A central scar in hepatic focal nodular hyperplasia detected on liver SPECT imaging.
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Publications and source records attributed to P W Wang.
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A deletion of the long arm of chromosome 20, del(20q), is a recurring abnormality in malignant myeloid diseases. In previous studies, we delineated a commonly deleted segment (CDS) of 5 Mb within band 20q12 flanked by D20S206 (proximal) and D20S481 (distal). We have generated a detailed physical map of P1 artificial chromosome (PAC) clones of this interval as well as a transcriptional map. The contig consists of 81 clones to which 152 markers (27 genes, 45 unique expressed sequence tags (ESTs) or UniGenes, 24 polymorphisms, and 56 sequence-tagged sites) have been mapped. Using PAC clones for fluorescence in situ hybridization analysis of myeloid leukemia cells with reciprocal translocations of 20q, or unbalanced rearrangements leading to loss of 20q, we have narrowed the CDS to an approximately 250-kb interval encompassing two overlapping PACs, P201E16 and P29M7 (between EST AA368224 and D20S481). This interval is gene-rich and contains 5 characterized genes, 4 UniGenes, and 9 single ESTs. The development of a transcriptional map and the identification of the smallest CDS will facilitate the molecular cloning of a myeloid leukemia suppressor gene on 20q.
Psychosis is a cardinal symptom of schizophrenia, but also occurs in other psychiatric conditions, including mood disorders. In many instances, brain abnormalities in psychotic and mood disorders appear to be on a spectrum, with the most marked changes in schizophrenia, followed by psychotic mood disorders, followed by nonpsychotic mood disorders. Such observations are consistent with the notion that mood disorders and schizophrenia represent a continuum of disease. However, in some instances, cerebral changes with psychosis may be qualitatively different, rather than merely more severe than those seen in mood disorders, more consistent with the theory that they are discrete entities. We review brain imaging studies that have advanced our knowledge of psychosis in mood disorders, with respect to the continuum versus discrete entity hypotheses.
Two cases of non-familial, late onset (50 and 62-years-old) hyalinosis cutis et mucosae were studied and compared with classical early onset cases. Late onset cases showed essentially the same histological and ultrastructural features described for early onset cases. The late onset variety should be distinguished from other diseases; they resemble systemic amyloidosis and sometimes the adult form of colloid milium.
UNLABELLED: The purpose of this study was to determine whether gallbladder visualization can help exclude biliary atresia in hepatobiliary scintigraphic studies of infants with persistent jaundice. METHODS: One hundred fifty-two infants with persistent jaundice (49 patients with a final diagnosis of biliary atresia and 103 with biliary patency) were studied using both hepatobiliary scintigraphy and abdominal sonography. Food was withheld for 4 h before the examination, and the infants were fed nothing but glucose until 6 h after the initial injection of (99m)Tc-disofenin or until the gallbladder was seen. If the gallbladder was seen, the infants were fed milk, and imaging was continued to observe gallbladder contractility. RESULTS: In none of the 49 patients with biliary atresia could the gallbladder be seen with hepatobiliary scintigraphy, but abdominal sonography revealed 9 normal-sized gallbladders. Of the 103 patients with biliary patency, hepatobiliary scintigraphy detected the gallbladder more frequently (74%, 76/103) than did abdominal sonography (63%, 65/103). All visualized gallbladders contracted after the infants were fed milk. If we include visualization of both the gallbladder and bowel radioactivity as criteria, the specificity of biliary atresia on hepatobiliary scintigraphy increases to 86% (89/103). CONCLUSION: Gallbladders were usually visible on hepatobiliary scintigraphy of fasting patients with biliary patency. A functioning gallbladder, with or without visualization of bowel radioactivity, indicated biliary patency.
