Browsing by Author "Kraus, VB"

Now showing 1 - 9 of 9
  • No Thumbnail Available
    ItemOpen Access
    Biomarkers of PTA
    (Post-Traumatic Arthritis: Pathogenesis, Diagnosis and Management, 2015-01-01) Golightly, YM; Adams, SB; Kraus, VB
    © Springer Science+Business Media New York 2015.Prognostic biomarkers may indicate the likelihood of disease development and speed of progression or may serve as predictive indicators of responsiveness to treatment. Joint injuries, particularly severe injuries, may result in post-traumatic osteoarthritis (PTOA), and pre- and post-injury prognostic biomarkers are needed to enhance primary and secondary prevention approaches for PTOA. Several macromolecules from joint structures found in serum, urine, and synovial fluid are promising biochemical markers for monitoring joint metabolism and health before and after joint injury. The use of metabolic profiling (analysis of small molecules) as a predictive tool for osteoarthritis (OA) has increased in the past decade. Although there is some question as to whether PTOA and idiopathic OA are comparable conditions, there is some evidence to suggest that components of their pathogenesis are similar. Potentially, biomarkers important to the high-risk PTOA profile translate to idiopathic OA. Further work is needed to confirm the utility of macromolecules and metabolites as biomarkers for PTOA, particularly focusing on those strongly correlated to clinical efficacy measures important to the patient (e.g., symptoms, physical function, and quality of life) and the causal pathway of PTOA.
  • Thumbnail Image
    ItemOpen Access
  • Thumbnail Image
    ItemOpen Access
    Monosodium urate crystal induced macrophage inflammation is attenuated by chondroitin sulphate: pre-clinical model for gout prophylaxis?
    (BMC Musculoskelet Disord, 2014-09-27) Orlowsky, EW; Stabler, TV; Montell, E; Vergés, J; Kraus, VB
    BACKGROUND: Chondroitin Sulphate (CS), a natural glycosaminoglycan of the extracellular matrix, has clinical benefit in symptomatic osteoarthritis but has never been tested in gout. In vitro, CS has anti-inflammatory and positive effects on osteoarthritic chondrocytes, synoviocytes and subchondral bone osteoblasts, but its effect on macrophages is unknown. The purpose of our study was to evaluate the in vitro effects of CS on monosodium urate (MSU)-stimulated cytokine production by macrophages. METHODS: THP-1 monocytes were differentiated into mature macrophages using a phorbol ester, pretreated for 4 hours with CS in a physiologically achievable range of concentrations (10-200 μg/ml) followed by MSU crystal stimulation for 24 hours. Cell culture media were analyzed by immunoassay for factors known to be upregulated during gouty inflammation including IL-1β, IL-8 and TNFα. The specificity of inflammasome activation by MSU crystals was tested with a caspase-1 inhibitor (0.01 μM-10 μM). RESULTS: MSU crystals ≥10 mg/dl increased macrophage production of IL-1β, IL-8 and TNFα a mean 7-, 3- and 4-fold respectively. Induction of IL-1β by MSU was fully inhibited by a caspase-1 inhibitor confirming inflammasome activation as the mechanism for generating this cytokine. In a dose-dependent manner, CS significantly inhibited IL-1β (p = 0.003), and TNFα (p = 0.02) production from macrophages in response to MSU. A similar trend was observed for IL-8 but was not statistically significant (p = 0.41). CONCLUSIONS: CS attenuated MSU crystal induced macrophage inflammation, suggesting a possible role for CS in gout prophylaxis.
  • Thumbnail Image
    ItemOpen Access
    Preclinical Osteoarthritis
    Kraus, VB
  • Thumbnail Image
    ItemOpen Access
    Radiographic severity of knee osteoarthritis is conditional on interleukin 1 receptor antagonist gene variations.
