Actin-related protein 6 facilitates proneural protein-induced gene activation for rapid neural differentiation

Neurogenesis is initiated by basic helix-loop-helix proneural proteins. Here, we show that Actin-related protein 6 (Arp6), a core component of the H2A.Z exchange complex SWR1, interacts with proneural proteins and is crucial for efficient onset of proneural protein target gene expression. Arp6 mutants exhibit reduced transcription in sensory organ precursors (SOPs) downstream of the proneural protein patterning event. This leads to retarded differentiation and division of SOPs and smaller sensory organs. These phenotypes are also observed in proneural gene hypomorphic mutants. Proneural protein expression is not reduced in Arp6 mutants. Enhanced proneural gene expression fails to rescue retarded differentiation in Arp6 mutants, suggesting that Arp6 acts downstream of or in parallel with proneural proteins. H2A.Z mutants display Arp6-like retardation in SOPs. Transcriptomic analyses demonstrate that loss of Arp6 and H2A.Z preferentially decreases expression of proneural protein-activated genes. H2A.Z enrichment in nucleosomes around the transcription start site before neurogenesis correlates highly with greater activation of proneural protein target genes by H2A.Z. We propose that upon proneural protein binding to E-box sites, H2A.Z incorporation around the transcription start site allows rapid and efficient activation of target genes, promoting rapid neural differentiation.

Proneural proteins Achaete and Scute associate with nuclear actin to promote formation of external sensory organs

Basic helix-loop-helix (bHLH) proneural proteins promote neurogenesis through transcriptional regulation. Although much is known about the tissue-specific regulation of proneural gene expression, how proneural proteins interact with transcriptional machinery to activate downstream target genes is less clear. Drosophila proneural proteins Achaete (Ac) and Scute (Sc) induce external sensory organ formation by activating neural precursor gene expression. Through co-immunoprecipitation and mass spectrometric analyses, we found that nuclear but not cytoplasmic actin associated with the Ac and Sc proteins in Drosophila S2 cells. Daughterless (Da), the common heterodimeric partner of Drosophila bHLH proteins, was observed to associate with nuclear actin through proneural proteins. A yeast two-hybrid assay revealed that the binding specificity between actin and Ac or Sc was conserved in yeast nuclei without the presence of additional Drosophila factors. We further show that actin is required in external sensory organ formation. Reduction in actin gene activity impaired proneural-protein-dependent expression of the neural precursor genes, as well as formation of neural precursors. Furthermore, increased nuclear actin levels, obtained by expression of nucleus-localized actin, elevated Ac-Da-dependent gene transcription as well as Ac-mediated external sensory organ formation. Taken together, our in vivo and in vitro observations suggest a novel link for actin in proneural-protein-mediated transcriptional activation and neural precursor differentiation.

Off-midline retroperitoneal choriocarcinoma presenting as neurologic symptoms

A 28-year-old woman suffered from frequent headaches. She had a history of a dilatation and curettage for hydatidiform moles. This admission showed markedly elevated levels of human chorionic gonadotropin (hCG) and lactate dehydrogenase. Brain MRI showed a hemorrhagic mass in the left temporal area, with rapid growth. Histology of tumors obtained from multiple areas including retroperitoneum was consistent with choriocarcinoma.

Negative-feedback regulation of proneural proteins controls the timing of neural precursor division

Neurogenesis requires precise control of cell specification and division. In Drosophila, the timing of cell division of the sensory organ precursor (SOP) is under strict temporal control. But how the timing of mitotic entry is determined remains poorly understood. Here, we present evidence that the timing of the G2-M transition is determined by when proneural proteins are degraded from SOPs. This process requires the E3 ubiquitin ligase complex, including the RING protein Sina and the adaptor Phyl. In phyl mutants, proneural proteins accumulate, causing delay or arrest in the G2-M transition. The G2-M defect in phyl mutants is rescued by reducing the ac and sc gene doses. Misexpression of phyl downregulates proneural protein levels in a sina-dependent manner. Phyl directly associates with proneural proteins to act as a bridge between proneural proteins and Sina. As phyl is a direct transcriptional target of Ac and Sc, our data suggest that, in addition to mediating cell cycle arrest, proneural protein initiates a negative-feedback regulation to time the mitotic entry of neural precursors.

