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Site-specific suppressors of superoxide production (named S1QELs) in the quinone-reaction site in mitochondrial respiratory complex I during reverse electron transfer have been previously reported; however, their mechanism of action remains elusive. Using bovine heart submitochondrial particles, we herein investigated the effects of S1QELs on complex I functions. We found that the inhibitory effects of S1QELs on complex I are distinctly different from those of other known quinone-site inhibitors. For example, the inhibitory potencies of S1QELs significantly varied depending on the direction of electron transfer (forward or reverse). S1QELs marginally suppressed the specific chemical modification of Asp(160) in the 49-kDa subunit, located deep in the quinone-binding pocket, by the tosyl chemistry reagent AL1. S1QELs also failed to suppress the binding of a photoreactive quinazoline-type inhibitor ([(125)I]AzQ) to the 49-kDa subunit. Moreover, a photoaffinity labeling experiment with photoreactive S1QEL derivatives indicated that they bind to a segment in the ND1 subunit that is not considered to make up the binding pocket for quinone or inhibitors. These results indicate that unlike known quinone-site inhibitors, S1QELs do not occupy the quinone- or inhibitor-binding pocket; rather, they may indirectly modulate the quinone-redox reactions by inducing structural changes of the pocket through binding to ND1. We conclude that this indirect effect may be a prerequisite for S1QELs' direction-dependent modulation of electron transfer. This, in turn, may be responsible for the suppression of superoxide production during reverse electron transfer without significantly interfering with forward electron transfer.

NADH-quinone oxidoreductase (respiratory complex I) couples NADH-to-quinone electron transfer to the translocation of protons across the membrane. Even though the architecture of the quinone-access channel in the enzyme has been modeled by X-ray crystallography and cryo-EM, conflicting findings raise the question whether the models fully reflect physiologically relevant states present throughout the catalytic cycle. To gain further insights into the structural features of the binding pocket for quinone/inhibitor, we performed chemical biology experiments using bovine heart sub-mitochondrial particles. We synthesized ubiquinones that are oversized (SF-UQs) or lipid-like (PC-UQs) and are highly unlikely to enter and transit the predicted narrow channel. We found that SF-UQs and PC-UQs can be catalytically reduced by complex I, albeit only at moderate or low rates. Moreover, quinone-site inhibitors completely blocked the catalytic reduction and the membrane potential formation coupled to this reduction. Photoaffinity-labeling experiments revealed that amiloride-type inhibitors bind to the interfacial domain of multiple core subunits (49 kDa, ND1, and PSST) and the 39-kDa supernumerary subunit, although the latter does not make up the channel cavity in the current models. The binding of amilorides to the multiple target subunits was remarkably suppressed by other quinone-site inhibitors and SF-UQs. Taken together, the present results are difficult to reconcile with the current channel models. On the basis of comprehensive interpretations of the present results and of previous findings, we discuss the physiological relevance of these models.

Hypercholesterolemia is one of the most representative disorders of the common diseases. To evaluate the prevalence of hypothyroidism in the population of adult hypercholesterolemia, we prospectively examined the thyroid function in patients with untreated or treated hypercholesterolemia as a multi-center survey. Subjects were the patients who were treated with some antilipemic agents or the untreated patients whose total cholesterol (TC) was over 220 mg/dL and/or LDL-cholesterol (LDL-C) over 140 mg/dL. Among 737 cases recruited, 725 cases (300 males and 425 females) participated in the survey including the thyroid function test. The patient's backgrounds include hypertension (51%), diabetes mellitus (49%), fatty liver (17%), smoking (15%), and habitual drinking (10%). The 72% of the patients were treated with some antilipemic agents and the mean values of TC, LDL-C, triglyceride (TG), HDL-cholesterol (HDL-C), and LDL-C/HDL-C ratio (L/H) were 204.5 mg/dL, 119.6 mg/dL, 144.4 mg/dL, 60.7 mg/dL and 2.25, respectively. The primary hypothyroidism was seen in 27 cases (3.7%) (11 males, 16 females) with subclinical hypothyroidism in 17 cases (2.4%) and overt hypothyroidism in 10 cases (1.4%). The central hypothyroidism was seen in 4 cases (0.6%). The prevalence of hypothyroidism was 4.3% in patients with hypercholesterolemia. Taking account of the large number of patients with dyslipidemia and importance of avoiding unnecessary administration and associated adverse effects, evaluation of the thyroid function could be warranted in patients with dyslipidemia although cost-benefit issues waits further investigation.

Miscible blends of three crystalline polymers, namely poly(butylene succinate) (PBS), poly(ethylene succinate) (PES), and poly(oxyethylene) (POE), exhibited interpenetrating spherulites, where a spherulite of one component grows inside the spherulites of other components. PBS and PES were immiscible above the melting points, Tm, of these substances, while ternary blends with POE showed miscibility, which depended on the molecular weight of POE. PBS and PES exhibited the same spherulitic growth process as in a miscible binary blend when they were crystallized from a homogeneous ternary melt. Spherulites of PBS, which is the highest-Tm component, filled the whole volume first when a miscible ternary blend was quenched below Tm of POE, the lowest-Tm component. Then, the blends showed either two types of crystallization processes. One was successive nucleation and growth of PES and POE spherulites, that is, PES nucleated and developed spherulites inside the PBS spherulites and then POE spherulites grew inside the interlocked spherulites of PBS and PES. The other was simultaneous growth and the formation of interpenetrating spherulites of PES and POE inside the PBS spherulites. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 706–711, 2010

