Biomedical subjects

O Meyer

Publications and source records attributed to O Meyer.

At least 19 recordsLinked to original sources

PubMed2006

Association between an endoglin gene polymorphism and systemic sclerosis-related pulmonary arterial hypertension.

UNLABELLED: Systemic sclerosis (SSc) is a connective tissue disorder characterized by early generalized microangiopathy with disturbed angiogenesis. Endoglin gene (ENG) encodes a transmembrane glycoprotein which acts as an accessory receptor for the transforming growth factor-beta (TGF-beta) superfamily, and is crucial for maintaining vascular integrity. A 6-base insertion in intron 7 (6bINS) of ENG has been reported to be associated with microvascular disturbance. OBJECTIVES: Our objective was to investigate the relationship between 6bINS and the vascular complication pulmonary arterial hypertension (PAH) in SSc in a French Caucasian population. METHODS: Two hundred eighty SSc cases containing 29/280 having PAH diagnosed by catheterism were compared with 140 patients with osteoarthritis. Genotyping was performed by polymerase-chain-reaction-based fluorescence and direct sequencing of genomic DNA. RESULTS: The polymorphism was in Hardy-Weinberg equilibrium. We observed a significant lower frequency of 6bINS allele in SSc patients with associated PAH compared with controls [10.3 vs 23.9%, P = 0.01; odds ratio (OR) 0.37, 95% confidence interval (CI) 0.15-0.89], and a trend in comparison with SSc patients without PAH (10.3 vs 20.3%, P = 0.05; OR: 0.45, 95% CI: 0.19-1.08). Genotypes carrying allele 6bINS were also less frequent in SSc patients with PAH than in controls (20.7 vs 42.9%, P = 0.02). CONCLUSIONS: Thus the frequency of 6bINS differs between SSc patients with or without PAH, suggesting the implication of ENG in this devastating vascular complication of SSc.

Adult↗

PubMed2006

Replacement of intravenous administration of anti-D by subcutaneous administration in patients with autoimmune thrombocytopenia.

Intravenous (IV) administration of anti-D in patients with autoimmune thrombocytopenia (AITP) may result in severe hemolysis and even death. Over a 3-year period, we gave anti-D only subcutaneously (SC), and none of our patients have developed any acute adverse reaction. Most importantly, SC delivery of anti-D produces largely the same beneficial effect as obtained by IV anti-D. We recommend replacement of IV administration of anti-D by SC administration in AITP.

Adult↗

PubMed2006

Impact of pain in health related quality of life of patients with systemic sclerosis.

OBJECTIVES: Systemic sclerosis (SSc) has an heterogenous clinical pattern, with variable organ involvement and degrees of severity. Like in other rheumatic diseases, the self-questionnaires have been used to evaluate SSc globally. The aim of the study is as to evaluate the quality of life (QoL) in patients with either diffuse or limited SSc, and to examine the impact of pain on the QoL scores. METHODS: Patients with SSc, either diffuse or limited SSc, were included in a cross-sectional study. The QoL was evaluated with the short-form 36 (SF-36) and the functional repercussion with the SSc-modified Health Assessment Questionnaire (S-HAQ). RESULTS: A total of 89 patients (67 with diffuse and 22 with limited SSc) were included. The SF-36 score values were lower in SSc patients than those reported in the general population. The physical component scores (PCS) of the SF-36 was significantly worse in diffuse compared with limited SSc (P < 0.05). The PCS was significantly negatively related to the number of clinical manifestations (ANOVA, P < 0.0001). The mental component score (MCS) was not influenced by the type of SSc or the number of clinical manifestations presented by the patient. The QoL of SSc patients was highly correlated with pain (R = 0.69) and disability (R = 0.70). Interestingly, the QoL of SSc patients was only slightly correlated with cutaneous (R = 0.42) and pulmonary involvement (R = 0.57). CONCLUSION: The QoL of patients with SSc is strongly influenced by the type of SSc, the burden of clinical manifestations, the functional disability and by the pain, whatever its cause. The treatment of pain should be considered as priority to improve the QoL of SSc patients.

Adolescent↗

PubMed2006

Lack of association between the protein tyrosine phosphatase non-receptor 22 (PTPN22)*620W allele and systemic sclerosis in the French Caucasian population.