Posture and performance: sitting vs. standing for security screening

A classification of the literature on the effects of workplace posture on performance of different mental tasks showed few consistent patterns. A parallel classification of the complementary effect of performance on postural variables gave similar results. Because of a lack of data for signal detection tasks, an experiment was performed using 12 experienced security operators performing an X-ray baggage-screening task with three different workplace arrangements. The current workplace, sitting on a high chair viewing a screen placed on top of the X-ray machine, was compared to a standing workplace and a conventional desk-sitting workplace. No performance effects of workplace posture were found, although the experiment was able to measure performance effects of learning and body part discomfort effects of workplace posture. There are implications for the classification of posture and performance and for the justification of ergonomics improvements based on performance increases.

Glycogen synthase kinase 3beta interacts with and phosphorylates the spindle-associated protein astrin

Emerging evidence shows that glycogen synthase kinase 3beta (GSK3beta) is involved in mitotic division and that inhibiting of GSK3beta kinase activity causes defects in spindle microtubule length and chromosome alignment. However, the purpose of GSK3beta involvement in spindle microtubule assembly and accurate chromosome segregation remains obscure. Here, we report that GSK3beta interacts with the spindle-associated protein Astrin both in vitro and in vivo. Additionally, Astrin acts as a substrate for GSK3beta and is phosphorylated at Thr-111, Thr-937 ((S/T)P motif) and Ser-974/Thr-978 ((S/T)XXX(S/T)-p motif; p is a phosphorylatable residue). Inhibition of GSK3beta impairs spindle and kinetochore accumulation of Astrin and spindle formation at mitosis, suggesting that Astrin association with the spindle microtubule and kinetochore may be dependent on phosphorylation by GSK3beta. Conversely, depletion of Astrin by small interfering RNA has no detectable influence on the localization of GSK3beta. Interestingly, in vitro assays demonstrated that Astrin enhances GSK3beta-mediated phosphorylation of other substrates. Moreover, we showed that coexpression of Astrin and GSK3beta differentially increases GSK3beta-mediated Tau phosphorylation on an unprimed site. Collectively, these data indicate that GSK3beta interacts with and phosphorylates the spindle-associated protein Astrin, resulting in targeting Astrin to the spindle microtubules and kinetochores. In turn, the GSK3beta-Astrin complex may also facilitate further physiological and pathological phosphorylation.

hNinein is required for targeting spindle-associated protein Astrin to the centrosome during the S and G2 phases

Human Ninein (hNinein) is implicated in centrosomal microtubule nucleation and microtubule anchoring in interphase cells and may act as a scaffold protein, but its direct interaction partners remain unexplored in the centrosome. In this report, we show clearly that a spindle-associated protein, Astrin, interacts and co-localizes with hNinein at the centrosome during the S and G2 phases, and this complex may dissociate in the M phase. We also demonstrate that the truncated forms of hNinein, which could interfere with gamma-tubulin and function as dominant-negative mutants, are able to affect Astrin localization to the centrosome. Moreover, siRNA-mediated knockdown of hNinein in HeLa cells causes Astrin to fail to target to the centrosome, whereas hNinein can localize at the centrosome in the absence of Astrin. In addition, reduction in hNinein protein levels causes mislocalization of Astrin with the spindle apparatus and results in the formation of an aberrant mitotic spindle. Collectively, these data suggest that hNinein is required for targeting Astrin to the centrosome during the S and G2 phases. We therefore propose a model wherein hNinein regulates the dynamic movement of Astrin throughout the cell cycle and this interaction, in turn, is required for maintenance of centrosome/spindle pole integrity.

GSKIP is homologous to the Axin GSK3beta interaction domain and functions as a negative regulator of GSK3beta

Although prominent FRAT/GBP exhibits a limited degree of homology to Axin, the binding sites on GSK3 for FRAT/GBP and Axin may overlap to prevent the effect of FRAT/GBP in stabilizing beta-catenin in the Wnt pathway. Using a yeast two-hybrid screen, we identified a novel protein, GSK3beta interaction protein (GSKIP), which binds to GSK3beta. We have defined a 25-amino acid region in the C-terminus of GSKIP that is highly similar to the GSK3beta interaction domain (GID) of Axin. Using an in vitro kinase assay, our results indicate that GSKIP is a good GSK3beta substrate, and both the full-length protein and a C-terminal fragment of GSKIP can block phosphorylation of primed and nonprimed substrates in different fashions. Similar to Axin GID(381-405) and FRATtide, synthesized GSKIPtide is also shown to compete with and/or block the phosphorylation of Axin and beta-catenin by GSK3beta. Furthermore, our data indicate that overexpression of GSKIP induces beta-catenin accumulation in the cytoplasm and nucleus as visualized by immunofluorescence. A functional assay also demonstrates that GSKIP-transfected cells have a significant effect on the transactivity of Tcf-4. Collectively, we define GSKIP as a naturally occurring protein that is homologous with the GSK3beta interaction domain of Axin and is able to negatively regulate GSK3beta of the Wnt signaling pathway.

