Plasma fatty acid esters of hydroxy fatty acids and surrogate fatty acid esters of hydroxy fatty acids hydrolysis activity in children with or without obesity and in adults with or without coronary artery disease.

AIM: Fatty acid esters of hydroxy fatty acids (FAHFA) are a class of bioactive lipids with anti-inflammatory, antidiabetic and cardioprotective properties. FAHFA hydrolysis into its fatty acid (FA) and hydroxy fatty acid (HFA) constituents can affect the bioavailability of FAHFA and its subsequent biological effects. We aimed to investigate FAHFA levels and FAHFA hydrolysis activity in children with or without obesity, and in adults with or without coronary artery disease (CAD). MATERIALS AND METHODS: Our study cohort included 20 children without obesity, 40 children with obesity, 10 adults without CAD and 28 adults with CAD. We quantitated plasma levels of four families of FAHFA [palmitic acid hydroxy stearic acid (PAHSA), palmitoleic acid hydroxy stearic acid (POHSA), oleic acid hydroxy stearic acid (OAHSA), stearic acid hydroxy stearic acid] and their corresponding FA and HFA constituents using liquid chromatography-tandem mass spectrometry analysis. Surrogate FAHFA hydrolysis activity was estimated as the FA/FAHFA or HFA/FAHFA ratio. RESULTS: Children with obesity had lower plasma PAHSA (p = .001), OAHSA (p = .006) and total FAHFA (p = .011) levels, and higher surrogate FAHFA hydrolysis activity represented by PA/PAHSA (p = .040) and HSA/OAHSA (p = .025) compared with children without obesity. Adults with CAD and a history of myocardial infarction (MI) had lower POHSA levels (p = .026) and higher PA/PAHSA (p = .041), POA/POHSA (p = .003) and HSA/POHSA (p = .038) compared with those without MI. CONCLUSION: Altered FAHFA metabolism is associated with obesity and MI, and inhibition of FAHFA hydrolysis should be studied further as a possible therapeutic strategy in obesity and MI.

Real-world treatment patterns and quality of life among patients with locally advanced or metastatic urothelial carcinoma living in Saudi Arabia, South Korea, Taiwan, and Turkey.

OBJECTIVES: To evaluate demographic and clinical characteristics, treatment patterns, and quality of life in patients with locally advanced or metastatic urothelial carcinoma in Asia. METHODS: Data were drawn from the Adelphi Real World Metastatic Urothelial Carcinoma Disease Specific Programme™, a cross-sectional survey of medical oncologists/urologists and their adult patients in Saudi Arabia, South Korea, Taiwan, and Turkey. Exploratory patient-reported outcomes included the EQ-5D visual analog scale, European Organisation for Research and Treatment of Cancer Quality of Life of Patient Questionnaire global health, and Brief Pain Inventory. Analyses were descriptive. RESULTS: Overall, 175 physicians reported data for 988 patients. Mean (standard deviation) patient age was 66.3 (10.8) years, 77% were men, and 82% had bladder tumors at diagnosis. Of patients receiving first- (n = 988), second- (n = 290), and third-line (n = 87) treatments, 81%, 35%, and 59% received chemotherapy, respectively, and 17%, 63%, and 34% received programmed cell death protein 1/ligand 1 inhibitors, respectively. Patient-reported (n = 319) mean (standard deviation) EQ-5D visual analog scale score was 51.8 (15.6), European Organisation for Research and Treatment of Cancer Quality of Life of Patient Questionnaire global health status score was 44.6 (19.9), and Brief Pain Inventory score was 6.5 (1.9; n = 315). CONCLUSION: The most common first- and second-line treatments for locally advanced or metastatic urothelial carcinoma were chemotherapy and programmed cell death protein 1/ligand inhibitors, respectively. At third line, 10% of patients received best supportive care alone, underscoring an unmet need for effective third-line treatment options. Patients in all regions reported quality-of-life impairment.

Use of probiotics, prebiotics, and synbiotics in non-alcoholic fatty liver disease: A systematic review and meta-analysis.

