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T C Chang

Publications and source records attributed to T C Chang.

At least 163 records · Page 9Linked to original sources
PubMed1992

Identification of autoantigen recognized by autoimmune ophthalmopathy sera with immunoblotting correlated with orbital computed tomography.

We have demonstrated that there is an antibody related to extraocular muscle enlargement in autoimmune ophthalmopathy (Graves' ophthalmopathy, thyroid-associated correlated with orbital computed tomography (CT). This study was designed to identify the autoantigen and to determine whether there are common antigens among the extraocular muscle, the lacrimal gland, and the thyroid. We prepared a 100,000g sediment fraction of porcine extraocular muscle, lacrimal gland, thyroid, and human thyroid, followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting with sera from patients with Graves' disease, with or without ophthalmopathy, classified by symptoms and signs combined with orbital CT and normal controls. The results showed there was an approximately 55-kDa protein band which was recognized by the sera in 32.1% (9/28) of patients with autoimmune ophthalmopathy and in 47.3% (9/19) of patients with extraocular muscle enlargement demonstrated by orbital CT. It was significantly higher than the positive rates in patients without autoimmune ophthalmopathy and normal controls (15.8 and 11.1%, respectively, P < 0.025). However, there was no common antigen among the extraocular muscles, the lacrimal gland, and the thyroid. To further confirm this eye muscle-specific antigen, the approximately 55-kDa protein band was cut and solubilized from the nitrocellulose paper after SDS-PAGE, and electrophoretically transferred and used as an antigen in enzyme-linked immunosorbent assay. The absorbance was significantly higher in patients with autoimmune ophthalmopathy than patients without ophthalmopathy (P < 0.005), and normal controls (P < 0.01). Our findings suggest that an approximately 55-kDa protein may be a possible antigen in the eye muscle related to autoimmune ophthalmopathy.

Animals↗
PubMed1992

The role of estrogen response elements in expression of the Xenopus laevis vitellogenin B1 gene.

We have used site-directed mutagenesis and a homologous transient transfection system to investigate the role of the two imperfect estrogen response elements (EREs) located at -302/-334 in the 5'-flanking region of the estrogen-regulated Xenopus laevis vitellogenin B1 gene. Deletion of either ERE effectively abolishes estrogen-dependent transcription of the vitellogenin promoter. Neither replacement of the two imperfect EREs with a single consensus ERE at -334, nor insertion of one or two consensus EREs at -359, restores full estrogen responsiveness to the mutant promoter. In competition gel mobility shift assays using the DNA binding domain of the Xenopus estrogen receptor, the consensus ERE was a severalfold more effective competitor than the two imperfect B1 EREs. These data suggest that flanking DNA sequences may exert a significant effect on the activity of EREs as hormone-dependent transcription activators. When the imperfect EREs at -302/-334 were present, an additional consensus ERE at -359 exhibited synergistic activation of transcription. However, two consensus EREs located close to the TATA box showed additive, not synergistic, activation of transcription. In contrast, synergistic activation of transcription was observed in synthetic promoters containing two EREs and either the vitellogenin activator element or the NF1 or AP1 upstream activator elements.

Animals↗
PubMed1992

Choriocarcinoma of the cervix.

The incidence of primary cervical choriocarcinoma is extremely low, with only approximately 60 cases reported. We present a case of primary cervical choriocarcinoma, which was originally mis-diagnosed as a cervical pregnancy. After failure of conservative treatment with methotrexate, the patient underwent a hysterectomy, followed by chemotherapy with actinomycin-D. After twenty months of follow-up, the patient is in good condition and her serum beta-hCG levels are normal.

Adult↗
PubMed1992

Effect of estrogen on the serum level of thyroglobulin.

