Alkylresorcinol, a biomarker for whole grain intake, and its association with osteoarthritis: the MOST study

INTRODUCTION

Higher intake of fiber has been associated with lower risk of incident symptomatic osteoarthritis (OA). We examined whether levels of alkylresorcinol (AR), a marker of whole grain intake, were associated with OA in subjects in The Multicenter Osteoarthritis (MOST) Study.

METHOD

Knee x-rays and knee pain were assessed at baseline and through 60-months. Stored baseline fasting plasma samples were analyzed for AR homologues (C17:0, C19:0, C21:0, C23:0, C25:0) and total AR levels (AR sum). Two nested case-control studies, one for incident radiographic OA and one for incident symptomatic OA were performed with participants re-assessed at 15, 30 and 60 months. Multivariable conditional logistic regression with baseline covariates including age, sex, BMI, physical activity, quadriceps strength, race, smoking, depressive symptoms, diabetes and knee injury tested the association of log transformed AR levels with OA outcomes.

RESULTS

Seven hundred seventy-seven subjects were, on average, in their 60's, and most were women. For 60-month cumulative incidence, there was no significant association between quartiles of AR concentration and incident radiographic (e.g., for incident radiographic OA, highest vs lowest quartile of AR sum showed RR = 0.93 (95% CI 0.59, 1.47), and for symptomatic OA RR was 1.22 (95% CI 0.76, 1.94). In secondary analyses examining 30-month incidence, high AR levels were associated with a reduced risk of X-ray OA (RR = 0.31 (95% CI 0.15, 0.64).

CONCLUSION

In primary analyses, AR levels were not associated with risk of OA, but secondary analyses left open the possibility that high AR levels may protect against OA.

Anti-enteric efficacy and mode of action of tridecanoic acid methyl ester isolated from Monochoria hastata (L.) Solms leaf

Monochoria hastata (L.) Solms (family Pontederiaceae), an ethnomedicinal aquatic herb, is used to remedy several gastrointestinal diseases by various ethnic groups in India. The present study aimed to purify and characterize the antibacterial active ingredient against gastrointestinal (GI) diseases and its mode of action using in vitro experimental models. The active lead molecule in the ethyl acetate extract (EA-Mh) fraction has been purified and characterized through high-performance liquid chromatography (HPLC), proton nuclear magnetic resonance (1H NMR), and electrospray ionization mass spectrometry (ESI-MS) methods. The anti-enteric efficacy has been evaluated against enteropathogenic Gram-positive and Gram-negative bacteria by minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), lactate dehydrogenase (LDH), and scanning electron microscopy (SEM) studies. The synergistic and antagonistic studies were done on E. coli MTCC 723 using standard antibiotics (ampicillin and kanamycin, final conc. 50 µg/ml) in a sterilized 96-well micro-plate, incubated at 37 ℃ for 24 h. The chromatographic and spectroscopic analyses revealed the presence of tridecanoic acid methyl ester (TAME) in the bioactive fraction. The compound causes significant extracellular leakage activity by disrupting cellular morphology in the Enterococcus faecalis MCC 2041 T and Salmonella enterica serovar Typhimurium MTCC 98, at a dose of 375 μg/ml and 750 μg/ml, respectively. The SEM study shows a significant rupturing of E. coli and E. faecalis cells due to TAME induced autolysis. It has synergistic activity with ampicillin. The in silico molecular docking through the AutoDock Vina 4.2 and GROMACS (ver. 5.1) Charmm27 force field results showed that the TAME had a strong binding affinity Escherichia coli DNA Gyrase B (PDB ID: 5l3j.pdb) protein and caused conformational changes. Thus, the manuscript reports the first time on the characterization of TAME from this plant with a detailed antibacterial mode of action studies.

Inhibitory efficacy of RNA virus drugs against SARS-CoV-2 proteins: An extensive study

Herein we have made a comprehensive analysis of inhibitory efficacy of 16 RNA virus drugs against RdRp, Mpro and PLpro proteins of SARS-CoV-2. Analysis of docked conformation revealed that Baloxavir marboxil (BMX) corresponds to the highest binding energy. Analysis of residue confirmed that BMX strongly interact with these three proteins involving H-bonding, ionic as well as hydrophobic interactions. Molecular dynamics simulation and analysis of parameters like RMSD, RMSF, binding energy confirmed noticeable conformational alternation with these proteins with makeable effect on RdRp. The potentially inhibitory action of BMX against these three proteins suggests the inhibition of overall transcription process of SARS-CoV-2. These observation along with the recently observed inhibitory action of BMX on influenza with clinically proven no side effects emphasizes to uncover the role of BMX by in-vitro and in-vivo analysis.