Members of the MAF family of basic region/leucine zipper transcription factors can affect transcription in either a positive or a negative fashion, depending on their partner protein(s) and the context of the target promoter. The KRML (MAFB) transcriptional regulator plays a pivotal role in regulating lineage-specific hematopoiesis by repressing ETS1-mediated transcription of erythroid-specific genes in myeloid cells. In previous studies, we mapped the human KRML gene within a genomic contig on human chromosome 20, bands q11.2-q13.1. We have isolated the human cDNA containing the full-length predicted open reading frame (ORF). Multiple KRML transcripts of approximately 1.8 and approximately 3 kb, which differ in the length of the 3' untranslated region, are ubiquitously expressed in hematopoietic tissues and encode a protein with 323 amino acids (MW 35,832). The protein has 84% identity and 92% similarity to the murine protein. The ORF of the human KRML gene contains no introns, and the gene spans approximately 3 kb. KRML maps within the smallest commonly deleted segment in malignant myeloid disorders characterized by a deletion of 20q; however, we detected no mutations of KRML in leukemia cells with loss of 20q. Thus, KRML is unlikely to be involved in the pathogenesis of malignant myeloid disorders characterized by abnormalities of chromosome 20.
The objective of this study was to find the factors responsible for hypothyroidism after subtotal thyroidectomy for Graves' disease. Two hundred five patients who were operated on from July 1989 to December 1997 were studied. The mean age of patients was 33.4+/-11.0 (mean +/- SD) years, and 175 (85.4%) were female. Patients were prepared with an antithyroid drug and Lugol's solution preoperatively. Triiodothyronine (T3), thyroxine (T4), thyrotropin (TSH), thyrotropin-binding immunoglobulins (TBII) antimicrosomal antibodies (AMA = 100x 4(M-1)), and antithyroglobulin antibodies (ATA = 100x4(T-1)) were measured 1 week before patients were operated on. Operations were performed according to the standard procedure with 2.5x1x1 cm of thyroid tissue remaining on each side before approximating the thyroid capsule and pretracheal fascia. Hypothyroidism was defined by patients with overt hypothyroidism in laboratory data, and or with T4 to maintain T3 and T4. Two hundred two patients were checked 3 months after being operated on. Latent hyperthyroidism was found in 22, euthyroidism in 55, latent hypothyroidism in 91, hypothyroidism in 34 (16.8%) and none were in overt hyperthyroidism. After a follow-up period of 26.9+/-15 (mean +/- SD) months, 199 patients were reevaluated. Overt hyperthyroidism was found in 2 patients, latent hyperthyroidism in 12, euthyroidism in 97, latent hypothyroidism in 72, and hypothyroidism in 16 (8%). Factors having possible effects on hypothyroidism after longterm follow-up were analyzed. Patient's age, gender, body surface, premedicative T3 and T4, preoperative ATA, and TBII, and the weight of removed thyroid had no effect on the occurrence of hypothyroidism. Preoperative AMA levels, and finding more than 10 lymphoid infiltrations per 10 low-power fields (x40) were significantly different between the hypothyroid and nonhypothyroid groups. A high level of preoperative AMA was the only factor independently causing overt hypothyroidism in the follow-up period. Patients with high preoperative AMA levels have a higher risk of hypothyroidism if only 2.5x1x1 cm remnants are left on each side.