BACKGROUND AND AIM: Patients with non-alcoholic fatty liver disease (NAFLD) exhibit compositional changes in their gut microbiome, which represents a potential therapeutic target. Probiotics, prebiotics, and synbiotics are microbiome-targeted therapies that have been proposed as treatment for NAFLD. We aim to systematically review the effects of these therapies in liver-related outcomes of NAFLD patients. METHODS: We conducted a systematic search in Embase (Ovid), Medline (Ovid), Scopus, Cochrane, and EBSCOhost from inception to August 19, 2022. We included randomized controlled trials (RCTs) that treated NAFLD patients with prebiotics and/or probiotics. We meta-analyzed the outcomes using standardized mean difference (SMD) and assessed study heterogeneity using Cochran's Q test and I2 statistics. Risk of bias was assessed using the Cochrane Risk-of-Bias 2 tool. RESULTS: A total of 41 (18 probiotics, 17 synbiotics, and 6 prebiotics) RCTs were included. Pooled data demonstrated that the intervention had significantly improved liver steatosis (measured by ultrasound grading) (SMD: 4.87; 95% confidence interval [CI]: 3.27, 7.25), fibrosis (SMD: -0.61 kPa; 95% CI: -1.12, -0.09 kPa), and liver enzymes including alanine transaminase (SMD: -0.86 U/L; 95% CI: -1.16, -0.56 U/L), aspartate transaminase (SMD: -0.87 U/L; 95% CI: -1.22, -0.52 U/L), and gamma-glutamyl transferase (SMD: -0.77 U/L; 95% CI: -1.26, -0.29 U/L). CONCLUSIONS: Microbiome-targeted therapies were associated with significant improvements in liver-related outcomes in NAFLD patients. Nevertheless, limitations in existing literature like heterogeneity in probiotic strains, dosage, and formulation undermine our findings. This study was registered with PROSPERO (CRD42022354562) and supported by the Nanyang Technological University Start-up Grant and Wang Lee Wah Memorial Fund.

Application of a physiologically based pharmacokinetic model of rivaroxaban to prospective simulations of drug-drug-disease interactions with protein kinase inhibitors in cancer-associated venous thromboembolism.

AIMS: Rivaroxaban is a viable anticoagulant for the management of cancer-associated venous thromboembolism (CA-VTE). A previously verified physiologically-based pharmacokinetic (PBPK) model of rivaroxaban established how its multiple pathways of elimination via both CYP3A4/2J2-mediated hepatic metabolism and organic anion transporter 3 (OAT3)/P-glycoprotein-mediated renal secretion predisposes rivaroxaban to drug-drug-disease interactions (DDDIs) with clinically relevant protein kinase inhibitors (PKIs). We proposed the application of PBPK modelling to prospectively interrogate clinically significant DDIs between rivaroxaban and PKIs (erlotinib and nilotinib) for dose adjustments in CA-VTE. METHODS: The inhibitory potencies of the PKIs on CYP3A4/2J2-mediated metabolism of rivaroxaban were characterized. Using prototypical OAT3 inhibitor ketoconazole, in vitro OAT3 inhibition assays were optimized to ascertain the in vivo relevance of derived transport inhibitory constants (Ki ). Untested DDDIs between rivaroxaban and erlotinib or nilotinib were simulated. RESULTS: Mechanism-based inactivation (MBI) of CYP3A4-mediated rivaroxaban metabolism by both PKIs and MBI of CYP2J2 by erlotinib were established. The importance of substrate specificity and nonspecific binding to derive OAT3-inhibitory Ki values of ketoconazole and nilotinib for the accurate prediction of interactions was illustrated. When simulated rivaroxaban exposure variations with concomitant erlotinib and nilotinib therapy were evaluated using published dose-exposure equivalence metrics and bleeding risk analyses, dose reductions from 20 to 15 and 10 mg in normal and mild renal dysfunction, respectively, were warranted. CONCLUSION: We established a PBPK-DDDI model to prospectively evaluate clinically relevant interactions between rivaroxaban and PKIs for the safe and efficacious management of CA-VTE.

Relationships between developmental strategies for additional indications and price revisions for anticancer drugs in Japan.

BACKGROUND: The relationships between developmental strategies for additional indications and drug price revisions have not been thoroughly studied. Here, we investigated the price revisions for anticancer drugs approved in Japan. METHODS: The study was based on published information on anticancer drugs approved between January 2009 and March 2020 in Japan. We investigated the relationships between the pharmacological and regulatory characteristics of anticancer drugs and occurrence/non-occurrence of the Japanese National Health Insurance (NHI) price revisions. RESULTS: Eighty-one new anticancer drugs were given NHI price listings during the survey. On April 1, 2020, the prices of 23 anticancer drugs had been revised from the initial pricing, the prices were reduced for 21 drugs (91.3%). Several parameters showed the relationships between drug characteristics and NHI price revisions. The achievement of additional indications and compound type were identified as explanatory factors for these relationships. Additional indication profiles were defined to assess the relationships between the methods for additional indication achievement and price revisions. When the type of additional indication was "Expansion", the percentage of drugs received NHI price revisions was the highest (P<0.001). CONCLUSIONS: NHI price revision was significantly related to the achievement of additional indications and compound type. The strategy for additional indications was found to affect the occurrence/non-occurrence of NHI price revisions.