AB0581 HIGH PREVALENCE OF TUBERCULOSIS IN ADULTS AND CHILDREN WITH IIM AS COMPARED WITH SLE: RETROSPECTIVE DATA REVIEW FROM A LARGE COHORT AT A TERTIARY CARE CENTER IN INDIA

Background:

Infections are the most common cause of morbidity and mortality in idiopathic inflammatory myositis (IIM). India is endemic for Tuberculosis (TB) with a prevalence of 2.3 cases per thousand population.

Objectives:

Thus, we studied the prevalence of TB in our cohort of IIM patients and compared with that in systemic lupus erythematosus (SLE).

Methods:

Medical records from paper charts and electronic medical records were reviewed for adults and juvenile patients with SLE (ACR criteria 1997) and IIM (Bohan and Peter criteria 1975) first presented at a tertiary care hospital in India from 1989 to 2016. Clinical variables including disease characteristics variables, the frequency, site, duration and complication of active TB as well as dose of corticosteroids and other immunosuppressive drugs were extracted retrospectively from the medical records. Descriptive statistics were used to describe the cohort and TB characteristics. Chi-square and t-test were used to evaluate association of TB with clinical diagnosis as well as medication data.

Results:

There were 167 (132 adults and 35 juvenile) IIM and 280 (131 adults and 149 juvenile) SLE in our cohort. Active TB occurred in 24 (14.4%) of all IIM cases (18, 13.6% adults; 6, 17.1% juvenile) as compared to 18 (6.4%) of all SLE cases (8, 6.1% adults; 10, 6.7% juvenile, p value < 0.01). Of all the TB in myositis, most often it was seen in Dermatomyositis (n=11, 45.8%) followed by Polymyositis (5, 20.8%), and occasionally in Overlap myositis (3, 12.5) and juvenile dermatomyositis (1,4.1%).

Considering an annual TB rate of 211 per 100,000 of the general population, the risk of developing active TB was 62-fold higher in patients with IIM and 27-fold higher in those with lupus. Patients with IIM had higher odds of developing TB as compared with Lupus [odds ratio 2.86 (CI 1.5-5.47), p=0.007).

Amongst 24 IIM patients with TB, 10 had pulmonary TB and 14 had extra-pulmonary TB. The median glucocorticoid dose at the diagnosis of TB was 0.25 (0-1.5) mg/kg/day. Half the cases of active TB occurred during inactive myositis. Seventeen patients with active TB were followed up over 27 months (8-184), with remission of TB in all cases but required prolonged courses of Anti-Tuberculous Therapy (ATT) in 25% cases with 10 ATT related adverse events in 8 patients and 5 patients with relapse of myositis due to lowering of immunosuppression.

Conclusion:

Patients with IIM have higher prevalence of active TB as compared with SLE patients. The risk is highest in patients with Dermatomyositis possibly related to high doses of steroids. Extra-pulmonary forms of TB are more common, and patients commonly require prolonged course of ATT and may suffer relapses of myositis during ATT. Screening for latent TB may be useful in IIM patients before prescribing steroids and other immunosuppressive drugs.

References:

[1]TB Statistics India | National, treatment outcome & state statistics [Internet]. TB Facts | TB, tests, drugs, statistics. [cited 2019 Jun 13]. Available from:https://www.tbfacts.org/tb-statistics-india/

[2]Muhammed H, Gupta L, Zanwar A, Misra DP, Lawrence A, Agarwal V, Aggarwal A, Misra R;OPC0243: Infections are leading cause of in-hospital mortality in patients with inflammatory myositis; Indian J Rheumatol 2018;13, Suppl S2:93-241

[3]Gaitonde S, Pathan E, Sule A, Mittal G, Joshi VR. Efficacy of isoniazid prophylaxis in patients with systemic lupus erythematosus receiving long term steroid treatment. Ann Rheum Dis. 2002 Mar;61(3):251–3.