For patients with differentiated thyroid carcinoma, the appropriate degree of TSH suppression by levothyroxine (L-T4) is still unknown. To find the target level of TSH suppression, we analyzed the relationship between the degree of TSH suppression determined by third generation assay and thyroglobulin (Tg) response during the titration of the dosage of L-T4. Ninety-two patients with differentiated thyroid carcinoma (19 males and 73 females; age, 40.5+/-13.5, mean +/- SD) were included. All of the recruited patients had near-total thyroidectomy, 30-150 mCi 131I thyroid ablation, and negative Tg autoantibodies. They were classified into 3 groups. Group A was composed of 25 patients with local or distant relapse. Group B was composed of 12 patients without clinically detectable relapse, but Tg levels either above 2 ng/mL under L-T4 suppression or above 3 ng/mL off L-T4 therapy. Group C included 55 patients who had no active disease and Tg levels below 2 and 3 ng/mL during and off L-T4 suppression, respectively. Serum TSH and Tg were measured simultaneously at the end of 8-12 weeks of a certain dose of L-T4 therapy during dosage titration and also after withdrawal of L-T4 for 4-6 weeks for the total body scan. Wilcoxon signed ranks test was used to compare paired samples of Tg, and Spearman rank correlation was used to determine the correlation of relative changes in TSH to changes in Tg calculated by individual. The results showed that 1) Tg levels were significantly higher during the period off L-T4 therapy than on L-T4, therapy in all 3 groups (P < 0.01); 2) during L-T4, therapy, within the same treatment course, mean Tg levels were higher when TSH levels were normal than when TSH levels were suppressed, statistically significant in group A (P = 0.001), nonsignificant in group B (P = 0.09), and nonsignificant in group C (P = 0.30); and 3) when TSH was suppressed below normal, there was no correlation between the relative changes in TSH and Tg by individual in all 3 groups (P > 0.05). The data suggest a stratified postoperative thyroid hormone management of patients with differentiated thyroid carcinoma. TSH should be lowered to below normal in patients with active disease. If patients are clinically disease free with Tg levels below 2 ng/mL, TSH can be kept within the normal range. For the most controversial group B patients, it is recommended that the TSH be suppressed and be closely followed up.
The transition from metaphase to anaphase and exit from mitosis involve the degradation of active cyclin B-CDC2 complexes by ubiquitin-mediated proteolysis. The anaphase-promoting complex (APC) catalyzes the formation of cyclin B-ubiquitin conjugates, thereby targeting cyclin B for degradation. The APC is composed of eight proteins, including four members of a family characterized by multiple tetratricopeptide repeats (TPR). We mapped two overlapping expressed sequence tag clones within a genomic contig on human chromosome 5, band q31. A search revealed high homology to Saccharomyces cerevisiae CDC23, a TPR protein component of the APC. We have isolated the human CDC23 cDNA containing the full-length predicted open reading frame. The approximately 3.3-kb message is ubiquitously expressed and encodes a protein with 591 amino acids (MW = 68,293 Da) and 9 TPR units. The protein has 30% identity and 51% similarity to the S. cerevisiae protein. The human CDC23 gene contains 16 exons and spans approximately 31 kb. CDC23 maps within the smallest commonly deleted segment in myeloid leukemias characterized by a deletion of 5q; however, we detected no mutations of CDC23 in leukemia cells with loss of 5q. Thus, CDC23 is unlikely to be involved in the pathogenesis of myeloid leukemias characterized by abnormalities of chromosome 5.
The present study was aimed at investigating the prevalence of thyroid dysfunction in the elderly, aged 65 years or older, in a community of southern Taiwan. By using the records of the local household registry, a sampling frame for the elderly population was constructed, and a sample of 1,400 subjects was drawn by simple random sampling. After the exclusion of nonresponse subjects, 917 subjects aged between 65 and 88 years (mean 71.9) were included in our survey. The serum thyrotropin levels of these participants were measured by monoclonal antibodies TSH immunoradiometric assays. A normal range, 0.45-4.65 microU/ml, was determined from the middle 95% of the TSH distribution of 140 'disease-free' subjects. By reference to the normal range, 23 (2.51%) participants had high (> 4.65 microU/ml), and 41 (4.47%) had low (< 0.46 microU/ml) TSH levels. The overall prevalence of thyroid dysfunction in the sample was 6.98%. Of the 23 participants with high TSH levels, 8 (34.8%) had low free T4 values (< 1.21 ng/dl), so-called overt hypothyroidism, and of the 41 participants with low TSH levels, only 1 (2.4%) had high T3 values, so-called T3 thyrotoxicosis. Antithyroid antibodies were found in 56.5% of those with high TSH levels but only 12.2% of those with low TSH levels (odds ratio = 8.53, 95% confidence limits = 2.55-28.50, p < 0.001). This result indicates that autoimmune disease is still the major cause of hypothyroidism in aged people. However, the prevalence of subclinical hyperthyroidism is higher than that of subclinical hypothyroidism and it might relate to nonautoimmune factors.
