Preparation of poly(acrylic acid) modified polyurethane membrane for biomaterial by UV radiation without degassing

Poly(acrylic acid) modified polyurethane (AA/PU) membranes were prepared by UV radiation without degassing. The chemical composition of the AA/PU membrane was studied by IR spectroscopy. In addition to those absorption peaks associated with pure PU, the absorption peak at 2400 cm-1 of poly(AA) was also found. The morphology of AA/PU membrane was studied by optical polarizing microscopy. We also measured the glass transition temperature and the decomposition temperature of the AA/PU membrane by differential scanning calorimetry and thermogravimetric analysis. A significant domain was found in the AA/PU membrane, which resulted in different glass transition temperature and decomposition temperature between AA/PU and pure PU membrane. The effect of AA content on the contact angle and water absorption of the AA/PU membrane was determined. It was found that the water content of AA/PU membrane increased with increasing AA content, whereas the contact angle decreased. By using Kaeble's equation and the contact angle data, the surface free energy of AA/PU membrane was determined. The increase of surface free energy resulted from the increase of the dispersion (gammad) term and polar (gammap) term. In order to evaluate the biocompatibility of these membranes, a cytotoxicity test and a cell adhesion and proliferation assay were conducted in cell culture. Immortal cells and primary lymphocytes were both used in this study. The results showed that these AA/PU membranes exhibited very low cytotoxicity and could support cell adhesion and growth. An animal primary test was also done in this study. It was found that the AA/PU membrane could possibly be employed in the treatment of bowel defect.

Prevalence and significance of thyroid autoantibodies in patients with chronic hepatitis C virus infection: a prospective controlled study

OBJECTIVE

To clarify controversies on the prevalence and clinical significance of thyroid autoimmunity in hepatitis C virus (HCV) infection.

DESIGN

A prospective controlled and follow-up study.

PATIENTS AND MEASUREMENTS

Serum thyroid microsomal antibody (TMA) and thyroid stimulating hormone were assayed and compared in a consecutive, unselected series of 130 patients with chronic HCV infection, 130 sex/age (+/- 2 years)-matched patients with chronic hepatitis B virus (HBV) infection and 260 matched normal controls.

RESULTS

The prevalence of thyroid autoantibodies in male patients with chronic HCV was < 2%. The prevalence of TMA (< 1:400) in female patients with chronic HCV infection was significantly higher than that of HBV controls (22.1 vs. 1.6%; P < 0.001), and higher but not significant compared with normal controls (13.5%). However, the trend of increasing prevalence with age in normal controls was not observed in HCV patients. TMA seropositive female HCV patients were not different from seronegative counterparts in age, duration of infection, HLA haplotype, associated autoantibodies and liver histology but had a significantly higher prevalence of genotype 1b/2b mixed infection (P < 0.01) and anti-GOR (P < 0.05). Of the 23 HCV patients seropositive for thyroid autoantibodies, seven had Hashimoto's thyroiditis, two had Graves' disease and three had received subtotal thyroidectomy. During follow-up, four of 15 female patients showed a 14-16-fold increase in TMA titre and one developed hyperthyroidism. Patients with thyroid autoantibodies did not show a propensity to develop thyroid dysfunction during interferon therapy.

CONCLUSIONS

These results suggest a weak association between HCV and thyroid autoimmunity in females. As in the ordinary population with thyroid autoantibodies, they should be evaluated for thyroid status and be followed-up if thyroid autoimmunity is evident. However, seropositivity of thyroid autoantibodies is not a contraindication to interferon therapy.

Surgical treatment of severe perthes disease: comparison of triple osteotomy and shelf augmentation

The optimal management of the severe form of Perthes disease is controversial. This retrospective study evaluated the results of two procedures in two groups of patients with Perthes disease. The Catterall classification was adopted for grouping of patients before treatment. The Herring classification was used for comparison of the follow-up radiographs. Under the concept of surgical containment, triple innominate osteotomy was performed in 14 patients at an average age of 8 years 7 months with a mean follow-up period of 4 years 3 months. Staheli's shelf augmentation was performed in 14 patients at an average age of 10 years 2 months with a follow-up period of 3 years 8 months. Radiologically, femoral head subluxation, acetabular coverage, acetabular angle, and center-edge angle were markedly improved in both groups. In the clinical evaluation using modified Sundt's criteria, both procedures were effective. Satisfactory results were achieved in 79% of 14 patients (5 good, 6 fair, and 3 poor) in the triple osteotomy group, and 100% of 14 patients (two good, 12 fair) in the shelf augmentation group. Nevertheless, triple innominate osteotomy is technically more demanding with a longer operating time and resulted in more complications. Staheli's shelf augmentation is a simpler procedure with better coverage of the acetabulum. However, asphericity of the femoral heads was observed more frequently in this group. The Herring lateral pillar classification was better than the Catterall classification in predicting the final outcomes in this study.

Papillary and follicular thyroid carcinomas with bone metastases: a series of 39 cases during a period of 18 years

BACKGROUND

Bone metastases can cause death in patients with papillary or follicular thyroid carcinoma. There is, however, limited information about the clinical presentations and prognoses of patients with papillary and follicular thyroid carcinomas with bone metastases in Taiwan.

