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J H Lazarus

Publications and source records attributed to J H Lazarus.

At least 19 recordsLinked to original sources

Association between postpartum thyroid dysfunction and thyroid antibodies and depression.

OBJECTIVE: To define the relation between mood and autoimmune thyroid dysfunction during the eight months after delivery. DESIGN: Double blind comparison of the psychiatric status of women positive and negative for thyroid antibodies. Clinical examination and blood sampling for free triiodothyronine and thyroxine, thyroid stimulating hormone, and thyroid antibody concentrations at four weekly intervals. Psychiatric assessment at six, eight, 12, 20, and 28 weeks post partum. SETTING: Outpatient department of district hospital. PATIENTS: 145 antibody positive women and 229 antibody negative women delivering between August 1987 and December 1989. MAIN OUTCOME MEASURES: Thyroid status. Number of cases of mental ill health by the general health questionnaire, research diagnostic criteria, Hamilton 17 item depression scale, hospital anxiety and depression scale, and Edinburgh postnatal depression scale. RESULTS: Six weeks after delivery the general health questionnaire showed 62 (43%) antibody positive women and 65 (28%) antibody negative women had mental ill health (chi 2 = 8.18, p less than 0.005). Follow up of 110 antibody positive and 132 antibody negative women showed significantly greater depression by research diagnostic criteria in antibody positive women (47%) than antibody negative women (32%) regardless of thyroid dysfunction. Antibody positive women showed higher mean scores for depression on the Hamilton (6.01 v 3.89, p = 0.0002), Edinburgh (7.45 v 5.92, p = 0.031), and hospital depression scales (4.95 v 3.79, p = 0.003). CONCLUSION: Depressive symptoms are associated with positive thyroid antibody status in the postpartum period.

Autoantibodies

The sonographic appearances in postpartum thyroiditis.

During the postpartum period about 50% of women with circulating thyroid autoantibodies develop a transient autoimmune thyroiditis. To determine the sonographic appearances in postpartum thyroiditis (PPT), serial ultrasound (US) scans of the thyroid were performed in 135 postpartum women who were divided into three clinical groups: Group 1, 37 antibody positive subjects who developed PPT; Group 2, 28 antibody positive subjects in whom thyroid function remained normal; Group 3, 70 antibody negative controls. Thyroid hypoechogenicity was observed in 14/31 patients (45%) who were scanned between 4 and 8 weeks postpartum and who subsequently developed PPT (Group 1) compared with 4/24 patients (17%) in Group 2 (P less than 0.05) and 1/65 patients (1.5%) in Group 3 (P less than 0.001). In antibody positive patients, the positive predictive value of an abnormal scan during this period was 78%. Between 15 and 25 weeks postpartum thyroid hypoechogenicity was present in 32/37 patients (86%) in Group 1 compared with 11/28 patients (39%) in Group 2 (P less than 0.001) and 2/70 patients (3%) in Group 3 (P less than 0.001). Sonographic abnormality persisted beyond 32 weeks postpartum in 36/41 antibody positive patients (87%) who had exhibited thyroid hypoechogenicity earlier during the study and who had late scans. The characteristic US appearance in PPT is thyroid hypoechogenicity. The role of sonography in the prediction, diagnosis and follow up of patients with PPT is discussed.

Autoantibodies

Iodine metabolism in postpartum thyroiditis.

To investigate the etiologic role of iodine intake in postpartum thyroiditis (PPT), we have measured postpartum urinary iodine excretion serially in a large prospective study of PPT. A total of 1996 women were screened for thyroid microsomal antibody during the second trimester of pregnancy. One hundred fifty-two of the 235 antibody-positive women and an equal number of age-matched antibody-negative controls were followed postpartum with measurements of urinary iodine and thyroid function at monthly intervals for 12 months. Iodine excretion in the immediate postpartum period did not differ between the 73 women who developed PPT and the antibody-negative controls. In women with PPT with hyperthyroidism, hypothyroidism, or hyperthyroidism followed by hypothyroidism, increased urinary iodine excretion was observed between 8 and 16 weeks postpartum, which preceded the hormonal disturbances among the women with hypothyroidism. The height of the rise in urinary iodine excretion during the first 20 weeks postpartum correlated with the serum free thyroxine levels (r = 0.61, p less than 0.001). Iodine intake is unlikely to affect the prevalence of PPT. However, these data show that the hyperthyroid phase of PPT is associated with a significant release of intrathyroidal iodine due to thyroid destruction and that the same process also occurs to a lesser extent before the hormonal disturbances associated with hypothyroid PPT.