This study was performed in 36 healthy volunteers to define the relationship between plasma concentrations of partially oxidized low density lipoprotein (poxLDL), plasma glucose and insulin responses to oral glucose, and steady-state plasma glucose (SSPG) concentrations after a 180-minute infusion of somatostatin, insulin, and glucose. The concentration of poxLDL was estimated by determining the amount of conjugated dienes formed during in vitro LDL oxidation in the presence or absence of alanine. Under these conditions, the greater the in vitro antioxidant effect of alanine, the lower the amount of poxLDL that was present in plasma. The results demonstrated that plasma poxLDL concentration was significantly correlated with plasma glucose (r=.53, P<.001) and insulin (r=.43, P<.01) responses, SSPG concentrations (r=.53, P<.001), and plasma triglyceride (r=.42, P<.01) and HDL cholesterol (r=-.50, P<.002) concentrations. Furthermore, these relationships persisted when the data were corrected for differences in age, sex, body mass index, and the ratio of waist to hip girth. Of note, there was no correlation between poxLDL and LDL cholesterol concentration. When SSPG was entered along with age, sex, body mass index, and waist-to-hip ratio in a multiple regression model, SSPG alone was a significant prediction of poxLDL (r-=.37, P<.02). The addition of plasma glucose and insulin responses and triglyceride and HDL cholesterol concentrations increased the r2 to only .47. These results show that the amount of poxLDL in plasma is significantly correlated with insulin resistance (ie, SSPG) and its metabolic consequences.
The aim of this study was to test the hypothesis that plasma leptin concentrations contributed to the pathophysiology of NIDDM by decreasing both insulin-mediated glucose disposal and glucose-stimulated insulin secretion. The study was performed in 60 women with normal oral glucose tolerance. Differences in insulin-mediated glucose disposal were determined by comparing the steady-state plasma glucose (SSPG) concentrations attained at the end of a 180-min constant infusion of somatostatin, glucose, and insulin, while comparisons of glucose-stimulated insulin secretion were based on the incremental increase in insulin concentration 30 min after an oral glucose challenge (deltaIns) as compared with the fasting value. The results showed that the higher the fasting plasma leptin concentration, the greater the degree of insulin resistance (r = 0.47, P < 0.01). Furthermore, multiple regression analysis indicated that the relationship between leptin and SSPG was independent of age and degree of obesity as estimated by BMI. However, since the total integrated plasma insulin response was highly correlated with both SSPG (r = 0.80, P < 0.001) and leptin (r = 0.55, P < 0.01), multiple regression analysis was repeated, adding total insulin response to the model. When this was done, the significant relationship between leptin and SSPG disappeared, whereas both BMI (P < 0.03) and insulin response (P < 0.001) were correlated with SSPG. A significant relationship between leptin and deltaIns was seen, but it was a positive one (r = 0.31, P < 0.02), not a negative one as would be expected if circulating levels of leptin inhibited glucose-stimulated insulin secretion. Furthermore, multiple regression analysis could only confirm an independent relationship between deltaIns and SSPG, but not between deltaIns and leptin. The results of these studies do not support the view that circulating leptin has a primary effect on either insulin action or secretion in normal female volunteers. It seems more likely that chronic hyperinsulinemia in insulin-resistant individuals acts to increase adipose tissue leptin synthesis and secretion, leading to higher ambient leptin concentrations.
A deletion of the long arm of chromosome 20 [del(20q)] is a recurring abnormality in a wide spectrum of myeloid disorders. Loss of genetic material from 20q may confer a proliferative advantage to myeloid cells, possibly through loss of function of a tumor suppressor gene. Previously, we analyzed leukemia cells from 19 patients with a del(20q) by fluorescence in situ hybridization (FISH) and identified a segment that was deleted in 95% of all patients examined. The deleted interval extended from 20q11.2 to q12, spanned approximately 13 Mb, and was flanked proximally by RPN2 and distally by D20S17. To narrow the commonly deleted segment and facilitate the identification of candidate genes, we have employed molecular approaches in combination with FISH. By using 21 microsatellite markers positioned in a recently generated physical map of 20q, we performed allele loss studies in myeloid leukemia cells from 23 patients with a del(20q). The results of these studies allowed us to delineate a new proximal border, flanked by marker D20S206. By FISH analysis of additional leukemia samples from patients with a del(20q), we have also delineated a new distal boundary between markers D20S119 and UT654. As a result of the redesignation of both the proximal and distal boundaries, we have successfully narrowed the commonly deleted segment within 20q12 to a region spanning approximately 8 Mb. Identification of the smallest deleted segment will facilitate the eventual cloning of a candidate myeloid tumor suppressor gene.