Malnutrition is a significant factor in the development of pressure ulcers and many nutritional guidelines for preventing pressure ulcers have been published. However, few clinical investigations have examined the energy required to heal pressure ulcers. The aim of the present study was to investigate the relationship between nutritional intake and improvement of pressure ulcers. Total calories, which were supplied by mouth through a feeding tube and via venous alimentation were examined for 40 hospitalized bedridden inpatients who had pressure ulcers. Of these patients, 21 whose wounds improved or healed and 19 whose wounds became worse or did not improve were eligible for this retrospective study. Pressure ulcers in patients who received more than 30 kcal/kg per day improved or healed, while those of patients who received less than 20 kcal/kg per day worsened or failed to improve. Furthermore, intake of 30 kcal/kg per day enabled serum albumin levels to improve. Energy intake of 30 kcal/kg per day is comparable to the predicted total energy expenditure and is thought to be essential for improving pressure ulcers in bedridden patients .

To examine whether serum resistin concentrations are associated with metabolic or inflammatory markers in patients with type 2 diabetes mellitus, we examined serum concentrations levels and metabolic or inflammatory markers in 56 patients with type 2 diabetes mellitus and 41 healthy subjects. Serum levels of resistin, serum amyloid A, and soluble vascular cell adhesion molecule-1 were measured by enzyme-linked immunosorbent assay. Serum resistin levels were significantly elevated in diabetic patients compared with those in healthy subjects. Serum resistin concentrations did not correlate with body mass index; however, there was a significant positive correlation between resistin and soluble vascular cell adhesion molecule-1 in diabetic patients. Based on the present results, we conclude that resistin appears to be associated with vascular inflammatory markers in patients with type 2 diabetes mellitus.

本稿の課題は、寝屋川市の教師殺傷事件に関する諸報道の分析を通じて、それらの言説が孕む諸問題を明らかにするとともに、現代の少年事件をどうみるか、このような悲劇を繰り返さないために私たち大人に何が求められているのか、といった課題について、メディア論ならびに知識論の視点から考察を加えることにある。そして同時にそれは、別様の社会や教育への想像力を枯渇させた現代社会において、私たち自身の社会的構想力を取り戻すための一つの試みでもある。

The spherulitic growth of poly(ethylene oxide) (PEO) was found to continue in the spherulites of poly(butylene adipate-co-butylene succinate) (PBAS) in the simultaneous spherulitic growth process of the two components in PBAS/PEO blends. This phenomenon, namely the formation of interpenetrating spherulites (IPS), was analyzed on the basis of birefringence observed by polarizing optical microscopy. The growth direction of PEO lamellae in the PBAS spherulites was found to be along the preexisting PBAS lamellae. PEO crystals also nucleated inside PBAS spherulites and showed spherulitic growth in them at relatively high crystallization temperatures. The conditions for realizing IPS were also discussed. Miscibility in these novel crystalline/crystalline polymer blends in the molten state was confirmed by differential scanning calorimetry and optical microscopy.

本稿では、学生の学習観・授業観に揺さぶりをかけ、あらためて大学教育とは何か、どうあるべきかを学生とともに探求することを課題として行った2003年度前期専門科目「教育人間学」の授業実践を紹介する。さらにそこから、学生の真の教育ニーズとは何かを考察したい。

The accumulation of activated CD4+ T cells and antigen (Ag)-dependent cellular interactions between thyrocytes and CD4+ T cells have been determined in thyroid gland from patients with Graves' disease. The Fas/Fas ligand (FasL) interaction between antigen-presenting cells and T cells regulates the apoptosis of the former cells triggered by the latter cells. The inhibition of Fas-mediated apoptosis in thyrocytes could be a underlying mechanism of hyperplasia of thyrocytes in patients with Graves' disease. We investigated the potential role of Fas/FasL interaction between thyrocytes and CD4+ T cells in the induction of Fas-mediated apoptosis of the former cells induced by the latter cells. The presence of only a few specific T cells responsive to a putative autoantigen has hampered the investigation of specific T cell activation toward antigen-presenting cells (APCs). Therefore, we used a superantigen, staphylococcal enterotoxin B (SEB), to examine specific T cell activation toward thyrocytes in vitro since it stimulates a large proportion of T cells with particular Vbeta elements. Spontaneous apoptosis of thyrocytes in culture was not found even in the presence of various kinds of cytokines. In contrast, a clear induction of Fas-mediated apoptosis by anti-Fas IgM was determined in interferon-gamma (IFN-gamma)-stimulated thyrocytes. In addition, a significant cytotoxicity of purified CD4+ T cells toward IFN-gamma-stimulated thyrocytes in the presence of SEB was induced, and the addition of anti-HLA-DR and -DQ monoclonal antibodies (mAbs) or blockade of the Fas/FasL interaction reduced this cytotoxicity. FasL expression of CD4+ T cells cocultured with IFN-gamma-stimulated thyrocytes in the presence of SEB was clearly induced. Furthermore, the addition of mAbs against CD54 and CD58 inhibited both cytotoxicity and FasL expression of CD4+ T cells. The cytotoxicity of CD4+ T cells toward IFN-gamma-stimulated, SEB-pulsed thyrocytes was markedly inhibited when we used thyrocytes cultured with IFN-gamma in the presence of thyroid-stimulating hormone (TSH) as target cells. Our results suggest that 1) CD4+ T cells were activated by thyrocytes expressing MHC class II molecules in an SEB-dependent manner and then expressed FasL. 2) These activated FasL+ CD4+ T cells killed thyrocytes by interacting with Fas on thyrocytes and FasL on activated CD4+ T cells. The presence of costimulating molecules such as CD54 and CD58 on thyrocytes was also necessary to generate activated FasL+ CD4+ T cells. 3) Since the actions of thyroid stimulating antibody (TSAb) toward thyrocytes are similar to those of TSH, one goitrogenic activity of TSAb may, in part, be due to the inhibitory effect on Fas-mediated apoptosis of thyrocytes triggered by activated CD4+ T cells.