Three-dimensional cytomorphology in fine needle aspiration biopsy of medullary thyroid carcinoma

OBJECTIVE

To elucidate three-dimensional (3-D) cytomorphology in fine needle aspiration biopsy (FNAB) of medullary thyroid carcinoma (MTC).

STUDY DESIGN

ENAB was performed on tumors from five patients with MTC. The aspirate was stained and observed under a light microscope (LM). The aspirate was also fixed, dehydrated, critical point dried, spattered with gold ions and observed with a scanning electron microscope (SEM). For transmission electron microscopy (TEM), the specimen was fixed, dehydrated, embedded in an Epon mixture, cut with an ultramicrotome, mounted on copper grids, electron doubly stained with uranium acetate and lead citrate, and observed with TEM. Findings under SEM were correlated with those under LM and TEM.

RESULTS

Under SEM, 3-D cytomorphology of MTC displayed a disorganized cellular arrangement with indistinct cell borders in three cases. The cell surface was uneven and had granular protrusions that corresponded to secretory granules observed under TEM. In one case with multiple endocrine neoplasia type IIB, there were abundant granules on the cell surface. In one case of sporadic MTC with multinucleated tumor giant cells and small cells, granular protrusions also were noted on the cell surface.

CONCLUSION

Granular protrusion was a characteristic finding in FNAB of MTC tinder SEM and might be helpful in the differential diagnosis.

Thyroidectomy or radioiodine? The value of ultrasonography and cytology in the assessment of nodular lesions in Graves' hyperthyroidism

Although diffuse toxic goiter is a classical feature of Graves' disease (GD) nodular goiters are occasionally found in some patients. The aim of the present study was to investigate the ultrasonographic and corresponding cytological manifestations in GD patients with nodular lesions to decide on a therapeutic strategy. Twenty-seven consecutive GD patients with nodular goiter were included in this study (21 women and six men, mean age 41.2 years, range 22-77 years). All underwent thyroid ultrasonography and fine-needle aspiration cytology. Of the 27 patients eight underwent surgical intervention because papillary thyroid carcinoma or follicular neoplasm was diagnosed by cytology; five of these were shown to have papillary thyroid carcinomas. Ultrasonography revealed the malignant nodules to be hypoechogenic, heterogeneous, and with ill-defined margins in four of these five thyroid cancers, whereas the remaining sonogram showed a cystic change and cauliflower-like tumor formation with microcalcification. The volume and maximal diameter of cancerous nodules were significantly larger than those of benign nodules. In conclusion our results reveal that ultrasonography and fine-needle aspiration cytology are reliable and quick methods for diagnosing nodular goiters in GD patients. If thyroid neoplasms are found ablative therapy with thyroidectomy is indicated instead of radioactive iodine.

Three-dimensional cytomorphology and its relationship with clinical stage in fine needle aspiration biopsy of papillary thyroid carcinoma

OBJECTIVE

To elucidate three-dimensional (3-D) cytomorphology and its relationship with clinical stage in fine needle aspiration biopsy (FNAB) of papillary thyroid carcinoma (PTC).

STUDY DESIGN

FNAB was performed in tumors from 34 patients with PTC. The aspirate was stained and observed under a light microscope (LM). The aspirate was also fixed, dehydrated, critical point dried, spattered with gold ions and observed with a scanning electron microscope (SEM). Findings under SEM were correlated with the presentation under LM and also with clinical stage. As a control, FNAB was also performed on a normal part of the thyroid in six patients.

RESULTS

Under SEM, normal thyroid cells appeared as round, scattered cells or sheets with a uniform honeycomb cellular arrangement. In PTC, cell sheets with uniform nuclear morphology under LM usually showed a uniform cell arrangement and with distinct cell borders under SEM. Cell sheets with nuclear pleomorphism under LM usually showed a more-disorganized arrangement and with indistinct cell borders under SEM. PTC at advanced clinical stages usually presented with a disorganized cell arrangement, indistinct cell borders and loss of microvilli.

CONCLUSION

3-D cytomorphology in FNAB of PTC was related to clinical stage and might be a prognostic factor for PTC.