The minor allele of the R620W missense single-nucleotide polymorphism (SNP; rs2476601) in the PTPN22 (protein tyrosine phosphatase non-receptor 22) gene has been reported to be associated with multiple autoimmune diseases, including type 1 diabetes, systemic lupus erythematosus, rheumatoid arthritis, juvenile idiopathic arthritis, autoimmune thyroiditis and vitiligo. Systemic sclerosis (SSc) is a connective tissue disease with some autoimmune abnormalities. The aim of our study was to test for association of the PTPN22*620W allele with SSc in a French Caucasian cohort with a case-control study of 121 patients with SSc and 103 controls. All patients and controls were genotyped for the PTPN22*R620W SNP. No association was found between the PTPN22*620W allele and SSc (7% v 9.2%, p = 0.39). The frequency of genotypes carrying at least one 620W allele was similar in both groups (13% v 17%, p = 0.38). The PTPN22*620W allele was also not associated with autoantibody patterns. Thus, the PTPN22*R620W polymorphism cannot be regarded as a genetic susceptibility factor for SSc in the French Caucasian population.

Adult↗

PubMed2006

A simple and practical agglutination assay for human leucocyte antigen-B27 typing.

BACKGROUND AND OBJECTIVES: The human leucocyte antigen (HLA) B27 is the most frequently typed single antigen that is associated with diseases. Here, we describe a simple and rapid particle agglutination assay (PaGIA) for HLA-B27 typing. MATERIALS AND METHODS: Superparamagnetic particles were coated with a monoclonal antibody to HLA-B27 and subsequently used for testing. Anticoagulated whole-blood samples were obtained from healthy blood donors (n = 194) with known HLA patterns and from patients (n = 51) who had been typed positive for HLA-B27 by flow cytometry. RESULTS: The particles agglutinated only after incubation with HLA-27-positive blood samples, using the ID-microtyping system. Positive reactions were clearly distinguishable from negative reactions in all samples tested. Flow cytometric HLA-B27 typing revealed an indeterminate result in one patient. CONCLUSIONS: The new HLA-B27 PaGIA is suitable for rapid typing of HLA-B27. The assay is simple and easy to perform, and can be implemented in any routine laboratory.

Agglutination Tests↗

PubMed2006

A novel antigen-specific capture assay for the detection of platelet antibodies and HPA-1a phenotyping.

BACKGROUND AND OBJECTIVES: The antigen-specific assays currently used for the laboratory investigation of platelet antibodies and antigens are technically complex and cannot be used in most routine laboratories. Here, we describe a simple antigen-specific capture assay (ASCA) for the detection of serum platelet antibodies and for human platelet antigen-1a (HPA-1a) phenotyping. MATERIALS AND METHODS: For the detection of platelet antibodies, platelets from healthy blood donors were incubated with biotinylated monoclonal antibodies to platelet glycoprotein complexes (GP), then solubilized and mixed with superparamagnetic streptavidin particles. Serum samples from patients with autoimmune thrombocytopenia (n = 39), from patients with platelet alloantibodies (6 HPA-1a, 1 HPA-2b, 1 HPA-3a, 6 HPA-5b), and from healthy blood donors (n = 70), were tested. All serum samples from the patients were investigated in parallel by the indirect monoclonal antibody-specific immobilization of platelet antigen assay (MAIPA). For HPA-1a phenotyping, superparamagnetic particles were coated with a monoclonal antibody to HPA-1a and mixed with diluted whole blood samples from healthy blood donors (n = 139), who had previously been genotyped for platelet alloantigens. Results The indirect MAIPA detected autoantibodies in 18%, and the direct MAIPA in 50% of patients tested. In contrast, the new ASCA demonstrated positive results in 77% of patients. All tested alloantibodies reacted positive by the ASCA, and all serum samples from healthy blood donors were negative. The results of HPA-1a phenotyping were in concordance with those of genotyping in all cases. CONCLUSION: In our opinion, the ASCA is easy to perform and much more sensitive than the currently available antigen-specific assays for the detection of platelet antibodies.

Antigens, Human Platelet↗

PubMed2005

Clinical practice decision tree for the choice of the first disease modifying antirheumatic drug for very early rheumatoid arthritis: a 2004 proposal of the French Society of Rheumatology.

