Apolipoproteína E4/genética , Análisis Mutacional de ADN , Ácido Fólico/administración & dosificación , Variación Genética/genética , Hemocromatosis/genética , Antígenos de Histocompatibilidad Clase I/genética , Sobrecarga de Hierro/genética , Proteínas de la Membrana/genética , Anciano de 80 o más Años , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/tratamiento farmacológico , Biomarcadores/sangre , Eritrocitos/metabolismo , Femenino , Ácido Fólico/sangre , Predisposición Genética a la Enfermedad/genética , Genotipo , Hemocromatosis/sangre , Proteína de la Hemocromatosis , Humanos , Sobrecarga de Hierro/sangre , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Ontario , Factores Sexuales , Vitamina B 12/sangre
17.
Cancer Res ; 66(20): 10213-9, 2006 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-17047087

RESUMEN

Sun exposure is associated with lower death rates for pancreatic cancer in some ecological studies. Skin exposure to UVB light induces cutaneous production of precursors to 25-hydroxyvitamin D [25(OH)D]. Pancreatic islet and duct cells express 25(OH)D(3)-1alpha-hydroxylase that generates the biologically active 1,25(OH)(2) vitamin D form. Thus, 25(OH)D concentrations could affect pancreatic function and possibly pancreatic cancer etiology. We conducted a prospective nested case-control study in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention cohort of male Finnish smokers, ages 50 to 69 years at baseline, to test whether more adequate vitamin D status, as determined by prediagnostic serum 25(OH)D concentrations, was associated with lower pancreatic cancer risk. Two hundred incident exocrine pancreatic cancer cases that occurred between 1985 and 2001 (up to 16.7 years of follow-up) were matched by age and date of blood draw to 400 controls who were alive and free of cancer at the time the case was diagnosed. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated using conditional logistic regression. Higher vitamin D concentrations were associated with a 3-fold increased risk for pancreatic cancer (highest versus lowest quintile, >65.5 versus <32.0 nmol/L: OR, 2.92; 95% CI, 1.56-5.48, P(trend) = 0.001) that remained after excluding cases diagnosed early during follow-up. Contrary to expectations, subjects with higher prediagnostic vitamin D status had an increased pancreatic cancer risk compared with those with lower status. Our findings need to be replicated in other populations and caution is warranted in their interpretation and implication. Our results are intriguing and may provide clues that further the understanding of the etiology of this highly fatal cancer.


Asunto(s)
Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/etiología , Fumar/efectos adversos , Vitamina D/análogos & derivados , Anciano , Estudios de Casos y Controles , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Fumar/sangre , Vitamina D/sangre
18.
Can J Psychiatry ; 51(6): 382-6, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16786820

RESUMEN

OBJECTIVE: To compare the insulin sensitivity and adiponectin levels of medication-free patients suffering from schizophrenia or schizoaffective disorder with that of matched healthy volunteers. METHOD: We evaluated 9 nondiabetic patients aged 26.6 years (median 26 years, range 17 to 41 years) and matched volunteers, using the frequently sampled intravenous glucose tolerance test, minimal model analysis, and fasting adiponectin levels. RESULTS: The mean insulin sensitivity index of the patients was 42% lower than that of the healthy volunteers (P = 0.026), with inadequate compensation in insulin secretion. Patients with schizophrenia tended to have reduced adiponectin levels (P = 0.055). CONCLUSIONS: By direct measurement, this study provides evidence of insulin resistance and susceptibility to type 2 diabetes in patients with schizophrenia who are free of antipsychotic drugs.


Asunto(s)
Adiponectina/sangre , Resistencia a la Insulina/fisiología , Esquizofrenia/sangre , Adolescente , Adulto , Comorbilidad , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Masculino , Ontario , Factores de Riesgo , Esquizofrenia/diagnóstico , Esquizofrenia/epidemiología
19.
Clin Biochem ; 37(7): 642-6, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15234245

RESUMEN

Genomic biomarkers are an emerging class of laboratory tests, which present special implementation challenges for clinical laboratory services, compared to conventional laboratory tests. These challenges, which include analytical, bioinformatics, bioethical, interpretation and commercialization issues, represent real obstacles to widespread implementation of these tests. Technical challenges include the capacity to detect and identify many different kinds of markers for different diseases in a short time period, capacity to identify simultaneously gene rearrangements, amplification, inhibition, deletions and replications. Bioinformatics challenges include rapid analysis of genomic data, as well as the cross reference to other genomic data, and to other laboratory tests. Bioethical issues relate to consent to retain and use genetic data, which may be obtained inadvertently during analysis for genomic markers. Interpretation challenges include observations that the particular genomic markers may not be independent variables, as other undetected genomic alterations could invalidate or alter genomic marker interpretation. Further, as early experience with predictive genetic markers for cancer has shown, proprietary commercial interests may conflict with public health values of identifying genomic markers in subject populations. Based on our 10 years of experience with genomic biomarkers, important implementation strategies for genomic markers include development of:Standard high throughput analyzers capable of detecting any alteration of any genomic variant at any time. Bioinformatics analysis online, coupled to stored patient data. Laboratory service framework that preserves confidentiality but integrates genomic data with other laboratory tests. Laboratory service framework, which links consents, genomic analysis, reports to both specimen and data repositories. Overall, the laboratory service challenges for genomic markers are to manage very large analytical sets and very large data sets in finite time with responsible interpretation, all within finite funding. To meet these challenges, implementation strategies beyond the one disease, one diagnosis, one genomic marker concept must begin now.


Asunto(s)
Biomarcadores de Tumor/análisis , Técnicas de Laboratorio Clínico , Genómica , Neoplasias/diagnóstico , Neoplasias/genética , Humanos , Neoplasias/metabolismo
20.
J Clin Invest ; 109(6): 735-43, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11901182

RESUMEN

Increased inducible nitric oxide synthase (iNOS) expression is a component of the immune response and has been demonstrated in cardiomyocytes in septic shock, myocarditis, transplant rejection, ischemia, and dilated cardiomyopathy. To explore whether the consequences of such expression are adaptive or pathogenic, we have generated a transgenic mouse model conditionally targeting the expression of a human iNOS cDNA to myocardium. Chronic cardiac-specific upregulation of iNOS in transgenic mice led to increased production of peroxynitrite. This was associated with a mild inflammatory cell infiltrate, cardiac fibrosis, hypertrophy, and dilatation. While iNOS-overexpressing mice infrequently developed overt heart failure, they displayed a high incidence of sudden cardiac death due to bradyarrhythmia. This dramatic cardiac phenotype was rescued by specific attenuation of transgene activity. These data implicate cardiomyocyte iNOS overexpression as sufficient to cause cardiomyopathy, bradyarrhythmia, and sudden cardiac death.


Asunto(s)
Muerte Súbita Cardíaca/etiología , Bloqueo Cardíaco/metabolismo , Miocardio/enzimología , Óxido Nítrico Sintasa/metabolismo , Ácido Peroxinitroso/metabolismo , Acetilcolinesterasa/metabolismo , Animales , Nodo Atrioventricular/citología , Conexinas/metabolismo , Doxiciclina/metabolismo , Ecocardiografía , Regulación Enzimológica de la Expresión Génica , Humanos , Ratones , Ratones Transgénicos , Miocardio/citología , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa de Tipo II , Regiones Promotoras Genéticas , Análisis de Supervivencia , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismo , Proteína alfa-5 de Unión Comunicante
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