PubMed Health⌕ Search

Biomedical subjects

N Bernard

Publications and source records attributed to N Bernard.

At least 19 recordsLinked to original sources
PubMed1992

Restricted tissue reactivity of autoantibodies to a 64-kDa eye muscle membrane antigen in thyroid-associated ophthalmopathy.

We studied the tissue specificity of eye muscle (EM) membrane-reactive autoantibodies detected in the serum of patients with thyroid-associated ophthalmopathy (TAO). In preliminary studies, such antibodies were shown to react, in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting, with human thyroid (THY) and other human skeletal muscle (HSM) membrane antigens. We carried out absorption with human EM (HEM), THY, and HSM membranes of sera from patients with TAO and autoimmune thyroid disease without ophthalmopathy which reacted with one or more of 55-, 64-, and 95-kDa antigens in pig eye muscle (PEM) membrane in immunoblotting, the majority of which were also cytotoxic to HEM cells in an antibody-dependent cell-mediated cytotoxicity assay. In Western blotting, serum antibodies reactive with PEM membrane antigens of 55, 64, and 95 kDa were cross-absorbed by HEM, THY, and HSM but not by spleen or brain membranes and showed some species specificity, being absorbed by pig and human, but not bovine, EM membranes. When incubated with cultured HEM, THY, and HSM cells in vitro, autoantibodies in TAO sera immunoprecipitated a 64-kDa antigen from the first two tissues, but not from HSM, suggesting a specific binding to autoantigenic epitopes in HEM and THY. Sera from patients with TAO as well as those from patients with thyroid autoimmunity without ophthalmopathy immunoprecipitated a approximately 66-kDa protein, shown to be distinct from the 64-kDa antigen. The restricted immunological cross-reactivity of antibodies to a THY and HEM 64-kDa membrane antigen is discussed in the context of the association of ophthalmopathy with thyroid autoimmunity. Further experiments are needed to show whether autoantibodies to the 64-kDa eye muscle and thyroid shared antigen are cytotoxic, and thus likely to play a major role in the pathogenesis of the eye disease, or just markers of the orbital autoimmune process.

Adult↗
PubMed1992

Significance of antibodies reactive with a 64 kDa eye muscle membrane antigen in patients with thyroid autoimmunity.

SDS-polyacrylamide gel electrophoresis and Western blotting for antibodies reactive with a 64 kDa protein in pig eye muscle membrane was carried out in patients with lid lag and retraction, but no other signs of ophthalmopathy, associated with thyroid disease or nonimmunologic goiter and in patients with Graves' hyperthyroidism without ophthalmopathy who were studied prospectively to determine the relationship of eye muscle antibodies to clinical features of the ophthalmopathy as they appeared in this group of predisposed patients. Seventy-one percent of euthyroid patients with lid lag and retraction but no established ophthalmopathy had detectable serum antibodies to a 64 kDa eye muscle membrane protein. Much smaller proportions had antibodies to proteins of other MW. In normal subjects with previously detectable antibodies to a 64 kDa protein, serum titers, determined by carrying out immunoblotting at serum dilutions of 1:25-1:6400, were low (< or = 1:100) in all cases tested. On the other hand, titers were higher (1:200-1:6400) in 16 of 22 patients with established ophthalmopathy and in 5 of 7 patients with lid lag and retraction tested. Titers tended to be lower in patients with ophthalmopathy of > or = 3 years duration than in those of < or = 1 year duration. Antibody titers were low (1:25) in 6 of 7 patients with Graves' hyperthyroidism without evident eye disease tested. Antibodies to a 64 kDa eye muscle membrane protein were predictive of the development of ophthalmopathy in patients with Graves' hyperthyroidism studied prospectively for periods of 8-42 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Antibodies in the serum of patients with autoimmune thyroid disorders react with a recombinant 98 amino acid fragment of a full length 64 kDa eye muscle membrane protein which is also expressed in the thyroid.