MATERIALS AND METHODS

A series of 39 patients with papillary or follicular thyroid carcinomas with bone metastases treated at our center from 1977 through 1995 was retrospectively reviewed to elucidate the clinical presentations and results of treatment of this disease.

RESULTS

The occurrence rate of bone metastasis in papillary and follicular thyroid carcinomas was 4.3%. Of the 39 patients, whose mean age was 57.5 years, 28 (71.8%) had follicular and 11 (28.2%) had papillary carcinomas. Thirty-two patients (82.1%) were female and 7 (17.9%) were male. Twenty-nine patients (74.4%) presented with bone metastases before the thyroid cancers were diagnosed. Bone metastases were detected using radiography in 33 patients and using 131I scans in 28 patients. Thirty-one patients (79.5%) had multiple bone metastases. The spine was the most frequently involved site (53.8%). Three patients were disease-free and 14 patients died during the course of treatment. Using the Kaplan-Meier method, the 5-year survival rate was estimated to be 64.9%.

CONCLUSION

Bone metastasis, although rare in patients with papillary carcinoma, was not very uncommon in patients with follicular carcinoma. Bone metastases occurred more often in older patients. Multiple bone metastases were noted more often than single bone metastasis. Most patients had symptoms and signs resulting from metastatic bone lesions. Although multimodality therapy was tried, the prognoses for most patients with bone metastases were poor.

Relative value of thallium-201 and iodine-131 scans in the detection of recurrence or distant metastasis of well differentiated thyroid carcinoma

Radioactive iodine (131I) has been found to be more sensitive and more specific than thallium-201 for the detection of distant metastases and thyroid remnants in the neck in cases of well-differentiated thyroid carcinoma. 201Tl has been deemed particularly useful in localizing metastases or recurrence in patients with a negative 131I scan and abnormal levels of serum thyroglobulin (Tg). This study aimed to: (1) determine the value of 201Tl imaging in localizing metastases or recurrence in patients with well-differentiated thyroid carcinoma, and (2) evaluate the false-positive and false-negative results of 131I and 201Tl scintigraphy. Sixty-two thyroid remnant ablated patients who underwent simultaneous postoperative 201Tl and 131I scans and and serum Tg determinations were evaluated. Fifty patients had papillary thyroid carcinomas and 12 had follicular thyroid carcinomas. 201Tl imaging was performed before the 131I studies. Of the 62 patients who underwent 201Tl imaging studies, 24 were found to have positive results, with local recurrence or distant metastases. Patients with positive results in the 201Tl imaging studies tended to be older, were mor often male, had higher Tg levels and had a higher recurrence rate. Of these 24 patients, ten had negative diagnostic or therapeutic 131I scans. Concurrently, serum Tg levels were less than 5 ng/ml in five of these ten patients. Three patients were deemed false positive by 201Tl scans; one had a parotid tumour, one a periodontal abscess and one lung metastasis. Among the 38 patients with negative 201Tl scans, 11 had positive findings on 131I scans. Three had distant metastases: two with lung metastases and one with bone metastases. Patients with false-positive results on 131I scans included those with biliary tract stones, ovarian cysts, and breast secretion. Of the 27 patients with negative 201Tl and 131I scans, 15 had elevated serum Tg levels. Among these, local recurrence followed by lung metastases was manifested in a 49-year-old male with papillary thyroid carcinoma. In conclusion, both 131I and 201Tl scans are useful in the detection of recurrence or distant metastasis of well differentiated thyroid cancers. 201Tl scan could in particular be used in patients with a negative 131I scan in conjunction with an elevated Tg level.

Endocrinological aspects of Langerhans cell histiocytosis complicated with diabetes insipidus

Langerhans cell histiocytosis (LCH) is a rare disorder and may be complicated with hypopituitarism and diabetes insipidus (DI) due to invasion of the hypothalamic-pituitary area. In this study, 10 patients with complete (4) and partial (6) type central DI were found among 125 LCH patients in our hospital records. The water deprivation test, followed by the pitressin test, was performed to confirm DI. Hypothalamic-pituitary endocrine function tests were carried out on these 10 patients at the initial diagnosis and during follow-up. All patients revealed growth hormone insufficiency in the insulin hypoglycemic tolerance test. Four patients had impairment of cortisol secretion, demonstrated by insulin hypoglycemic stimulating test results. Two patients had poor response in the thyrotropin releasing hormone stimulating test. Two patients had only partial responses in the luteinizing hormone releasing hormone test. Four patients had hyperprolactinemia. All patients underwent surgical treatment followed by chemotherapy and/or radiotherapy. One patient completely recovered from the endocrine disorder, 3 patients required smaller doses of desmopressin, and one patient had normal adrenal, thyroid, and gonadal function. Hypothalamic-pituitary disorders in LCH should not be neglected. Treatment of LCH can partially or completely reverse associated endocrine disorders. Therefore, endocrine studies and hormone replacement should be mandatory for patients with LCH.