Thyroglobulin has been widely accepted as a useful parameter for monitoring the recurrence of differentiated thyroid carcinoma. In thyroid cell cultures, it has been reported that estrogen may stimulate the tgb gene which controls synthesis of thyroglobulin by the thyroid follicular cell. Since the serum estrogen levels of women fluctuate during the menstrual cycle, pregnancy and menopause, thyroglobulin may be unreliable in the follow-up of recurrence of differentiated thyroid carcinoma in females if it can be affected by estrogen in vivo. In order to clarify the effect of estrogen on thyroglobulin, the sera of 16 men, 42 women and 20 children were collected and divided into seven groups. Their serum estradiol and thyroglobulin levels were 17.7 +/- 1.8 pg/mL (mean +/- SEM) and 17.1 +/- 1.6 ng/mL, respectively in 20 children, 26.7 +/- 4.1 pg/mL and 12.9 +/- 1.2 ng/mL, respectively in 16 males, 151.6 +/- 20.4 pg/mL and 13.7 +/- 4.2 ng/mL, respectively in five females on the 10th to 14th days of the menstrual cycle, 16.7 +/- 1.8 pg/mL and 15.2 +/- 2.1 ng/mL, respectively in 12 postmenopausal females, 530.0 +/- 131.0 pg/mL and 14.2 +/- 1.8 ng/mL, respectively in eight pregnant women in the first trimester, 3613.9 +/- 1014.2 pg/mL and 12.0 +/- 1.6 ng/mL, respectively in seven pregnant women in the second trimester and 9246.0 +/- 694.5 pg/mL and 16.4 +/- 2.0 ng/mL, respectively in 10 pregnant women in the third trimester. The serum estradiol levels were significantly different (p less than 0.005) among these seven groups, but the serum thyroglobulin levels were not (p = 0.25). Therefore, serum thyroglobulin levels are not affected by estrogen.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Clinical experience of octreotide in the treatment of acromegaly.

To evaluate the efficacy and safety of octreotide (a somatostatin analogue) in the treatment of acromegaly, 10 patients were injected subcutaneously with octreotide, 50 micrograms, thrice daily before each meal for two days, followed by 100 micrograms thrice daily for six months. One case dropped out at the initial stage because of diarrhea, and another quit due to a lack of improvement in headaches after treatment for three months. Eight patients completed the study. The results showed that the circumference of the fourth finger and hand volume significantly decreased after treatment. Laboratory data demonstrated that serum growth hormone (GH) and somatomedin-C levels also decreased significantly. However, in six patients without a history of trans-sphenoidal adenomectomy, the serum GH and somatomedin-C levels returned to normal in only one case who had a serum GH level < 20 mU/L before treatment. In the oral glucose tolerance test, paradoxic elevation of GH subsided after treatment. In the TRH test, paradoxic elevation of GH improved after treatment. In the bromocriptine test, octreotide had a synergistic effect on the suppression of GH. All cases had the side effect of injection pain, especially at the initial stage. An increase in intestinal peristalsis and bowel movement occurred in the first week, but symptoms later subsided. Two out of these eight patients had gallbladder sludge after six months of treatment. In conclusion, octreotide is effective in the treatment of acromegaly; however, it is better used in patients who have serum GH levels < 20 mU/L, or after a trans-sphenoidal adenomectomy, and may be combined with bromocriptine to treat the patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Acromegaly↗
PubMed1992

Cardiac tamponade resulting from recurrent small-cell carcinoma of the uterine cervix temporarily responding to CE/CAV chemotherapy: report of a case.

A case of recurrent small-cell carcinoma of the uterine cervix, initially presenting with cardiac tamponade, is reported. After pericardiotomy, the patient was treated with an alternating combination of chemotherapy, which included cisplatin plus etoposide (CE) and cyclophosphamide, adriamycin plus vincristine (CAV). A partial response, with relief of a cough and diminishing metastatic pulmonary lesions, was noted from serial chest roentgenographs after the initial three cycles of chemotherapy. The patient did not receive any further treatment and the recurrent cough and dyspnea were noted two months later. In spite of the same chemotherapeutic regimen and chest radiotherapy, the patient died nine months after the initial diagnosis of metastasis.