    (Ann Rheum Dis, 2010-05) Attur, M; Wang, HY; Kraus, VB; Bukowski, JF; Aziz, N; Krasnokutsky, S; Samuels, J; Greenberg, J; McDaniel, G; Abramson, SB; Kornman, KS
    BACKGROUND: A lack of biomarkers that identify patients at risk for severe osteoarthritis (OA) complicates development of disease-modifying OA drugs. OBJECTIVE: To determine whether inflammatory genetic markers could stratify patients with knee OA into high and low risk for destructive disease. METHODS: Genotype associations with knee OA severity were assessed in two Caucasian populations. Fifteen single nucleotide polymorphisms (SNPs) in six inflammatory genes were evaluated for association with radiographic severity and with synovial fluid mediators in a subset of the patients. RESULTS: Interleukin 1 receptor antagonist (IL1RN) SNPs (rs419598, rs315952 and rs9005) predicted Kellgren-Lawrence scores independently in each population. One IL1RN haplotype was associated with lower odds of radiographic severity (OR=0.15; 95% CI 0.065 to 0.349; p<0.0001), greater joint space width and lower synovial fluid cytokine levels. Carriage of the IL1RN haplotype influenced the age relationship with severity. CONCLUSION: IL1RN polymorphisms reproducibly contribute to disease severity in knee OA and may be useful biomarkers for patient selection in disease-modifying OA drug trials.
  • Thumbnail Image
    ItemOpen Access
    Rare Osteoarthritis: Ochronosis and Kashin-Beck Disease
    (Rheumatology, 6th edition, Ed. MC Hochberg, AJ Silman, JS Smolen, ME Weinblatt, MH Weisman (Mosby Elsevier, Philadelphia). 2014;Chapter 185:1536-1540.) Kraus, VB
  • Thumbnail Image
    ItemOpen Access
    Serum cholesterol levels within the high normal range are associated with better cognitive performance among Chinese elderly
    (Journal of Nutrition, Health and Aging, 2016-03-01) Lv, YB; Yin, ZX; Chei, CL; Brasher, MS; Zhang, J; Kraus, VB; Qian, F; Shi, X; Matchar, DB; Zeng, Y
    Objectives: The association between cognitive function and cholesterol levels is poorly understood and inconsistent results exist among the elderly. The purpose of this study is to investigate the association of cholesterol level with cognitive performance among Chinese elderly. Design: A cross-sectional study was implemented in 2012 and data were analyzed using generalized additive models, linear regression models and logistic regression models. Setting: Community-based setting in eight longevity areas in China. Subjects: A total of 2000 elderly aged 65 years and over (mean 85.8±12.0 years) participated in this study. Measurements: Total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) concentration were determined and cognitive impairment was defined as Mini-Mental State Examination (MMSE) score≤23. Results: There was a significant positive linear association between TC, TG, LDL-C, HDL-C and MMSE score in linear regression models. Each 1 mmol/L increase in TC, TG, LDL-C and HDL-C corresponded to a decreased risk of cognitive impairment in logistic regression models. Compared with the lowest tertile, the highest tertile of TC, LDL-C and HDL-C had a lower risk of cognitive impairment. The adjusted odds ratios and 95% CI were 0.73(0.62–0.84) for TC, 0.81(0.70–0.94) for LDL-C and 0.81(0.70–0.94) for HDL-C. There was no gender difference in the protective effects of high TC and LDL-C levels on cognitive impairment. However, for high HDL-C levels the effect was only observed in women. High TC, LDL-C and HDL-C levels were associated with lower risk of cognitive impairment in the oldest old (aged 80 and older), but not in the younger elderly (aged 65 to 79 years). Conclusions: These findings suggest that cholesterol levels within the high normal range are associated with better cognitive performance in Chinese elderly, specifically in the oldest old. With further validation, low cholesterol may serve a clinical indicator of risk for cognitive impairment in the elderly.