[18]He D, Bai F, Zhang S, Jiang T, Shen J, Zhu Q, et al. High incidence of tuberculosis infection in rheumatic diseases and impact for chemoprophylactic prevention of tuberculosis activation during biologics therapy. Clin Vaccine Immunol CVI. 2013 Jun;20(6):842–7.

Figure 1.

(A) Prevalence and (B) sites of tuberculosis

Table 1.

Table 2.

Clinical profile of patients with Tuberculosis

Disclosure of Interests:

Latika Gupta: None declared, Abhishek Zanwar: None declared, Rohit Aggarwal Grant/research support from: Pfizer, Genentech, BMS, Mallinckrodt, Consultant of: Pfizer, Genentech, BMS, Mallinckrodt, Bristol Myers-Squibb, octapharma, CSL Behring, AstraZeneca, Corbus, Kezar, Abbvie, Able Lawrence: None declared, Durga Misra: None declared, Vikas Agarwal: None declared, Ramnath Misra: None declared, Amita Aggarwal: None declared

SAT0319 SUBCLINICAL ATHEROSCLEROSIS IN INDIAN PATIENTS WITH SCLERODERMA – CLINICAL AND SEROLOGICAL ASSOCIATIONS

Background:

Scleroderma has been associated with increased risk of cardiovascular events, however,studies on this from India are sparse.We evaluated clinical and serological factors associated with subclinical atherosclerosis in Indian patients with scleroderma, in a cross-sectional design.

Objectives:

To compare carotid intima-medial thickness (CIMT, mean value of both carotids) as a measure of subclinical atherosclerosis (SCA) between patients with scleroderma (n=61) fulfilling 2013 ACR/EULAR criteria, and healthy controls (n=41).

- To compare clinical (body mass index – BMI, waist-hip ratio – WHR, fasting lipid profile) and serological factors (microparticles, endothelial microparticles, inflammatory cytokines associated with increased cardiovascular risk) between patients with scleroderma and healthy controls.

- To identify factors associated with SCA in scleroderma patients.

Methods:

Subclinical atherosclerosis(SCA) was defined by presence of carotid plaques, or increased CIMT >2 standard deviations compared with Indian reference standards for age and sex. Total microparticles (TMP) were measured of plasma after ultracentrifugation as per previously described protocol using microbeads of 3 μm size (TMP were of size 0.1-1 μm); of these, microparticles positive for CD31 and CD142 were endothelial microparticles (EMP). Serum cytokines (IL-1, IL-6, TNF-α, IL-17) were measured by ELISA using manufacturer instructions. Linear regression was used to identify the determinants of CIMT in scleroderma. Binomial logistic regression was used to identify factors associated with subclinical athersclerosis in scleroderma.

VariablePatients with scleroderma (n=61)Healthy controls (n=41)p valueAge37.8 ± 11.9235.37 ± 6.690.2375Gender (M:F)11:506:350.6516Diabetes/Hypertension/Tobacco use1/2/00/0/0NSBody mass index (kg/m2)20.11 ± 3.8224.38 ± 4.45<0.0001Waist-hip ratio0.86 ± 0.110.89 ± 0.070.1251Total cholesterol (mg/dL)142.5 ± 30.7147.3 ± 39.50.4948Triglycerides (mg/dL)99.4 ± 37121.4 ± 460.0087HDL cholesterol (mg/dL)46.9 ± 4.946.1 ± 4.20.4029LDL cholesterol (mg/dL)93.6 ± 10.593.3 ± 7.50.8520VLDL cholesterol (mg/dL)19.9 ± 7.424.7 ± 9.70.0057Carotid intima-medial thickness (mm)0.68 ± 0.100.53 ± 0.03<0.0001Total microparticles (per±L)12913 ± 24936272 ± 1533<0.0001Endothelial microparticles (per±L)2623 ± 1032829 ± 439.5<0.0001Serum IL-1±(pg/mL)38.19 ± 13.4631.38 ± 18.290.0326IL-6 (pg/mL)176.6 ± 85.74128.9 ± 53.610.0020IL-17 (pg/mL)56.3 ± 20.4553.89 ± 20.510.5611TNF±(pg/mL)49.65 ± 26.7142.09 ± 30.410.1879

Results:

Despite lower BMI, triglycerides and VLDL cholesterol, CIMT was significantly higher in patients with scleroderma. Patients with scleroderma had significantly higher total microparticles and endothelial microparticles in plasma, and serum IL-1± and IL-6 (Table 1). On multivariable regression, age was the only significant determinant of CIMT. 28 (45.9%) patients had SCA; 13 (21.3%) had carotid plaques. Patients with SCA had higher proportion of males (9/28 in those with SCA vs 2/33 in those without SCA). Binomial logistic regression did not identify any other significant predictors of SCA.

