Rapid Point-of-Care Test for Determination of C-Peptide Levels.

C-peptide is co-secreted with insulin and is not subject to hepatic clearance and thus reflects functional β-cell mass. Assessment of C-peptide levels can identify individuals at risk for or with type 1 diabetes with residual β-cell function in whom β cell-sparing interventions can be evaluated, and can aid in distinguishing type 2 diabetes from Latent Autoimmune Diabetes in Adults and late-onset type 1 diabetes. To facilitate C-peptide testing, we describe a quantitative point-of-care C-peptide test.

Maternal serum glycosylated fibronectin as a short-term predictor of preeclampsia: a prospective cohort study.

Background: Preeclampsia is a major pregnancy complication that results in significant maternal and infant mortality, most of which occurs in low and middle-income countries. The accurate and timely diagnosis of preeclampsia is critical in management of affected pregnancies to reduce maternal and fetal/neonatal morbidity and mortality, yet difficulties remain in establishing the rigorous diagnosis of preeclampsia based on clinical parameters alone. Biomarkers that detect biochemical disease have been proposed as complements or alternatives to clinical criteria to improve diagnostic accuracy.

Maternal serum biomarkers for risk assessment in gestational diabetes. A potential universal screening test to predict GDM status.

The prevalence of gestational diabetes mellitus (GDM) is increasing because of the worldwide obesity/diabetes epidemic. The complications of untreated GDM affect both the mother and baby and include complications during pregnancy as well as increased risk of subsequent type-2 diabetes in mothers and offspring. Standard tests for hyperglycemia in diabetes, such as fasting glucose and hemoglobin (HbA1c), are currently not recommended for GDM screening.

Salivary protein glycosylation as a noninvasive biomarker for assessment of glycemia.

Assessment of short-term glycemic control can facilitate monitoring of diabetes development in at-risk individuals and monitoring response to lifestyle modification or medication. We evaluated salivary protein glycosylation levels as a novel, noninvasive, short-term glycemic index in comparison to hemoglobin A1c (HbA1c), fructosamine, 1,5-anhydroglucitol (1,5-AG), and continuous glucose monitoring (CGM). Ten subjects with type 2 diabetes were monitored by CGM and saliva and blood were collected at baseline and days 1, 7, 14, 21, and 28 for determination of salivary protein glycosylation, serum fructosamine, and serum 1,5-anhydroglucitol (1,5-AG) levels, as well as HbA1c (baseline and day 28).

Maternal serum glycosylated fibronectin as a point-of-care biomarker for assessment of preeclampsia.

Objective: We assessed the association of glycosylated fibronectin (GlyFn) with preeclampsia and its performance in a point-of-care (POC) test.

Study Design: GlyFn, placental growth factor (PlGF), and soluble vascular endothelial growth factor receptor 1 (sFlt1) levels were determined in serum samples from 107 pregnant women. In all, 45 were normotensive and 62 were diagnosed with preeclampsia.

Proteomic analysis of cervical vaginal fluid proteins among women in recurrent preterm labor.

Objective: Proteomic analysis of four cervical-vaginal fluid (CVF) proteins to identify biomarkers of recurrent preterm birth (rPTB) in at-risk women prior to onset of preterm labor.

Methods: Nested case control study from 2007 to 2011 of women with prior spontaneous preterm birth(s) (PTB) who underwent serial CVF sampling. Mass spectrometry analysis was used and ELISA analysis was performed to validate candidates.

Glycosylated fibronectin as a first-trimester biomarker for prediction of gestational diabetes.

Objective: To evaluate the potential clinical utility of serum biomarkers for first-trimester prediction of gestational diabetes mellitus (GDM).

Methods: Maternal serum concentrations of glycosylated (Sambucus nigra lectin-reactive) fibronectin, adiponectin, sex hormone-binding globulin, placental lactogen, and high-sensitivity C-reactive protein (CRP) were measured at 5-13 weeks of gestation in a case-control study of 90 pregnant women with subsequent development of GDM and in 92 control group participants. Ability to detect GDM was assessed using logistic regression modeling and receiver operating characteristic (ROC) curves.

Excessive ovarian production of nerve growth factor elicits granulosa cell apoptosis by setting in motion a tumor necrosis factor α/stathmin-mediated death signaling pathway.

Excessive nerve growth factor (NGF) production by the ovary, achieved via a transgenic approach, results in arrested antral follicle growth, reduced ovulatory capacity, and a predisposition to cyst formation in response to mildly elevated LH levels. Two salient features in these mutant mice (termed 17NF) are an elevated production of 17α-hydroxyprogesterone (17-OHP(4)), testosterone, and estradiol (E(2)) in response to gonadotropins, and an increased frequency of granulosa cell (GC) apoptosis. In this study, we show that the increase in steroidal response is associated with enhanced expression of Cyp17a1, Hsd17b, and Cyp19a1, which encode the enzymes catalyzing the synthesis of 17-OHP(4), testosterone, and E(2) respectively.

