Although rifampicin (RFP) is known to be one of the potent hepatic microsomal enzyme inducers, little has been reported about the detailed pharmacokinetics of glucocorticoids in patients under RFP therapy. In this paper, the metabolism of cortisol, prednisolone and dexamethasone were investigated comparatively by simultaneous injection of these glucocorticoids.
Eleven patients under RFP therapy, including 7 with tuberculosis together with collagen diseases and 4 with tuberculosis alone, were studied. Sixteen normal volunteers and 4 patients with collagen diseases not under RFP therapy were also examined as controls. After 1 mg of betamethasone was administered orally on the previous night for the suppression of endogenous cortisol, a mixed solution of 1mg each of cortisol, prednisolone and dexamethasone was given intravenously. Plasma steroid levels of periodically collected blood samples were determined by respective radioimmunoassay after extraction with dichloromethane and purification by paper chromatography.
Half-times of plasma disappearance (t1/2), metabolic clearance rates (MCR) and total apparent distribution volumes (V) of these glucocorticoids were calculated using the single compartment model.
The mean values of t1/2 of cortisol, prednisolone and dexamethasone in patients with collagen diseases under RFP therapy were 1.8±0.3 (Mean±SD) (p<0.05), 1.4±0.2 (p<0.001) and 1.3±0.3 hours (p<0.001), respectively, which were significantly shortened when compared with normal subjects (cortisol, 2.1±0.2; prednisolone, 2.5±0.7; dexamethasone, 3.5±1.0 hours). The MCR of cortisol, prednisolone and dexamethasone in these patients were 139±57,141±53 (p<0.01) and 722±137 l/day/m² (p<0.001), respectively, which were increased when compared with normal subjects (cortisol, 114±20; prednisolone, 75±25; dexamethasone, 153±45 l/day/m²). The metabolism of these glucocorticoids in patients with collagen diseases under RFP therapy were also accelerated when compared with those in patients with collagen diseases not under RFP therapy.
The t1/2 of cortisol, prednisolone and dexamethasone in patients with tuberculosis alone under RFP therapy were 1.3±0.3 (p<0.001), 1.4±0.5 (p<0.01) and 1.2±0.3 hours (p<0.001), respectively, which were significantly shortened when compared with normal subjects. The MCR of prednisolone and dexamethasone in these patients were significantly increased (136±72, p<0.05 and 868±226, p<0.001 l/day/m²) when compared with normal subjects.
When these data were expressed as percent of mean values in normal subjects, the mean %-t1/2 of cortisol, prednisolone and dexamethasone were 86%, 56% and 37%, and the mean %-MCR were 122%, 188% and 472%, respectively, in patients with collagen diseases under RFP therapy. The mean %-t1/2 of these glucocorticoids in patients with tuberculosis alone under RFP therapy were 62%, 56% and 34%, and the mean %-MCR were 105%, 181% and 567%, respectively.
The V of these glucocorticoids in patients under RFP therapy were almost the same as normal subjects except for that of dexamethasone, which was about twice as much as normal in patients both with or without collagen diseases.
Five patients who were examined again after discontinuance of RFP showed normalization of this accelerated metabolism of prednisolone and dexamethasone.
It may be concluded that marked differences in the degrees of accelerated metabolism between these glucocorticoids, the order of which was dexamethasone, prednisolone and cortisol, were observed in patients under RFP therapy. These results are very important in the concurrent use of glucocorticoid and RFP, especially when the tuberculosis therapy is needed in patients with collagen diseases under glucocorticoid therapy,

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We established an anti-thyroglobulin antibody-producing cell line using the peripheral lymphocytes from a patient with chronic thyroiditis. The method was based on preselection by “panning”, transformation by EB virus and twice clonings by “limiting dilution”.
The cells of the cloned cell line (Yo3CTX10) had neither E-receptor nor IgG·Fc-receptor but had C₃-receptor as shown by rosetting. We could not detect surface immunoglobulin, but we could detect cytoplasmic immunoglobulin (IgGλ) with FITC-stainings.
This cell line has continuously secreted anti-thyroglobulin antibody for 8 months, which was IgGλ as shown by immunoelectrophoresis and solid phase radioimmunoassay. The pattern obtained using the purified antibody showed two sharp bands (H, L-chains) in SDS polyacrylamide gel electrophoresis, but it showed six sharp bands in isoelectric focusing electrophoresis.
Thus we could establish an oligoclonal cell line producing IgGλ anti-thyroglobulin antibody.