Apoptosis, a physiological process of cell death, may modulate the mass of the thyroid gland. We investigated the role of apoptosis and the possible involvement of Fas/Fas ligand (FasL) system in apoptosis during goiter formation and involution in a rat model of goiter. Rats were fed a low iodine diet and a goitrogen, 6-propyl-2-thiouracil, to induce goiter. Rats with goiter were then fed a high iodine diet to study the phase of involution. We examined the presence of apoptosis by electron microscopy (EM) and terminal deoxy-UTP nick end labeling (TUNEL). We also investigated the association between Fas and FasL expression and thyrocyte apoptosis using immunohistochemistry and Western blotting. To evaluate the proliferation of thyrocytes, proliferating cell nuclear antigen was examined immunohistochemically. The number of apoptotic cells increased during goiter formation and the early stage of involution, which were also associated with increased number of Fas-positive thyrocytes, and some of these cells c...

OBJECTIVES Widespread amyloid deposition in the thyroid gland causes diffuse, clinically apparent enlargement of the thyroid (amyloid goitre: AG). The aim of this study was to clarify the abnormalities of thyroid function in patients with AG. DESIGN Thirty patients with secondary amyloidosis were retrospectively analysed. Their thyroid status was evaluated using the results of routine thyroid function tests and measurement of thyroid autoantibodies. Thyroid needle biopsy was carried out to identify amyloid deposition in the thyroid gland. RESULTS Thyroid enlargement was observed in 19 (63%) of 30 patients with amyloidosis. Eleven of these 19 patients had a thyroid biopsy and/or autopsy and amyloid deposition was histologically revealed in 10 (defined as AG) of these 11 patients. Nine of 10 patients (90%) with AG had abnormalities of thyroid function, including five patients with hypothyroidism, one with hyperthyroidism, one with transient hypothyroidism, and two with low T3 syndrome. Five had thyroid autoantibodies. The patient with hyperthyroidism had positive thyroid stimulating antibody (TSAb) and high 131I thyroidal uptake, suggesting the coexistence of Graves’ disease. Another patient suffered from thyroidal pain and showed transient hypothyroidism, high level of serum thyroglobulin and low thyroidal uptake of 123I, the clinical course being compatible with subacute thyroiditis. CONCLUSIONS The incidence of thyroid abnormalities accompanied by AG, although asymptomatic, is unexpectedly high. Thyroid function should therefore be regularly assessed during follow-up of patients with systemic amyloidosis.

The growth regulatory activity of transforming growth factor-beta 1 (TGF beta 1) was studied in a clonal strain of thyroid papillary carcinoma cell (NPA). Despite the presence of TGF beta 1 and its receptor messenger RNA in thyroid carcinoma, the molecular mechanism of TGF beta 1 action on cell growth of thyroid carcinoma has not yet been elucidated. Exogenously added TGF beta 1 inhibited DNA synthesis and cell growth in a dose- and time-dependent manner at concentrations of 0.1-10 ng/ml. TGF beta 1 inhibited not only basal but also fetal bovine serum-stimulated cell proliferation. Steady state levels of c-myc messenger RNA transcripts were inhibited by TGF beta 1 after 0.5-h treatment. Antisense, but not sense, c-myc oligodeoxynucleotides also caused suppression of NPA cell growth in a dose-responsive manner. Transfection studies of the 5'-up-stream flanking region (UFR) of c-myc/chloramphenicol acetyltransferase chimera genes suggest the presence of a TGF beta 1-responsive DNA element in the 2.3-kilobase c-myc 5'-UFR. Deletion mutant studies indicate the element lies between -106 to 70 relative to the P1 transcription start site. Studies with the gel mobility shift assay using 23-basepair double strand DNA showed the presence of at least two nuclear factors in NPA cell. TGF beta 1 treatment did not cause any alteration in TGF beta 1-induced mobility; however, the reduction of a positive band was selectively observed during 30 min to 2 h after treatment with TGF beta 1. In contrast, the position and intensity of another band were not altered by TGF beta 1 treatment. These results demonstrate that the inhibition of a nuclear factor binding to the c-myc 5'-UFR and subsequent suppression of c-myc gene expression are directly involved in the antiproliferative action of TGF beta 1 in NPA cell growth.