OBJECTIVE: To elaborate a clinical practice decision tree for the choice of the first disease modifying antirheumatic drug (DMARD) for untreated rheumatoid arthritis of less than six months' duration. METHODS: Four steps were employed: (1) review of published reports on DMARD efficacy against rheumatoid arthritis; (2) inventory of the information available to guide DMARD choice; (3) selection of the most pertinent information by 12 experts using a Delphi method; and (4) choice of DMARDs in 12 clinical situations defined by items selected in step 3 (28 joint disease activity score (DAS 28): < or =3.2; >3.2 and < or =5.1; >5.1; rheumatoid factor status (positive/negative); structural damage (with/without)-that is, 3 x 2 x 2). Thus, multiplied by all the possible treatment pairs, 180 scenarios were obtained and presented to 36 experts, who ranked treatment choices according to the Thurstone pairwise method. RESULTS: Among the 77 items identified, 41 were selected as pertinent to guide the DMARD choice. They were reorganised into five domains: rheumatoid arthritis activity, factors predictive of structural damage; patient characteristics; DMARD characteristics; physician characteristics. In the majority of situations, the two top ranking DMARD choices were methotrexate and leflunomide. Etanercept was an alternative for these agents when high disease activity was associated with poor structural prognosis and rheumatoid factor positivity. CONCLUSIONS: Starting with simple scenarios and using the pairwise method, a clinical decision tree could be devised for the choice of the first DMARD to treat very early rheumatoid arthritis.

Antirheumatic Agents↗

PubMed2005

Human platelet antigen genotyping by using sequence-specific primers and the particle gel agglutination assay.

BACKGROUND AND OBJECTIVES: Polymerase chain reaction using sequence-specific primers (PCR-SSP) is currently the most widely used technique for human platelet antigen (HPA) genotyping. Here, we describe a novel particle gel-agglutination technique for simplified visualization of the amplified products. MATERIALS AND METHODS: Biotinylated primers were used to amplify HPA-1, -2, -3, -4, -5, -6, and -15, and the PCR products were incubated with streptavidin particles. Fluorescein isothiocyanate (FITC)-labelled primers [amplifying a fragment of the human growth hormone (HGH) gene] and anti-FITC-coated particles were used as internal controls. Agglutination of the particles in or on top of the gel indicated specific amplification. A total of 100 samples from blood donors was tested by using this new technique and a standard PCR-SSP protocol. RESULTS: The use of biotinylated sequence-specific primers resulted in PCR products that agglutinated streptavidin particles, and the FITC-labelled HGH primers led to agglutination of anti-FITC-coated particles. Negative reactions were clearly distinguishable from positive reactions. The results of the particle gel agglutination method were in concordance with those of the electrophoretic visualization in all cases tested. CONCLUSIONS: The new particle agglutination method is reliable and easy to use.

Agglutination Tests↗

PubMed2005

Growth differences of male and female Göttingen minipigs during ad libitum feeding: a pilot study.

Even though minipigs have been used in biomedical research for nearly half a century now, no specific nutrient requirements are available. For that reason a series of studies into the nutrient requirements of Göttingen minipigs were carried out. Firstly, a pilot study was carried out to determine the ad libitum feed intake (FI) during growth, as a reference for later feed restriction studies. Four male and four female minipigs were fed two types of diet, one standard pig diet (20.6% crude protein; 11.7% crude fat; 13.5 mJ/kg DM metabolizable energy) and one diet specially designed for minipigs (12.0% crude protein; 2.9% crude fat; 11.9 MJ/kg DM metabolizable energy). When fed ad libitum for 13 weeks, female Göttingen minipigs developed a significantly (P<0.05) higher body weight (BW) than males (27.4 vs 16.6 kg) on either diet. The large difference in growth between male and female Göttingen minipigs did not appear to be the result from differences in metabolizable energy intake. Metabolizable energy intake of male and female Göttingen minipigs could be predicted by ME=1877 kJxBW(0.61). Both male and female Göttingen minipigs became obese when fed ad libitum, defined by relative backfat thickness. Relative backfat thickness ranged from 5 to 13 cm/100 kg. Females had thicker relative backfat layers than males. Remarkably, no large changes in haematology and clinical chemistry occurred in ad libitum fed Göttingen minipigs as compared to reference values, and no abnormalities other than enlarged fat reserves were observed at necropsy. Apparently, Göttingen minipigs do not restrain FI voluntarily, and restricted feeding is therefore indicated to prevent obesity.

