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Dive into the research topics where David Levartovsky is active.

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Featured researches published by David Levartovsky.


Annals of the Rheumatic Diseases | 2008

Vaccination against influenza in patients with rheumatoid arthritis: the effect of rituximab on the humoral response

S Oren; M Mandelboim; Yolanda Braun-Moscovici; Daphna Paran; J Ablin; Irina Litinsky; D Comaneshter; David Levartovsky; Ella Mendelson; R Azar; Irena Wigler; Alexandra Balbir-Gurman; Dan Caspi; Ori Elkayam

Objective: To assess the effect of rituximab on the efficacy and safety of influenza virus vaccine in patients with rheumatoid arthritis (RA). Methods: The study group comprised patients with RA treated with conventional disease-modifying drugs with or without rituximab. Split-virion inactivated vaccine containing 15 μg haemagglutinin/dose of B/Shanghai/361/02 (SHAN), A/New Caledonian/20/99 (NC) (H1N1) and A/California/7/04 (CAL) (H3N2) was used. Disease activity was assessed by the number of tender and swollen joints, duration of morning stiffness and evaluation of pain on the day of vaccination and 4 weeks later. CD19-positive cell levels were assessed in rituximab-treated patients. Haemagglutination inhibition (HI) antibodies were tested and response was defined as a greater than fourfold rise 4 weeks after vaccination or seroconversion in patients with a non-protective baseline level of antibodies (<1/40). Geometric mean titres (GMT) were calculated in all subjects. Results: The participants were divided into three groups: RA (n = 29, aged 64 (12) years), rituximab-treated RA (n = 14, aged 53 (15) years) and healthy controls (n = 21, aged 58 (15) years). All baseline protective levels of HI antibodies and GMT were similar. Four weeks after vaccination, there was a significant increase in GMT for NC and CAL antigens in all subjects, but not for the SHAN antigen in the rituximab group. In rituximab-treated patients, the percentage of responders was low for all three antigens tested, achieving statistical significance for the CAL antigen. Measures of disease activity remained unchanged. Conclusion: Influenza virus vaccine generated a humoral response in all study patients with RA and controls. Although the response was significantly lower among rituximab-treated patients, treatment with rituximab does not preclude administration of vaccination against influenza.


Journal of Immunology | 2007

The Involvement of CD44 and Its Novel Ligand Galectin-8 in Apoptotic Regulation of Autoimmune Inflammation

Lora Eshkar Sebban; Denise Ronen; David Levartovsky; Ori Elkayam; Dan Caspi; Suhail Aamar; Howard Amital; Alan Rubinow; Ira Golan; David Naor; Yehiel Zick; Itshak Golan

The synovial fluid (SF) cells of rheumatoid arthritis (RA) patients express a specific CD44 variant designated CD44vRA. Using a cellular model of this autoimmune disease, we show in this study that the mammalian lectin, galectin-8 (gal-8), is a novel high-affinity ligand of CD44vRA. By affinity chromatography, flow cytometry, and surface plasmon resonance, we demonstrate that gal-8 interacts with a high affinity (Kd, 6 × 10−9 M) with CD44vRA. We further demonstrate that SF cells from RA patients express and secrete gal-8, to a concentration of 25–65 nM, well within the concentration of gal-8 required to induce apoptosis of SF cells. We further show that not all gal-8 remains freely soluble in the SF and at least part forms triple complexes with CD44 and fibrinogen that can be detected, after fibrinogen immunoprecipitation, with Abs against fibrinogen, gal-8 and CD44. These triple complexes may therefore increase the inflammatory reaction by sequestering the soluble gal-8, thereby reducing its ability to induce apoptosis in the inflammatory cells. Our findings not only shed light on the receptor-ligand relationships between CD44 and gal-8, but also underline the biological significance of these interactions, which may affect the extent of the autoimmune inflammatory response in the SF of RA patients.