Table 1

Comparison between patients with scleroderma and healthy controls

Serum IL-1± (pg/mL)38.19 ± 13.4631.38 ± 18.290.0326IL-6 (pg/mL)176.6 ± 85.74128.9 ± 53.610.0020IL-17 (pg/mL)56.3 ± 20.4553.89 ± 20.510.5611TNF± (pg/mL)49.65 ± 26.7142.09 ± 30.410.1879

Conclusion:

Patients with scleroderma had significant burden of subclinical atherosclerosis, which could not be explained by traditional or novel cardiovascular risk factors.

References:

[1]Psarras A, Soulaidopoulos S, Garyfallos A, Kitas G, Dimitroulas T. A critical view on cardiovascular risk in systemic sclerosis. Rheumatol Int. 2017 Jan; 37(1):85-95.

[2]Jung C, Drummer K, Oelzner P, Figulla HR, Boettcher J, Franz M, et al. The association between endothelial microparticles and inflammation in patients with systemic sclerosis and Raynaud’s phenomenon as detected by functional imaging. Clin HemorheolMicrocirc. 2015; 61(3):549-557.

Acknowledgments:

Supported by IRA(Indian Rheumatology Association) Research Grant to DP Misra.

Disclosure of Interests:

None declared

AB0149 PERIPHERAL T HELPER SUBSET PROFILING DIFFERS IN VARIOUS SUBSETS OF IDIOPATHIC INFLAMMATORY MYOSITIS

Background:

There is dearth of biomarkers in Idiopathic Inflammatory Myositis(IIM) to identify ongoing inflammation in the muscle and distinguish it from inactivity or damage.

Objectives:

Since myositis is autoantibody mediated and tertiary lymphoid organogenesis (TLO) reported in the diseased muscles, we investigated peripheral blood T helper subset profiling as a reflection of ongoing muscle inflammation.

Methods:

Twenty-six patients of IIM (ACR EULAR criteria) were compared with 15 healthy controls (HC) and 21 patients with sarcoidosis (Table 1). Peripheral blood mononuclear cells were stained with combinations of antibodies to identify Th1, Th17, Th17.1 and Treg cells after stimulation assays (BD Biosciences). Myositis Specific and Associated autoantibodies were tested by the line immunoassay (Euroimmune, Germany).

Table 1.

Baseline characteristics of patients with inflammatory myositis

CharacteristicsDemographic details (n, % or median, IQR)Healthy Control (median, IQR)Age37±25.2526.0±32Gender(M:F)5 vs. 2112 vs. 3Diagnosis PM3 DM15 OM4 ASS4Disease course Monocyclic5 Polycyclic7 Chronic continuous1 Undefined13Clinical Profile Myositis4 (15.3%) ILD5 (19.23%) Rash3 (11.53%) Arthritis6 (23.07%) Other16 (23.69)Disease duration (years)1.3 ± 6.91Disease activity Active12 [PM(1), OM(1), ASS(4), DM(5)] Inactive14 [PM(2),OM(2),ASS(0),DM(8)]Antinuclear AntibodiesPositive Nuclear  Speckled9 (34.61%)  Homogenous4 (15.38%)  Nucleolar1 (3.8%) Other5 (19.23%)Cytoplasmic3 (11.53%)Negative4 (15.38%)Myositis Specific AntibodiesPositive ARS2(7.6%) Mi-23(11.53%) SAE-12(7.6%) NXP22(7.6%) MDA50MAA Ku1(3.8%) dsDNA0 U1RNP0 Ro524(15.38%)Negative12(46.15%)

Results:

All T helper subsets were higher in myositis as compared with healthy controls (figure 1A a-d). Between various IIM subsets, polymyositis had higher Th1 and Treg cells (Figure 1B b, c) while Th17 and Th17.1 cells(c) were higher in Overlap Myositis (Figure 1B a, d) as compared with healthy controls. Patients with sarcoidosis had similar subset profiling as myositis.(Figure 5a-f)