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O,p′-DDD is used for the treatment of adrenocortical carcinoma and Cushing's disease. The inhibitory effect of this drug on the adrenal steroid biosynthesis has been described by many authors, but there are very few reports about the sites of action of this drug on adrenal steroid synthesis. This paper presents in vitro studies on adrenal steroidogenesis and hepatic steroid metabolism.
The effects of o,p′-DDD on adrenal 3β-hydroxysteroid dehydrogenase (3β-HSD), 11β-hydroxylase (11β-OHlase) and 18-hydroxylase (18-OHlase) were examined in vitro using mitochondrial and microsomal fractions prepared by standard centrifugation procedures from the homogenate of bovine adrenal cortices. The concentrations of o,p′-DDD inducing 50% inhibition of 3β-HSD, 11β-OHlase and 18-OHlase were 8×10^-6M, 1×10^-5M and 3×10^-6M, respectively. This study clearly demonstrates the marked inhibitory effects of o,p′-DDD on 3β-HSD in vitro, which was not described previously. The inhibitory effects of o,p′-DDD on these 3 enzymes were diminished by an addition of 0.05-0.5 mM of cofactor (NADPH or NAD). The results indicate that o,p′-DDD may reduce NADPH or NAD utilization, resulting in the inhibition of steroidogenesis.
The effects of o,p′-DDD on hepatic 5β-reductase were examined in vitro using rat liver homogenate. O,p′-DDD inhibits 5β-reductase, resulting in the decrease of conversion of cortisol to dihydrocortisol and tetrahydrocortisol at the concentration of 10^-3M.

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Using antisera against three kinds of cytoskeletal proteins (keratin proteins, actin protein and myosin protein) and thyroglobulin, immunoperoxidase staining was performed on the follicular cells of 30 patients with Hashimoto's thyroiditis. These patients were subdivided into three types by Woolner's classification : 9 patients of lymphoid type (L-type), 12 patients of oxyphilic cell type (O-type), and 9 patients of pronounced epithelial destruction type (P-type).
The results obtained were as follows : (1) In three-ninths to seven-twelfths of the patients of O-type and P-type, the cytoskeletal proteins were identified in the epithelial cells forming degenerating or atrophic thyroid follicles. In the patients of L-type, however, the cytoskeletal proteins which form large follicles containing much colloid were not found in the epithelium. (2) In some patients of O-type, keratin proteins were abundantly present in the epithelial cells with squamous cell metaplasia. (3) In the patients of L-type, thyroglobulin was found in most of the epithelium forming large follicles, but it was not found in those forming degenerating or atrophic follicles in the patients of O-type and P-type.

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Anti-triiodothyronine antibody was found in a case of rheumatoid arthritis associated with Hashimoto's thyroiditis.
The patient was a 40 year-old woman who had complained of polyarthralgia, jointswelling and stiffness for seven years. She had a rheumatoid nodule and showed a positive RA test. Radiographic changes of hands and wrists showed osteoporosis, erosions and narrowing of joint space. Nonsteroidal anti-inflammatory drugs had been used for seven years. The diagnosis of Hashimoto's thyroiditis had been made by open biopsy of the thyroid gland seven years before.
Serum T₄ TSH, TBG, free T₄, free T₃ and r-T₃ were all normal. On the other hand, serum T₃ level was almost unmeasurable by radioimmunoassay. Binding of ¹²⁵I-T₃ to the patient's serum was studied by using polyethylene glycol (PEG) and column chromato-graphy. By using the PEG method, the binding of ¹²⁵I-T₃ to the patient's serum was tenfold compared to control serum.
Sepandex G-25 column chromatography (0.9×1.5 cm) of ¹²⁵I-T₃ with the patient's serum in the presence of 0.1% ANS showed an early radioactive peak, while control serum did not show an early peak.
In the next experiments, the patient's serum was labelled with ¹²⁵I-T₃, mixed with human anti-IgG, IgM, IgA,λ, κ, incubated at 4°C for 20 hours and centrifuged for 20 min.
Strong binding to the anti-IgG and anti-λ was detected. The presence of this abnormal T₃-binding globulin in the patient's serum may have produced an undetectable T₃ level.