Adult↗
PubMed1992

Prevalence of goiters in school children residing in villages where underground water is used.

A representative of Fuder village in Taichung County complained that many residents had a goiter problem, which he felt might be related to pollution from the nearby Youshi industrial area. The purpose of this study was to determine whether school children in the Fuder area have a high prevalence of goiters. We chose children of the Schichi elementary school in the Fuder area as the study population, and children of the Goumei elementary school, far from the Youshi industrial area, as controls. Both groups were from a similar geographic location (near the sea), had similar socioeconomic status, and both drank underground water. Thyroid enlargement was examined by palpation as recommended by the World Health Organization. Thyroid antibodies and hormones were determined in school children with a goiter and age-sex-matched normal control children using the particle agglutination method and radioimmunoassay, respectively. In total, 1,692 school children were examined, including 875 males and 817 females. Of these, 126 school children (7.4%) had a goiter of Grade I or above. The prevalence of goiters in Shichi and Goumei were 8.8% (59/671) and 6.6% (67/1,021), respectively. There was no significant difference between these two areas. We compared the prevalence of goiters in these two schools where underground water is drunk with another previous study in Peimen and Putai where tap water is used. There was a statistically significant difference (7.4% vs 2.6%, p < 0.0001). This suggests that the higher prevalence rate of goiters in Shichi and Goumei is related to the drinking of underground water. We recommend that the use of tap water and continued salt iodization is the way to prevent endemic goiter in these areas. A further comprehensive study is needed to determine the nature of the goitrogen in the underground drinking water of the Fuder area.

Child↗
PubMed1992

Surgical management of Graves' ophthalmopathy: stage I, inferomedial orbital decompression.

Inferomedial orbital decompression was done on 26 eyes with dysthyroid optic neuropathy (DON), seven eyes with corneal exposure which had not responded to topical lubricants, and six with disfiguring exophthalmos. Twenty-one of the 26 DON eyes (80.7%) had visual acuity improvement equal to or greater than two lines by the Snellen chart, and there was only one in all 39 eyes that dropped more than two lines. The average retinal sensitivity improvement was of borderline significance (4.25 +/- 5.73 dB), but for those 13 severely affected eyes (preoperative sensitivity loss > or = 10 dB), 11 (84.6%) of them showed significant improvement. There were 16 bilateral and seven unilateral cases. Out of all 39 eyes, the average retroplacement effect was 4.6 +/- 2.3 mm, and none of them had postoperative asymmetry greater than 2 mm by Hertel's exophthalmometry. Although the palpebral fissure height tends to remain the same after surgery, upper lid retraction is likely to be worse. The most frequent sequela was diplopia, which tended to occur in more severely myopathic eyes regardless of the surgical approach used. Although a staged approach is mandatory in surgical treatment of this disorder, individualization of surgical goals and intraoperative titration of the retroplacement effect are of equal importance for optimal results.

Adult↗
PubMed1992

Prediction of the small for gestational age infant: which ultrasonic measurement is best?

OBJECTIVE: To determine the most appropriate ultrasonic measurement for the prediction of a small for gestational age (SGA) infant. DATA SOURCES: A literature search of all English language journals over the last 15 years was undertaken. One hundred seventeen articles on the use of morphometric and Doppler ultrasonic measurements in the diagnosis of SGA were reviewed. METHODS OF STUDY SELECTION: Studies were included if antenatal and postnatal criteria for diagnosis were clearly defined and data for SGA and normal fetuses were reported, allowing the construction of a 2 x 2 table. DATA EXTRACTION AND SYNTHESIS: Studies with the same criteria were grouped according to whether the population was high or low risk. The sensitivity, odds ratio (OR), and false-positive rate were calculated for each study; summary statistics were then calculated for each ultrasonic measurement provided the individual sensitivities, ORs, and false-positive rates were not significantly different (P > .01). CONCLUSIONS: In high-risk subjects, abdominal circumference below the tenth percentile had the highest common sensitivity, and estimated fetal weight below the tenth percentile had the highest common OR. In studies in which morphometric and Doppler ultrasonic measurements were compared in the same subjects, the Doppler ORs tended to be lower than the ORs for morphometric measurements. In low-risk subjects, much lower ORs were found for all ultrasonic measurements. The heterogeneous nature of the studies reviewed may have contributed to the different results within each group.