We have tested sera from patients with autoimmune thyroid disorders with or without ophthalmopathy for immunoreactivity, in a dot blot assay, against a recombinant 98 amino acid fragment of a cloned 64 kDa protein, D1, which is expressed in human eye muscle and thyroid, in the form of a Lac Z fusion protein. Tests were positive in 19 out of 40 patients with established thyroid-associated ophthalmopathy (TAO), in 12 out of 21 patients with Graves' hyperthyroidism (GH) without clinically evident ophthalmopathy, in 5 out of 10 patients with thyroid autoimmunity and lid retraction but no other signs of ophthalmopathy, in 4 out of 23 patients with Hashimoto's thyroiditis (HT) without evident ophthalmopathy and in 2 out of 18 patients with benign adenoma or multinodular goitre, but in only 2 out of 37 normal subjects tested. SDS-polyacrylamide gel electrophoresis and Western blotting for an antibody reactive with a 64 kDa antigen in pig eye muscle membranes was also carried out on sera from patients with TAO and GH. While immunoblotting for antibodies reactive with a 64 kDa protein was more often positive in patients with TAO, in whom 58% had serum antibodies which reacted with a 64 kDa protein, this was not the case in patients with GH without eye signs in whom the prevalence of positive immunoblot tests was 35%. Overall there was a fairly close correlation between the two tests although there were many exceptions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Cell-mediated immunity to orbital tissue antigens in thyroid-associated ophthalmopathy determined using the leukocyte procoagulant activity assay.

While it is generally accepted that thyroid-associated ophthalmopathy (TAO), a progressive inflammatory disorder of the extraocular muscle and orbital connective tissue (OCT), is immunologically mediated the nature of the underlying abnormalities is poorly understood. Although there is considerable evidence for antibody-mediated immunity against both eye muscle (EM) and OCT antigens in TAO a role of cell-mediated immunity (CMI) has not been studied in detail. We have used a new sensitive test for CMI, the leukocyte procoagulant activity (LPCA) assay and tested blood leukocytes from patients with TAO and autoimmune thyroid disease (ATD) without evident ophthalmopathy for reactivity against pig eye muscle (PEM) and human thyroid and OCT membrane and soluble fractions. In some cases human EM fractions were also tested. Preparations of PEM membrane (PEMM) and human thyroid membrane induced a significant LPCA response in both groups of patients. PEM cytosol, human OCT membrane and cytosol and human spleen membrane did not evoke a significant response in either group of patients. There were significant positive correlations in patients with TAO between (i) LPCA in response to PEMM and that to human thyroid membrane and (ii) LPCA in response to human thyroid membrane and that to human EM membrane. In patients with TAO there were no significant associations between LPCA response to PEMM and the detection of serum antibodies to a 64 kDa EM membrane protein in immunoblotting, or between LPCA response to PEMM and the duration or severity of the ophthalmopathy or clinical evidence for eye muscle involvement. These findings confirm a role of cell-mediated immunity against eye muscle antigens in thyroid-associated ophthalmopathy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Urinary trypsin inhibitory activity for the diagnosis of bacterial infection: a prospective study in 690 patients.

OBJECTIVES: During the acute phase response, interleukin-1 induces production of inter-alpha-trypsin inhibitor. The measurement of urinary trypsin inhibitory activity which results from the effects of inter-alpha-trypsin inhibitor degradation products is easy, quick and inexpensive. We conducted a prospective study to investigate its value as a diagnostic tool in comparison with C-reactive protein. METHODS: Comparisons were made in 690 consecutive patients at admission to a department of internal medicine. RESULTS: The level of urinary trypsin inhibitory activity was significantly higher in patients with bacterial infection (mean = 123 IU/g creatinine) than in patients with either viral infection (34 IU), cancer (50 IU), elevated erythrocyte sedimentation rate without infection (45 IU), miscellaneous non-inflammatory diseases (27 IU) or in non-organic controls (19 IU) (Dunnet's test, p << 0.01). The receiver operating characteristic curve showed that sensitivity and specificity of urinary trypsin inhibitory activity were higher than those of C-Reactive protein for the diagnosis of bacterial infection. For levels > or = 60 IU, sensitivity was 75% and specificity 89%. Urinary trypsin inhibitory activity levels fell within 2 days in patients treated for acute bacterial infection. CONCLUSION: Urinary trypsin inhibitory activity could be a useful marker of bacterial infection particularly in patients with fever of unknown origin and/or elevated erythrocyte sedimentation rate.

Alpha-Globulins↗
PubMed1992

[The reproducibility of arrow-point registration in full-dentition subjects depending on the recording material].