The outcome of Graves' disease after treatment with antithyroid drugs (ATDs) varies widely among countries, and large-scale studies in Asia are rare. We investigated the associations of various clinical and laboratory features with the outcome of ATD therapy for Graves' disease in Taiwan. A total of 210 patients (177 women, 33 men; mean +/- SD age, 41.7 +/- 15.1 yr) treated with ATD in Taiwan were included. ATD therapy started with methimazole 30 mg daily or propylthiouracil 300 mg daily and was continued until a euthyroid state was achieved. Afterwards, 154 patients received a maintenance dose of ATD alone, while 56 patients received a combination of an ATD and thyroxine (L-T4). Patients were considered to be in remission if they remained in a euthyroid state for more than 2 years after drug withdrawal. The mean follow-up periods were 45.0 +/- 20.9 months for patients with remission and 30.4 +/- 19.8 months for those with relapse. Relapse occurred in 126 (60%) patients during the follow-up period, within 3 months after drug withdrawal in 47 (37%), and within 6 months in 60 (46%). The relapse rate was 100% among patients with two or more previous relapses. Patients with a second occurrence had a higher relapse rate than those with a first occurrence (84% vs 43%). Past history of recurrence, goiter size, thyroid-stimulating hormone level and thyrotropin-binding inhibition immunoglobulin activity at the end of ATD treatment were independently associated with relapse. Prolonged duration of treatment did not yield better results in patients with larger goiters or a history of recurrence, or both. Combination therapy with L-T4 yielded similar results to those achieved with ATD treatment alone. In conclusion, the relapse rate of Graves' disease after ATD treatment in Taiwanese patients was high, especially in those with a history of recurrence. The treatment duration and drug regimen did not affect the outcome.
Loss of a whole chromosome 5 or a deletion of the long arm, del(5q), is a recurring abnormality in malignant myeloid diseases. In previous studies, we delineated a commonly deleted segment of approximately 4 Mb within band 5q31 that was flanked by IL9 on the proximal side and D5S166 on the distal side. We have generated a physical map of P1 (PAC), bacterial (BAC), and yeast artificial chromosome (YAC) clones of this interval. The contig consists of 108 clones (78 PACs, 2 BACs, and 28 YACs) to which 125 markers (5 genes, 11 expressed sequence tags, 12 polymorphisms, and 97 sequence-tagged sites) have been mapped. Using PAC clones for fluorescence in situ hybridization analysis of leukemia cells with a del(5q), we have narrowed the commonly deleted segment to 1-1.5 Mb between D5S479 and D5S500. To search for allele loss, we used 7 microsatellite markers within and flanking the commonly deleted segment to examine leukemia cells from 28 patients with loss of 5q, and 14 patients without cytogenetically detectable loss of 5q. In the first group of patients, we detected hemizygous deletions, consistent with the cytogenetically visible loss; no homozygous deletions were detected. No allele loss was detected in patients without abnormalities of chromosome 5, suggesting that allele loss on 5q is the result of visible chromosomal abnormalities. The development of a stable PAC contig and the identification of the smallest commonly deleted segment will facilitate the molecular cloning of a myeloid leukemia suppressor gene on 5q.