False Positive Reactions↗
PubMed1991

Blood content in guinea-pig tissues: correction for the study of drug tissue distribution.

The blood content in different organs or tissues of guinea-pigs was determined by means of [125I]bovine serum albumin. The blood distribution expressed as percentage of total body blood for various organs or tissues ranged from 0.35 (adipose) to 17.5 (muscle)%. The blood content in tissue preparations expressed as the blood background correction factor, F (ml blood/g wet tissue) depended on the extent of bleeding during experiment; that factor can cause a considerable difference in the results of a tissue distribution study of a drug. Blood content was high in the lung (0.36 ml/g), heart, liver, kidney and spleen, but low in adipose and brain tissues (0.021 ml/g). The distribution of valproic acid in various tissues of guinea-pigs after intravenous injection was determined from the homogenates of isolated organs. The results showed that blood contamination can greatly alter the data of tissue distribution of a drug to as much as 25%. This study proposed a maximum (non-bled) and a minimum (extreme-bled) blood background correction factor for respective tissues of guinea-pigs, as well as equations for correcting the blood contamination in tissue during the drug distribution study. The results suggest that to obtain an exact analysis of drug concentrations in specific tissues, a correction for the blood of that specific tissue is necessary.

Animals↗
PubMed1991

Higher prevalence of goiter in endemic area of blackfoot disease of Taiwan.

Blackfoot disease is an endemic peripheral vascular disorder which is confined to a limited land area on the southwest coast of Taiwan. It has long been related to the consumption of high levels of arsenic found in the artesian well water. Humic substances have also been extracted from the well water and have been reported as a possible source of environmental goitrogen. The purpose of this study was to examine whether the prevalence of goiter is increased in the blackfoot disease-endemic area. This study covered all the children in the elementary schools of Putai and Peimen. They were divided into two groups according to the location of schools in the endemic area or non-endemic area of blackfoot disease. Thyroid enlargement was examined by palpation as recommended by the World Health Organization. Thyroid antibodies and hormones were determined in school children with a goiter and age-sex-matched normal control children using particle agglutination methods and radioimmunoassays, respectively. Aspiration cytology was done in cases with a nodular goiter. In total 4,567 school children were examined, including 2,306 males and 2,261 females. One hundred and twenty school children (2.63%) had a goiter of grade I or above. The prevalence of goiters in school children from the endemic area was higher than that from the non-endemic area (3.44 vs 2.08%, p less than 0.01). The prevalence of goiters in females from the endemic area was higher than that from the non-endemic area (4.65 vs 2.69%, p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Biomarkers↗
PubMed1991

Coefficient of variation of nuclear diameters as a prognostic factor in papillary thyroid carcinoma.

To determine whether the coefficient of variation (CV) of nuclear diameters can be used as a prognostic factor in papillary thyroid carcinoma, we reviewed fine needle aspiration smears with Riu's stain from 55 operated-on and pathologically verified cases with a median follow-up of 6.5 years. For each case we measured the nuclear diameters of 100 cancer cells by ocular micrometry and calculated the CV of the nuclear diameters. Then we correlated the CV with the clinical stage, recurrence and death. There was a positive correlation between the CV of the nuclear diameters and the clinical stage (r = .59, P less than .0001). Recurrent cases (n = 10) had a higher CV than did those without recurrence (n = 45) (18.04 +/- 4.1% [mean +/- SD] versus 13.2 +/- 2.7%, P less than .0005). All recurrent cases had a CV greater than 13%. The cases in which death occurred (n = 5) had a higher CV than did those with survival (n = 50) (20.1 +/- 4.9% versus 13.5 +/- 2.7%, P less than .0005). All cases in which death occurred had a CV greater than 15%. The extent of variation of nuclear diameters was one of the factors influencing prognosis in papillary thyroid carcinoma. It offers a prognostic adjunct to standard clinical and histologic analysis.