Aging↗

PubMed2004

Prevalence of anti-cyclic citrullinated peptide and anti-keratin antibodies in patients with primary Sjögren's syndrome.

OBJECTIVE: To investigate the prevalence of anti-cyclic citrullinated peptide (anti-CCP) and anti-keratin antibodies (AKA) in patients with primary Sjögren's syndrome. METHODS: 149 patients with a diagnosis of primary Sjögren's syndrome according to the European/American consensus criteria were recruited from three French medical centres. The presence of anti-CCP was determined by enzyme linked immunosorbent assay and of AKA antibodies by indirect immunofluorescence. Radiographs of hands and feet were evaluated at the time of anti-CCP analysis. RESULTS: Six patients with radiological erosions and nine patients with non-erosive arthritis fulfilling ACR criteria for rheumatoid arthritis were thought to have rheumatoid arthritis and secondary Sjögren's syndrome, while 134 were considered to have primary Sjögren's syndrome (mean (SD) disease duration, 11.1 (6.6) years). Of these, 80 tested positive for IgM rheumatoid factor (RF) (59%), 10 (7.5%) for anti-CCP, 7 (5.2%) for AKA, and 5 (3.7%) for both anti-CCP and AKA. There was no difference in clinical and biological features, including prevalence of RF, between anti-CCP positive and negative patients. The nine Sjögren patients with non-erosive arthritis, fulfilling ACR criteria for rheumatoid arthritis, were all CCP positive. Their response to disease modifying antirheumatic drugs could be different from classical rheumatoid patients. CONCLUSIONS: Most patients with primary Sjögren's syndrome are negative for AKA and anti-CCP, but positive test results should not rule out this diagnosis. Anti-CCP positive patients, who may be prone to developing rheumatoid arthritis, require cautious clinical and radiographic follow up.

Adult↗

PubMed2004

Validation of French version of the Scleroderma Health Assessment Questionnaire (SSc HAQ).

The modified Scleroderma Health Assessment Questionnaire (SSc HAQ) is a functional score to assess systemic sclerosis (SSc) comprising the HAQ disease index (HAQ-DI) plus five specific visual analogue scales (VAS). Since it was validated in English-speaking patients only, its general use in any other language necessitates prior cross-cultural adaptation and validation. We designed this study to assess its value in French-speaking patients and to validate the French version according to international recommendations. We elaborated a French version using the "forward-backward" method. We then validated its psychometric properties with 100 consecutive SSc French-speaking patients who had undergone simultaneous clinical and paraclinical examination. In addition, we calculated the SSc HAQ score, a new outcome measure, which is obtained by pooling the eight domains from the HAQ-DI with the five organ VAS. Our study confirmed the psychometric properties of the SSc HAQ in non-English-speaking patients with (a) structural validity: the major component analysis, performed on the HAQ-DI and the five VAS, yielding a two-factor structure; (b) convergent validity: with high correlation coefficients between the SSc HAQ score and the physical component score of the SF-36 (r=-0.74, p<0.0001); (c) discriminant validity: the SSc HAQ score was better in patients with limited than with diffuse SSc (0.5+/-0.5 vs 1.1+/-0.7, respectively, p<0.0001) in relation to the number of clinical involvements; (d) reproducibility was high using the test-retest procedure (r=0.98). This study showed the value of the SSc HAQ, which is a simple, discriminant, reproducible self-administered questionnaire to evaluate French-speaking SSc patients. In addition, we suggest the use of a new outcome measure, the SSc HAQ score, to assess this systemic disease more accurately.

Disability Evaluation↗

PubMed2004

Repeated dose 28-day oral toxicity study in Wistar rats with a mixture of five pesticides often found as residues in food: alphacypermethrin, bromopropylate, carbendazim, chlorpyrifos and mancozeb.