Combination of color Doppler ultrasonography and ultrasound-guided fine-needle aspiration cytology for localization of parathyroid lesions

We examined the usefulness of color Doppler ultrasonography combined with ultrasound-guided fine-needle aspiration cytology (FNAC) for preoperative localization of parathyroid lesions in patients with hyperparathyroidism. Twenty-eight patients (19 men, 9 women; mean age, 56 years) with clinical and laboratory evidence of hyperparathyroidism underwent preoperative color Doppler ultrasonography and ultrasound-guided FNAC prior to surgery. On ultrasonography, the parathyroid lesions were anechoic or hypoechoic, located behind or at the margin of the thyroid gland, and mimicked blood vessels in some cases. On color Doppler ultrasound, parathyroid lesions showed little or no vascularity. They were easily differentiated from blood vessels, thus improving the safety of ultrasound-guided FNAC. Thirty-four (76%) of 45 surgically confirmed parathyroid lesions were detected with ultrasonography in 21 (75%) of the patients. There was no significant difference in the detection rates of lesions in the right upper, right lower, left upper, and left lower parathyroid glands. Eight (29%) patients had coexisting thyroid lesions. FNAC of the ultrasound-detected abnormalities provided preoperative confirmation that they were parathyroid lesions. In conclusion, our findings show that color Doppler ultrasonogrphy in combination with ultrasound-guided FNAC is useful for preoperative localization of parathyroid lesions.

Preoperative localization procedures for initial surgery in primary hyperparathyroidism

The experience of the surgeon and precise localization of abnormal parathyroid glands determine the success of surgery for primary hyperparathyroidism (HPT). In HPT patients undergoing repeat surgery, the use of localization studies improved the ability to identify the remaining abnormal parathyroid tissue. This study investigated the roles of preoperative localization techniques for initial surgery for primary HPT. From 1985 through 1997, two noninvasive localization procedures, ultrasonography (US) and 201thallium chloride-99mtechnetium pertechnetate subtraction scanning (Tl-Tc), were used prior to initial exploration for primary HPT in 76 patients. Their accuracy was determined on the basis of surgical and pathologic results. The surgical success rate was 96% (73/76). The sensitivities of US and Tl-Tc were 71% and 49%, respectively. The sensitivity of Tl-Tc was higher for the lower parathyroid glands. In 21 of 26 patients who underwent fine-needle aspiration (FNA) of the suspected enlarged parathyroid gland, the diagnosis of parathyroid adenoma was confirmed preoperatively. We conclude that the concomitant use of US and FNA is a safe and convenient method for preoperative localization of the parathyroid glands prior to initial surgical exploration in patients with primary HPT. Bilateral neck exploration by an experienced surgeon should be the routine procedure. US and Tl-Tc alone offer limited localization information, and unilateral exploration should be reserved for selected cases in which the results of these two imaging studies are consistent with one another.

Effectiveness of slow-release lanreotide, a long-acting somatostatin analogue, in the treatment of acromegaly

We evaluated the effectiveness of slow-release lanreotide, a long-acting somatostatin analogue, in the treatment of acromegaly. Eleven patients with acromegaly were recruited, six of whom had received long-term treatment with octreotide. Lanreotide 30 mg was administered by intramuscular injection every other week for 24 weeks. The frequency of injection was adjusted as clinically needed after 2 weeks. Clinical effects were evaluated, and symptoms were recorded and scored. Finger circumferences and hand volumes were measured. Serum growth hormone (GH) and insulin-like growth factor-1 (IGF-1) concentrations were determined, and an oral glucose test was done at baseline and after treatment. Symptom scores, circumferences of the fingers, hand volumes, and serum GH and IGF-1 concentrations significantly decreased during treatment. Serum GH concentrations returned to normal in five (46%) of the 11 patients, while serum IGF-1 concentrations returned to normal in three (27%). Glucose intolerance was not significantly improved at the end of treatment. Although the mean serum GH concentration was significantly decreased after treatment, it was still not suppressed by glucose. In conclusion, slow-release lanreotide, given either twice or three times a month, is effective in controlling acromegalic symptoms as well as GH and IGF-1 hypersecretion. The treatment is well tolerated and convenient for patients.

Immunoperoxidase staining in the differential diagnosis of parathyroid from thyroid origin in fine needle aspirates of suspected parathyroid lesions

OBJECTIVE

To determine whether immunoperoxidase staining could be used for differential diagnosis of parathyroid from thyroid origin in fine needle aspirates of suspected parathyroid lesions.

STUDY DESIGN

Immunoperoxidase staining of parathyroid hormone and thyroglobulin was performed on aspirated smears from 10 patients with parathyroid lesions (6 of 10 patients also associated with thyroid lesions) and 10 patients with thyroid lesions. All of them had surgical tissue proof of the diagnosis.

RESULTS

Aspirated smears of six patients with parathyroid lesions had strong to moderate staining for parathyroid hormone and negative staining for thyroglobulin. Another four patients with parathyroid lesions had equivocal staining for parathyroid hormone and negative staining for thyroglobulin. All aspirated smears from the 16 thyroid lesions had negative staining for parathyroid hormone and positive staining for thyroglobulin.