It is well known that the TSH receptor (TSHR) undergoes homologous desensitization. That is, prolonged stimulation of thyroid cells with TSH attenuates the cAMP response to subsequent TSH stimulation. However, the existence of homologous desensitization of the recombinant TSHR expressed in nonthyroidal eukaryotic cells is controversial. In the present studies, therefore, we first investigated whether or not the TSHR was desensitized by TSH in 293 human embryonal kidney cells, a cell line in which the LH/CG receptor (LH/CGR) is reported to undergo homologous desensitization. The wild type (wt) TSHR and the wt-LH/CGR stably expressed in 293 cells bound to their respective hormones with high affinity and produced a dose-dependent intracellular cAMP response to hormone stimulation. Pretreatment of cells expressing the TSHR or the LH/CGR with their respective hormones attenuated the cAMP response to subsequent hormone stimulation without down-regulation of the receptors, demonstrating that the TSHR, as well as the LH/CGR, undergoes homologous desensitization in 293 cells. With this cell type expressing mutant TSHRs, we then studied some aspects of the molecular mechanism of TSHR desensitization and compared our data to those obtained with the beta-adrenergic receptor (beta-AR), which is widely regarded as the prototype for receptor desensitization. We cotransfected the wt-TSHR and a chimeric receptor consisting of the LH/CGR extracellular ligand binding domain with the TSHR transmembrane/cytoplasmic signal transducing region. These two receptors have distinct hormone specificities but share common signal regulatory mechanisms. We observed that, like the beta-AR, only hormone-occupied receptor is likely to be involved in homologous desensitization. On the other hand, studies with a truncated TSHR indicated that, in contrast to the beta-AR, the serine/threonine-rich region in the carboxyl two thirds of the cytoplasmic tail of the TSHR is not involved in homologous desensitization.

In the present studies, the long term effects of IFNα on thyroid function and thyroid autoantibodies were evaluated in 42 patients with chronic viral hepatitis type C treated with IFNα for at least 4 months. Before IFN treatment, 41 patients tested were all euthyroid. Five (12%) out of 24 patients tested had positive tests for thyroid autoantibodies. MCHA/TPOAb was detected in all 5 and TGHA/TGAb in 3 out of these 5 patients. Six to 10×106 units (U) of recombinant or natural IFNα were given intramuscularly daily for the first 2 to 4 weeks, followed by 3 to 10×106 U thrice weekly for the subsequent 14 to 22 weeks. Thyroid dysfunction and/or rises in titers of thyroid autoantibodies were observed in 6 patients during IFNα treatment; clinically overt thyroid dysfunctions, destructive thyroiditis and thyrotoxicosis of unidentified etiology, developed in 2 patients 4 to 5 months after start of IFN treatment, subclinical hypothyroidism with a slight increase in serum TSH concentrations but no serum thyroid hormone alternations was observed in 2 patients, and increases in titers of thyroid autoantibodies without thyroid dysfunction were found in 2 patients. Thus, IFNα exacerbated thyroid autoimmunity exclusively in all patients with positive tests for thyroid autoantibodies prior to treatment, but did not induce thyroid autoimmunity in thyroid autoantibody-negative patients. These data suggest that the prolonged IFNα therapy can lead to exacerbation of thyroid autoimmunity in susceptible (thyroid autoantibody-positive) patients.

In this paper, we report a case of rheumatoid arthritis (RA) with Sjögren's syndrome (SS) in which the patient developed subacute cutaneous lupus erythematosus (SCLE). A 72-year-old woman, who had a 10-year history of RA and SS, developed annular erythematosus skin lesions involving her face, neck, and extremities. Serological tests showed that anti-SS-A/Ro antibodies and anti-DNA antibodies were elevated. Histological examination of the skin lesions demonstrated the liquefaction degeneration of the epidermal basal layer and perivascular mononuclear cell infiltration. The diagnosis of SCLE was made based on the clinical features and skin histological findings. The disease was well controlled with intralesional and systemic corticosteroids and became quiescent. This case report demonstrates the concurrence of sero-positive RA, SS, and SCLE, which seems to be quite rare.

The benefit of I-131 therapy of metastatic differentiated thyroid carcinoma is controversial. To evaluate usefulness of I-131 therapy for metastatic differentiated carcinoma, 83 patients were chosen from 276 patients with differentiated thyroid carcinoma who were operated at Nagasaki University Hospital since 1960 according to the following criteria; (i) thyroids totally removed, (ii) existence of metastases at total thyroidectomy, (iii) the cause of death related to thyroid carcinoma if the patient died. The usefulness of I-131 therapy was evaluated by analysis of survival during 10 years following total thyroidectomy. In patients without remote metastases, the survivors and nonsurvivors were 37 and 2 in those without I-131 therapy (Group I), and 11 and 1 in those with I-131 therapy (Group II), respectively. There was no significant difference between the two groups. In patients with remote metastases, the survivors and non survivors were 9 and 1 in I-131 treated patients who had I-131 accumulation in the metastases with tracer doses (Group III-1), 1 and 11 in I-131 treated patients without I-131 accumulation in metastases with tracer doses (Group III-2), and 4 and 6 in non I-131 treated patients whose metastases were not examined for I-131 accumulation (Group IV), respectively. The prognosis was best in Group III-1 and followed by Group IV and Group III-2 in this order in patients with remote metastases. There was no significant difference in age and sex among the groups and in pathological findings of carcinoma. These results suggest that I-131 therapy may be useful for patients with remote metastases which accumulate I-131 with tracer doses but not for those patients who do not accumulate I-131 and that I-131 accumulation in metastases with tracer doses may be of prognostic significance.

Although thyrotropin is known to regulate thyroid cell differentiation and proliferation, human thyroid carcinoma cells are relatively insensitive or resistant to TSH stimulation. The expression levels of TSH receptor are significantly lower in carcinoma tissues than in normal tissues. Furthermore, in vitro human thyroid cell growth is not regulated by TSH itself. We, therefore, isolated neomycin-resistant stable human thyroid carcinoma cell (WRO cell) transfectants overexpressing intact human TSH receptor to evaluate the functional role of TSH receptor on carcinoma cells. Southern blot analysis confirmed incorporation and amplification of human TSH receptor complementary DNA sequences into genomic DNA. Northern gel analysis and reverse transcriptase-polymerase chain reaction analysis revealed the presence of specific TSH receptor messenger RNA (4.0 kilobases), and the specific binding and the affinity of [125I]TSH on stably transfected WRO cells were demonstrated compared to wild type. Nevertheless, impaired cAMP production to transfectants by TSH was observed. cAMP production was confirmed after stimulation of both wild type and transfectants by forskolin, cholera toxin, and isoproterenol. In contrast, TSH could affect the cytoplasmic calcium mobilization immediately after the addition of TSH to WRO transfectants. These results suggest that the impairment of TSH action on human thyroid carcinoma cells is not due to a major structural abnormality of the TSH receptor, reduction in the receptor number, or receptor affinity, but much more likely due to a TSH receptor-guanyl nucleotide-binding protein coupling defect.