Content of reduced glutathione and consequences in recipients of glucose-6-phosphate dehydrogenase deficient red blood cells

The red blood cell glucose-6-phosphate dehydrogenase (G6PD) activity of every donor was examined with automatic enzyme-coupled method. The technique of molecular biology was applied to determine the DNA mutations for the 97 donors with undetectable G6PD activity. The concentration of reduced glutathione (GSH) in the stored RBC of the 97 G6PD-deficient donors and 124 normal donors was determined with the technique of high performance liquid chromatography. Routine blood counts, bilirubin and haptoglobin levels were used to evaluate posttransfusional hemolysis for the 48 adult patients transfused with 1 U G6PD deficient and 1 U normal RBC. Most (88, 90.7%) of the 97 donors were confirmed to be G6PD deficient at the DNA level. At each age interval of storage, the GSH concentration of G6PD-deficient RBC was significantly different from that of normal RBC. The total average value of GSH (pmol/gHb) was 2.52 +/- 0.95 (mean +/- 1 standard deviation) vs. 3.74 +/- 1.43 (P < 0.001). Hemoglobin, hematocrit, bilirubin, and haptoglobin levels in the patients receiving G6PD-deficient RBC were not statistically different from those in the recipients of normal RBC; even though the age of stored blood was 26-35 days. Within the same group of patients, the results of bilirubin and haptoglobin were not significantly changed before and after transfusion. The results of this study show that the GSH concentration in the stored blood of G6PD deficient donors was 67% of that in the normal donors. However, hemolysis does not occur in adult patients transfused with 1 U G6PD-deficient RBC. It seems unnecessary to screen G6PD activity for donors of adult recipients in Taiwan.

Use of radioactive iodine for thyroid remnant ablation in well-differentiated thyroid carcinoma to replace thyroid reoperation

Complete thyroidectomy was recommended for patients with well-differentiated thyroid carcinoma to remove any potential residual contralateral cancer tissue and to facilitate detection of metastatic lesions by radioactive iodide (131I). Unfortunately, 8-32% incidence of severe complications were noted after reoperation. At present, there are still not enough data about the ablative effect of 131I for such conservative surgical treatment of well-differentiated thyroid cancers. The major goal of the present study was to examine the effects of 311I for ablation of thyroid remnants in order to obviate the severe complications associated with reoperation. From January 1977 to December 1995, 210 papillary or follicular thyroid carcinoma patients received subtotal thyroidectomy or lobectomy. After the operation, 46 of the 210 patients received 131I for remnant ablation. At doses of > or = 30 mCi 131I, 38 thyroid remnants were successfully ablated; 25 of 38 (65.8%) patients successfully ablated patients received 30 mCi 131I one-four times. Five patients expired during the follow-up period, including two follicular carcinoma patients who were misinterpreted as having benign lesions in the first operation. Patients in the overall failure versus success group for thyroid remnant ablation revealed increased age, histopathology of follicular carcinoma, higher postoperative 131I uptake in the neck bed, higher postoperative thyroglobulin levels, bigger tumor size, and higher mortality. In conclusion, repeated 30 mCi 131I treatments were adequate for most thyroid remnant ablations following subtotal thyroidectomy or lobectomy in well-differentiated thyroid cancer patients. Misinterpretation of follicular cancer as benign lesions and unresectable tumor comprised the main reasons for mortality.

Acute suppurative thyroiditis and aggressive malignant thyroid tumors: differences in clinical presentation

BACKGROUND AND OBJECTIVES

Aggressive malignant thyroid tumors (AMTT) may mimic the clinical symptoms and signs of acute suppurative thyroiditis (AST) in the early course of the disease process. Our objective was to analyze the clinical features of these two conditions, to assess the best way of early diagnosis, and to propose proper treatment.

METHODS

We retrospectively reviewed and analyzed the clinical features of 30 patients, who had similar clinical pictures of AST and were managed at Chang Gung Memorial Medical Center in Linkou, Taiwan, during the period from 1983 to 1996. These patients were consequently diagnosed as either AST or AMTT. The data were analyzed by the Mann-Whitney U, chi-square and Fisher's exact tests.

RESULTS

Among the 30 patients, 25 patients (Male/Female (M/F) ratio = 9/16) were diagnosed as having AST and 5 (M/F ratio = 1/4) as AMTT. After statistical analysis we concluded that the presence of the following factors, namely, older age at diagnosis (P = 0.0155), history of dysphonia (P = 0.0325), right thyroid lobe involvement (P = 0.0151), large size of lesions (P = 0.0013), presence of anemia (P = 0.0075), and sterile pus cultures from thyroid aspirates (P = 0.0013) were cause to suspect a malignancy if the condition did not improve after antibiotics. Delay in diagnosis and management of AMTT may result in a poor prognosis (P = 0.0082).

CONCLUSION

Due to the high mortality rate of AMTT, we should closely observe the patients with poor prognostic variables of acute thyroiditis. Earlier detection and aggressive surgical intervention for AMTT might improve the outcome.

Computer-assisted design of new drugs based on retrometabolic concepts

Retrometabolic drug design approaches incorporate metabolic and toxicological considerations into the drug design process and represent a novel, systematic methodology for the design of safe compounds. Two major design concepts aimed to increase the therapeutic index (the activity/toxicity ratio) of drugs were developed. Chemical delivery systems (CDS) are primarily used to allow targeting of the active biological molecules to specific target sites or organs based on predictable enzymatic activation. Soft drug approaches are used to design new drugs by building in the molecule, in addition to the activity, the most desired way in which the molecule is to be deactivated and detoxified subsequent to exerting its biological effects. Special computer programs were developed that starting from a lead compound generate complete libraries of possible soft analogs and then help ranking these candidates based on isosteric-isoelectronic comparisons, predicted solubility/partition properties, and estimated metabolic rates. The novel field of large peptide-CDSs imposes special challenges, but a new, remarkably simple model was developed to estimate partition properties for a wide range of compounds, including quite large peptide derivatives. A suggested change of about five order of magnitudes in the distribution coefficient can explain the "lock in" mechanism of brain-targeting delivery systems.