Assessment of posterior tongue mobility using lingual-palatal suction: Progress towards a functional definition of ankyloglossia.

BACKGROUND: A functional definition of ankyloglossia has been based on assessment of tongue mobility using the tongue range of motion ratio (TRMR) with the tongue tip extended towards the incisive papilla (TIP). Whereas this measurement has been helpful in assessing for variations in the mobility of the anterior one-third of the tongue (tongue tip and apex), it may be insufficient to adequately assess the mobility of the posterior two-thirds body of the tongue. A commonly used modification is to assess TRMR while the tongue is held in suction against the roof of the mouth in lingual-palatal suction (LPS). OBJECTIVE: This study aims to explore the utility and normative values of TRMR-LPS as an adjunct to functional assessment of tongue mobility using TRMR-TIP. STUDY DESIGN: Cross-sectional cohort study of 611 subjects (ages: 3-83 years) from the general population. METHODS: Measurements of tongue mobility using TRMR were performed with TIP and LPS functional movements. Objective TRMR measurements were compared with subjective self-assessment of resting tongue position, ease or difficulty elevating the tongue tip to the palate, and ease or difficulty elevating the tongue body to the palate. RESULTS: There was a statistically significant association between the objective measures of TRMR-TIP and TRMR-LPS and subjective reports of tongue mobility. LPS measurements were much more highly correlated with differences in elevating the posterior body of the tongue as compared to TIP measurements (R2 0.31 vs 0.05, P < .0001). CONCLUSIONS: This study validates the TRMR-LPS as a useful functional metric for assessment of posterior tongue mobility.

Synchronized abdominal compression as a novel treatment of life-threatening preschool asthma.

Introduction: In severe asthma, management of life-threatening air trapping that persists despite initiation of standard asthma treatment is difficult in the absence of extracorporeal membranous oxygenation.Case study: Three children with life-threatening asthma could not be adequately ventilated despite maximum conventional treatment because of severe air trapping. A novel method of active expiration by abdominal compression with a standard ventilator was adopted with immediate effect with significant improvement in ventilation.Conclusion: Synchronized abdominal compression is a novel and simple method that allows an effective treatment of severe air trapping in an intubated paralyzed asthma child.

Screening for anaplastic lymphoma kinase (ALK) gene rearrangements in non-small-cell lung cancer in New Zealand.

BACKGROUND: Lung cancer is a major cause of death in New Zealand. In recent years, targeted therapies have improved outcomes. AIM: To determine the uptake of anaplastic lymphoma kinase (ALK) testing, and the prevalence, demographic profile and outcomes of ALK-positive non-small-cell lung cancer (NSCLC), in New Zealand, where no national ALK-testing guidelines or subsidised ALK tyrosine kinase inhibitor (TKI) therapies are available. METHODS: A population-based observational study reviewed databases to identify patients presenting with non-squamous NSCLC over 6.5 years in northern New Zealand. We report the proportion tested for ALK gene rearrangements and the results. NSCLC samples tested by fluorescence in situ hybridisation were retested by next generation sequencing and ALK immunohistochemistry. A survival analysis compared ALK-positive patients treated or not treated with ALK TKI therapy. RESULTS: From a total of 3130 patients diagnosed with non-squamous NSCLC, 407 (13%) were tested for ALK gene rearrangements, and patient selection was variable and inequitable. Among those tested, 34 (8.4%) had ALK-positive NSCLC. ALK-positive disease was more prevalent in younger versus older patients, non-smokers versus smokers and in Maori, Pacific or Asian ethnic groups than in New Zealand Europeans. Fluorescence in situ hybridisation, ALK immunohistochemistry and next generation sequencing showed broad concordance for detecting ALK-positive disease under local testing conditions. Among patients with ALK-positive metastatic NSCLC, those treated with ALK TKI survived markedly longer than those not treated with ALK TKI (median overall survival 5.12 vs 0.55 years). CONCLUSION: Lung cancer outcomes in New Zealand may be improved by providing national guidelines and funding policy for ALK testing and access to subsidised ALK TKI therapy.