CONCLUSION

Immunoperoxidase staining of parathyroid hormone and thyroglobulin, done for each suspected parathyroid lesion, was helpful in the differential diagnosis of parathyroid vs. thyroid origin.

Clinical significance of thyrotropin-binding inhibitor immunoglobulin levels in newborns and their mothers

We investigated whether determination of thyrotropin-binding inhibitor immunoglobulin (TBII) indices in newborns with hyperthyrotropinemia on neonatal screening, or those born to mothers with autoimmune thyroid diseases, and their mothers could predict the newborns' thyroid status. We selected 195 babies born between 1988 and 1996. TBII indices in the sera of these newborns and their mothers were tested at some time from Day 1 to Day 30 after birth, and followed up after that. The subjects were divided into four groups according to the TBII index. Group 1 consisted of 17 pairs of mothers and newborns who both had serum TBII indices greater than or equal to 15%, including four transiently hyperthyroid and 13 transiently hypothyroid newborns. Group 2 comprised 166 pairs who both had a TBII index less than 15%, including one euthyroid and 165 hypothyroid newborns. Eight of the 165 warranted permanent thyroxine therapy due to athyreosis or ectopic thyroid gland. Group 3 consisted of one pair in which the newborn's serum TBII index was 15% or higher but the mother's was less than 15%: the newborn was transiently hypothyroid. Group 4 comprised 11 pairs in which the newborns' serum TBII indices were greater than or equal to 15% but the mothers' were less than 15%. These 11 newborns were all transiently hypothyroid and nine of them warranted transient thyroxine replacement therapy. The results suggest that the long-term outcome of newborns is good when TBII indices are at least 15% in the mother and child because their thyroid dysfunction seems to be related to the transient presence of the transplacental TBII from the mother. When TBII indices in both mother and child are less than 15%, the newborns warrant further investigation due to the likelihood of permanent hypothyroidism.

Relationships of orbital computed tomographic findings and activity scores to the prognosis of corticosteroid therapy in patients with Graves' ophthalmopathy

To elucidate the relationships of orbital computed tomographic findings and activity scores to the prognosis of corticosteroid therapy in patients with Graves' ophthalmopathy, 22 cases were treated with corticosteroid. Orbital computed tomographic was performed before treatment and the maximal muscle areas of rectus muscle bellies were calculated from the coronal images. Activity scores were calculated according to the recommendations of an international ad hoc committee. The clinical severity of the eye disease was based on the NOSPECS classification. Observation of the effectiveness of treatment at 6 months allowed patients to be classified into good responders or poor responders. Twelve of 22 patients (54.5%) belonged to the good responders. The total muscle areas were less in good responders. Although the total muscle areas were significantly correlated with the activity scores, no difference in the activity scores was noted between these two groups. We concluded that although activity score seems to be a predictor of initial responsiveness to anti-inflammatory drugs, the maximal muscle area is a prognostic factor of corticosteroid therapy in patients with Graves' ophthalmopathy.

Serial changes in ultrasound-guided fine needle aspiration cytology in subacute thyroiditis

OBJECTIVE

To elucidate the serial cytologic presentations of subacute thyroiditis (SAT) with ultrasound-guided fine needle aspiration (FNA).

STUDY DESIGN

Nine patients with clinically evident SAT were recruited; serial sonography and ultrasound-guided fine needle aspiration cytology were performed.

RESULTS

Sixty-one follow-up examinations were obtained in nine patients. The follow-up ranged from 1 to 5 months (mean, 3.3). Initial sonographic presentations revealed focal hypoechogenicity in three patients and multiple hypoechogenicity in six. Initial cytologic findings showed chiefly enlarged, degenerated follicular cells with prominent nucleoli, lymphocytes, colloid substance, multinucleated giant cells and neutrophils. Regression of sonographic hypoechogenicity paralleled the disappearance of acute inflammatory cells and enlarged, degenerated follicular cells and the appearance of cohesive follicles.

CONCLUSION

Improvement of SAT in sonography is fairly parallel to that in cytology even though there is a lag of improvement in the latter. Smear pattern is also related to the clinical stage of SAT. Ultrasound-guided FNA is a convenient method of obtaining sufficient and representative specimens in patients with SAT.