  • No Thumbnail Available
    ItemOpen Access
    Serum cholesterol levels within the high normal range are associated with better cognitive performance among Chinese elderly
    (Journal of Nutrition, Health and Aging, 2016-03-01) Lv, Y-B; Yin, ZX; Chei, C-L; Brasher, MS; Zhang, J; Kraus, VB; Qian, F; Shi, X-M; Matchar, DB; Zeng, Y
    © 2016, Serdi and Springer-Verlag France.Objectives: The association between cognitive function and cholesterol levels is poorly understood and inconsistent results exist among the elderly. The purpose of this study is to investigate the association of cholesterol level with cognitive performance among Chinese elderly. Design: A cross-sectional study was implemented in 2012 and data were analyzed using generalized additive models, linear regression models and logistic regression models. Setting: Community-based setting in eight longevity areas in China. Subjects: A total of 2000 elderly aged 65 years and over (mean 85.8±12.0 years) participated in this study. Measurements: Total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) concentration were determined and cognitive impairment was defined as Mini-Mental State Examination (MMSE) score≤23. Results: There was a significant positive linear association between TC, TG, LDL-C, HDL-C and MMSE score in linear regression models. Each 1 mmol/L increase in TC, TG, LDL-C and HDL-C corresponded to a decreased risk of cognitive impairment in logistic regression models. Compared with the lowest tertile, the highest tertile of TC, LDL-C and HDL-C had a lower risk of cognitive impairment. The adjusted odds ratios and 95% CI were 0.73(0.62–0.84) for TC, 0.81(0.70–0.94) for LDL-C and 0.81(0.70–0.94) for HDL-C. There was no gender difference in the protective effects of high TC and LDL-C levels on cognitive impairment. However, for high HDL-C levels the effect was only observed in women. High TC, LDL-C and HDL-C levels were associated with lower risk of cognitive impairment in the oldest old (aged 80 and older), but not in the younger elderly (aged 65 to 79 years). Conclusions: These findings suggest that cholesterol levels within the high normal range are associated with better cognitive performance in Chinese elderly, specifically in the oldest old. With further validation, low cholesterol may serve a clinical indicator of risk for cognitive impairment in the elderly.
  • Thumbnail Image
    ItemOpen Access
    Towards prevention of post-traumatic osteoarthritis: report from an international expert working group on considerations for the design and conduct of interventional studies following acute knee injury.
    (Osteoarthritis and cartilage, 2019-01) Watt, FE; Corp, N; Kingsbury, SR; Frobell, R; Englund, M; Felson, DT; Levesque, M; Majumdar, S; Wilson, C; Beard, DJ; Lohmander, LS; Kraus, VB; Roemer, F; Conaghan, PG; Mason, DJ; Arthritis Research UK Osteoarthritis and Crystal Disease Clinical Study Group Expert Working Group
    OBJECTIVE:There are few guidelines for clinical trials of interventions for prevention of post-traumatic osteoarthritis (PTOA), reflecting challenges in this area. An international multi-disciplinary expert group including patients was convened to generate points to consider for the design and conduct of interventional studies following acute knee injury. DESIGN:An evidence review on acute knee injury interventional studies to prevent PTOA was presented to the group, alongside overviews of challenges in this area, including potential targets, biomarkers and imaging. Working groups considered pre-identified key areas: eligibility criteria and outcomes, biomarkers, injury definition and intervention timing including multi-modality interventions. Consensus agreement within the group on points to consider was generated and is reported here after iterative review by all contributors. RESULTS:The evidence review identified 37 studies. Study duration and outcomes varied widely and 70% examined surgical interventions. Considerations were grouped into three areas: justification of inclusion criteria including the classification of injury and participant age (as people over 35 may have pre-existing OA); careful consideration in the selection and timing of outcomes or biomarkers; definition of the intervention(s)/comparator(s) and the appropriate time-window for intervention (considerations may be particular to intervention type). Areas for further research included demonstrating the utility of patient-reported outcomes, biomarkers and imaging outcomes from ancillary/cohort studies in this area, and development of surrogate clinical trial endpoints that shorten the duration of clinical trials and are acceptable to regulatory agencies. CONCLUSIONS:These considerations represent the first international consensus on the conduct of interventional studies following acute knee joint trauma.