Orthodontic plate for management of obstructive sleep apnoea in infants with Pierre Robin sequence: experience and protocol in Hong Kong.

OBJECTIVE: To present the application of the pre-epiglottic baton plate (PEBP) in infants with Pierre Robin sequence (PRS) in the Southern Chinese population (Hong Kong) and to present the diagnosis and management protocol of these infants in our centre. DESIGN: Retrospective case series of three patients with PRS. SETTING: Neonatal Intensive Care Unit in Kwong Wah Hospital and Craniofacial Orthodontic Centre in United Christian Hospital, Hong Kong. PARTICIPANTS: Three new-born infants (two girls, one boy) with PRS and upper airway obstruction due to glossoptosis. METHODS: A protocol for the diagnosis and management of these infants in the Southern Chinese population (Hong Kong) was presented. The three patients received nasal high-flow oxygen and/or continuous positive airway pressure (CPAP) as first-line respiratory support, followed by PEBP for 3-5 months. A two-stage approach was undertaken to ensure accurate positioning of the PEBP. RESULTS: All three infants had improvement in clinical signs, symptoms and polysomnography upon discharge. PEBP and other respiratory aids were weaned off at 3-6 months. CONCLUSIONS: The PEBP, combined with other respiratory support, is a useful modality in the treatment of obstructive sleep apnoea in infants with PRS.

A prospective study of elderly initiating mirabegron versus antimuscarinics: Patient reported outcomes from the Overactive Bladder Satisfaction Scales and other instruments.

AIMS: To understand differences in patient reported outcomes (PRO) between patients initiating mirabegron or an antimuscarinic using a validated PRO instrument, OAB-Satisfaction (OAB-S). METHODS: This prospective observational study used real-time prescription claims from Humana to identify Medicare patients initiating mirabegron or an antimuscarinic to participate in a series of three phone surveys over ninety days. RESULTS: A total of 1897 mirabegron and 2444 randomly selected antimuscarinic initiators were identified; 174 mirabegron and 193 antimuscarinic initiators completed all three surveys. Among responders, mirabegron initiators were slightly older (76 vs 75 years, P = 0.032), included more males (32% vs 23%, P = 0.044), more likely to have prior OAB treatment (21% vs 13%, P = 0.048), and had greater medication burden (number of unique medications: 10.0 vs 8.7, P = 0.014). There were no between-group differences at any time or on any OAB-S scale. There were significant within-group differences at follow-up compared to baseline for OAB-S scales: "impact on daily living," with improvement over the 90-day survey period for both mirabegron (P = 0.008) and antimuscarinic (P < 0.001); "interruption of day-to-day life," with improvement for both mirabegron (P < 0.001) and antimuscarinic (P < 0.001); and improvement in "OAB control" for mirabegron (P < 0.001) and antimuscarinic (P < 0.001). CONCLUSIONS: Mirabegron initiators tended to be older, had a greater number of unique medications and previously tried prescriptions to treat OAB; nonetheless, mirabegron, and antimuscarinic initiators reported similar trends in improvement in PROs over the first 90 days of treatment. Significant improvement in daily impact of OAB was observed after treatment initiation; however, no significant differences between groups were observed.

Proteomic profiling of barley spent grains guides enzymatic solubilization of the remaining proteins.

Within the brewing industry, malted barley is being increasingly replaced by raw barley supplemented with exogenous enzymes to lessen reliance on the time-consuming, high water and energy cost of malting. Regardless of the initial grain of choice, malted or raw, the resultant bulk spent grains are rich in proteins (up to 25% dry weight). Efficient enzymatic solubilization of these proteins requires knowledge of the protein composition within the spent grains. Therefore, a comprehensive proteomic profiling was performed on spent grains derived from (i) malted barley (spent grain A, SGA) and (ii) enzymatically treated raw barley (spent grain B, SGB); data are available via ProteomeXchange with identifier PXD008090. Results from complementary shotgun proteomics and 2D gel electrophoresis showed that the most abundant proteins in both spent grains were storage proteins (hordeins and embryo globulins); these were present at an average of two fold higher in spent grain B. Quantities of other major proteins were generally consistent in both spent grains A and B. Subsequent in silico protein sequence analysis of the predominant proteins facilitated knowledge-based protease selection to enhance spent grain solubilization. Among tested proteases, Alcalase 2.4 L digestion resulted in the highest remaining protein solubilization with 9.2 and 11.7% net dry weight loss in SGA and SGB respectively within 2 h. Thus, Alcalase alone can significantly reduce spent grain side stream, which makes it a possible solution to increase the value of this low-value side stream from the brewing and malt extract beverage manufacturing industry.