Figure 1

A. Representative plot depicting all T helper subsets quantified were higher in myositis as compared with healthy controls1B: Representative plot comparing %T cell subsets in various subsets of myositis with healthy controls showing that % Th1 cells (a) and Tregs (d) are highest in Polymyositis than controls while % Th17 (b) and % Th17.1 cells (c) are higher in Overlap Myositis

Patients who were had either arthritis or were positive for myositis specific autoantibodies had higher Th17.1 cells (Figure 3 a(iii) & b(iii)) than those negative for MSA. There was no difference in T cell profile between the various autoantibody subsets (Figure 6a-d).

There was no difference in subsets between active and inactive disease although active disease had lower Th1/Treg, Th17/Treg and Th17.1/Treg ratios.

Conclusion:

T Helper cell subsets are distinct from HC but similar to sarcoidosis patients. However, they differ in various subsets of myositis, suggesting different pathogenic mechanisms are operative. Autoantibody positivity is associated with elevated Th17.1 population suggesting plasticity in TLO which needs to be explored further. However, T cell profiling cannot distinguish active from inactive disease limited predictive potential as a biomarker.

Figure 2

Acknowledgments:

The authors thank APLAR for funding Myositis antibody testing.

Disclosure of Interests:

None declared

SAT0230 MACROPHAGE ACTIVATION SYNDROME IN SLE AND SYSTEMIC ONSET JIA: SIMILAR OR DISSIMILAR

Background:

Macrophage activation syndrome (MAS) is a serious complication in rheumatic disease. Fever and hyperferritinemia are common in systemic onset JIA and cytopenias are common in SLE thus recognising MAS in them is a challenge.

Objectives:

We compared clinical, laboratory parameters, various classification criteria for MAS, and its outcome in SLE and sJIA.

Methods:

Clinical and laboratory data were extracted from clinician diagnosed cases of MAS with SLE/sJIA who were admitted between 2004-2018 at a tertiary care hospital. Percentage of patients satisfying Ravelli, International consensus, HLH 2004 and criteria proposed by Parodi et al1were calculated.

Results:

Among 33 patients (18 females) with MAS 19 had SLE and 14 had sJIA. MAS was more likely to be the presenting manifestation of disease in SLE as compared to sJIA (p<0.05). There were no differences in the clinical features among these two diseases. EBV and CMV were identified in 2 patients each as the trigger for MAS.

Patients with SLE had lower baseline TLC and platelet whereas patients with sJIA-MAS had significantly higher median CRP (p = 0.002), fall in TLC (p=0.012) and delta ESR/CRP ratio (p=0.02) and lower fibrinogen level (p=0.006). Neutrophil to lymphocyte ratio, Ferritin/CRP ratio and number of patients with Ferritin/ESR >80 were similar. Bone Marrow hemophagocytosis was seen in only in 21% of patients.

Only 6/33 fulfilled HLH criteria but criteria meant for sJIA or SLE performed well for both diseases and majority of patients could be diagnosed using them. Treatment included steroids(100%), cyclosporine(30%), Tacrolimus(21%), cyclophosphamide(21%), etoposide(3%) and thalidomide(12%). Mortality was similar in both groups.

Table 1.

Agreement amongst MAS/HLH criteria in SLE and sJIA MAS

SLE-MASHLHRavelli et alConsensusParodi et alHLH4444Ravelli et al4191918Consensus4191918Parodi et al4181818sJIA-MASHLHRavelli et alConsensusParodi et alHLH2222Ravelli et al2121112Consensus2111212Parodi et al2121214Table 2.

Comparison with various other cohorts

Minoia et alsJIAn (%)Our studysJIA, n (%)Our Study SLE, n (%)SLE, n (%) Ai-Chun Liu et alJuvenile SLE n (%)Parodi et alNumber36214193238MAS as presenting feature (%)80 (22)4 (28)12 (63)NA24 (63)Most common manifestation (%)Fever (96)Fever (100)Fever (89)Fever (96)Fever (89)Most common triggerDisease activityDisease activityDisease activityDisease activityDisease activityBM done251 (72.3)8 (57)12 (63)32 (96)38 (100)BM hemophagocytosis150 (60.7)2 (25)5 (41)32 (100)20 (52)Mortality28 (8)2 (14)2 (10.5)4 (12.5)4 (11.4)Patients meeting JIA criteria %NA-100NA100Patients meeting HLH criteria %NA1419NA66

Conclusion:

MAS is more likely to be presenting manifestation in SLE compared to sJIA. Though lab parameters are significantly different in MAS associated with SLE & sJIA, criteria meant for MAS in sJIA or SLE MAS performed equally well in both diseases.