Corrosion fatigue crack propagation of ship structural steel plates such as KA36 (TMCP) has been investigated from a viewpoint of hydrogen embrittlement. Hydrogen permeation coefficient was measured to be about 0.11 μA/cm in sour crude oil with H2S and H2O. It was simulated by cathodic hydrogen charging in some electrolytic solution.In this condition, the crack propagation rate of KA36 (TMCP) steel was accelerated as well as in sour crude oil. It increased with an increase in hydrogen permeation coefficient. It was well coincident with the spacing per cycle of brittle striation, which was observed in the accelerated crack propagation area in both conditions. The crack propagation rate, da/dN, increased with a decrease in the cycle of stress.Hydrogen content near the crack tip in the, ΔK of 37 MPa√m might be about one order of magnitude more than that in base material, which was estimated by both the observation of dislocation density in the plastic deformation region and the measurement of hydrogen diffusion coefficient of cold rolled steels. As the result, the hydrogen content in steel near the crack tip in high ΔK region might be approximately 0.1 mass ppm.Considering these results, it was concluded that the environmental enhancement of the crack propagation rate in sour crude oil was due to hydrogen embrittlement.

We have explored scid mice as an in vivo model to study lymphocyte function and autoantibody production in patients with autoimmune thyroiditis and thyroid peroxidase (hTPO) autoantibodies. Patient's peripheral blood mononuclear cells (PBMC) were transplanted into scid mice via intraperitoneal injections and human immunoglobulin G (hIgG) and thyroid autoantibody levels in the murine sera were monitored for a minimum of 3 months after transplantation. Human IgG reached maximum serum levels of3,000 micrograms/ml (mean +/- SEM = 1,199 +/- 354 micrograms/ml) after an average of 6.5 weeks. In reconstituted mice (hereafter named At-Scid-hu) substantial titers of anti-hTPO of up to 0.51 (ELISA index, normal range0.02) were observed over a period of 1-2 months, followed by a gradual decline. Immunization of AT-Scid-hu mice with immunogenic, recombinant human hTPO (rec-hTPO) failed to enhance hTPO-Ab levels. Furthermore, there was no correlation between the magnitude of human IgG in the murine serum and concomitant levels of anti-hTPO. Murine thyroid function was unaffected by the transplantation of PBMC, as evidenced by normal serum thyroxine (T4) levels, and lack of specific pathologic changes in the thyroid. These data indicate, for the first time, the potential for longer-term human thyroid autoantibody secretion in the scid mouse reconstitution model allowing for further investigation of the regulatory factors inpinging on the human B cells surviving in the murine environment.(ABSTRACT TRUNCATED AT 250 WORDS)

Strains of rat differ in their susceptibility to experimental autoimmune thyroiditis (EAT). We recently observed that the normal Wistar rat has lymph node (LN) T cells which recognize the newly available cloned Wistar thyroid cell line (WRT) and/or rat thyroglobulin (rTg). We have now cloned thyroid-specific T cells and characterized their interaction with the WRT target cell. Twenty-three T cell clones were tested for their reactivity to syngeneic thymocytes, WRT cells alone, or WRT cells with thymocytes. All the clones were of the CD4+CD8- phenotype. Seven of 23 T cell clones proliferated in the presence of WRT cells alone or with the combination of WRT cells and thymocytes, exhibiting stimulation indices of 1.5 to 5. In all but one of the T cell clones responding to WRT cells alone was there no evidence that the additional presence of thymocytes supplied a stronger "second" proliferative signal than the WRT cells. These WRT-reactive clones which were able to be more extensively characterized were MHC class II restricted, secreted rat interferon (IFN)-gamma in response to WRT cell exposure, and one clone showed cross-reactivity with rTg antigen. Induction of WRT cell MHC class II antigen by prior treatment with IFN-gamma failed to further enhance the WRT cell-induced T cell proliferation. These data provide the first evidence for direct antigen presentation by thyroid epithelial cells (TECs) in the absence of other antigen-presenting cells. Furthermore, they provide evidence that TECs are able to provide the appropriate "second" signals required for T cell activation and successful autoantigen presentation.

The paper presents a numerical method for solving an initial-boundary value problem of heat equations. The boundary matrix method, which is a kind of boundary element method, is formulated for the one-dimensional problem. The solution procedure is applied to two-and three-dimensional problems with the local one-dimensional method. Although the present method is a kind of implicit method, it is easy to describe it with an explicit form. It means that it is unnecessary to solve a large linear system to proceed the numerical time integration. The present algorithm suits a vector computer since two-and three-dimensional problems are reduced to one-dimensional problems. We show some numerical examples to verify the method, numerically and discuss the ratio of vectorization on the supercomputer VP30E. Consequently, we develop the program whichi has 99.6% vectorization.