The genomic structure of a mouse seminal vesicle autoantigen

The genomic structure of an androgen-stimulated mouse seminal vesicle autoantigen was determined. Analysis of the nucleotide sequence established 2135 bp of the 5'-flanking region, four exons of 123, 136, 112, 227 bp, three introns of 1555, 1931, 316 bp, and 185 bp of the 3'-flanking region of this gene. Ten DNA segments, five in the 5'-flanking region, two in the first intron, and three in the second intron were identified to have more than 50% homology with the consensus sequence of the androgen response element (ARE). Two sets of adjacent DNA segments, one including -213 to -199 bp and -124 to -110 bp in the 5'-flanking region and the other including 2532 to 2546 bp and 2582 to 2596 bp in the second intron, are noticeable for their high degree of homology with ARE.

Therapeutic responses to corticosteroids in Graves' ophthalmopathy

To elucidate the therapeutic responses to corticosteroids and prognostic factors in the treatment of Graves' ophthalmopathy, 23 patients with Graves' ophthalmopathy were treated with intravenous methylprednisolone 0.5 g daily for 3 days, followed by prednisolone 40 mg daily. Dosage was reduced gradually to 10 mg daily over 4 weeks. The symptoms and signs of the eyes were recorded. Orbital computed tomography and urinary glycosaminoglycan excretion testing were performed before treatment. We observed the effectiveness of treatment at 6 months as the endpoint of this study and classified the response as good or poor. We compared the differences in parameters between these two groups. The results showed that 12 (52%) out of 23 patients had a good response, and three (25%) of those with a good response recovered completely. Corticosteroid therapy dramatically improved lacrimation, reduced soreness and congestion of the eyes and ameliorated exophthalmos, lagophthalmos and extraocular muscle movement. Four (36%) of the 11 patients with a poor response had rebound of symptoms and/or signs after the dosage of prednisolone was decreased. Those with a good response were usually younger, and enlargement of the extraocular muscle was also milder than in those with a poor response. This study demonstrated that corticosteroid therapy is effective in Graves' ophthalmopathy and that extraocular muscle size demonstrated by orbital computed tomography is a prognostic factor of therapy.

Cloning and sequencing of complete thyrotropin receptor transcripts in pretibial fibroblast culture cells

Pretibial fibroblasts are considered to be targets of autoimmune attack in pretibial myxedema. A possibility of the pathogenesis of pretibial myxedema is that T cells, reacting with thyrotropin (TSH) receptor, will be targeting to the pretibial fibroblasts where, in the presence of antigen (TSH receptor), they will secrete various cytokines and stimulate fibroblasts to secrete glycosaminoglycans. We have demonstrated that TSH and TSH receptor antibody can bind to fibroblasts and the presence of RNA encoding the extracellular domain of the TSH receptor in fibroblasts derived from skin lesions of two patients with pretibial myxedema. The present study was designed to determine whether there are complete TSH receptor transcripts in pretibial fibroblasts obtained from patients with pretibial myxedema. RNA was prepared from pretibial fibroblasts obtained from 11 patients with pretibial myxedema and from four normal subjects, then reverse-transcribed by polymerase chain reaction using three sets of primers (-11/+8 and +754/+773; +353/+373 and +1265/+1285; +1000/+1017 and +2284/+2301). The overlapped 2312 bp cDNA sequence was expected to contain the genetic sequences of the signal peptide (+1/+60), extracellular domain (+61/+1254), transmembrane domain (+1255/+2046), and cytoplasmic domain (+2047/ +2292) of the TSH receptor. The sequences were determined using dideoxy sequencing method. All of the 2312 nucleotide sequences in 15 samples were consistent with the reported TSH receptor sequence of transcripts in thyroid. These data suggest that the complete TSH receptor transcripts are very possible to be present in the fibroblasts derived from pretibial skin.

Prevalence of goiter in Taiwanese adults: a preliminary study

Although there have been many studies on the prevalence of goiters in Taiwanese school children, the goiter prevalence in Taiwanese adults is unknown. This is a preliminary study of the prevalence of goiter in adults admitted for health examinations to the National Taiwan University Hospital. The thyroid glands of 1,020 adults were palpated. Thyroid ultrasonography was also performed on all adults to confirm the palpation findings and to check goiter nodularity. Fine-needle aspiration cytology was done in nodular goiters with or without ultrasound guidance, depending on whether or not the thyroid nodules were easily located by palpation. The adult goiter prevalence was found to be 19.4% in males, 33.6% in females and 25% in total. Seven out of 1,020 adults (0.7%) had thyroid cancers diagnosed by aspiration cytology and confirmed by surgery and pathology. Of the seven adults with thyroid cancer one did not have a palpable goiter. The results show a high prevalence of goiter in these adults. Thyroid ultrasonography is useful for screening thyroid malignancy in adults. If thyroid nodules are detected, fine-needle aspiration cytology can be done with or without ultrasound guidance to confirm the malignancy.