Palivizumab for Infants < 29 Weeks in Hong Kong without a Clear-Cut Season for Respiratory Syncytial Virus Infection-A Cost-Effectiveness Analysis.

AIM: To evaluate the cost-effectiveness of palivizumab prophylaxis for premature infants born <29 weeks in Hong Kong. METHOD: We evaluated the hospitalization rate for respiratory syncytial virus (RSV) infection within the first 12 months of discharge of a cohort of preterm infants born between 2010 and 2014 at two local hospitals. RESULTS: In total, 40 of 135 infants were given palivizumab. The hospitalization rate for premature infants <29 weeks was reduced from 15.8 to 5% (p = 0.096) and that for infants <27 weeks was reduced from 33.3 to 8.7% (p = 0.046). In the former group, the incremental cost-effectiveness ratio per hospital admission prevented (ICER/HAP) was US dollar (USD) 24 365. In the latter subgroup, the ICER/HAP was USD 3108. CONCLUSION: The cost-effectiveness as measured for infants <27 weeks is more favorable than that for infants <29 weeks.

SNPs in KCNQ1 are associated with susceptibility to type 2 diabetes in East Asian and European populations.

We conducted a genome-wide association study using 207,097 SNP markers in Japanese individuals with type 2 diabetes and unrelated controls, and identified KCNQ1 (potassium voltage-gated channel, KQT-like subfamily, member 1) to be a strong candidate for conferring susceptibility to type 2 diabetes. We detected consistent association of a SNP in KCNQ1 (rs2283228) with the disease in several independent case-control studies (additive model P = 3.1 x 10(-12); OR = 1.26, 95% CI = 1.18-1.34). Several other SNPs in the same linkage disequilibrium (LD) block were strongly associated with type 2 diabetes (additive model: rs2237895, P = 7.3 x 10(-9); OR = 1.32, 95% CI = 1.20-1.45, rs2237897, P = 6.8 x 10(-13); OR = 1.41, 95% CI = 1.29-1.55). The association of these SNPs with type 2 diabetes was replicated in samples from Singaporean (additive model: rs2237895, P = 8.5 x 10(-3); OR = 1.14, rs2237897, P = 2.4 x 10(-4); OR = 1.22) and Danish populations (additive model: rs2237895, P = 3.7 x 10(-11); OR = 1.24, rs2237897, P = 1.2 x 10(-4); OR = 1.36).

USP6 gene rearrangement in nodular fasciitis and histological mimics.

AIMS: Nodular fasciitis is known to be a benign mimic of sarcoma, both clinically and histologically. Accurate diagnosis, particularly on small biopsies, remains a challenge, as the morphology can be varied and the immunophenotype is essentially non-specific. Recently, rearrangement of the ubiquitin-specific protease 6 (USP6) gene has been reported as a recurrent and specific finding in nodular fasciitis. The aim of this this study was to evaluate the diagnostic utility of USP6 fluorescence in-situ hybridization (FISH) analysis in a subset of spindle-cell proliferations in which nodular fasciitis enters into the differential diagnosis. METHODS AND RESULTS: A database search was performed at the Middlemore Hospital Histopathology Department. All in-house cases diagnosed between 2002 and March 2014 in which nodular fasciitis was considered as a differential diagnosis were retrospectively identified. Twenty cases were retrieved, reviewed and categorized as 'definite', 'possible' or 'definitely not' nodular fasciitis by consensus morphological opinion of three experienced pathologists. FISH analysis for USP6 rearrangement was performed in each case, with a commercially available break-apart probe. Of seven cases that were morphologically categorized as 'definite' nodular fasciitis, six were FISH-positive and one was FISH-negative. Of four cases categorized as 'possible' nodular fasciitis, one was FISH-positive and three were FISH-negative. Nine cases categorized as 'definitely not' nodular fasciitis were all FISH-negative. In the morphologically definitive cases, FISH analysis for USP6 had a sensitivity of 86% and specificity of 100% for a diagnosis of nodular fasciitis. The positive predictive value was 100%, and the negative predictive value 90%. CONCLUSIONS: USP6 FISH is a useful ancillary test in cases where nodular fasciitis is a potential diagnostic consideration.