References:

[1]Parodi A et al, Macrophage activation syndrome in juvenile systemic lupus erythematosus: a multinational multicenter study of thirty-eight patients. Arthritis Rheum. 2009 Nov;60(11):3388-99.

Disclosure of Interests:

None declared

Thiazide diuretics and risk of knee replacement surgery among patients with knee osteoarthritis: a general population-based cohort study

OBJECTIVE

Thiazide diuretic use is associated with higher bone mineral density (BMD) and possibly lower serum magnesium levels than loop diuretic use, and both high BMD and low serum magnesium have been linked to high prevalent knee osteoarthritis. This study aimed to compare the risk of a clinically relevant endpoint, knee replacement (KR) surgery, among initiators of thiazide and loop diuretics.

DESIGN

Among patients aged ≥50 years with a diagnosis of knee osteoarthritis in The Health Improvement Network (THIN) in United Kingdom, we conducted a propensity score-matched cohort study to examine the relation of thiazide diuretic initiation vs loop diuretic initiation to the risk of KR over 5 years.

RESULTS

Among thiazide and loop diuretic initiators (n = 3,488 for each group; mean age: 73 years; female ratio: 59%), 359 (28.6/1,000 person-years) and 283 (24.1/1,000 person-years) KRs occurred during the follow-up period, respectively. The hazard ratio (HR) of KR for thiazide diuretic initiation vs loop diuretic initiation was 1.26 (95% confidence interval [CI]: 1.08-1.47). The adherence-adjusted HR of KR for continuous use of thiazide diuretics was 1.44 (95% CI: 1.21-1.72).

CONCLUSIONS

In this population-based cohort of patients with knee osteoarthritis, thiazide diuretic use was associated with a higher risk of KR than loop diuretic use. This association may potentially be due to thiazide diuretics' effect on BMD and serum magnesium.

Relationships between misreported energy intake and pregnancy in the pregnancy, infection and nutrition study: new insights from a dynamic energy balance model

OBJECTIVE

Providing effective dietary counselling so that pregnancy weight gain remains within the 2009 Institute of Medicine (IOM) guidelines requires accurate maternal energy intake measures. Current practice is based on self-reported intake that has been demonstrated unreliable. This study applies an objective calculation of energy intake from a validated mathematical model to identify characteristics of individuals more likely to misreport during pregnancy.

METHODS

A validated maternal energy balance equation was used to calculate energy intake from gestational weight gain in 1,368 subjects. The difference between self-reported and model-predicted energy intake was tested for demographics, economic status, education level and maternal health status.

RESULTS

A weight gain of 15.2 kg resulted in model-predicted intake during pregnancy of 2,882.97 ±  135.71 kcal day-1, which differed from self-reported intake of 2,180.5 ± 856.0 kcal day-1. The achieved weight gain exceeded the IOM guidelines; however, the model predicted weight gain from self-reported energy intake was below IOM guidelines. Higher income (p = 0.004), education (p = 0.003), birth weight (p = 0.017), gestational diabetes (p = 0.008) and pre-existing diabetes (p < 0.001) were associated with under-reported energy intake. More children living at home (p = 0.001) were associated with more accurate self-reported intake.

CONCLUSIONS

When assessing self-reported energy intake in pregnancy studies, birth weight, gestational diabetes status, pre-existing diabetes, higher income and education predict higher under-reporting. Clinicians providing dietary treatment recommendations during pregnancy should be aware that individuals with pre-existing diabetes and gestational diabetes mellitus are more likely to misreport their intake. Additionally, the systems model approach can be applied early in intervention to objectively monitor dietary compliance to treatment recommendations.

