HLA-DR antigen expression on intrathyroidal lymphocytes and thyrocytes in Hashimoto's thyroiditis and Graves' disease: an immunohistological study

In frozen sections of thyroid glands with Hashimoto's thyroiditis (HT) and Graves' disease (GD), infiltrating lymphocytes were tested for their expression of HLA-DR antigens as a marker of in situ activation. In a combination of indirect immunoperoxidase and direct immunofluorescence staining, most of the immunoglobulin D positive mature B cells were found to be DR positive (DR+) in both diseases. In HT, sizable portions of both helper/inducer T (Leu3+) and suppressor/cytotoxic T (Leu2+) cells were DR+ in interfollicular regions as well as in lymphocyte clusters and lymphoid follicles. In GD, the proportion of DR+ cells in the interfollicular Leu2+ population was significantly lower than that of HT. DR+ thyrocytes were seen in all 14 cases of HT and in 14 out of 16 cases of GD, especially in the vicinity of lymphocyte aggregates. The extent of their DR expression was not correlated with the percentage of DR+ cells in either T subset. These results indicate that a significant portion of infiltrating T cells are activated in autoimmune thyroid diseases, and there may be bidirectional interaction between DR+ thyrocytes and DR+ T cells. The difference in frequency of Leu2+ DR+ cells may account for the difference between the immunopathological features of HT and GD.

Ovarian cystic teratomas: MR imaging

Magnetic resonance (MR) imaging characteristics of ovarian cystic teratomas were evaluated in 18 patients with 23 surgically proved tumors. The fat within the tumor demonstrated characteristic intensity similar to that of subcutaneous fat and a pathognomic pattern of chemical shift artifact that helped differentiate ovarian cystic teratomas from endometrial cysts. In addition to fat, MR images of ovarian cystic teratomas had several other characteristics that allowed confident diagnosis, including gravity-dependent layering or floating debris, palm tree-like protrusions or rounded nodules (dermoid plugs), and, occasionally fat-fluid levels and globular calcification. MR images were diagnostic in 20 tumors and were able to depict a tumor measuring 2 cm in diameter. MR imaging appears to be valuable in problematic cases in which other modalities are not diagnostic.

Direct radiographic magnification with computed radiography

Computed radiography was combined with a 0.1-mm microfocus radiographic tube to obtain radiographic magnification of a x3 to x5. Gray-scale image processing compensated for the loss of radiographic contrast associated with the high-kilovoltage, short-exposure technique. The high-pass spatial frequency filtering capability of the computed radiography resulted in enhanced edges and increased displayed latitude. The improved image quality obtained by magnification computed radiography allowed delineation of subtle abnormalities and small anatomic structures not apparent on conventional screen-film contact or magnification radiographs.

Vaginal agenesis: classification by MR imaging

Vaginal agenesis was studied by magnetic resonance (MR) imaging lin a 15-year-old girl, a 19-year-old woman, and a 21-year-old woman. In each case MR studies demonstrated the presence or absence of a normal cervix and functioning endometrium. This information was useful in planning surgical management. MR imaging assisted in the classification of the abnormality by noninvasively demonstrating the details of pelvic anatomy-and the uterine morphologic characteristics.

Anterior and posterior lobes of the pituitary gland: assessment by 1.5 T MR imaging

Pituitary glands of 60 normal volunteers (30 men 20-36 years old, and 30 women 18-42 years old) were studied by 1.5 T magnetic resonance (MR) imaging. The T1-weighted images (T1WI) [repetition time (TR) = 400 ms; echo time (TE) = 25 ms] were obtained in the coronal, sagittal, and axial planes. Proton density (PD)/T2-weighted images (PDWI/T2WI) (TR = 2,000 ms; TE = 25/100 ms) were obtained in the sagittal plane using 3 mm slice thickness. On T1WIs of all subjects the posterior part (PP) of the pituitary fossa showed the highest signal, which was indistinguishable from fatty tissue. This study reveals that this region of high signal intensity (PP) corresponds to the posterior lobe and not intrasellar fat because its shape, size, and position are compatible with the posterior lobe; its signal intensity differs from that of fatty tissue on PDWI and T2WI; the absence of an intrinsic chemical shift artifact (CSA) characteristic of fat; and due to CSA, a dorsum with fatty marrow is shifted relative to the PP (or may be made to merge with it). Regarding the differentiation of the two lobes of the pituitary gland on MR, the morphology of the anterior and posterior lobes was evaluated and great variation found. Appreciation of normal is particularly important in evaluating coronal images for small pituitary lesions.