The American Journal of Medicine | 1998

Clinical and immunological study of 7 patients with minocycline-induced autoimmune phenomena

Ori Elkayam; David Levartovsky; Chaim Brautbar; Michael Yaron; Michael Burke; Nurit Vardinon; Dan Caspi

PURPOSE Prolonged treatment with minocycline for acne vulgaris has been associated with the development of arthralgia, arthritis, and other autoimmune phenomena. We characterized the clinical, laboratory, and immunological profiles of seven patients with this syndrome. SUBJECTS AND METHODS Clinically the patients were studied with special emphasis on prior minocycline treatment, presenting symptoms, physical findings, course, and outcome. Laboratory tests included fluorescent antinuclear and antineutrophil cytoplasmic (ANCA) antibodies, as well as antibodies to myeloperoxidase, bactericidal permeability increasing protein, elastase, cathepsin G, lactoferrin, cardiolipin, and histone. RESULTS All 7 patients presented with polyarthritis or arthralgia, morning stiffness, and fever after 6 to 36 months of minocycline treatment. The skin was involved in five patients (three with livedo reticularis and two with subcutaneous nodules). Two patients had chronic active hepatitis. Increased titers of perinuclear ANCA (p-ANCA) were detected in all seven patients; five patients had fluorescent antinuclear antibodies, two had antihistone autoantibodies and one had anticardiolipin antibodies. Antigenic characterization of p-ANCA disclosed antibodies to bactericidal permeability increasing protein in one patient, to elastase in three patients, and to cathepsin G in five patients. Symptoms resolved in five patients upon discontinuation of minocycline; the other two patients were treated with corticosteroids and also achieved remissions. CONCLUSION Minocycline-induced autoimmune syndrome is characterized by reversible polyarthralgia or arthritis, morning stiffness, fever, frequent skin involvement, occasional chronic active hepatitis, and increased titers of p-ANCA with various minor p-ANCA-related antigens.


Arthritis Care and Research | 2011

Efficacy and safety of vaccination against pandemic 2009 influenza A (H1N1) virus among patients with rheumatic diseases.

Ori Elkayam; Sharon Amir; Ella Mendelson; Mitchell J. Schwaber; Itamar Grotto; Jonathan Wollman; Uri Arad; Ayelet Brill; Daphna Paran; David Levartovsky; Irena Wigler; Dan Caspi; Michal Mandelboim

To assess the efficacy and safety of vaccination against pandemic H1N1 virus in patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), psoriatic arthritis (PsA), and ankylosing spondylitis (AS) compared with healthy controls.


Autoimmunity | 2005

Autoantibodies profile of rheumatoid arthritis patients during treatment with infliximab

Ori Elkayam; Michael Burke; Nurit Vardinon; Vera Zakut; Ronit Ben Yitzhak; Daphna Paran; David Levartovsky; Irena Litinsky; Dan Caspi