Ultrasonographic findings of papillary thyroid carcinoma and their relation to pathologic changes

To elucidate the ultrasonographic findings in papillary thyroid carcinoma and their relation to pathologic changes, 47 patients on whom thyroid ultrasonography had been performed and whose thyroid tissues were pathologically proven to be papillary thyroid carcinoma were studied. The ultrasonographic findings were reviewed and correlated with the pathologic changes. Fifty-three out of 94 thyroid lobes had papillary carcinoma. The ultrasonographic features of the affected thyroid lobes were hypoechoic in 46, isoechoic in 6 and hyperechoic in 1. The ultrasonographic texture of all 53 lesions was heterogeneous. The margin was clear in 11 lesions and unclear in 42. Cystic degeneration was found in 15 lesions. Discrete particles representative of microcalcifications were found in 25 lesions. Halo signs were found in 7 lesions. Lymph node enlargement was detected in 4 cases. The sensitivity and specificity of each ultrasonic finding in predicting the respective pathologic feature were: unclear margin for tumor invasion, 84% and 31%; cystic degeneration for cysts, 42% and 79%; discrete particles for microcalcification, 50% and 52%; halo sign for total encapsulation, 42% and 88%; and lymph node enlargement for lymph node metastasis, 18% and 100%, respectively. These data suggest that ultrasonographic findings in papillary carcinoma were usually hypoechoic and heterogeneous. An unclear margin in sonography is fairly sensitive for the prediction of tumor invasion.

Glutathione concentration in oral cancer tissues

Glutathione (GSH) concentrations in human epidermoid carcinoma tissues were measured by high performance liquid chromatography. The mean glutathione content of 26 epidermoid carcinoma intratumor tissue specimens was 24.36 nmol/mg protein, which was significantly higher than that in adjacent non-tumor tissue parts (3.04 nmol/mg protein). The mean concentration found in normal oral mucosa was 4.80 nmol/mg protein. Tissue GSH levels were not correlated with the age of the patients or tumor size. Additionally, cellular GSH levels in nine different cell lines were found to spread over a wide range from 0.97 to 50.97 nmol/mg protein. Elevated GSH levels in cancer tissues were probably due to their abnormal proliferative activities. These results indicate that the glutathione level of oral tissues may be a useful marker for oral cancer, which is in agreement with findings from lung squamous cell carcinoma, cervical squamous cell carcinoma and other squamous cell carcinomas.

TSH and TSH receptor antibody-binding sites in fibroblasts of pretibial myxedema are related to the extracellular domain of entire TSH receptor

The role of TSH receptor antibodies in the pathogenesis of pretibial myxedema is still unclear. This study was designed to determine whether patients with pretibial myxedema had higher serum titers of TSH receptor antibodies, and whether there were TSH and TSH receptor antibody-binding sites on plasma membranes of fibroblasts derived from the skin of pretibial myxedema. If there were, were the binding sites similar to the TSH receptor? The TSH receptor antibodies were determined with radioreceptor assay in 20 normal subjects, 18 hyperthyroid Graves' disease patients without ophthalmopathy, 26 hyperthyroid Graves' disease patients with ophthalmopathy, and 11 patients with pretibial myxedema associated with Graves' ophthalmopathy. TSH and TSH receptor antibody-binding sites were studied on plasma membranes of fibroblasts cultured from the skin of pretibial myxedema with radioreceptor assay. RNA was also extracted from the fibroblasts of pretibial myxedema and reverse transcribed using random primers as the primers for cDNA synthesis. The resulting cDNAs were subjected to amplification by polymerase chain reaction with the use of a set of primers spanning the 5' region (+256/+275 and +616/+635) and the 3' region (+1819/+1838 and +2405/+2424) of the TSH receptor cDNA (+1 transcription start codon). They were further identified by Southern blot hybridization, with the probe spanning the 5' region (+272/+612) and the 3' region (+1908/+2268) of the TSH receptor cDNA (+ 1 transcription start codon), and sequencing. The results showed that patients with pretibial myxedema had higher titers of TSH receptor antibodies in the serum. TSH and TSH receptor antibody-binding sites were present on plasma membranes of fibroblasts derived from the skin of pretibial myxedema patients and related to the extracellular domain of the TSH receptor. These data suggest a common antigenic site in the skin and in the thyroid as a putative target for TSH receptor antibodies or lymphocytes of Graves' disease.