To investigate expression of members of the Toll-like receptor (TLR) family in peripheral blood mononuclear cells (PBMC) in patients with systemic lupus erythematosus (SLE).We analyzed PBMC from 14 patients with SLE and 15 healthy subjects. The surface expressions of TLR2 and TLR4 and intracellular expression of TLR9 on PBMC were analyzed by flow cytometry.Although TLR4 expressions on CD14+ monocytes were not significantly different between healthy subjects and patients with SLE, TLR2 expressions on monocytes were reduced in patients with SLE compared to healthy subjects. Intracellular TLR9 expression levels of CD19+ B lymphocytes were significantly elevated in patients with SLE. However, the TLR9 expression levels of plasmacytoid dendritic cells were not significantly different between these patients and healthy subjects.Our results show that human peripheral blood B cells express TLR9 and that its expression is increased in patients with SLE. This upregulated expression of TLR9 in B cells may be related to the abnormal B cell hyperactivity in patients with SLE.

We report a patient with idiopathic portal hypertension (IPH) associated with systemic sclerosis (SSc) and Sjogren's syndrome. A 72-year-old Japanese woman was admitted to our hospital because of Raynaud's phenomenon, sclerodactyly, and dyspnea. The patient had splenomegaly, esophageal varices in the absence of extrahepatic portal obstruction, and cirrhosis of the liver. Immunological studies revealed positive anti-nuclear antibodies and high titers of anti-Scl-70, anti-SS-A, anti-centromere, and anti-mitochondrial M2 antibodies. Histological examinations of the liver biopsy specimen revealed stenosis and loss of small portal veins without findings of primary biliary cirrhosis. The patient was diagnosed as having IPH associated with SSc and Sjogren's syndrome. These observations suggest an immunological role in the pathogenesis of IPH.

We have previously demonstrated that thyrocytes from patients with Graves' disease induce autologous peripheral blood T cell proliferation in response to soluble antigens, and a synergistic augmentation of T cell response by adding suboptimal numbers of monocytes. In the present study, we examined the role of costimulatory molecules, expressed on the surface of thyrocytes and intrathyroidal mononuclear cells, in antigen-specific T cell proliferation. Intercellular associated molecule (ICAM)-1 and lymphocyte function associated antigen-3 were constitutively expressed on the surface of both normal and Graves' thyrocytes. However, ICAM-2, vascular cell adhesion molecule-1, B7-1, and B7-2 were not detected and induced by cytokines. B7-1, was expressed on intrathyroidal monocytes only, while B7-2 was present on intrathyroidal lymphocytes, peripheral blood monocytes, and intrathyroidal monocytes. Furthermore, the density of B7-2 was higher on intrathyroidal monocytes than on peripheral blood monocytes. The intensity of CD28 expression on intrathyroidal CD8bright+ cells was less than that on peripheral blood CD8bright+ cells. The antigen-specific T cell response induced by thyrocytes was blocked completely by anti-human leukocyte antigen-DR monoclonal antibody (mAb) and partially by anti-ICAM-1 mAb and anti-lymphocyte function associated antigen-3 mAb. Furthermore, the synergistic augmentation of T cell response, induced by the addition of suboptimal number of monocytes, was suppressed completely by combining anti-B7-1 mAb and anti-B7-2 mAb, to a level equivalent to that observed when thyrocytes were used alone as antigen-presenting cells. Our results suggest that T cell proliferation was induced by cooperation of thyrocytes and infiltrating professional antigen-presenting cells.

Using a syngeneic Wistar rat model we have shown that the Wistar rat thyroid (WRT) cell line causes significant and specific proliferation of lymph node T cells from normal Wistar rats, and of splenic T cells from a thyroiditis prone line of BB/W rats, when cultured in the presence of irradiated feeder cells. These T cell responses were associated with a marked increase in the number of CD8+ T cells. However, using normal Wistar rat T cells which had been previously exposed to WRT cells, rested and then re-exposed to WRT cells as antigen, we consistently found that the T cell population had been rendered unreactive, or anergic, to further thyroid cell stimulation. However, if recombinant rat IL-2 was added to the cultures, then T cell responsivity was seen on re-exposure to WRT cells. The lymphopenic BB/W rat also had T cells which showed a primary T cell response to the WRT cell line accompanied by a marked increase in CD8+ T cells. In contrast to the Wistar rat T cells, the BB/W T cells retained a proliferative responsiveness to WRT cells on re-exposure although such responsiveness could also be markedly enhanced with IL-2. These data suggested that antigen-mediated inhibitory signals were induced in normal Wistar rat T cells by the syngeneic WRT cell line, independent of the presence of co-stimulatory molecules. Furthermore, the thyroiditis prone BB/W rat T cells appeared to be less responsive to such anergy induction, perhaps contributing to their susceptibility to autoimmune thyroid disease.

We report a 50-year-old female who suffered from reversible hypothyroidism accompanied by isolated ACTH deficiency. There were no findings indicating a complication of autoimmune thyroiditis. Replacement of maintenance dose of glucocorticoid not only led to improvement of thyroid function, but also caused a transient decrease in T 3 and an increase in reverse T 3 , suggesting that chronic cortisol deficiency may impair thyroid function, and that the maintenance dose, as well as pharmacological doses of glucocorticoids may influence T 4 deiodination. The findings of this case suggest that thyroid function should be re-evaluated to avoid unnecessary replacement of thyroid hormone, a few months after glucocorticoid replacement.