Two novel glucose 6-phosphate dehydrogenase deficiency mutations and association of such mutations with F8C/G6PD haplotype in Chinese

Glucose 6-phosphate dehydrogenase (G6PD) deficiency is a common genetic disease affecting 3% of the total Chinese population in Taiwan. To investigate the molecular basis of this deficiency, we analyzed blood samples from G6PD-deficient newborns using a nonradioactive polymerase chain reaction coupled with single-stranded conformation polymorphism (PCR-SSCP) analysis. We identified two novel G6PD mutations in Chinese. The first, G6PD Miaoli, involved a C-->G substitution at nucleotide (nt) 519, producing a Phe173 to Leu change in the protein. The second mutation (G6PD Keelung) involved a C-->T change at nt 1387, resulting in an Arg463 to Cys substitution. The F8C/G6PD (coagulation factor VIIIc) haplotype that spans the Xq28 region from the gene for coagulation factor VIIIc to the gene for G6PD was also investigated in Chinese using PCR and restriction enzyme digestion. Of the 16 possible haplotypes, only four were found, which suggests that these four polymorphic sites are in strong linkage disequilibrium. Analysis of the association of G6PD mutations with F8C/G6PD haplotype revealed that nt 517, 592, 835, and 1387 mutations are linked to haplotype VI+VII, whereas the nt 519 mutation is linked to haplotype III. The finding that some G6PD mutations are associated with a particular F8C/G6PD haplotype may be useful for future population studies.

Clinical presentations and predictive variables of thyroid microcarcinoma with distant metastasis

BACKGROUND

Thyroid microcarcinoma is not an uncommon disorder. The purpose of this study is to analyze the clinical presentation and predictive factors for patients with thyroid microcarcinomas who have distant metastases.

METHODS

We retrospectively reviewed and analyzed the clinical variables of 97 patients with thyroid microcarcinoma during the period from 1977 to 1995. The patients were divided into 2 groups representing patients with and without distant metastases. These data were analyzed by the Mann-Whitney U, chi 2 and Fisher's exact tests.

RESULTS

Of the 97 patients with thyroid microcarcinomas, there were 6 (6.2%) cases (F/M = 5/1) with distant metastases. Among them, 4 cases were papillary carcinomas and 2 cases were follicular carcinomas. The parameters: age at diagnosis (P = 0.0137), one month postoperative serum thyroglobulin (Tg) level (P = 0.0215), cervical lymph node metastasis (P = 0.0097), and follicular cell type (P = 0.0079), were determined to be factors predictive for distant metastases by statistical analysis. There were no statistical differences between gender (P = 0.5781), postoperative 131I uptake (P = 0.1238), tumor size (P = 0.0571), preoperative thyroid function (P = 0.4425), fine-needle aspiration cytology (FNAC) (P = 0.9723), preoperative thyroid scan (P = 0.9765), and operative methods (P = 0.1060) between these two groups.

CONCLUSIONS

Most thyroid microcarcinomas presented with relatively benign clinical courses, but patients with adverse predictive factors need more aggressive interventions to improve outcome.

Results of external beam radiotherapy in patients with well differentiated thyroid carcinoma

Surgical, thyroid hormone and radioactive 131I therapy are the standard curative treatments for well differentiated thyroid cancer. However, for residual, recurrent and nodal involvement of well differentiated thyroid cancer, external radiotherapy may be important in preventing distant metastases. The postoperative treatment of well differentiated human thyroid cancer with external radiotherapy is controversial. We retrospectively reviewed the records of 699 patients with papillary or follicular thyroid cancer, of whom 72 received external radiotherapy treatment after surgery. Thirty-two of these patients were at clinical stage 2 or 3 at the time of diagnosis while 172 patients at clinical stages 2 or 3 did not receive external radiotherapy after surgery. The patients who received external radiotherapy were older than those who did not (42.9 +/- 14.5 vs. 38.6 +/- 15.3), although this was not statistically significant. There were no significant differences in clinical parameters including surgical methods employed, histopathological types of cancer, follow-up stages, postoperative thyroglobulin levels, tumor size, accumulated 131I doses and survival rates between the two groups. To clarify the effect of external radiotherapy in patients with local invasion, we compared the survival rates of the patients with clinical stage 3 in the two groups and again no significant difference was found. During the follow-up period, 21 (28.4%) of the 72 patients who received external radiotherapy died of thyroid carcinoma. In our limited period of study, external radiotherapy did not improve the survival rate of patients with well differentiated thyroid cancer, though it appeared to cause temporary tumor regression.