Six dose groups of 8 male and female rats respectively received a daily dose equivalent to 0, 0.15, 0.006, 0.03, 0.15 or 0.3 mg/kg b.w./day chlorpyrifos (groups 1-6) and the last four dose groups (groups 3-6) received in addition daily doses equivalent to 18 mg/kg b.w./day alphacypermethrin, 30 mg/kg b.w./day bromopropylate, 45 mg/kg b.w./day carbendazim and 12.5 mg/kg b.w./day mancozeb for 28 days. Plasma acetylcholinesterase was significantly decreased in the groups 2, 5 and 6 males. Total white blood cell count was significantly lower in females of group 6. Total red blood cell count, haematocrite and haemoglobin concentration was significantly reduced in both male and female rats of groups 5 and 6. Relative liver weight was significantly increased in groups 3-6 male and female rats. Absolute thyroid gland weight was significantly increased in groups 3, 5 and 6 male rats and of groups 3-6 female rats, and relative thyroid gland weight was significantly increased in groups 2-6 male rats and of groups 3-6 female rats. Absolute thymus weight of groups 3-6 male and female rats and relative thymus weight of groups 3-6 male rats and groups 3 and 4 female rats was significantly decreased. A mild degree of centrilobular cell hypertrophy of the liver was seen in all male rats and of three female rats of group 6. In the thyroid gland follicular cell hypertrophy was present in one female in the control group and in six females and seven males of group 6. It was concluded that inhibition of acetylcholinesterase activity in plasma and brain by chlorpyrifos was not enhanced by co-administration of the other four pesticides. Effects were seen in liver, thyroid, thymus and blood in the combination groups. However, identification of the pesticide(s) responsible for these changes would require further studies of the individually pesticides as well as various combinations of the pesticides.

Acetylcholinesterase↗

PubMed2004

[Quality of life assessment with the MOS-SF36 in patients with systemic sclerosis].

OBJECTIVE: To investigate the metric properties and the validity of the Medical Outcome Study Short Form 36 (SF-36), a questionnaire to assess the quality of life, in patients with either diffuse or limited systemic sclerosis (SS), and to examine the effect of the disease on quality of life. METHODS: Cross sectional study of 86 patients with a SS (64 diffuse SS, 22 limited SS). Disease severity was assessed by clinical examination, pulmonary functional tests and Health Assessment Questionnaire (HAQ) modified for scleroderma. RESULTS: The SF-36 scores values were lower in diffuse than in limited sclérodermie systémique. The Physical Component Score was worse in patients with than without any clinical involvement. This score increased in relation with the number of clinical involvements. The quality of life of patients with SS was correlated to its functional repercussion. CONCLUSION: The quality of life in SS patients is correlated with the clinical severity of the disease. The use of SF-36 to measure the quality of life is useful for the clinical evaluation of patients with SS.

Adolescent↗

PubMed2004

Second generation anti-cyclic citrullinated peptide (anti-CCP2) antibodies can replace other anti-filaggrin antibodies and improve rheumatoid arthritis diagnosis.

We compared the diagnostic performance of anti-cyclic citrullinated peptide antibodies detected with second-generation enzyme immunoassay (anti-CCP2) with that of IgM-rheumatoid factor (RF), anti-perinuclear factor (APF), and anti-keratin antibodies (AKA). The sensitivity of anti-CCP2 was better than that of APF and AKA: they were detected in 25% rheumatoid arthritis (RA) patients without detectable APF or AKA. Their specificity, evaluated in other inflammatory rheumatic disease, was similar to that of APF and AKA. Despite the lower specificity, IgM-RF in combination with anti-CCP2 is interesting, as they do not completely overlap. Anti-CCP2 antibody detection seems to be a good alternative to other anti-filaggrin antibodies in the diagnosis of RA.

Arthritis, Rheumatoid↗

PubMed2004

Amlodipine-induced immune thrombocytopenia.

BACKGROUND AND OBJECTIVES: Drug-induced thrombocytopenia is a serious, but rare, side-effect of treatment with a number of drugs. In this report, we investigate the suspicion that amlodipine, a calcium-channel blocker, was responsible for immune thrombocytopenia in a 79-year-old patient. PATIENT AND METHODS: Our patient experienced two attacks of thrombocytopenic purpura after 10 years of treatment with amlodipine. Antibodies to platelets were tested by standard methods. RESULTS: Initially, the platelet count increased owing to treatment with prednisolone and intravenous immunoglobulin G, but decreased shortly after discontinuation of this treatment. The patient's serum was found to contain amlodipine-dependent antibodies to platelets, and he recovered after stopping the drug. CONCLUSIONS: Amlodipine can induce immune thrombocytopenia, which may strongly resemble autoimmune thrombocytopenia.