The reproducibility of the intraoral central bearing point method was measured in 46 dentate subjects with a healthy stomatognathic system. Nine complete registrations were carried out on each volunteer, while three different materials were used for fixing the upper to the lower jaw. The occlusal records were examined in the condylar area on a specially designed articulator. Two therapists took part in this study. The shifts of the condylar spheres in all three spatial directions were found as follows: Ramitec 0.14 +/- 0.16 mm, Super-Bite 0.15 +/- 0.14 mm and Bite Compound 0.15 +/- 0.16 mm. The movements of the condylar spheres in space were calculated. They amounted to 0.28 +/- 0.23 mm when using Ramitec, 0.28 +/- 0.20 mm when using Super Bite and 0.31 +/- 0.23 mm when using Bite Compound. Statistically, the differences between the data of the three materials were not significant. Also, the results of our random sample were independent of the therapist.

Dental Articulators↗
PubMed1991

Cloning of the D-lactate dehydrogenase gene from Lactobacillus delbrueckii subsp. bulgaricus by complementation in Escherichia coli.

A strain of Escherichia coli (FMJ144) deficient for pyruvate formate lyase and lactate dehydrogenase (LDH) was complemented with a genomic DNA library from Lactobacillus delbrueckii subsp. bulgaricus. One positive cloned showed LDH activity and production of D(-)lactate was demonstrated. The nucleotide sequence of the D-LDH gene (ldhA) revealed the spontaneous insertion of an E. coli insertion sequence IS2 upstream of the gene coding region. The open reading frame encoded a 333-amino acid protein, showing no similarity with known L-LDH sequences but closely related to L. casei D-hydroxyisocaproate dehydrogenase (D-HicDH).

Amino Acid Sequence↗
PubMed1991

Pharmacokinetics of chlormezanone in elderly patients.

The pharmacokinetics of Chlormezanone (CM) has been determined after a single oral dose of 400 mg CM in 5 young volunteers (28 y) and in 8 elderly patients (79 y). In the young subjects, CM was rapidly absorbed and distributed, and was slowly eliminated with a half-life of 38 h major metabolites were not detected in plasma or urine. Only 3% of CM was excreted unchanged in urine. In elderly patients absorption was delayed but not reduced; the Cmax and AUC did not differ from those in younger subjects, the elimination rate was reduced compared to the younger subjects (mean 54 h). The increase was in part related to the reduction in renal function and metabolism observed in aging. However, the change in pharmacokinetics was moderate and no adjustment in dosage seems necessary for treatments of limited duration in elderly patients.

Administration, Oral↗
PubMed1991

Muscle and species reactivity of mouse monoclonal antibodies to human eye muscle membrane antigens.

We studied the tissue and species reactivity of mouse monoclonal antibodies (MCAB) produced by immunizing mice with a 100,000g ultracentrifuged preparation of human eye muscle (HEM) membranes. Twenty-three MCABs, 20 of which reacted in an enzyme-linked immunosorbent assay (ELISA) with HEM membrane, 2 with human thyroid membrane, and 1 nonreactive negative control, were selected for the study. The muscle and species specificity of 6 of the most reactive and more restrictively reactive MCAB were studied in more detail. All reacted in ELISA with human skeletal muscle membrane and, to a lesser extent, with human cardiac muscle membrane, but not with human brain membrane. The 6 MCAB cross-reacted with eye muscle membrane prepared from pig but not rat, although reactivity with human tissue was greatest for all MCAB tested. When tested in immunoblotting with HEM and thyroid membranes, 3 of 6 MCAB reacted with a 64-kDa protein in HEM, 2 of which also reacted with an antigen of the same molecular weight in thyroid membrane. In a complement-mediated antibody-dependent cytotoxicity assay, 5 of 19 MCAB lysed HEM cells, 6 of 21 lysed human skeletal muscle cells, and 10 of 22 lysed human thyroid cells. These findings support results from earlier clinical studies which showed that eye muscle membrane reactive autoantibodies in the serum of patients with thyroid-associated ophthalmopathy cross-react with membrane prepared from other striated muscle. The significance of eye muscle, skeletal muscle, and thyroid cross-reactivity of MCAB is discussed in the context of autoimmune thyroid disease and ophthalmopathy.

Abdominal Muscles↗
PubMed1991

Prevalence of antibodies reactive with a 64 kDa eye muscle membrane antigen in thyroid-associated ophthalmopathy.