Optimization and clinical assessment of a radioreceptor assay for thyrotropin-binding inhibitor immunoglobulins

We tried to improve the sensitivity of a radioreceptor assay for thyrotropin-binding inhibitor immunoglobulins (TBII) by modifying assay conditions. About a twofold increase in sensitivity without a loss of reproducibility was obtained by prolonging the incubation of the receptors with test serum from 15 to 120 min before the addition of 125I-labeled thyrotropin. In 20 untreated, 49 treated patients with Graves' disease and 19 patients with euthyroid Graves' disease, TBII activities obtained using 120 min preincubation were significantly higher than those obtained using 15 min preincubation (p less than 0.005). No significant increase in TBII activities was observed in the presence of sera from patients with primary hypothyroidism (n = 17), simple goiter (n = 7), adenomatous goiter (n = 11), thyroid adenoma (n = 11) or cancer (n = 12). TBII were detectable in 15 (47%) of 32 triiodothyronine-nonsuppressible Graves' patients who were receiving maintenance antithyroid drug therapy using 120 min preincubation, while they were positive in only 6 patients (19%) using 15 min preincubation. The assay using a longer preincubation period was found to be sensitive, specific and useful for diagnosis and follow-up of Graves' disease.

Endometrial cysts of the ovary: MR imaging

Magnetic resonance (MR) images of 15 cases of ovarian endometrial cyst were reviewed. With a high-field-strength (1.5-T) MR imager, T1- and T2-weighted images were obtained in axial and sagittal planes, with 5-mm section thickness. MR findings highly suggestive of an endometrial cyst included adhesions to the surrounding organs (e.g., loss of clear margin of the uterine body and tethered appearance of the rectum); a distinct low-intensity zone surrounding a cyst loculus on both T1- and T2-weighted images produced by a thick fibrous capsule; loculus contents with short T1 and long T2 values, attributed to hemorrhagic fluid; and prominent low intensity (shading) within a loculus on T2-weighted images, the mechanism of which is yet to be determined.

Pontine ataxic hemiparesis studied by a high-resolution magnetic resonance imaging system

Using a high-resolution magnetic resonance imaging system, we studied 3 patients who had exhibited pontine ataxic hemiparesis. In each patient, the ischemic lesions responsible for the contralateral ataxia were located in the dorsomedial basis pontis. The isointensity bands in the ischemic area on T2-weighted images showed the spared transverse fibers originating from the contralateral pontine nuclei, and this may explain the cause of the unilateral ataxia.

Carbachol regulates cholecystokinin receptor on pancreatic acinar cells

We have examined the effect of carbamylcholine on the binding of cholecystokinin (CCK) to dispersed acini from rat pancreas. The CCK receptor on pancreatic acini possesses two classes of binding sites. Simultaneous addition of carbamylcholine inhibited binding of CCK to acini due to an apparent loss of high affinity CCK binding sites. Atropine prevented the inhibitory effect of carbamylcholine, whereas calcium ionophore A23187 did not alter binding of CCK. 12-O-tetradecanoylphorbol-13-acetate (TPA) inhibited binding of CCK in the same manner as carbamylcholine. Inhibition by carbamylcholine was reversible and the recovery was time dependent. By contrast, inhibition of binding of CCK by TPA did not reverse after a 60-min incubation without the agent. These findings, at least in part, account for the inhibition of the CCK-induced stimulation of amylase secretion by carbamylcholine. The action of TPA on binding of CCK suggests the possible involvement of the activation of protein kinase C in the inhibition of binding.