Aged↗

PubMed2004

Prognostic factors for remission in early rheumatoid arthritis: a multiparameter prospective study.

OBJECTIVE: To determine prognostic factors for remission in early rheumatoid arthritis. METHODS: 191 patients with rheumatoid arthritis whose disease duration was less than one year were followed up prospectively for five years. Remission, defined by a disease activity score (DAS) of <1.6, was used as the outcome measure. Baseline clinical, laboratory, genetic, and radiographic data (with radiographic scores determined by Sharp's method, modified by van der Heijde) were obtained. RESULTS: 48 patients (25.1%) fulfilled the remission criteria at the three year follow up visit, and 30 (15.7%) at three and five years. On univariate analysis by Fisher's exact test, remission at three years and persistent remission at five years were closely correlated with baseline DAS values, C reactive protein level, Ritchie score, health assessment questionnaire score, duration of morning stiffness, and to a lesser extent baseline total radiological scores and rheumatoid factor negativity. No significant correlation was found with sex, age, extra-articular manifestations, erythrocyte sedimentation rate, anti-cyclic citrullinated protein antibodies, anti-keratin antibodies, anti-HSP 90, anticalpastatin antibodies, antinuclear antibodies, or HLA-DRB1* genotypes. Logistic regression analysis showed that the baseline independent variables predictive of remission were low DAS, Ritchie score, morning stiffness duration, and total radiographic score. CONCLUSIONS: Baseline prognostic factors for remission in early rheumatoid arthritis were mainly clinical markers of disease activity and radiological scores.

Analysis of Variance↗

PubMed2004

[Platelet reactivity index by Grotemeyer].

In 1974 Wu and Hoak described a method for determining circulating platelet aggregates. This method was modified by Grotemeyer in 1983. The platelet reactivity index (PR) is based on the ratio of platelet aggregates in blood samples obtained in different buffer solutions. Platelet aggregates are resolved, when blood is sampled in EDTA-buffer, but remain fixed when EDTA-formalin-buffer is used. Generally, the PR is preferred, because in vitro manipulations of platelets are not necessary, and the results are estimated automatically. PR values above 1.05 are suspicious for elevated platelet aggregation. PR values above 1.2 indicate pathological changes in platelet aggregation. The PR is inexpensive (4.0 D ) and rapid to perform. PR-values were used successfully to identify non-responders to secondary prophylaxis with acetylsalicylic acid (ASA), i. e. patients suffering from stroke (33%) and after cardiac ischaemia (18%). Furthermore, elevated PR-values correlated significantly with the incidence of arterial thromboembolic complications. The PR correlated well in a own prospective study (drug monitoring) with values received from the retention test Homburg (RT-H) and the platelet function analyser (PFA-100). These data indicate that the values of the PR seems to be highly predictive for the evaluation of the ASA therapy. However, the PR is not suitable for the determination of ASA overdosage.

Blood Platelets↗

PubMed2003

Anti-TNF-alpha-induced systemic lupus syndrome.

Anti-TNF-alpha therapies are promising new strategies in the treatment of rheumatoid arthritis (RA). Despite good clinical efficacy and tolerance, the possible occurrence of drug-induced autoimmune disorders remains a matter of concern. Induction of antinuclear (ANA) and anti-DNA antibodies is observed in some patients treated with TNF-alpha inhibitors (anti- TNF-alpha antibodies) or soluble TNF-alpha receptor. Of concern is the possibility of induction of true lupus erythematosus by TNF blockers. Few cases without major organ involvement were reported to be associated with infliximab treatment that resolved after anti-TNF discontinuation. Only four cases have been described with the use of etanercept. We report a new case of infliximab-induced lupus syndrome and two new cases of etanercept-induced lupus syndrome in three patients with RA, all of whom had previous isolated positive ANA.

Adult↗