Autoantibodies

Reversible adrenocorticotropin deficiency due to probable autoimmune hypophysitis in a woman with postpartum thyroiditis.

The natural history and pathogenesis of lymphocytic hypophysitis remain poorly understood. We describe a 34-yr-old woman with postpartum thyroiditis and ACTH deficiency, studied at monthly intervals for 18 months after pregnancy. A significant titer of thyroid peroxidase autoantibodies was detected at 16 weeks gestation, and she was recruited into a prospective study of postpartum thyroid function. Four months postpartum she developed mild hyperthyroidism [free T4 (fT4), 27 pmol/L; TSH, less than 0.2 mU/L] and showed a rise in thyroid peroxidase and thyroglobulin autoantibodies. At 9 months postpartum, serum fT4 and fT3 levels were low normal (8.0 and 1.7 pmol/L, respectively), but TSH was not raised (0.4 mU/L). Subsequent investigation showed a low basal plasma cortisol level (28 nmol/L) in association with undetectable ACTH, and subnormal cortisol responses to depot Synacthen (535 nmol/L at 6 h) and hypoglycemia (peak, 145 nmol/L). FSH, LH, GH, and PRL function and computerized tomography of the pituitary were normal. Retrospective analysis of serum samples taken throughout the postpartum year showed developing hypocortisolemia between 3-9 months postpartum. Each sample was also tested for pituitary autoantibodies using a specific indirect immunofluorescent assay; none was detected. The ACTH deficiency recovered spontaneously, with normal cortisol responses to depot Synacthen (greater than 1380 at 6 h) and hypoglycemia (peak, 590) 14 and 18 months postpartum, respectively. This case illustrates that postpartum pituitary deficiencies are potentially reversible. The pattern of pituitary deficit and postpartum thyroiditis supported a diagnosis of autoimmune hypophysitis.

Adrenocorticotropic Hormone

Endemic goitre in Senegal--thyroid function etiological factors and treatment with oral iodized oil.

Endemic goitre and its response to orally administered iodized oil has been studied in seven villages 25-30 km south of Velingara, Eastern Casamance, Senegal. In 502 adults aged greater than 15 years goitre prevalence was 62% with 18.2% having goitre grade 2 or 3. Mean free T4 (FT4) was 11.9 +/- 3.5 (SD) pmol/l and iodine deficiency was confirmed by noting median urinary I of 0.079 mumol/l (14.9 mumol I/mol creatinine) with elevated free T3 (FT3)/FT4 ratios. Serum selenium concentrations were normal. The response to 480 mg of oral iodized oil assessed at 6 and 12 months was characterized by a 35.8% increase in FT4, a 25% decrease in FT3 and a 50% decrease in TSH (all p less than 0.01) at 12 months associated with a significant decrease in goitre size measured in 70 persons when compared to 65 controls not receiving iodine. Urinary iodine rose from 0.071 mumol/l to 0.189 mumol/l (p less than 0.01) during this time and no adverse effects on thyroid antibodies (anti-thyroid peroxidase and anti-thyroglobulin) were observed. A variation in goitre prevalence between villages was noted which, in such a small geographical area, suggests that etiological factors in addition to iodine deficiency may be important in goitre pathogenesis. Oral iodized oil administration is an effective treatment for iodine deficiency goitre in the short term.

Adolescent

Postpartum thyroiditis: an organ specific syndrome which is not associated with a postpartum polyclonal B-cell activation.