Comprehensive maternal serum proteomic profiles of preclinical and clinical preeclampsia.

We systematically characterized maternal serum proteome in women with clinical preeclampsia (PE) and asymptomatic women in early pregnancy that subsequently developed PE. Clinical PE cohort comprised 30 patients with mild PE, 30 with severe PE, and 58 normotensive women. Preclinical PE cohort included 149 women whose serum samples were collected at 8-14 gestational weeks and in whom 30 women later developed mild and 40 severe PE.

Noninvasive diagnosis of intraamniotic infection: proteomic biomarkers in vaginal fluid.

Objective: We analyzed the vaginal fluid proteome to identify biomarkers of intraamniotic infection among women in preterm labor.

Study Design: Proteome analysis was performed on vaginal fluid specimens from women with preterm labor, using multidimensional liquid chromatography, tandem mass spectrometry, and label-free quantification. Enzyme immunoassays were used to quantify candidate proteins.

Insights into the multifactorial nature of preterm birth: proteomic profiling of the maternal serum glycoproteome and maternal serum peptidome among women in preterm labor.

Objective: The purpose of this study was to identify peptide classifiers that predict spontaneous preterm birth (SPTB) among women in preterm labor (PTL) and to demonstrate specific protein pathways that are activated in PTL.

Study Design: Serum from 110 women with PTL between 20 weeks and 33 weeks 6 days of gestation was subjected to glycoprotein purification, matrix-assisted laser desorption ionization time-of-flight mass spectrometry peptide profiling, 2-dimensional liquid chromatography tandem mass spectrometry, and pathway analysis. Women were divided into 2 groups: delivery at <34 weeks' gestation (SPTB group) and delivery at > or =34 weeks' gestation (PTL group).

Quantification of isotopically overlapping deamidated and 18o-labeled peptides using isotopic envelope mixture modeling.

A robust peptide quantification method was developed where overlapping peptide isotopic distributions were fit with predicted peptide isotopic envelope mixture models (IEMMs). Application to two difficult quantitative problems was demonstrated. The first was the quantification of deamidation, where masses of isotopic peaks differ by 1 Da, and the second was (18)O labeling, where the isotopic peaks are shifted 2 and 4 Da.

Proteomic identification of salivary biomarkers of type-2 diabetes.

The identification of biomarkers to noninvasively detect prediabetes/diabetes will facilitate interventions designed to prevent or delay progression to frank diabetes and its attendant complications. The purpose of this study was to characterize the human salivary proteome in type-2 diabetes to identify potential biomarkers of diabetes. Whole saliva from control and type-2 diabetic individuals was characterized by multidimensional liquid chromatography/tandem mass spectrometry (2D-LC-MS/MS).

Reliable detection of deamidated peptides from lens crystallin proteins using changes in reversed-phase elution times and parent ion masses.

Identifying deamidated peptides using low-resolution mass spectrometry is difficult because traditional database search programs cannot accurately detect modified peptides when the mass differences are only 0.984 Da. In this study, we utilized differential reversed-phase elution behavior of deamidated and corresponding unmodified peptide forms to significantly improve deamidation detection on a low-resolution LCQ ion trap instrument.

Comprehensive proteomic analysis of the human amniotic fluid proteome: gestational age-dependent changes.

Amniotic fluid (AF) is a significant contributor to fetal health and constitutes a potential rich source of biomarkers for diagnosis of maternal and fetal disorders. In this study, we performed a comprehensive survey of the proteins expressed in AF, combining gel and liquid-based fractionation approaches coupled with LC-MS/MS analysis. Two-dimensional Liquid Chromatography (2D-LC) analysis identified 118 nonredundant proteins with high confidence.

Identification of novel protein biomarkers of preterm birth in human cervical-vaginal fluid.

Spontaneous preterm birth (SPTB) is a major contributor to perinatal morbidity and mortality. However, the diagnosis of preterm labor (PTL) that leads to preterm birth is difficult, and there is a pressing need for improved diagnosis. We utilized multidimensional liquid chromatography-tandem mass spectrometry (LC/LC-MS/MS; MudPIT) and Fluorescence two-dimensional differential in-gel electrophoresis (2D-DIGE) to identify potential biomarkers of PTL and SPTB.

Comprehensive proteomic analysis of human cervical-vaginal fluid.