Ultrasonography and needle aspiration cytology in the diagnosis and management of parathyroid lesions

To elucidate the diagnostic value of fine needle aspiration (FNA) cytology of ultrasonically suspected parathyroid lesions, we reviewed a series of 17 cases seen over the past two years. Patients with biochemically proven primary or secondary hyperparathyroidism were examined by ultrasonography using a 7.5-MHz linear transducer. Ultrasound-guided FNA cytologic examinations with Riu's stain were performed on 13 patients who had questionable ultrasonographic patterns. The aspirates were considered adequate in nine out of 13 cases (69%). The cytologic patterns, characterized by tight cohesion of naked nuclei with indistinct cell border showing hypermonomorphism and overlapping of nuclei, were noted in adenomatous and hyperplastic lesions. There were several different findings noted in the case of parathyroid carcinoma, including loose cohesion of nuclei, larger nuclear size, and prominent anisokaryosis. One patient with secondary hyperparathyroidism who previously had a neck exploration, received an ultrasonically-guided percutaneous alcohol injection to the parathyroid lesion after cytologic verification. The result was remarkable both in volume reduction and in clinical improvement. The results suggest that ultrasound-guided FNA cytologic examination with Riu's stain is safe, simple and helpful in the localization of parathyroid lesions prior to surgery or percutaneous alcohol ablation therapy.

Ultrasound evaluation of thyroid abnormalities and volume in Chinese adults without palpable thyroid glands

Typical examination of the thyroid gland involves palpating the patient. If goiter is found, thyroid ultrasonography and/or aspiration cytology is usually performed in addition to assay of thyroid hormones and antibodies. However, palpation may not be sensitive enough to detect thyroid lesions. The purpose of this study was to evaluate the prevalence of thyroid abnormalities detected by ultrasonography in Chinese adults without palpable thyroid glands admitted for health examination. Two hundred and seventy-seven patients (aged 17 to 79 years; mean, 52 years) admitted to National Taiwan University Hospital for health examinations were included in this study. The thyroid was first palpated by a thyroidologist. Goiter was detected in 77 out of 277 patients (27.8%). Two hundred patients who had no palpable goiter underwent thyroid ultrasonography. Thyroid abnormalities were detected in 37 out of 200 patients (18.5%). These included 18 cases of thyroid cyst, 13 cases of solid nodule, and six cases of multiple nodules with ill-defined margins. Patients with thyroid abnormalities were older than those without lesions [59.3 +/- 9.2 years (mean +/- SD) vs 50.1 +/- 12.8 years, p < 0.001]. In addition, we also calculated the thyroid volumes of 163 patients who had neither palpable goiter nor lesions detected by ultrasonography. The thyroid volumes were 7.7 +/- 3.3 mL and positively correlated to the body mass index (BMI, r = 0.17, p < 0.05) and body weight (r = 0.28, p < 0.005). Males (n = 115) had larger thyroid volume than females (n = 48) (8.3 +/- 3.3 vs 6.1 +/- 2.6 mL, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Hormonal changes in elderly men with non-insulin-dependent diabetes mellitus and the hormonal relationships to abdominal adiposity

To elucidate the hormonal changes in elderly men with non-insulin-dependent diabetes mellitus (NIDDM) and the hormonal relationship to abdominal adiposity, we measured serum insulin-like growth factor 1 (IGF-1), T3, T4, TSH, testosterone, LH, and FSH levels, body mass index (BMI), skinfold thickness and waist-to-hip circumference ratio (W/H) in 40 elderly men (aged over 60 years), 20 elderly men with NIDDM (aged over 60 years) and 30 men aged 21-40 years (controls). The results showed that elderly men with and without NIDDM had lower serum T3, testosterone and IGF-1 levels and higher serum LH and FSH levels compared with controls. Elderly men with NIDDM had even lower serum testosterone levels compared with elderly men without NIDDM. Elderly men had a higher W/H ratio compared with controls. Elderly men with NIDDM had a higher W/H ratio, BMI and skinfold thickness than elderly men without NIDDM. Age was positively correlated with the W/H ratio. Serum LH and FSH levels were positively correlated with the W/H ratio, and serum IGF-1, T3 and testosterone levels were negatively correlated with W/H ratio. Age, serum IGF-1, T3, T4, TSH, LH and FSH levels were not related to BMI or skinfold thickness. Only serum testosterone levels were negatively correlated with BMI or skinfold thickness. In conclusion, elderly men with NIDDM were associated with a marked decrease in serum testosterone levels and an increase of the W/H ratio compared to other groups in addition to the age-associated decrease of serum T3, IGF-1 and testosterone levels and increase of the W/H ratio and serum LH and FSH levels.(ABSTRACT TRUNCATED AT 250 WORDS)