Purpose: Therapy with TNFα blocking agents has been associated with increased rate of anti-nuclear antibodies (ANA) and rare cases of lupus like syndromes. Our aim was to prospectively analyze a wide array of autoantibodies in rheumatoid arthritis (RA) patients before and 14 weeks after starting infliximab. Material and Methods: In this study, 26 consecutive active RA patients participated. All treated with infliximab at a dosage of 3 mg/kg on week 0, 2, 6 and every 8 weeks, along with weekly low dose methotrexate. Patients were evaluated at week 0 and 14. Clinical assessment included the number of tender and swollen joints, duration of morning stiffness, adverse events (AE) (including SLE-like) and ESR. Sera were collected before the 1st infusion of infliximab at week 0 and 14. The autoantibodies studied were: fluorescent ANA, anti-double-stranded-DNA (anti-ds-DNA), IgG and IgM anti-cardiolipin (ACA), anti-histone- H1 and C (H1, H2A, H2B, H3, H4), anti-SSA, -SSB, -ENA, -scleroderma 70, -thyroid peroxidase (TPO) and -neutrophilic cytoplasmatic (ANCA) antibodies. Results: Of 26 patients, 17 were women. A significant decrease in duration of morning stiffness, number of tender and swollen joints and ESR were observed between week 0 and 14. During follow up (mean of 20.5±7.3 months), 9 patients stopped infliximab due to inefficacy or AE (most of them after the 4th infusion). Two patients developed lupus-like phenomena. ANA was found positive at baseline in 7 out of 26 patients. In 5 of them, an increase in the titer of ANA was observed at week 14. ANA negative turned positive for 8 patients. A significant increase of anti-cardiolipin (ACA)-IgM levels was observed in 8 patients and of ACA-IgG in 6, in parallel with ANA seroconversion. The mean level of anti-double-stranded-DNA (anti-ds-DNA) -IgG significantly increased from 66±33 to 93±68 IU/ml, in 4 patients to pathological levels. Four patients demonstrated an increase in anti-histone H1. Levels of ANCA, anti-ENA, -SSA, -SSB, -RNP, -scleroderma70 and -thyroid peroxidase (TPO) were negative in all patients and remained unchanged during the study. Cessation of treatment with infliximab was found to be associated with the appearance of ANA. Conclusion: An increased titer or a new appearance of ANA was observed in 12 out of 26 patients. The main autoantibodies found were anti-ds-DNA, ACA-IgM and -IgG and anti-histone. In our cohort, the appearance of some autoantibodies seemed to predict late cessation of treatment.


Annals of the Rheumatic Diseases | 2006

Cardiac dysfunction in patients with systemic lupus erythematosus and antiphospholipid syndrome

Daphna Paran; Dan Caspi; David Levartovsky; Ori Elkayam; Ilana Kaufman; Irena Litinsky; Gad Keren; Bella Koifman

Objective: To comparatively assess the parameters of systolic and diastolic cardiac function in patients with systemic lupus erythematosus (SLE) and antiphospholipid syndrome (APS). Methods: Consecutive patients (n = 74) who were free of cardiovascular symptoms were divided into four groups: (1) SLE (n = 23); (2) SLE with antiphospholipid antibodies (aPL; n = 18); (3) SLE with APS (n = 20); and (4) primary antiphospholipid syndrome (PAPS; n = 13). Pulsed, continuous, colour Doppler echocardiography, and M-mode and B-mode studies were performed. Results: Left ventricular end diastolic and end systolic dimensions were higher in SLE as compared with patients with PAPS (p = 0.022 and 0.022, respectively), with a trend towards a lower fractional shortening in SLE (p = 0.07), suggesting systolic dysfunction. Parameters of diastolic function were more impaired in patients with APS, reflected by lower left ventricular and right ventricular E wave to A wave (E:A) ratios in patients with APS (groups 3, 4) compared with those without APS (groups 1, 2; 1.15 (0.40) v 1.49 (0.43), p = 0.001 and 1.19 (0.31) v 1.49 (0.41), p = 0.001, respectively) and a more prolonged left ventricular isovolumic relaxation time (IVRT; 94.2 (24.6) v 84.4 (17) ms, respectively, p = 0.055). Patients with APS were older than those without APS (47.12 (14.86) v 34.29 (12.6), p = 0.0001). Patients with SLE were younger than those with PAPS (38.19 (14.68) v 48.53 (13.97), p = 0.023). Conclusion: Abnormal echocardiographic findings were detected frequently in asymptomatic patients with SLE or PAPS. Although patients with SLE were younger, left ventricular systolic function was more impaired in patients with SLE compared with those with PAPS, whereas left ventricular and right ventricular diastolic function, as reflected by IVRT and E:A ratios, were significantly more impaired in patients with APS.