Recently, highly purified bovine thyrotropin (bTSH) of pituitary origin, as well as recombinant human (h) TSH free of lutropin (LH) contamination, has been reported to activate the LH/choriogonadotropin receptor (LH/CGR). These data challenge the concept of TSH specificity for its own receptor. We, therefore, re-evaluated these data using, as targets, the recombinant hTSH and rat LH/CGRs stably expressed in Chinese hamster ovary (CHO) cells. Partially purified bTSH (2 IU/mg protein) and, to a lesser degree, highly purified bTSH (30 IU/mg protein) increased intracellular cAMP levels in CHO-LH/CGR cells (an EC50 of 0.2 and > 20 mIU/ml, respectively). In contrast, recombinant hTSH (up to 1 IU/ml) did not. All three TSH preparations increased cAMP levels to the same extent in CHO-TSHR cells (an EC50 of 0.3 mIU/ml). Furthermore, we observed only nonspecific, low affinity TSH binding for CHO-LH/CGR cells and also for CHO cells transfected with the expression vector alone (a Kd of 100 nM), although both high and low affinity TSH binding was demonstrated in CHOT-SHR cells (a Kd of 0.3 and 100 nM, respectively). These data indicate that even highly purified bTSH of pituitary origin contains significant amounts of LH, and that TSH itself does not appear to activate the LH/CGR.

A prospective study was conducted on 10 normal male volunteers to investigate the effect of the administration of excess iodide on thyroid volume. After 1 week of dietary iodide restriction, all subjects were given daily oral doses (27 mg daily total iodine dose) of licorice lecithin-bound iodine tablets for 4 weeks. Thyroid function studies, total serum iodine concentration, and urinary iodine excretion were monitored. Thyroid volume was measured by high resolution echoscanner before treatment, on the day of the last treatment, and 1 month after the treatment. There was a significant rise in serum TSH levels, with a small decline in serum free T4 concentration during iodide administration; the values remained within the normal range except for two subjects. Serum thyroglobulin levels were increased in parallel with serum TSH levels, which became higher than normal after 1 week of treatment. The volume of the thyroid gland became significantly enlarged after 28 days of iodide intake. When iodide was discontinued, thyroid volume and function returned to baseline levels within 1 month for all subjects. This is the first documentated objective evidence that the compensatory rise in serum TSH in response to iodide administration elicits reversible thyroid hypertrophy in normal subjects.

The effect of retinoic acid (RA) on thyroid peroxidase (TPO) and thyroglobulin (Tg) gene expression was investigated in cultured human thyrocytes. Thyrocytes dispersed from Graves' thyroid tissues were incubated with TSH 5mU/ml and RA 0, 0.01, 0.1, 1.0 microM for 72 h respectively. The samples were then subjected to Northern gel analysis. Northern gel analysis using the specific cDNA probes showed that RA suppressed the accumulation of TPO and Tg mRNA stimulated by TSH in a time- and dose-responsive manner. Furthermore, RA inhibited forskolin and 8-Bromo-cyclic-AMP-induced TPO and Tg gene expression, suggesting a distal action site for these cAMP mediated gene expressions. Immunoprecipitation analysis using the specific monoclonal antibodies showed that TSH increased newly synthesized 100, 75, 36-kDa [35S] TPO. The increased de novo TPO was markedly inhibited by RA. Tg secretion from monolayer cultures was measured by radioimmunoassay. RA also inhibited TSH-induced Tg secretion in a dose dependent manner. RA did not affect [3H] thymidine uptake into primary cultured human thyrocytes. In conclusion, RA inhibits the synthesis of TPO and Tg via the suppression of thyroid-specific gene expression although the exact site of RA action on these genes in human thyroids remains to be further elucidated. These results suggest that RA may play a regulatory role in Tg and TPO gene expression, subsequently resulting in the suppression of thyroid hormone synthesis.

We report a 42-year-old Japanese woman with Recklinghausen's neurofibromatosis 1 (NF1) who developed mixed connective tissue disease (MCTD). Previously experiencing good health without an increase in subcutaneous nodules, she presented with Raynaud's phenomenon, swollen hands and polyarthralgia Clinical examination revealed a high titer of anti-RNP antibody, and she was thus diagnosed as having MCTD. She was treated with oral prednisolone (10 mg/day) and her symptoms improved rapidly. Since the association of MCTD and NF1 has not been reported previously, we concluded that this association is rare. We also discussed the association of NF1 and autoimmune diseases including MCTD.

In order to further evaluate the role of TSH in the proliferation and the differentiation of human thyroid carcinoma cells, we have analyzed the function of the TSH receptor in the established thyroid carcinoma cell lines NPA and WRO. The TSH signal transduction system in the carcinoma cells was also compared with that in normal thyroid cells. Although unresponsiveness to bovine and human TSH was demonstrated by measurement of cAMP production and [3H]thymidine incorporation after treatment of TSH, cAMP production was induced after stimulation of these cells by forskolin, cholera toxin, and isoproterenol. Specific binding to 125I-TSH was demonstrated in both NPA and WRO cells in addition to the existence of a TSH receptor mRNA and thyroglobulin mRNA species, although thyroid-specific gene expression in these cells was not regulated by TSH. These findings suggest that the unresponsiveness to TSH in these cells may be due to an abnormality of TSH receptor-G protein coupling rather than to a decreased level of TSH-receptor expression or a Gs protein abnormality.

A 65-year-old Japanese man who suffered from secondary hypopituitarism due to Rathke's cleft cyst is reported. Although computed tomography failed to detect any pituitary abnormality, magnetic resonance imaging demonstrated the presence of a cystic intrasellar mass, initially suggesting craniopharyngioma or abscess. Operative findings revealed Rathke's cleft cysts within the pituitary fossa which resulted in secondary hypopituitarism. Among cases of secondary hypopituitarism with abnormal findings in the pituitary, symptomatic Rathke's cleft cysts should be included in the differential diagnosis of adrenal insufficiency.