Inhibition of thyrotropin-induced growth of rat thyroid cells, FRTL-5, by immunoglobulin G from patients with primary myxedema

We studied thyroid growth-blocking activity in immunoglobulin G (IgG) fractions of serum from 24 patients with primary myxedema, 24 patients with goitrous Hashimoto's thyroiditis, and 18 normal subjects by measuring the ability of their IgG to inhibit TSH-induced [3H]thymidine incorporation into DNA in a rat thyroid cell line, FRTL-5. Both groups of patients were receiving T4 when studied. [3H]Thymidine incorporation induced by 0.1 mU/ml bovine TSH was significantly inhibited by the addition of 2 mg/ml IgG from patients with primary myxedema (P less than 0.01), while it was not affected by IgG from the normal subjects or 23 of the 24 patients with goitrous Hashimoto's thyroiditis. IgG from patients with primary myxedema also inhibited the [3H]thymidine incorporation induced by Graves' IgG, but not that induced by forskolin, cholera toxin, (Bu)2cAMP or phorbol-12-myristate-13-acetate. The inhibition of TSH-induced [3H]thymidine incorporation by IgGs from patients with primary myxedema was significantly correlated with their inhibitory activities against both TSH-induced cAMP generation and TSH binding (P less than 0.001). These data indicate that these growth-blocking antibodies are directed against the TSH receptor and might be one of the causes of the thyroid atrophy in patients with primary myxedema.

Autoantibody against diiodinated tyrosine-gastrin in a patient with Graves' disease

We describe autoantibodies against iodinated gastrin in a patient with Graves' disease. Values for serum gastrin differed in this case, depending on which of two different radioimmunoassay (RIA) kits was used. RIA with the dextran-coated charcoal method for separation of free tracer gastrin gave a value less than 9.5 pmol/L, whereas the value by a RIA kit by the double-antibody method was 318 pmol/L. The patient's serum contained a binding protein for 125I-labeled gastrin, as detected by Sephadex G-200 column chromatography. The IgG fraction was responsible for the ability of serum to bind 125I-labeled gastrin. Interestingly, of the two possible forms of iodinated gastrins, monoiodinated (MIT) and diiodinated (DIT) tyrosine-125I-labeled gastrin, only the latter bound to patient's IgG. Furthermore, DIT-gastrin, but not gastrin or MIT-gastrin, inhibited the binding of DIT-125I-labeled gastrin. The patient's serum evidently contains autoantibodies against DIT-gastrin that interfere with RIA of gastrin.

Circulating 1,25-dihydroxyvitamin D concentrations in patients with renal cell carcinoma-associated hypercalcemia are rarely suppressed

We measured serum 1,25-dihydroxyvitamin D concentrations in 18 patients with renal cell carcinoma-associated hypercalcemia. Only 2 patients (11%) had low serum 1,25-dihydroxyvitamin D (less than 15 pg/ml) levels, and the mean 1,25-dihydroxyvitamin D level in the 18 patients was 44 +/- 30 (+/- SD) pg/ml, not different from the value of 42 +/- 22 pg/ml in 75 age-matched normocalcemic patients with various malignancies. Eighty-seven percent (26 of 30) of the hypercalcemic patients with extensive skeletal metastases due to other malignancies or with hematological malignancies had suppressed serum 1,25-dihydroxyvitamin D levels (less than 15 pg/ml). In hypercalcemic patients with other malignancies and no skeletal metastases, only 54% (21 of 39) had low serum 1,25-dihydroxyvitamin D levels. The mean serum 1,25-dihydroxyvitamin D level in the latter group was 21 +/- 26 pg/ml, significantly lower than that in normocalcemic patients. In renal cell carcinoma-associated hypercalcemia, suppression of circulating 1,25-dihydroxyvitamin D concentrations is uncommon.