Recent reports have detailed the presence of autoantibodies characteristic of non-organ specific autoimmune diseases in the serum of patients with autoimmune postpartum thyroiditis (PPT). These observations suggest that PPT could be part of a polyclonal B-cell activation postpartum. We have measured 4 non-organ specific autoantibodies (anti-DNA, anti-cardiolipin, anti-nuclear factor (ANF) and antibodies against extractable nuclear antigens (ENA)) together with autoantibodies against thyroglobulin and thyroid peroxidase in a group of PPT women at 4 time points during the first year postpartum (early, time of hyperthyroidism, time of hypothyroidism, late). Whilst 18/18 patients showed thyroid specific autoantibody changes there was only a low frequency of occurrence of the non-organ specific autoantibodies (ENA 2/18; ANF 1/18; anti-DNA 2/18; anti-dsDNA 0/18; anti-cardiolipin 0/18) and, when positive, the response was poor. We conclude that PPT is not associated with a polyclonal b-cell activation but is a postpartum rebound of a thyroid specific autoimmune phenomenon.

Antibodies, Antinuclear

The measurement of complement fixation by autoantibodies directed against thyroid membrane antigens.

This paper describes the use of sensitized sheep red blood cells for the detection and titration of complement fixation by autoantibodies directed against human thyroid membranes in the serum of patients with autoimmune thyroid disease. Patients with elevated circulating levels of TPO antibodies and diagnosed as having autoimmune hypothyroidism (including Hashimoto's disease) or autoimmune hyperthyroidism (Graves' disease) were studied. Complement fixation titres were highest in those patients with autoimmune hypothyroidism compared with the autoimmune hyperthyroid group. Serum samples obtained from a group of patients with thyroid neoplasia and from normal healthy volunteers were negative in this test. The TPO antibody activity when "corrected" for its CF potency suggests that the autoantibodies found in autoimmune hypothyroidism are potentially more destructive than those found in the non-destructive autoimmune thyroid diseases.

Analysis of Variance

Elisa for the measurement of complement C3 activation by autoantibodies directed against thyroid membrane antigens.

This paper describes the use of an ELISA technique to assess the involvement of the complement system in the pathogenesis of autoimmune thyroid disease (AITD). Microtitre plates coated with thyroid membrane antigen were exposed to serum samples obtained from AITD patients, all of whom showed elevated levels of circulating anti-thyroid autoantibodies, and dilute guinea pig serum, as a source of complement, was then added to the microtitre wells. The degree of activation of the classical complement pathway was assessed by measuring the bound complement component C3 using a peroxidase conjugated anti-guinea pig C3 antiserum. C3 fixation and activation was greater in the presence of serum from patients with Hashimoto's disease when compared with that seen in patients with autoimmune hyperthyroidism (Graves' disease). Serum samples obtained from normal healthy volunteers and from patients with thyroid neoplasia were negative in this assay. The method allows the calculation of a putative "biologically active autoantibody" level and analysis of these data confirm our earlier observation that the species of autoantibody found in autoimmune hypothyroidism are potentially more destructive than those found in other forms of AITD.

Animals

Interference in thyroid-function tests in postpartum thyroiditis.

Three women are described from a study of patients with postpartum thyroiditis whose sera gave spuriously increased concentrations of free thyroid hormone because of antibody binding of radiolabeled thyroxin (T4) and triiodothyronine (T3) analogs. All of the women showed increased serum concentrations of thyroid autoantibodies. The antibody binding of radiolabeled analogs and its effect on free T4 and free T3 assays disappeared by 48 weeks postpartum. Postpartum women who develop thyroid autoantibodies have approximately 2% prevalence of increased binding of radiolabeled analogs, which can result in an interference in thyroid hormone assays involving T4 and T3 analogs.

Autoantibodies

Mitochondrial thyroid hormone receptor: localization and physiological significance.