Rheumatology International | 2004

Anemia, serum vitamin B12, and folic acid in patients with rheumatoid arthritis, psoriatic arthritis, and systemic lupus erythematosus

Refael Segal; Yehuda Baumoehl; Ori Elkayam; David Levartovsky; Irena Litinsky; Daphna Paran; Irena Wigler; Beni Habot; Arthur Leibovitz; Ben Ami Sela; Dan Caspi

ObjectiveAlthough anemia is frequent in inflammatory rheumatic diseases, data regarding vitamin B12 status is scarce. The purpose of this study was to analyze the incidence and nature of B12 and folic acid (FA) deficiencies in a cohort of rheumatic patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and systemic lupus erythematosus (SLE).MethodsLevels of B12, FA, and parameters of anemia were recovered or examined in 276 outpatients. In those with recent findings of low serum B12 levels, further studies of serum homocysteine (Hcy) and urine methylmalonic acid (MMA) levels were performed.ResultsThe incidence of anemia was high: 49%, 46%, and 35%, in RA, SLE, and PsA, respectively. Low levels of serum B12 were also frequent (24%), with almost similar occurrence in the three disease groups. Deficiency in FA was rare (<5%). Mean levels of both vitamins did not differ significantly among the three groups. No correlation between serum B12 levels and anemia was found. In the 15 patients with recently detected low B12 levels, Hcy and MMA were evaluated before and following B12 therapy. In ten of them, baseline Hcy levels were high, while MMA was increased in one patient only. Response to B12 administration, i.e., a decrease in Hcy and/or MMA levels, was noticed in four patients only, suggesting that only 26% of the low-serum-B12 patients had true B12 deficiency.ConclusionsThe incidences of anemia and decreased serum B12 levels were high in these three groups of rheumatic patients. However, true tissue deficiency seems to be much rarer.


Metabolomics | 2012

Urine metabolomics reveals novel physiologic functions of human aldehyde oxidase and provides biomarkers for typing xanthinuria

Hava Peretz; David G. Watson; Gavin Blackburn; Tong Zhang; Ayala Lagziel; Meirav Shtauber-Naamati; Tova Morad; Elena Keren-Tardai; Victoria Greenshpun; Sali Usher; Hanna Shalev; Daniel Landau; David Levartovsky

Classical xanthinuria is a rare inherited metabolic disorder caused by either isolated xanthine dehydrogenase (XDH) deficiency (type I) or combined XDH and aldehyde oxidase (AO) deficiency (type II). XDH and AO are evolutionary related enzymes that share a sulfurated molybdopterin cofactor. While the role of XDH in purine metabolism is well established, the physiologic functions of AO are mostly unknown. XDH and AO are important drug metabolizing enzymes. Urine metabolomic analysis by high pressure liquid chromatography and mass spectrometry of xanthinuric patients was performed to unveil physiologic functions of XDH and AO and provide biomarkers for typing xanthinuria. Novel endogenous products of AO, hydantoin propionic acid, N1-methyl-8-oxoguanine and N-(3-acetamidopropyl) pyrrolidin-2-one formed in the histidine, nucleic acid and spermidine metabolic pathways, respectively, were identified as being lowered in type II xanthinuria. Also lowered were the known AO products, N1-methyl-2-pyridone-5-carboxamide and N1-methyl-4-pyridone-5-carboxamide in the nicotinamide degradation pathway. In contrast to the KEGG annotations, the results suggest minor role of human AO in the conversion of pyridoxal to pyridoxate and gentisaldehyde to gentisate in the vitamin B6 and tyrosine metabolic pathways, respectively. The perturbations in purine degradation due to XDH deficiency radiated further from the previously known metabolites, uric acid, xanthine and hypoxanthine to guanine, methyl guanine, xanthosine and inosine. Possible pathophysiological implications of the observed metabolic perturbations are discussed. The identified biomarkers have the potential to replace the allopurinol-loading test used in the past to type xanthinuria, thus facilitating appropriate pharmacogenetic counseling and gene directed search for causative mutations.