Magnetic resonance images of neuro-Behçet syndrome show precise brain stem lesions. Report of a case

Neuro-Behçet syndrome was investigated with magnetic resonance imaging (MRI) showing precise images of brain stem lesions, and therefore suggesting the clinical usefulness of MRI in diagnosis of neuro-Behçet syndrome.

Autoantibody against diiodinated tyrosine-gastrin in a patient with Graves' disease

We describe autoantibodies against iodinated gastrin in a patient with Graves' disease. Values for serum gastrin differed in this case, depending on which of two different radioimmunoassay (RIA) kits was used. RIA with the dextran-coated charcoal method for separation of free tracer gastrin gave a value less than 9.5 pmol/L, whereas the value by a RIA kit by the double-antibody method was 318 pmol/L. The patient's serum contained a binding protein for 125I-labeled gastrin, as detected by Sephadex G-200 column chromatography. The IgG fraction was responsible for the ability of serum to bind 125I-labeled gastrin. Interestingly, of the two possible forms of iodinated gastrins, monoiodinated (MIT) and diiodinated (DIT) tyrosine-125I-labeled gastrin, only the latter bound to patient's IgG. Furthermore, DIT-gastrin, but not gastrin or MIT-gastrin, inhibited the binding of DIT-125I-labeled gastrin. The patient's serum evidently contains autoantibodies against DIT-gastrin that interfere with RIA of gastrin.

Co-purification of bone resorbing activity and adenylate cyclase stimulating activity from human tumours associated with the humoral hypercalcaemia of malignancy

We have partially purified a tumour factor capable of stimulating both bone resorption in vitro and cAMP accumulation in osteoblastic ROS 17/2 cells from three human tumours associated with humoral hypercalcaemia of malignancy. Purification of tumour factor by sequential acid urea extraction, gel filtration and cation-exchange chromatography, reverse-phase high performance liquid chromatography followed by analytical isoelectric focussing provided a basic protein (pI greater than 9.3) with a molecular weight of approximately 13,000 as a major component of the final preparation which retained both the two bioactivities. Bone resorbing activity and cAMP-increasing activity in purified factor correlated with each other. cAMP-increasing activity of the factor was heat- and acid-stable, but sensitive to alkaline ambient pH. Treatment with trypsin destroyed cAMP-increasing activity of the factor. Synthetic parathyroid hormone (PTH) antagonist, human PTH-(3-34) completely inhibited the cAMP-increasing activity of the factor. The results suggest that this protein factor, having its effects on both osteoclastic and osteoblastic functions, may be involved in development of enhanced bone resorption in some patients with humoral hypercalcaemia of malignancy.

Procurement of radioiodinated glucose derivative and its biological character

Radiolabeled glucose derivatives are attracting great interest in the clinical field. Development of an analogous substrate labeled with a practical radionuclide, 123I, is most desirable, however, no radioiodine labeled glucose derivative has been reported as being chemically and biologically compatible. Thus, in the present study, a glucose derivative substituted at the C-2 position by a p-iodobenzyl group, a 2-O-(p-iodobenzyl)-D-glucose (IBG) was designed and its synthesis was carried out. A very easy and simple synthetic method was developed, and the obtained IBG showed appropriate purity and stability for its radioiodination. [125I]IBG was obtained by radioisotopic exchange reaction with high radiochemical purity and radiochemical yield, requiring no purification. The good in vivo and in vitro stability and the chemical and biological characteristic displayed by the new [125I]IBG stimulated the measurement of the brain uptake index (BUI). In the presence of glucose, brain uptake inhibition was detected, a good indication of a glucose carrier mediator for the transport of [125I]IBG through the blood-brain barrier, a similar feature to that of [14C]glucose or 3-O-[14C]methylglucose. The newly designed ligand IBG holds good promise for the study of regional cerebral glucose utilization, should the 123I become available.