The clinical significance of gall-bladder non-visualization in cholescintigraphy of patients with choledochal cysts

Intravenous radionuclide cholescintigraphy (IVRC) provides a very specific picture for choledochal cysts. However, the clinical significance of the non-visualization of the gall-bladder (GB) activity in these cases is unclear. In this study, we reviewed 27 patients with choledochal cysts who underwent IVRC within 7 days prior to operation and correlated the GB findings on IVRC with the histopathological results. In 18 of the 27 patients (66.7%), there was non-visualization of the GB at 4 h post injection. Among these, two had histopathological features of acute cholecystitis (AC), 11 had chronic cholecystitis (CC), and five had normal GBs. In the other nine patients with visualization of the GB, there were five cases of CC and four normal GBs. If we apply the finding of non-visualization of the GB at 4 h post injection as the criterion for the diagnosis of AC, the diagnostic accuracy was only 40.7% (11/27). We concluded that: (1) GB disease (AC and CC) was common (66.7%: 7.4% and 59.3% respectively) in choledochal cyst patients. (2) Non-visualization of the GB on IVRC did not necessarily indicate AC in choledochal cyst cases, and the diagnostic accuracy was low. (3) GB disease is not the only cause of GB non-visualization on IVRC. A huge choledochal cyst causing a mass or reservoir effect may be a cause of GB compression and result in non-visualization of the GB.

G6PD NanKang (517 T-->C; 173 Phe-->Leu): a new Chinese G6PD variant associated with neonatal jaundice

Using a non-radioactive PCR-SSCP technique, we identified a novel glucose-6-phosphate dehydrogenase (G6PD) mutation in a Chinese newborn with neonatal jaundice. This new variant (G6PD NanKang) causes a T to C change at nucleotide position 517, producing a Phe173Leu substitution in the human G6PD protein. Since the 517 mutation does not create or remove any known restriction site, we introduced an artificially created site by adding a primer containing a mismatched base to the PCR reaction mixture. The mismatched base accompanying the nearby 517 T-->C mutation generates an XhoI site which is suitable for distinguishing normal from mutant alleles. Using this approach, the 517 mutation can be diagnosed quickly at the DNA level.

Parathyroid carcinoma with postoperative prolonged hypocalcemia in a patient with chronic renal failure

Parathyroid carcinoma is a rare disease that usually presents with severe hypercalcemia and marked elevation of parathyroid hormone level. A 64-year-old male patient with repeated episodes of renal stones sustained chronic renal failure. Subsequently, he developed acute uremic symptoms and underwent a left upper parathyroidectomy. Parathyroid carcinoma was diagnosed after surgery. Asymptomatic hypocalcemia was the initial presentation. Protracted symptomatic hypocalcemia developed 8 months postoperatively, accompanied by an extremely high parathyroid hormone level. Delayed "bone hunger" syndrome concomitant with down-regulation of the parathyroid hormone receptors or production of parathyroid hormone with diminished bioactivity may have been the possible causes.

Identification of malnutrition-related diabetes mellitus among hospitalized patients in Taiwan

A retrospective review of 1,089 diabetes mellitus admitted to the metabolic ward of Chang Gung Memorial Hospital was performed to screen for malnutrition-related diabetes mellitus (MRDM). None of the patients fulfilled the MRDM criteria, although 20 patients with a body mass index < or = 15 kg/m2 were further analyzed. These patients presented with poor glycemic control and most had associated chronic diseases. C-peptide levels were < 0.8 ng/mL in 17 patients and undetectable in six patients. Two patients experienced diabetic ketoacidosis (DKA). Insulin treatment was required by 18 patients with a mean (+/- SD) dosage of 30 +/- 9 U/day. During follow-up of 14 of the patients for 9.8 +/- 4.3 months, HbA1c decreased significantly. Their mean body weight and body mass index increased significantly from 36.6 +/- 4.6 kg to 47.2 +/- 6.2 kg and 13.9 +/- 0.9 to 18.0 +/- 1.9 kg/m2, respectively. Careful attention should be paid to diabetic control and associated chronic illness in patients with severe undernutrition.

Neonatal jaundice and molecular mutations in glucose-6-phosphate dehydrogenase deficient newborn infants

Molecular mutations of the glucose-6-phosphate dehydrogenase (G6PD) gene and clinical manifestations of neonatal jaundice in 112 male and 50 female Chinese neonates with G6PD deficiency were studied. In the 112 males, the nucleotide (nt) 1376 (G-->T) mutation was the dominant type (50.0%), followed by nt 1388 (G-->A) (16.1%), nt 493 (A-->G) (8.0%), nt 1024 (C-->T) (6.2%), nt 95 (A-->G) (5.4%), nt 392 (G-->T) (1.8%), nt 487 (G-->A) (1.8%), nt 871 (G-->A) (0.9%), and nt 1360 (C-->T) (0.9%). The nt 871 variant has not been reported in Taiwan before. The occurrence rates for nt 1376, nt 1388, nt 493, nt 95, and nt 1024 mutations in the 50 females were 44.0%, 18.0%, 12.0%, 6.0%, and 6.0%, respectively. The type of G6PD mutation in 10 male and 7 female neonates has not been identified yet. Although G6PD deficient neonates had higher frequency of phototherapy than G6PD normal neonates in both sexes, a significant difference in the prevalence of hyperbilirubinemia (peak bilirubin > or = 15.0 mg/dl) between G6PD deficient and normal neonates was found only in males. Further analysis showed that duration of phototherapy was longer in G6PD deficient male neonates than in the control group, while the outcome of phototherapy was better in subjects with non-nt 1376 mutations than subjects with the nt 1376 mutation. Most (78.3%) of the 23 G6PD deficient neonates who subsequently suffered from neonatal hyperbilirubinemia carried the nt 1376 mutation. The results of this study indicate that the nucleotide substitution at 1376 is the most common and important mutation for G6PD deficiency in Chinese neonates in Taiwan.