This study examined bone density among postmenopausal Buddhist nuns and female religious followers of Buddhism in southern Taiwan and related the measurements to subjects characteristics including age, body mass, physical activity, nutrient intake, and vegetarian practice. A total of 258 postmenopausal Taiwanese vegetarian women participated in the study. Lumbar spine and femoral neck bone mineral density (BMD) were measured using dual-photon absorptimetry. BMD measurements were analyzed first as quantitative outcomes in multiple regression analyses and next as indicators of osteopenia status in logistic regression analyses. Among the independent variables examined, age inversely and body mass index positively correlated with both the spine and femoral neck BMD measurements. They were also significant predictors of the osteopenia status. Energy intake from protein was a significant correlate of lumbar spine BMD only. Other nutrients, including calcium and energy intake from nonprotein sources, did not correlate significantly with the two bone density parameters. Long-term practitioners of vegan vegetarian were found to be at a higher risk of exceeding lumbar spine fracture threshold (adjusted odds ratio = 2.48, 95% confidence interval = 1.03-5.96) and of being classified as having osteopenia of the femoral neck (3.94, 1.21-12.82). Identification of effective nutrition supplements may be necessary to improve BMD levels and to reduce the risk of osteoporosis among long-term female vegetarians.
Plasma glucose, insulin, and proinsulin concentrations were measured before and after an oral glucose challenge in 57 nondiabetic individuals. In addition, insulin-mediated glucose disposal was estimated by determining the steady state plasma glucose (SSPG) concentration after a 180-min iv infusion of somatostatin, insulin, and glucose. The plasma glucose concentration after oral glucose administration was used to divide the population into those with normal (n = 36) or impaired glucose tolerance (IGT; n = 21), and the 36 normal glucose-tolerant individuals were further subdivided into an insulin-sensitive (SSPG, < 9.0 mmol/L; n = 15) and an insulin-resistant (SSPG, > 10 mmol/L; n = 21) group. Fasting and postglucose load insulin concentrations were similar in the normal glucose-tolerant insulin-resistant and IGT groups, but were significantly higher (P < 0.02- < 0.001) than those in normal glucose-tolerant insulin-sensitive individuals. Fasting proinsulin concentrations were also higher (P < 0.002) in the normal glucose-tolerant insulin-resistant (15.1 +/- 1.5 pmol/L) and IGT (15.8 +/- 1.8 pmol/L) groups compared to those in normal glucose-tolerant insulin-sensitive volunteers (9.3 +/- 1.2 pmol/ L). However, the ratio of fasting proinsulin to insulin was identical in all three groups (0.12). When the three groups were combined, significant relationships (P < 0.001) existed between SSPG (degree of insulin resistance) and both fasting proinsulin (r = 0.59) and insulin (r = 0.66) concentrations, but not with the ratio of proinsulin to insulin (r = 0.03). These results demonstrate that fasting proinsulin and insulin concentrations are increased in insulin-resistant, nondiabetic subjects, and the more insulin resistant, the greater the increase. In contrast, the ratio of proinsulin to insulin did not vary as a function of insulin resistance. Thus, neither insulin resistance nor the need to secrete more insulin to maintain glucose tolerance necessarily leads to abnormal insulin processing by the beta-cell.
Glucocorticoid remediable aldosteronism (GRA) is a hereditary cause of mineralocorticoid hypertension. The most common presentation is asymptomatic hypertension. Hypokalemia, hyperaldosteronism and suppressed plasma renin activity are other forms of primary hyperaldosteronism. However, the aldosterone secretion in these patients is regulated by adrenocortico-tropic hormone (ACTH) rather than the reninangiotension system. Here, we report a patient with a 12-year history of hypertension without response to any treatment until dexamethasone was administered. The diagnosis of GRA was confirmed by elevated plasma level of 18-oxocortisol, which is a unique steroid biochemical abnormality of this disease. In GRA, hybrid steroids (18-oxocortisol and 18-hydroxycortisol) are synthesized at the C-18 carbon of cortisol in a similar way as when corticosterone is converted to aldosterone. The gene duplication defect is on chromosome 8 codes for a chimerical 11 beta-hydroxylase/aldosterone synthase enzyme, causing ectopic expression of aldosterone synthase in zona fasiculata. Because this hypertension is remediable by exogenous glucocorticoid, this case was reported to raise attention about treatable aldosteronism.