Cervical-vaginal fluid (CVF) is a potential rich source of biomarkers for enhancing our understanding of human parturition and pathologic conditions affecting pregnancy. In this study, we performed a comprehensive survey of the CVF proteome in pregnancy utilizing multidimensional liquid chromatography (2D-LC) coupled with mass spectrometry and gel-electrophoresis-based protein separation and identification. In total, 150 unique proteins were identified using multiple protein identification algorithms.

Proteomic analysis of maternal serum in down syndrome: identification of novel protein biomarkers.

Down syndrome (DS) is the most prevalent chromosomal disorder, accounting for significant morbidity and mortality. Definitive diagnosis requires invasive amniocentesis, and current maternal serum-based testing requires a false-positive rate of about 5% to detect 85% of affected pregnancies. We have performed a comprehensive proteomic analysis to identify potential serum biomarkers to detect DS.

Proteomic identification of urinary biomarkers of diabetic nephropathy.

Objective: Diabetic nephropathy is a serious complication of both type 1 and type 2 diabetes, and, unless arrested, leads to end-stage renal disease. Current diagnosis consists of urine assays of microalbuminuria, which have inadequate specificity and sensitivity.

Research Design And Methods: We used proteomic analyses to identify novel biomarkers of nephropathy in urine from type 2 diabetic patients with demonstrated normo-, micro-, or macroalbuminuria.

Large-scale generation of highly enriched neural stem-cell-derived oligodendroglial cultures: maturation-dependent differences in insulin-like growth factor-mediated signal transduction.

Multipotent neural stem cells (NSCs) are competent for commitment to the oligodendrocyte (OL) lineage both in vitro and in vivo. We exploited this property to develop a rat neurospheres (NS)/oligospheres (OS)-based culture system to generate large numbers of highly enriched late OL progenitors (preOLs) and mature OLs (MatOLs). CNS neuroblastoma cell line B104-derived conditioned medium promoted the generation of nearly pure populations of preOLs from dissociated OS.

Proteomic analysis of cervical-vaginal fluid: identification of novel biomarkers for detection of intra-amniotic infection.

Intra-amniotic infection (IAI) is associated with preterm birth and perinatal mortality. To identify potential biomarkers, we performed a comprehensive survey of the cervical-vaginal fluid (CVF) proteome from a primate IAI model utilizing multidimensional protein identification technology (LC/LC-MS/MS) and MALDI-TOF-MS analyses. Analyses of CVF proteome identified 205 unique proteins and differential expression of 27 proteins in controls and IAI samples.

A novel EWS-WT1 gene fusion product in desmoplastic small round cell tumor is a potent transactivator of the insulin-like growth factor-I receptor (IGF-IR) gene.

Desmoplastic small round cell tumor (DSRCT) is a primitive sarcoma characterized by a recurrent chromosomal translocation, t(11;22)(p13;q12), which fuses the 5' exons of the EWS gene to the 3' exons of the WT1 gene. EWS-WT1 chimeras are heterogeneous as a result of fusions of different regions of the EWS gene to the WT1 gene. We report here a rare and novel EWS-WT1 variant, EWS-WT1 5/10, in a 6-year-old boy diagnosed with DSRCT and analyze the potential transactivation effect of the fusion oncoprotein.

Proteomic profiling of mature CD10+ B-cell lymphomas.

Proteomic profiling with protein-chip technology has been used successfully to discover biomarkers with potential clinical usefulness in several cancer types. Little proteomic study has been done in B-cell lymphomas. We determined whether the expression of a set of proteins by protein-chip technology coupled with new informatics tools could be used to build a model to molecularly classify B-cell lymphoma subgroups.

Standardizing global gene expression analysis between laboratories and across platforms.

To facilitate collaborative research efforts between multi-investigator teams using DNA microarrays, we identified sources of error and data variability between laboratories and across microarray platforms, and methods to accommodate this variability. RNA expression data were generated in seven laboratories, which compared two standard RNA samples using 12 microarray platforms. At least two standard microarray types (one spotted, one commercial) were used by all laboratories.

Identification of protein modifications using MS/MS de novo sequencing and the OpenSea alignment algorithm.

Algorithms that can robustly identify post-translational protein modifications from mass spectrometry data are needed for data-mining and furthering biological interpretations. In this study, we determined that a mass-based alignment algorithm (OpenSea) for de novo sequencing results could identify post-translationally modified peptides in a high-throughput environment. A complex digest of proteins from human cataractous lens, a tissue containing a high abundance of modified proteins, was analyzed using two-dimensional liquid chromatography, and data was collected on both high and low mass accuracy instruments.