Annals of the Rheumatic Diseases | 2006

Evoked potential studies in the antiphospholipid syndrome: differential diagnosis from multiple sclerosis

Daphna Paran; Joab Chapman; Amos D. Korczyn; Ori Elkayam; Olga Hilkevich; Galina B. Groozman; David Levartovsky; Irena Litinsky; Dan Caspi; Yoram Segev; Vivian E. Drory

Background: The CNS manifestations of the antiphospholipid syndrome (APS) can mimic multiple sclerosis both clinically and radiologically. Objective: To compare evoked potential studies in APS patients and patients with multiple sclerosis with similar neurological disability. Methods: 30 APS patients with CNS manifestations and 33 patients with definite multiple sclerosis and similar neurological disability underwent studies of visual evoked potentials (VEP), somatosensory evoked potentials (SSEP) in the upper and lower limbs (UL, LL), and sympathetic skin responses (SSR) in the upper and lower limbs. Results: The neurological manifestations in the APS patients included stroke (n = 17), transient ischaemic attacks (n = 10), and severe headache with multiple white matter lesions on brain MRI (n = 3). Abnormal SSEP (LL), and SSR (UL; LL) were seen in APS patients (37%, 27%, and 30%, respectively) but VEP and UL SSEP were rarely abnormal (10% and 6%, respectively in APS v 58% and 33% in multiple sclerosis; p = 0.0005, p = 0.008). Mean VEP latencies were more prolonged in multiple sclerosis (116 ms v 101 ms, p<0.001). Only one APS patient had abnormal findings in all three evoked potential studies, compared with seven patients in the multiple sclerosis group (p = 0.04) Conclusions: Abnormal VEPs are uncommon in APS in contrast to multiple sclerosis. Coexisting abnormalities in all other evoked potentials were similarly rare in APS. In patients with brain MRI findings compatible either with multiple sclerosis or APS, normal evoked potential tests, and especially a normal VEP, may support the diagnosis of APS.


Pain Research & Management | 2012

Evaluation of leptin levels among fibromyalgia patients before and after three months of treatment, in comparison with healthy controls.

Jacob N. Ablin; Natalia Aronov; Ilan Shimon; Hannah Kanety; Clara Pariente; Valerie Aloush; Ori Elkayam; David Levartovsky

BACKGROUND Leptin, an adipocyte-produced cytokine, interacts with various hormones, including those of the hypothalamic-pituitary-adrenal axis. Fibromyalgia is a syndrome characterized by widespread pain accompanied by tenderness. The pathogenesis involves a disturbance in pain processing and transmission by the central nervous system, leading to a general increase in pain perception. OBJECTIVES To analyze potential changes in leptin levels among female fibromyalgia patients compared with healthy controls, and to evaluate the changes in leptin levels during treatment. METHODS Sixteen female fibromyalgia patients were recruited. Patients underwent clinical evaluation, physical examination, including manual dolorimetry, and were evaluated regarding quality of life, pain, fatigue, anxiety and depression. Plasma leptin levels were determined by ELISA. Patients were offered standard treatment for fibromyalgia. Clinical evaluation and leptin determination were repeated after three months. RESULTS No significant difference was observed between leptin levels among fibromyalgia patients and controls; no significant correlation was observed between leptin levels and clinical parameters reflecting fibromyalgia severity; and no significant change was observed in leptin levels over three months of treatment. These results did not change after adjustment of leptin levels for body mass index values. CONCLUSIONS The results of the present study do not support the existence of a significant relationship between leptin and fibromyalgia pathogenesis. Increasing the sample size or examining the interaction between leptin and additional hormones⁄mediators of metabolism and body weight control may yet uncover significant information in this field.

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Dan Caspi

Tel Aviv Sourasky Medical Center

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Daphna Paran

Tel Aviv Sourasky Medical Center

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Irena Wigler

Tel Aviv Sourasky Medical Center

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Jonathan Wollman

Tel Aviv Sourasky Medical Center

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Suhail Aamar

Hebrew University of Jerusalem

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Alan Rubinow

Hebrew University of Jerusalem

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