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To establish a detailed reevaluation system for infants who were recalled by a neonatal mass screening for congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, pregnanetriol (PT) and pregnanetriolone (PTL) in a single urine specimen combined with plasma 17α-hydroxyprogesterone (17-OHP) and 21-deoxycortisol (21-DOF) were determined by a simple method using glass capillary gas chromatography.
A pilot study of neonatal mass screening for CAH with a determination of “disc 17-OHP” value in dried blood on filter paper was carried out in Western Shizuoka Prefecture. During the study period (32 months), 37472 neonates were determined by mass screening, and 362 neonates proved to be abnormal candidates who needed further evaluations. From out of these candidates, 262 neonates responded with recall and were studied. Amongst these 262 neonates, 241 neonates visited directly our outpatient clinic at Hamamatsu University Hospital. The reevaluation conducted at our clinic included a physical examination, detailed family history, measurement of serum electrolytes, disc 17-OHP, plasma 17-OHP and 21-DOF values, and PT and PTL in a single urine specimen.
Consequently, 3 neonates appeared to be patients with CAH. Two of them were the salt-losing type and the other was the simple virilizing type. The rest of the candidates who received reevaluation were finally decided to be healthy neonates, indicating false positivity by mass screening.
Compared to the candidates who showed false positivity in the mass screening, the CAH patients had an apparently high urinary PT and PTL titer of ten or one hundred fold. Additionally, despite corticosteroid treatment in one case, significantly elevated levels of PT and PTL were detected.
To assay PTL was a more reliable parameter for the detection of CAH and for following up the candidates because PTL was not detectable in 63.3% of the false positive cases, suggesting that PTL was less likely to indicate false positive cases. PTL was detected at more than 0.01μg/ml urine in 19.4% of false positive cases, however, no case showed further elevation of PTL during the follow up period. In all false positive cases, PTL was not detectable until the age of six months.
Despite problems to be resolved, determination of urinary PTL titer is valuable for the detection of CAH patients. In addition, urinary PTL could be a good parameter for the further follow up of false positive cases in neonatal mass screening.

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The effects of Medroxyprogesterone acetate (MPA) and progesterone (P) on DNA and RNA contents of a human endometrial cancer cell line (Ishikawa) and a human breast cancer cell line (MCF-7) were studied using Flow cytometry.
The results were as follows.
1) MPA and P at a high dose of 10^-5M inhibited their cell cycle progression through the G₁ phase or G₁-S phase boundary and showed a decrease in the number of cells which underwent DNA synthesis and mitosis.
2) P at a low dose of 10^-7M showed the lengthening of cell cycle time in the S phase. MPA at 10^-7M had an inhibitory effect on the cell cycle progression of Ishikawa cells similar to that of a high dose of MPA whereas, in the case of MCF-7 cells, it showed a lengthening of duration in the S phase. Therefore, the dose-responsibility of these cells to MPA were shown to be different.
3) A high dose of MPA and P showed a decrease in the cytoplasmic and nuclear RNA contents. A low dose of MPA and P had no marked effect on the RNA contents.
From these results, it was clarified that MPA, especially at a high dose, could substantially inhibit RNA synthesis and DNA synthesis with a delay of the cell cycle progression in hormone responsive cancer cells.

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