Comparison of the outcome between the calculated dosimetry and the estimated dosimetry of 131I in the treatment of hyperthyroidism

To compare the outcomes of different methods in prescribing the optimal dose of radioactive iodine (131I) for the treatment of hyperthyroidism, we retrospectively analyzed 52 patients with toxic diffuse goiter. They received single dose of 131I for the treatment of hyperthyroidism. In addition, all of them met the following criteria: 1) symptoms and signs of hyperthyroidism; 2) elevated blood triiodothyronine (T3) and thyroxin (T4) by radioimmunoassay (RIA) method; 3) diffuse goiter with increase of uptake proved by thyroid scintiscan; 4) only one dose of 131I was given during the follow-up period; 5) well-documented thyroid function test in the medical chart during the follow-up period (6 months, 1 year, 2 years and 5 years after 131I therapy). The enrolled patients were divided into estimated and calculated group. The dose of 131I in the calculated group was obtained from the measurement of size and 131I uptake of thyroid gland. The dose of 131I in the estimated group was prescribed according to the size of thyroid gland by physical examination, and the association with cardiac arrhythmia, congestive heart failure, or ischemic heart disease. The mean doses of 131I were 4.8 +/- 1.4 mCi and 7.0 +/- 1.1 mCi in the calculated and estimated group respectively. In this study, there were no significant difference in the incidence of euthyroidism, hyperthyroidism, and hypothyroidism between these two groups in thefollow-up period after 131I therapy. In view of simplicity and time-saving, it is a practical choice to prescribe the dose of 131I therapy for toxic diffuse goiter according to the size of thyroid gland and the associated cardiac condition.

Preparation, characterization, and anesthetic properties of 2-hydroxypropyl-beta-cyclodextrin complexes of pregnanolone and pregnenolone in rat and mouse

Prototype formulations of the progesterone derivatives pregnanolone and pregnenolone were prepared by solubilizing the steroids in 2-hydroxypropyl-beta-cyclodextrin (HP beta CD). The aqueous solubility of the steroids was increased as a function of HP beta CD concentration generating linear (AL) or curvilinear (AP) phase-solubility profiles. While the solubility of pregnanolone could not be increased with the addition of water-soluble pharmaceutical polymers, the concentration of pregnenolone in HP beta CD was increased more than 60% by the addition of small amounts (0.10%) of (hydroxypropyl)methylcellulose. Mice studies found that while pregnanolone was highly potent in an HP beta CD vehicle, pregnenolone was devoid of activity. Since pregnenolone and pregnanolone differ marginally in structure and physicochemical profile, the data suggest that these derivatives interact via a specific receptor and not via nonspecific membrane perturbations. Sex differences in the action of the pregnanolone complex was observed in that parenteral (i.v. and i.p.) drug administration was more effective in males than females. These data are in contrast to observations made in the case of alfaxalone, a related steroid anesthetic, in which the sex difference favored female animals. On the other hand, females appeared to be more sensitive to the effects of the pregnanolone complex when administered orally. Finally, parenteral pregnanolone was more toxic to males than females with LD50 (i.v.) values of 355 and 548 micromol/kg, respectively.

Expression of vascular cell adhesion molecule-1 by follicular dendritic cells

Follicular dendritic cells are the major supporting cell of the germinal center microenvironment. The major function of follicular dendritic cells is to present antigen to B cells in secondary lymphoid tissues. Through cell-cell interactions, FDCs are hypothesized to be central to the regulation of normal B cell growth and differentiation. The major receptor-ligand pair which mediates B cell-FDC adhesion is the beta 1 integrin VLA-4, present on B cells and VCAM-1 expressed on FDCs. Follicular non-Hodgkin's lymphomas similarly employ this mechanism to bind to neoplastic germinal centers. The VCAM-1 molecule can exist as a 6 or 7 immunoglobulin domain form. The major form of VCAM-1 on activated endothelium is the 7 domain form. In this report we have determined by polymerase chain reaction of purified FDCs that they express predominantly mRNA for 7 domain VCAM-1. It is likely that the two forms of VCAM-1 are associated with distinct functions, therefore the expression of 7 domain VCAM-1 may be important in normal and neoplastic B cell-FDC interactions.