Binding studies of thyroid hormone to submitochondrial fractions from rat liver suggest that the component responsible for high-affinity, low-capacity (saturable) binding of hormones arises from the inner mitochondrial membrane. The partially purified component, approximately 150,000 daltons, appears to be half protein and half lipid, largely phospholipids, tentatively identified as lecithin, phosphatidyl ethanolamine, and cardiolipin. A similar hormone-binding macromolecule was found in mitochondria from rabbit kidney, from human liver and kidney, and from rat kidney, myocardium, skeletal muscle, intestinal mucosa, whole small intestine, adipose tissue, and lung. It was absent from mitochondria of adult rat brain, spleen, and testis, organs calorigenically unresponsive to thyroid hormones injected in vivo, but was present in mitochondria from brains of rats 12 days old and younger. The organ distribution of the hormone-binding protein and its presence in neonatal brain mitochondria supports the biological relevance of the mitochondrial component as a thyroid hormone receptor.

Animals

The effect of lithium on the iodide concentrating mechanism in mouse salivary gland.

The iodide concentrating mechanism, measured as the gland to plasma (G/P) 125I- concentration ratio, was measured in male mouse submandibular glands after the animals had been fed with varying amounts of lithium chloride for intervals ranging from 0 to 8 weeks. After acute exposure (by injection) to lithium the G/P 125I- fell compared to control values and was further depressed at high serum lithium values. Chronic exposure to lithium was characterised by an increase in the G/P 125I- ratios at therapeutic serum lithium concentrations. It is suggested that lithium has a direct effect on the iodide concentrating mechanism that may be independent of any action of thyroid stimulating hormone during this process. The effect may be important in the formation of lithium induced goitre.

Animals

Partial purification of thyroid hormone receptor from mitochondrial inner membrane: evidence for a physiologic role.

Recently we described a protein component, from the inner mitochondrial membrane, which binds thyroid hormone with high affinity, low capacity (saturable) characteristics. This partially purified rat liver mitochondrial membrane component appears to be a 150,000 daltons lipoprotein complex. Phospholipids, tentatively identified as lecithin, phosphatidyl ethanoamine, and cardiolipin, appear to constitute 50% of this complex. A similar hormone binding marcomolecule was also found in mitochondria from rabbit kidney, as well as human liver and kidney. In the rat this saturable thyroid hormone binding component was found in mitochondria from liver, kidney, myocardium, skeletal muscle, intestinal mucosa, whole small intestine, adipose tissue, and lung. It was absent from the mitochondria of adult brain, spleen and testis, organs known to be calorigenically unresponsive to thyroid hormones injected in vivo. In contrast, neonatal rat brains contain the protein with binding constants similar to those of neonatal or adult rat liver mitochondria, but in older rat brains (14 and 17 days) the saturable binding was no longer present, as in adult brain. These data provide strong support for the biological relevance of the mitochondrial component as a thyroid hormone receptor.

Animals

Thyroid hormone action: the mitochondrial pathway.

The subcellular compartments have been investigated to compare proteins capable of binding triiodothyronine and thyroxine; specific binders have been found in cytosol, nuclei, and mitochondria from rat liver and kidney. The binding protein from the inner mitochondrial membrane had the highest association constant (greater than 10(11) liters per mole), suggesting possible direct hormone action on the mitochondria. Binding of hormone analogs was found to be related to known physiological potency, and stereospecific discrimination between L- and D-thyroxine was observed. The saturable receptor was found in the mitochondrial membranes of rat liver, kidney, myocardium, and skeletal muscle but not in mitochondria from the unresponsive tissues: brain, spleen, and testis. Oxidative phosphorylation by mitochondrial vesicles from hypothyroid rats increased after the addition of physiological concentrations of triiodothyronine, which corroborated direct hormone action on mitochondria.

Animals

The final examination in United Kingdom medical schools, 1974.

The structure, character and results of the final M.B. examinations held in United Kingdom medical schools in 1974 were investigated by postal questionnaire. The mean failure rate (10-5%, range 0-24-6%) was significantly higher in the student sample from the London medical schools compared with those in the periphery. No significant sex difference in total failure rate was noted. Wide variations were observed in the length and character of the examinations.

Education, Medical, Undergraduate