PTC gene, which is derived from the rearranged form of the ret proto-oncogene, was originally discovered in human thyroid papillary carcinomas. This gene has been thought to act as a tumorigenetic factor in thyroid carcinoma, although the action of PTC oncogene products is still unknown. To study the frequency of the PTC gene present in human thyroid carcinomas, we investigated four cell lines derived from thyroid carcinoma and 22 thyroid tumor tissue specimens. The reverse transcriptase-polymerase chain reaction (RT-PCR) method was performed to detect putative PTC mRNA. The presence of the PTC gene in genomic DNA was analyzed by Southern blot hybridization. PTC mRNA was detected by the RT-PCR method in only one papillary carcinoma cell line (TPC-1 cell). Southern gel analysis confirmed the rearrangement of the ret proto-oncogene in this cell line. In the other three cell lines and 22 tumor tissue specimens, however, neither the PTC gene or mRNA was detected. These results demonstrate that the prevalence of the PTC gene in thyroid tumor is low and may not be essential for human thyroid tumorigenesis. That our present results conflict with previous reports may be due to general differences in genetic background among races.

Parathyroid hormone (PTH) is a key factor involved in the systemic regulation of bone resorption. It is well known that a high turnover of bone occurred together with the reduced bone mass in patients with hyperparathyroidism. However, the effect of subnormal secretion of PTH on age-related bone loss has not been extensively investigated. Recently, some investigators and us have focused on the effect of suppressed PTH secretion and have demonstrated that patients with subnormal secretion of PTH preserved a relatively higher bone mineral densities than age- and sex-matched controls. We believe that these results will give a new insight into the mechanism of age-related bone loss or osteoporosis. Further studies are needed to evaluate the mechanisms of this protective effect of suppressed PTH secretion on bone mass.

We have already demonstrated the inhibitory effect of interleukin 1 on thyroglobulin gene expression. Recent availability of thyroid peroxidase cDNA has allowed us to investigate the regulation of thyroid peroxidase gene. Therefore, the regulation of thyroid peroxidase mRNA by interleukin 1 in cultured human thyrocytes was investigated. Thyrocytes dispersed from thyroid tissues from patients with Graves' disease were incubated with TSH with or withtout recombinant human interleukin 1. Unstimulated human thyrocytes did not contain any detectable thyroid peroxidase mRNA, however, TSH-stimulated thyrocytes expressed four thyroid peroxidase mRNA transcripts (4.0, 3.2, 2.1 and 1.7 kb, respectively). Both interleukin 1 α and β inhibited TSH-induced thyroid peroxidase mRNA in a dose responsive manner; 103 U/l interleukin l caused maximal suppression of TSH-induced thyroid peroxidase mRNA level to nearly basal levels. Interleukin l also inhibited cAMP analogue 8-bromo-cyclic AMP induced thyroid peroxidase mRNA level. In contrast the γ-actin mRNA hybridization signal was not altered in control or treated cells. These results demonstrate that interleukin 1 directly inhibits TSH-induced thyroid peroxidase gene expression and provide further evidence for a paracrine role of interleukin 1 as a local inhibitor of thyroid hormone synthesis.

A 40-year-old woman with adrenal insufficiency was clinically diagnosed and examined with human corticotropin releasing hormone (CRH). This patient with secondary hypo-adrenalism has shown a normal serum cortisol response to exogenous ACTH administration and has been examined with CRH, lysine-vasopressin (LVP) and insulin tolerance test (ITT), respectively. Success in secreting ACTH in response to both CRH and LVP tests, but not ITT, suggests that this disorder was possibly due to a hypothalamic CRH deficiency rather than pituitary corticotroph dysfunction. A combination of the CRH test and ITT has come to play an increasingly significant role in the diagnosis and differential diagnosis of isolated ACTH deficiency syndrome.

To examine whether suppressive doses of thyroxine have any adverse effects on bone, we evaluated various bone metabolic markers (lectin-precipitated alkaline phosphatase, osteocalcin, carboxyl-terminal region of type I collagen propeptide, tartrate-resistant alkaline phosphatase, and urinary excretion of hydroxyproline and pyridinium crosslinks), incidence of vertebral deformity, total body and regional (lumbar spine and radius) bone mineral densities (BMDs), and rates of bone loss in 24 late postmenopausal (more than 5 years after menopause) women who were treated with levothyroxine (L-T4) after total thyroidectomy for differentiated carcinoma. Depending on the clinical records, including serum TSH levels measured by immunoradiometric assay, these patients were divided into two groups. One group of patients was given suppressive doses of L-T4 (TSH0.1 mU/L, n = 12) and the other group was given nonsuppressive doses of L-T4 (TSH0.1 mU/L, n = 12). There was no difference in bone metabolic markers and incidence of vertebral deformity between the groups. In patients with TSH suppression, Z-scores of BMDs calculated from age-matched healthy women (n = 179, aged 55 to 80) were nearly in the zero range of values (0.077 at total body, 0.228 at lumbar spine, and -0.117 at trabecular region of lumbar spine). The rate of bone loss in TSH-suppressed patients (-0.849 +/- 0.605%/year) was not significantly different from that of nonsuppressed patients (-0.669 +/- 0.659). These prospective and cross-sectional data suggest that long-term levothyroxine therapy using suppressive doses has no significant adverse effects on bone.