Clinical associations between thyroid and liver diseases

The liver has an important role in thyroid hormone metabolism and the level of thyroid hormones is also important to normal hepatic function and bilirubin metabolism. Besides the associations between thyroid and liver diseases of an autoimmune nature, such as that between primary biliary cirrhosis and hypothyroidism, thyroid diseases are frequently associated with liver injuries or biochemical test abnormalities. For example, thyroid diseases may be associated with elevation of alanine aminotransferase and alkaline phosphatase, which is mainly of bone origin, in hyperthyroidism and aspartate aminotransferase in hypothyroidism. Liver diseases are also frequently associated with thyroid test abnormalities or dysfunctions, particularly elevation of thyroxine-binding globulin and thyroxine. Hepatitis C virus infection has been connected with thyroid abnormalities. In addition, antithyroid drug therapy may result in hepatitis, cholestasis or transient subclinical hepatotoxicity, whereas interferon (IFN) therapy in liver diseases may also induce thyroid dysfunctions. These thyroid-liver associations may cause diagnostic confusions. Neglect of these facts may result in over of under diagnosis of associated liver or thyroid diseases and thereby cause errors in patient care. It is suggested to measure free thyroxine (FT4) and thyroid-stimulating hormone (TSH) which are usually normal in euthyroid patients with liver disease, to rule out or rule in coexistent thyroid dysfunctions, and consider the possibility of thyroid dysfunctions in any patients with unexplained liver biochemical test abnormalities. It is also advisable to monitor patients with autoimmune liver disease or those receiving IFN therapy for the development of thyroid dysfunctions, and patients receiving antithyroid therapy for the development of hepatic injuries.

Theoretical studies on the structures of natural and alkylated cyclodextrins

A series of semiempirical molecular orbital calculations using the AM1 method have been performed on isolated natural and alkylated alpha- and beta-cyclodextrins. For natural cyclodextrins, three geometries were considered: (i) molecular mechanics (MM2); (ii) AM1 fully optimized geometry; (iii) X-ray structures based on the experimental coordinates for heavy atoms with positions of hydrogen atoms optimized by AM1. Large differences between AM1 calculated properties of geometries i-iii were found. The differences between ii and iii are smaller and reflect the intermolecular, crystal packing forces. Comparisons are made between ii and iii and properties determined therefrom, such as cavity diameter, outer diameter, and height. In addition, AM1 semiempirical calculations were performed on the mixed (2,3,6) (hydroxyprophyl)-beta-cyclodextrin, 2,6-dimethyl-beta-cyclodextrin, and 2,6-bis(hydroxypropyl)-beta-cyclodextrin. The results were compared with the substituent effects on monoglucose. It was found that the alkylation and methyl and 2-(hydroxypropyl) functions on beta-cyclodextrin does not introduce significant steric hindrance.

Efficacy of a 3-substituted versus 17-substituted chemical delivery system for estradiol brain targeting

Brain-targeted delivery of estrogens has been achieved by a chemical delivery system (CDS) in which a molecular targetor (1-methyl-1,4-dihydronicotinate) was attached to the 17-alcohol of estradiol. Optimization of this effect was attempted with the isomeric 3-phenol ester. Estradiol 3-nicotinate was prepared with nicotinic anhydride, which selectively acylated the phenol position. Methylation and reduction gave estradiol 3-(1-methyl-1,4-dihydronicotinate) of the 3-E2-CDS. Theoretical and electrochemical investigation indicated that the 3-E2-CDS was more stable to oxidation than was the prototype 17-ester (17-E2-CDS). Systemic administration of the 17-E2-CDS produced high levels of the corresponding quaternary salt in the brain of rats, which disappeared with an estimated half-life of > 2 days, but 3-E2-CDS dosing resulted in no significant quaternary salt trapping. Pharmacological activity was potent and sustained after 17-E2-CDS dosing but transient after 3-E2-CDS administration. Thus, the 3-E2-CDS reduced the rate of weight gain in male rats but to a lesser extent and for a shorter duration than did the 17-E2-CDS. Similar effects were seen on pituitary hypertrophy, reduction in serum androgen concentrations, and involution of prostate and seminal vesicles. The results of these studies suggest that placement of the targeting ester at the phenol position increases dihydropyridine stability but, at the same time, reduces brain sequestration.

Thyroid cancer treated in Chang Gung Memorial Hospital (northern Taiwan) during the period 1979-1992: clinical presentation, pathological finding, analysis of prognostic variables, and results of treatment

This study is a retrospective analysis of 248 thyroid cancer patients who received their primary treatment in the Chang Gung Memorial Hospital during the period January 1979 to December 1992. Among these cases, there were 173 papillary thyroid cancers (69.8%), 52 cases of follicular thyroid cancer (21%), 7 cases of medullary thyroid cancer (2.8%), and 16 cases of anaplastic thyroid cancer (6.5%). The subjects included 184 female patients with a mean age of 40.7 +/- 14.3 years and 64 males patients with a mean age of 49.2 +/- 14.3 years. Most of the cases had a nearly total thyroidectomy after the diagnosis was confirmed by frozen section during the operation. During the follow-up period, 19 (8.2%) patients diagnosed with well-differentiated thyroid cancer died of thyroid cancer in contrast to 12 patients (75%) with anaplastic thyroid cancer. The 1-year Greenwood survival probabilities after the disease is diagnosed in papillary, follicular, and anaplastic thyroid cancer are 0.98, 0.86, and 0.25, respectively. For the analysis of prognostic variables in well-differentiated thyroid cancer patients, 16 factors were entered for univariate and multivariate analysis. Using a log-rank univariate analysis, survival was significantly associated with the cell type of the primary tumor, age, clinical staging, postoperative 131I pattern, tumor size, postoperative thyroglobulin (Tg) level and postoperative x-ray results. In the Cox multivariate regression analysis the combination factors that gave the best prognostic value were the association of x-ray finding (P = .004), age (P = .017), and Tg level (P = 0.19). In conclusion, thyroid cancer is not an unusual disease in Taiwan. As previously reported anaplastic thyroid cancer has a poor prognosis. In this limited period of follow-up study, the patients' age with postoperative first positive x-ray finding and Tg level may provide the prognostic factors for patients with well-differentiated thyroid cancer.