Adult↗
PubMed1991

Recombinant DNA produced somatropin in the treatment of prepubertal growth hormone deficient children.

The safety and efficacy of recombinant DNA produced human growth hormone in the treatment of growth failure in prepubertal children with idiopathic or organic deficiency of pituitary GH has been assessed. Five patients entered this clinical trial. They had never been treated with hGH, anabolic steroids or any medicine that affected GH and all of them were healthy without any chronic disease; except patient 1, who took a surgical operation for cerebellar astrocytoma at the age of 3. Each patient was treated with subcutaneous injection of recombinant somatropin (SAIZEN) at a dosage of 0.2 IU/Kg +/- 10% three times per week in the evening for 1 year. Typical catch up growth was observed. The height increased by between 6.3 and 15.1 cm and their mean growth velocity of 3.7 cm/yr prior to therapy increased to 11.1 cm/yr during one year of treatment. The annual change in bone age during the treatment with SAIZEN was 2.0 +/- 0.6 years in four patients, except patient 2 who showed different bone age (right hand 3.5 years, left hand 6.0 years). Anti-hGH antibodies were observed in patient 1, but the binding capacity was low (1:10), and no clinical symptoms or growth attenuation occurred. No side effects or laboratory abnormalities were noted throughout the clinical trial. In conclusion, recombinant somatropin has a growth promoting effect and low immunogenicity, and it is shown to be safe and effective during the first year of therapy in children with GH deficiency.

Body Height↗
PubMed1990

An NF1-related vitellogenin activator element mediates transcription from the estrogen-regulated Xenopus laevis vitellogenin promoter.

We have used a homologous transfection system employing cell lines derived from Xenopus hepatocytes and fibroblasts and cloned Xenopus estrogen receptor to identify a DNA sequence essential for efficient transcription of the powerful estrogen-regulated Xenopus laevis vitellogenin B1 promoter. Although deletion of the CAAT box, the conserved nematode box, and several other sequences had little effect on vitellogenin promoter activity, deletion or mutation of a short sequence related to the NF1 transcription activator reduced estrogen-dependent transcription 10-20-fold in both cell lines. The activity of the vitellogenin activator (VA) element, which is located at positions -48 to -41, is strongly position dependent. Insertion of even five copies of the VA element at -445 does not restore activity to a VA deletion, while insertion of a single VA element at -62 largely restores promoter activity. The VA element is not liver-specific, since VA deletions, mutations, and insertions elicited similar effects on vitellogenin promoter activity in the cell lines derived from hepatocytes and fibroblasts. Gel mobility shift assays using nuclear extracts from the Xenopus hepatocyte cell line demonstrate the presence of a protein which binds with high affinity and specificity to the VA sequence. The NF1 consensus sequence, but not a functional AP1 consensus sequence, which actually exhibits higher homology to the VA element than the NF1 sequence, competes for binding to the VA element. In transfections using simplified promoters in which single copies of the VA region or NF1 sequence are linked to a TATA box, the VA region, which does not contain a palindrome, is 2.4-fold more active than the consensus NF1 palindrome. The VA-binding protein therefore appears to be related to, but not identical to, the NF1 transcription activator.

Animals↗
PubMed1990

Absence of growth-hormone receptor in hepatocellular carcinoma and cirrhotic liver.