We have determined the prevalences of antibodies reactive with certain pig eye muscle membrane antigens, as determined from SDS-polyacrylamide gel electrophoresis (PAGE) and western blotting, in patients with autoimmune thyroid disorders with or without associated ophthalmopathy. The most frequently detected antibody was that directed against a protein of 64 kDa. Antibodies against this antigen were detected in 33% of unselected patients with ophthalmopathy and in 75% of those with severe, active, orbital inflammation of less than 12 months duration. Such antibodies were detected also in 33% of patients with Graves' hyperthyroidism with no apparent eye disease and in 17% of patients with Hashimoto's thyroiditis with no eye disease but were not detected in patients with nonautoimmune thyroid disorders in 25 normal subjects tested. In the majority of sera showing reactivity with this protein, reactivity with membrane antigens of 55 and 95 kDa also were observed, suggesting that the three proteins were conformationally associated. Cytotoxic antibodies against human eye muscle cells, measured in antibody-dependent cell-mediated cytotoxicity (ADCC), were demonstrated in 37% of patients with ophthalmopathy. There was no significant correlation, in patients with eye disease, between positive ADCC tests and antibodies to the 64 kDa protein, the 64 kDa reactive antibody being found in 50% of patients with positive ADCC and in 35% of those with negative tests. In this study, a clear association has been shown between thyroid-associated ophthalmopathy and the detection, in immunoblotting, of antibodies reactive with a 64 kDa eye muscle membrane antigen.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

The effect of infinitesimal drug dilutions on the pharmacokinetics of nalidixic acid and atenolol.

1. Ten healthy subjects received two treatments: a single 1 g oral dose of nalidixic acid (NA) followed 1 h later by either an infinitesimal dilution of the drug (NA 7CH) or by succussed water which served as placebo. The study was repeated 18 months later in 10 different subjects. 2. A further 10 healthy subjects received three treatments: a single 100 mg oral dose of atenolol (AT) followed 3 h later by either placebo or a dilution of AT (AT 7CH) or of bisoprolol (BI 7CH). The homoeopathic preparations were administered by the sublingual route. 3. In the first NA experiment NA 7CH significantly shortened the elimination half-life of NA from 8.6 +/- 2.2 (placebo) to 6.4 +/- 1.6 h (NA 7CH). In the second NA experiment none of the pharmacokinetic parameters was modified significantly by the administration of NA 7CH. Neither AT 7CH nor BI 7CH modified the pharmacokinetics of AT.

Administration, Oral↗
PubMed1991

Binding of peripheral blood and thyroidal T lymphocytes to thyroid cell monolayers: possible role of "homing-like" receptors in the pathogenesis of thyroid autoimmunity.

The specific binding of blood lymphocyte populations to non-antigenic receptors on high endothelial cells in peripheral lymphoid organs is well established. Such "homing" receptors in target tissues may also play a role in the early phase of organ specific autoimmunity. In this study binding of peripheral blood and thyroid-derived T cells to human thyroid (THY) cells was examined. Binding was measured as the percentage 51Cr-labelled T cells bound to THY monolayers. Interferon-gamma (IFN-gamma) enhanced the binding of peripheral blood T cells (PBL-T) from patients with Graves' disease (GD) and normals, but not from patients with Hashimoto's thyroiditis (HT), to allogeneic THY monolayers. The binding of T cells from patients with HT to untreated allogeneic THY monolayers was significantly greater than that for T cells from patients with GD or normals. TSH inhibited the IFN-gamma enhancement of binding of PBL-T from 4 normals and one HT patient to both allogeneic (n = 5) and autologous (n = 4) THY monolayers. Intra-thyroid T cells (ITL-T) bound to autologous THY monolayers significantly more than PBL-T from the same patient, while ITL from patients with HT or Graves' disease bound more than their PBL-T to both allogeneic and autologous THY monolayers. ITL-T, but not PBL-T, bound significantly more to autologous THY than to autologous thyroid-derived fibroblast monolayers.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

[The reproducibility of the abutment angle recording in the remounting of complete dentures].

Upon insertion, 40 newly made full dentures could be remounted three times in succession by each of two therapists by means of the intraoral central bearing point method. The records were measured electronically and by computer in a special measuring articulator in the right and left condylar area. The shift of the condylar spheres in the three different records was smaller than about 0.3 +/- 0.2 mm in all three spatial directions. From this we calculated the movement of the spheres in space to be about 0.5 +/- 0.3 mm. The results of our random samples were independent of the therapist, the patients' age or sex, the period for which the patients had been edentulous, the sliding of the dental prostheses on the tegmentum or the anatomical shape of the alveolar ridges.

Dental Abutments↗
PubMed1990

Predictive value of phase I studies: relevant criteria.