A kinase interacting protein (AKIP1) is a key regulator of cardiac stress.

cAMP-dependent protein kinase (PKA) regulates a myriad of functions in the heart, including cardiac contractility, myocardial metabolism,and gene expression. However, a molecular integrator of the PKA response in the heart is unknown. Here, we show that the PKA adaptor A-kinase interacting protein 1 (AKIP1) is up-regulated in cardiac myocytes in response to oxidant stress. Mice with cardiac gene transfer of AKIP1 have enhanced protection to ischemic stress. We hypothesized that this adaptation to stress was mitochondrial dependent. AKIP1 interacted with the mitochondrial localized apoptosis inducing factor (AIF) under both normal and oxidant stress. When cardiac myocytes or whole hearts are exposed to oxidant and ischemic stress, levels of both AKIP1 and AIF were enhanced. AKIP1 is preferentially localized to interfibrillary mitochondria and up-regulated in this cardiac mitochondrial subpopulation on ischemic injury. Mitochondria isolated from AKIP1 gene transferred hearts showed increased mitochondrial localization of AKIP1, decreased reactive oxygen species generation, enhanced calcium tolerance, decreased mitochondrial cytochrome C release,and enhance phosphorylation of mitochondrial PKA substrates on ischemic stress. These observations highlight AKIP1 as a critical molecular regulator and a therapeutic control point for stress adaptation in the heart.

Lipomatous variant of angiomyofibroblastoma: a case report and review of the literature.

Angiomyofibroblastoma represents a rare, benign mesenchymal tumor with a predilection for the vulvovaginal region. Lipomatous change may occur but rarely comprises a substantial component of the lesion. There are only eight reports in the English language literature describing the lipomatous variant of this tumor. We describe a further lipomatous angiomyofibroblastoma that occurred on the labium majus of a 49-year-old woman. The histopathologic and immunohistochemical features are described, and the collective experience in the literature is reviewed.

Sevoflurane administration initiated out of the ED for life-threatening status asthmaticus.

Status asthmaticus is both a common and dangerous cause of acute dyspnea in the emergency department (ED) setting. Although most cases respond favorably to standard treatment, there are rare cases in which therapy beyond traditional treatment is needed. One of these treatment modalities includes inhalational anesthesia. We present a case in which inhaled sevoflurane was initiated out of the ED for a life-threatening asthma exacerbation refractory to conventional treatment. To our knowledge, this is only the second case to report the use of inhaled anesthetics initiated out of the ED for status asthmaticus and is the first report of its kind to thoroughly detail the respiratory response noted while inhalation anesthesia was being implemented. A brief review of other case reports involving the use of sevoflurane for asthma is included. This case, as well as the others reviewed, illustrates the significant beneficial effect inhaled anesthetics can have on asthma, making this a treatment modality that must be recognized and appreciated by all emergency medicine providers.

Multiple reaction monitoring mass spectrometry for the discovery and quantification of O-GlcNAc-modified proteins.

O-linked N-acetylglucosamine (O-GlcNAc) is a post-translational modification regulating proteins involved in a variety of cellular processes and diseases. Unfortunately, O-GlcNAc remains challenging to detect and quantify by shotgun mass spectrometry (MS) where it is time-consuming and tedious. Here, we investigate the potential of Multiple Reaction Monitoring Mass Spectrometry (MRM-MS), a targeted MS method, to detect and quantify native O-GlcNAc modified peptides without extensive labeling and enrichment. We report the ability of MRM-MS to detect a standard O-GlcNAcylated peptide and show that the method is robust to quantify the amount of O-GlcNAcylated peptide with a method detection limit of 3 fmol. In addition, when diluted by 100-fold in a trypsin-digested whole cell lysate, the O-GlcNAcylated peptide remains detectable. Next, we apply this strategy to study glycogen synthase kinase-3 beta (GSK-3ß), a kinase able to compete with O-GlcNAc transferase and modify identical site on proteins. We demonstrate that GSK-3ß is itself modified by O-GlcNAc in human embryonic stem cells (hESC). Indeed, by only using gel electrophoresis to grossly enrich GSK-3ß from whole cell lysate, we discover by MRM-MS a novel O-GlcNAcylated GSK-3ß peptide, bearing 3 potential O-GlcNAcylation sites. We confirm our finding by quantifying the increase of O-GlcNAcylation, following hESC treatment with an O-GlcNAc hydrolase inhibitor. This novel O-GlcNAcylation could potentially be involved in an autoinhibition mechanism. To the best of our knowledge, this is the first report utilizing MRM-MS to detect native O-GlcNAc modified peptides. This could potentially facilitate rapid discovery and quantification of new O-GlcNAcylated peptides/proteins.