Hepatocellular carcinoma is a hormone-sensitive tumor. It has been reported that thyroxine and prolactin significantly stimulated hepatoma growth, whereas growth hormone failed to do so. To learn whether the growth hormone receptor is present in human hepatocellular carcinoma, we used radioreceptor assays in samples of human hepatocellular carcinoma. The liver tissues adjacent to hepatocellular carcinoma (mostly cirrhotic) and control liver tissues (taken during various surgical procedures) were also studied. The study results showed that the affinity constant and capacity of high-affinity growth hormone receptor in normal liver tissues were 6.6 +/- 2.0 x 10(10) mol/L-1 (mean +/- SE, n = 7) and 20.7 +/- 11.5 fmol/mg protein, respectively. The affinity constant and capacity of low-affinity growth hormone receptor in normal liver tissues were 8.9 +/- 3.3 x 10(9) mol/L-1 and 64.7 +/- 32.1 fmol/mg protein, respectively. The absence of growth hormone receptor in human hepatocellular carcinoma and cirrhotic liver samples may explain the absence of growth hormone in the stimulation of hepatoma growth and the decrease of somatomedin levels in cirrhosis.

Adult↗
PubMed1990

Correlation of orbital computed tomography and antibodies in patients with hyperthyroid Graves' disease.

The purpose of this study was to elucidate the incidence of orbital changes in computed tomography, and the relationships of orbital changes with eye-muscle antibody (EMAb), thyrotrophin-binding inhibitor immunoglobulin (TBII), antithyroglobulin antibody (TgAb) and anti-thyroid microsomal antibody (MsAb), in 55 consecutive patients with hyperthyroid Graves' disease. EMAb was demonstrated by an immunoperoxidase technique. The results showed that the prevalence of orbital fat increase, extraocular muscle enlargement, lacrimal gland enlargement and optic nerve swelling were 54.5, 41.8, 21.8 and 16.5% respectively. There were 32.7% of patients without any orbital changes. The patients with extraocular muscle enlargement, lacrimal gland enlargement and optic nerve swelling had higher titres of EMAb than the patients without these orbital changes. The patients with lacrimal gland enlargement had a lower TBII index than those without. There was no difference in TgAb or MsAb between the patients with extraocular muscle enlargement, lacrimal gland enlargement, optic nerve swelling or orbital fat increase and those patients without these orbital changes. The patients with extraocular muscle enlargement, optic nerve swelling and orbital fat increase had a higher degree of exophthalmos than the patients without these orbital changes. EMAb was negatively correlated with TBII. However, there was no correlation between EMAb and TgAb or MsAb. The degree of exophthalmos was positively correlated with EMAb and negatively correlated with age. There was no correlation between exophthalmos and TBII, TgAb or MsAb. In conclusion, although the pathogenesis of orbital changes and hyperthyroidism is different, a close link between these two entities is suggested by the high incidence of orbital changes in hyperthyroid Graves' disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Ultrasonographic findings in relation to ease of aspiration and fluid characteristics in thyroid cyst.

Sixty-six thyroid cysts in 65 patients were studied prospectively using the aspiration method and ultrasonography. The major post-aspiration ultrasonographic change was thyroid tissue enlargement in 95% (62/65) in addition to the decreased size of the thyroid cysts in all. More than double increments of thyroid tissue could be noted in 54% (35/65) of the patients. The color of cystic fluid was related to the duration of the cyst and internal echogenicity (p less than 0.01 and p less than 0.02, respectively). Acute hemorrhage usually had a dark-reddish fluid and an increased echogenicity. The viscosity of the cystic fluid could influence the success rate of aspiration (p less than 0.05). The effect of aspiration was not good if the thyroid cyst had thick gelatinous fluid. Because a cystic goiter may be associated with malignancy, aspiration biopsy should be performed after the fluid is drawn especially if the thyroid tissue is expanded. If there is no evidence of malignancy, aspiration can be tried more than once if the cyst reappears.

Adolescent↗