Phase I studies cannot predict the therapeutic efficacy of a new drug. However, they can lead to important information concerning: i), the undersirable effects and their mechanisms of occurrence; and ii), the pharmacokinetics and the metabolism of the drug as well as their possible alterations in renal or hepatic diseases. When considering the therapeutic effects, 3 cases have to be considered which are, in order of decreasing predictive value: i), when a direct relationship is expected between the drug concentration in the body and its therapeutic effects (eg, antibiotics); ii), when the drug has a known molecular or cellular target which is directly involved in the pathophysiology of the disease (eg, renin inhibitors); and iii), when the drug does not have a known target or is directed toward a precise target which is not directly involved in the disease. In all these cases, a phase I study in healthy volunteers should be able to describe, at least qualitatively, the pharmacodynamic effects of the drug which are relevant to its therapeutic goal.

Drug Evaluation↗
PubMed1990

Eye muscle membrane reactive antibodies are not detected in the serum or immunoglobulin fraction of patients with thyroid-associated ophthalmopathy using an ELISA and crude membranes.

We tested sera and purified immunoglobulin (Ig) fractions from patients with autoimmune thyroid disorders (AITD), with and without ophthalmopathy, and normal subjects, for the presence of antibodies reactive with eye muscle membrane antigens in an optimized enzyme-linked immunosorbent assay (ELISA). We found no correlation between ELISA results and the presence or severity of ophthalmopathy in patients with AITD for either serum or Ig, and there were no significant differences between the mean values (+/- SE) for the three groups (AITD with ophthalmopathy, AITD without ophthalmopathy and normals) for either serum or Ig. In contrast Ig from 8 of 19 (45%) patients with thyroid-associated ophthalmopathy reacted with a 64 kDa eye muscle membrane antigen in SDS-polyacrylamide gel electrophoresis and Western blotting, while tests were positive in only one of the 8 patients with AITD without eye disease and in none of the 8 normal subjects. The presence of antibodies to a 64 kDa antigen in immunoblotting did not correlate with the levels of antibodies measured in ELISA. We conclude that the ELISA, incorporating a crude membrane fractions as antigen, is not useful as a clinical test for eye muscle autoantibodies.

Adult↗
PubMed1989

The influence of renal insufficiency and haemodialysis on the kinetics of ciprofibrate.

1. The kinetics of the hypolipidaemic drug, ciprofibrate, were studied after a single oral dose (100 mg) in subjects with normal renal function (n = 6), patients with mild (n = 6) and severe (n = 6) renal insufficiency as well as in haemodialysed patients (n = 5). 2. Under fasting conditions, ciprofibrate, was absorbed rapidly in subjects with normal renal function, and its apparent elimination half-life was approximately 81 h. Both renal clearance (0.15 ml min-1) and cumulative renal excretion (less than 7% of the administered dose) were low. 3. Mild renal insufficiency did not alter the pharmacokinetics of ciprofibrate, but severe renal impairment significantly reduced both its renal clearance and cumulative urinary excretion and increased the apparent elimination half-life. 4. A 5 h haemodialysis session did not lower the plasma concentrations of ciprofibrate. 5. It is concluded that, from a pharmacokinetic point of view, a reduction in the dosage of ciprofibrate should be considered in patients with a glomerular filtration rate below 30 ml min-1/1.73 m2.

Adult↗
PubMed1989

[Collagen colitis. Reflections apropos of 40 patients].

The aim of this study was to evaluate the frequency of a thickened subepithelial collagen band in the colon, its relationship to diarrhea, and the clinical relevance of its detection. During a 3.5 year period (May 1985-January 1989), a total of 3,323 biopsy specimens were obtained during 6,254 colonoscopies. A subepithelial collagen thickening greater than 10 microns was found in 40 patients (1.5 percent of the patients). Further assessment of these 40 patients showed that this histological lesion was characterized by a frequent association with chronic diarrhea (in 36 patients, i.e. 90 percent) whatever the cause, with diseases such as diabetes mellitus (8 cases) or inflammatory arthropathies (6 cases) and with a microscopic colitis in all cases. Course of collagen thickening was variable and independent of clinical course. Diarrhea was a constant finding when the collagen thickening was greater than 15 microns and frequently improved (12 patients/14) during treatment with Collagenan. This study suggests that a subepithelial thickened collagen band is an uncommon change in the colon and is frequently associated with chronic diarrhea. The significance of this morphological change is unknown, and its contribution to the pathogenesis of the diarrhea remains questionable.

Chronic Disease↗