GNPS - cyclic peptide 94NPD2 - positive mode
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Q Exactive
ORGANISM(S): Not Applicable
SUBMITTER: 
Marcy Balunas
PROVIDER: MSV000084312 | GNPS |
REPOSITORIES: GNPS
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Project description:This data set was collected on a qexactive coupled to a Thermo vanquish. Data was collected in a DDA fashion in negative mode. The project itself revolved around compound 94NPD2, a compound that is similar to veraguamides
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Project description:OBJECTIVE:To investigate the risk of progression to rheumatoid arthritis (RA) in patients who were cyclic citrullinated peptide (CCP) antibody positive without RA at initial presentation. METHODS:We performed a retrospective cohort study of CCP+ individuals seen at a US tertiary care system between 2009 and 2018 who were without RA or other systemic rheumatic disease by medical record review at the time of CCP antibody positivity. Progression to classifiable RA was determined through medical record review. We investigated the risk of progression to RA overall and stratified by CCP antibody level (low: >1 to 2× the upper limit of normal [ULN]; medium: >2 to 3× ULN; high: >3× ULN). Multivariable Cox regression estimated the hazard ratio (HR) and 95% confidence interval (95% CI) for RA by CCP antibody level. RESULTS:We identified 340 CCP+ patients who were without RA or other rheumatic disease at baseline. During 1,047 person-years of follow-up, 73 patients (21.5%) developed RA. The risk of progression to RA increased with CCP antibody level, with 46.0% (95% CI 34.7-55.3) of patients with high-level CCP antibodies progressing to RA by 5 years. Compared to low CCP antibody level, medium (HR 3.00 [95% CI 1.32-6.81]) and high (HR 4.83 [95% CI 2.51-9.31]) CCP antibody levels were strongly associated with progression to RA, adjusting for age, sex, body mass index, smoking, family history of RA, and rheumatoid factor level. CONCLUSION:Among CCP+ patients without RA, the risk for progression to RA increased substantially with increasing CCP antibody level. This study provides further support for close monitoring for development of RA among CCP+ patients and identifying strategies to mitigate this risk.
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Project description:The co-occurrence of autoimmune diseases such as rheumatoid arthritis (RA) and type 1 diabetes mellitus (DM) has been reported in individuals and families. In this study, the strength and nature of this association were investigated at the population level in a Swedish case-control cohort.For this case-control study, 1,419 patients with incident RA diagnosed between 1996 and 2003 were recruited from university, public, and private rheumatology units throughout Sweden; 1,674 matched control subjects were recruited from the Swedish national population registry. Sera from the subjects were tested for the presence of antibodies to cyclic citrullinated peptide (anti-CCP), rheumatoid factor (RF), and the 620W PTPN22 allele. Information on a history of diabetes was obtained by questionnaire, telephone interview, and/or medical record review. The prevalence of type 1 DM and type 2 DM was compared between patients with incident RA and control subjects and further stratified for the presence of anti-CCP, RF, and the PTPN22 risk allele.Type 1 DM was associated with an increased risk of RA (odds ratio [OR] 4.9, 95% confidence interval [95% CI] 1.8-13.1), and this association was specific for anti-CCP-positive RA (OR 7.3, 95% CI 2.7-20.0), but not anti-CCP-negative RA. Further adjustment for the presence of PTPN22 attenuated the risk of anti-CCP-positive RA in patients with type 1 DM to an OR of 5.3 (95% CI 1.5-18.7). No association between RA and type 2 DM was observed.The association between type 1 DM and RA is specific for a particular RA subset, anti-CCP-positive RA. The risk of developing RA later in life in patients with type 1 DM may be attributed, in part, to the presence of the 620W PTPN22 allele, suggesting that this risk factor may represent a common pathway for the pathogenesis of these 2 diseases.
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