Electron and recoil ion momentum imaging with a magneto-optically trapped target

A reaction microscope (ReMi) has been combined with a magneto-optical trap (MOT) for the kinematically complete investigation of atomic break-up processes. With the novel MOTReMi apparatus, the momentum vectors of the fragments of laser-cooled and state-prepared lithium atoms are measured in coincidence and over the full solid angle. The first successful implementation of a MOTReMi could be realized due to an optimized design of the present setup, a nonstandard operation of the MOT, and by employing a switching cycle with alternating measuring and trapping periods. The very low target temperature in the MOT (∼2 mK) allows for an excellent momentum resolution. Optical preparation of the target atoms in the excited Li 2(2)P3/2 state was demonstrated providing an atomic polarization of close to 100%. While first experimental results were reported earlier, in this work, we focus on the technical description of the setup and its performance in commissioning experiments involving target ionization in 266 nm laser pulses and in collisions with projectile ions.

CT imaging for evaluation of calcium crystal deposition in the knee: initial experience from the Multicenter Osteoarthritis (MOST) study

OBJECTIVE

Role of intra-articular calcium crystals in osteoarthritis (OA) is unclear. Imaging modalities used to date for its evaluation have limitations in their ability to fully characterize intra-articular crystal deposition. Since Computed Tomography (CT) imaging provides excellent visualization of bones and calcified tissue, in this pilot project we evaluated the utility of CT scan in describing intra-articular calcium crystal deposition in the knees.

METHOD

We included 12 subjects with and four subjects without radiographic chondrocalcinosis in the most recent visit from the Multicenter Osteoarthritis (MOST) study, which is a longitudinal cohort of community-dwelling older adults with or at risk for knee OA. All subjects underwent CT scans of bilateral knees. Each knee was divided into 25 subregions and each subregion was read for presence of calcium crystals by a musculoskeletal radiologist. To assess reliability, readings were repeated 4 weeks later.

RESULTS

CT images permitted visualization of 25 subregions with calcification within and around the tibio-femoral and patello-femoral joints in all 24 knees with radiographic chondrocalcinosis. Intra-articular calcification was seen universally including meniscal cartilage (most common site involved in 21/24 knees), hyaline cartilage, cruciate ligaments, medial collateral ligament and joint capsule. Readings showed good agreement for specific tissues involved with calcium deposition (kappa: 0.70, 95% CI 0.62-0.80).

CONCLUSION

We found CT scan to be a useful and reliable tool for describing calcium crystal deposition in the knee and therefore potentially for studying role of calcium crystals in OA. We also confirmed that "chondrocalcinosis" is a misnomer because calcification is present ubiquitously.

Incident long-term warfarin use and risk of osteoporotic fractures: propensity-score matched cohort of elders with new onset atrial fibrillation

Association between warfarin use and fracture risk is unclear. We examined the association between long-term warfarin use and fracture risk at the hip, spine, and wrist in elders. No significant association was found between long-term warfarin use and fracture risk, despite biological plausibility.

INTRODUCTION

Prior studies examining the association of warfarin use and osteoporotic fractures have been conflicting, potentially related to methodological limitations. Thus, we examined the association of long-term warfarin use with risk of hip, spine, and wrist fractures among older adults with atrial fibrillation, attempting to address prior methodologic challenges.

METHODS

We included men and women ≥ 65 years of age with incident atrial fibrillation and without prior history of fractures from The Health Improvement Network followed between 2000 and 2010. Long-term warfarin use was defined in two ways: (1) warfarin use ≥ 1 year; (2) warfarin use ≥ 3 years. Propensity-score matched cohorts of warfarin users and nonusers were created to evaluate the association between long-term warfarin use and risk of hip, spine, and wrist fractures separately as well as combined, using Cox-proportional hazards regression models.

RESULTS

Among >20,000 participants with incident atrial fibrillation, the hazard ratios (HR) for hip fracture with warfarin use ≥ 1 and ≥ 3 years, respectively, were 1.08 (95%CI 0.87, 1.35) and 1.13 (95% CI 0.84, 1.50). Similarly, no significant associations were observed between long-term warfarin use and risk of spine or wrist fracture. When risk of any fracture was assessed with warfarin use, no association was found [HR for warfarin use ≥ 1 year 0.92 (95%CI 0.77, 1.10); HR for warfarin use ≥ 3 years 1.12 (95%CI 0.88, 1.43)].

CONCLUSIONS

Long-term warfarin use among elders with atrial fibrillation was not associated with increased risk of osteoporotic fractures and therefore does not appear to necessitate additional surveillance or prophylaxis.

Observation of 2p3d(1Po)→1s3d(1De) radiative transition in He-like Si, S, and Cl ions

We present an experimental determination of the 2p3d(1Po)→1s3d(1De) x-ray line emitted from He-like Si, S, and Cl projectile ions, excited in collisions with thin carbon foils, using a high-resolution bent-crystal spectrometer. A good agreement between the observation and state-of-the-art relativistic calculations using the multiconfiguration Dirac-Fock formalism including the Breit interaction and QED effects implies the dominance of fluorescent decay over the autoionization process for the 2p3d(^{1}P^{o}) state of He-like heavy ions. This is the first observation of the fluorescence-active doubly excited states in He-like Si, S, and Cl ions.

Ion-lithium collision dynamics studied with a laser-cooled in-ring target

We present a novel experimental tool allowing for kinematically complete studies of break-up processes of laser-cooled atoms. This apparatus, the 'MOTReMi,' is a combination of a magneto-optical trap (MOT) and a reaction microscope (ReMi). Operated in an ion-storage ring, the new setup enables us to study the dynamics in swift ion-atom collisions on an unprecedented level of precision and detail. In the inaugural experiment on collisions with 1.5  MeV/amu O(8+)-Li the pure ionization of the valence electron as well as the ionization-excitation of the lithium target was investigated.

The double electrostatic ion ring experiment: a unique cryogenic electrostatic storage ring for merged ion-beams studies

We describe the design of a novel type of storage device currently under construction at Stockholm University, Sweden, using purely electrostatic focussing and deflection elements, in which ion beams of opposite charges are confined under extreme high vacuum cryogenic conditions in separate "rings" and merged over a common straight section. The construction of this double electrostatic ion ring experiment uniquely allows for studies of interactions between cations and anions at low and well-defined internal temperatures and centre-of-mass collision energies down to about 10 K and 10 meV, respectively. Position sensitive multi-hit detector systems have been extensively tested and proven to work in cryogenic environments and these will be used to measure correlations between reaction products in, for example, electron-transfer processes. The technical advantages of using purely electrostatic ion storage devices over magnetic ones are many, but the most relevant are: electrostatic elements which are more compact and easier to construct; remanent fields, hysteresis, and eddy-currents, which are of concern in magnetic devices, are no longer relevant; and electrical fields required to control the orbit of the ions are not only much easier to create and control than the corresponding magnetic fields, they also set no upper mass limit on the ions that can be stored. These technical differences are a boon to new areas of fundamental experimental research, not only in atomic and molecular physics but also in the boundaries of these fields with chemistry and biology. For examples, studies of interactions with internally cold molecular ions will be particular useful for applications in astrophysics, while studies of solvated ionic clusters will be of relevance to aeronomy and biology.

Does dietary protein reduce hip fracture risk in elders? The Framingham Osteoporosis Study

Association between dietary protein and fracture risk is unclear. We examined association between energy-adjusted protein intake and hip fracture risk in elders. The risk of hip fracture was reduced in upper quartiles of protein intake when compared with lowest quartile.

INTRODUCTION

Studies of the association between dietary protein intake and hip fracture risk are conflicting. Therefore, we examined protein intake and hip fracture risk in a population-based group of elderly men and women.

METHODS

Five hundred seventy-six women and 370 men from the Framingham Osteoporosis Study with no previous history of hip fracture completed Food Frequency Questionnaires. Energy-adjusted protein intake was evaluated as a continuous variable and as quartiles. Incidence rates and hazard ratios were calculated, adjusting for age, BMI, sex, and energy intake.

RESULTS

Among 946 participants (mean age 75 years), mean protein intake was found to be 68 gm/d. Increased protein intake was associated with a decreased risk of hip fracture compared to those in the lowest quartile of protein intake (Q2 HR = 0.70, Q3 HR = 0.56, and Q4 HR = 0.63; all p values ≥ 0.044), p for trend was 0.07. When a threshold effect was considered (Q2-4 vs Q1), intakes in the higher quartiles combined were associated with a significantly lower risk for hip fracture (HR = 0.63; p = 0.04).

CONCLUSION

Our results are consistent with reduced risk of hip fracture with higher dietary protein intake. Larger prospective studies are needed to confirm and extend this finding in elderly men and women.