Sequential liver and bone biochemical changes in hyperthyroidism: prospective controlled follow-up study

OBJECTIVE

To reexamine the prevalence and sequential changes of liver and bone biochemical abnormalities in patients with hyperthyroidism.

METHODS

A consecutive series of 95 patients with hyperthyroidism and 66 controls with euthyroid goiter seen during same period were studied. The patients were treated with propylthiouracil (PTU) 300 mg/day for 2 months, followed by 100-150 mg/day for 3 months and a subsequent maintenance dose of 100 mg/day. Serum aspartate amino-transferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (GGT), bilirubin, ALP isoenzymes, and hepatitis markers were studied before therapy and at 2 and 5 months after PTU therapy was begun.

RESULTS

Seventy-two [75.8%, confidence interval (CI) 67.2-84.4%] of the 95 patients had at least one biochemical abnormality. AST, ALT, ALP, GGT, and bilirubin were elevated in 27.4%, 36.8%, 64.2%, 16.8%, and 5.3%, respectively. Of the 34 patients with ALT elevation, 62% showed gradual normalization of ALT, whereas 38% (CI 21.9-54.5%) showed transient, asymptomatic, but significant (p < 0.025) further elevation of ALT during PTU therapy. Overt hepatitis developed in one patient. None of these changes was due to hepatitis A, B, C, or delta virus infection or autoimmune hepatitis. Changes of serum GGT parallel those of ALT. In contrast, serum ALP (primarily bone isoenzyme) rose significantly (p < 0.01) as T4 and T3 levels declined at 2 months after therapy.

CONCLUSIONS

The results suggest that hyperthyroidism is often associated with abnormal biochemical tests, particularly ALP elevation, and thus may pose diagnostic confusion. The increase of bone isoenzyme accounts for the elevations in total ALP level before and during therapy. Serum ALT and GGT abnormalities usually subside during PTU therapy, but transient asymptomatic PTU hepatotoxicity occurs in one-third of the patients. Discontinuation of PTU is not required unless overt hepatitis develops.

Expression and biochemical characterization of human glucose-6-phosphate dehydrogenase in Escherichia coli: a system to analyze normal and mutant enzymes

We have developed a system to characterize normal and mutated glucose-6-phosphate dehydrogenase (G6PD) enzymes in vitro. Normal or mutant G6PD cDNA was subcloned into a pGEX-3X vector, which allowed production of a functional fusion protein in Escherichia coli. When we compared the recombinant normal enzyme with authentic human G6PD, indistinguishable Km values for glucose-6-phosphate (G6P) and NADP were obtained, and the utilization rates for two substrate analogues (2-deoxy G6P and deamino NADP) also showed no difference between the enzymes. This system was used to assay a biochemically uncharacterized variant, G6PD Taipei (493 A-->G; 165 Asn-->Asp), plus two other known mutations (487 G-->A; 163 Gly-->Ser and 592 C-->T; 198 Arg-->Cys) that are located close to or within the putative G6P binding domain. Our results show that the G6PD activities of these three mutants were greatly reduced. No significant alteration in G6PD kinetics was observed for both 487 and 493 mutations. However, a drastic reduction in the Km for G6P (4-fold decrease) and tremendous increases in utilization rates of 2-deoxy G6P (32-fold increase) and deamino NADP (6-fold increase) were associated with the 592 mutation. This results suggests that arginine 198 in human G6PD, possibly located within the putative G6P binding domain, may play an important role in binding the substrate G6P. In addition, we and others have recently identified that at least nine different types of mutations are responsible for G6PD deficiency in Chinese. In this report, we also present the occurrence rate of each mutation present in the population of Taiwan.

Insulinoma--clinical experience in ten cases

During the period between January 1981 and December 1992, a total of ten patients with pathologically confirmed insulinoma were studied. All patients presented with variable degrees of neuroglycopenic symptoms and Whipple's triad. The ratio of insulin to glucose after an overnight fast was greater than 0.3 in 90% (9/10) of patients. Eight patients who received supervised fasting developed neuroglycopenia with relative hyperinsulinemia within 48 hours of fasting. Four of 8 patients developed hypoglycemia during a 5-hour oral glucose tolerance test (OGTT). Calcium infusion test was more sensitive in patients with an initially higher plasma glucose. The detection rates of various localization studies were 12.5% (1/8) by abdominal ultrasonography, 37.5% (3/8) by abdominal CT scan, 50% (5/10) by selective superior mesenteric and celiac arteriography. Transhepatic portal venous sampling (THPVS) detected insulinomas in 4 of 4 cases. Endoscopic ultrasonography and intraoperative ultrasonography were performed on 1 and 2 cases respectively, and were able to localize the lesions successfully. All patients received surgical treatment including enucleation (n = 2), subtotal pancreatectomy (n = 3) and distal pancreatectomy (n = 5). All patients had single tumors which were all benign islet cell adenomas. The mean size of the tumors was 15.5 +/- 2.0 mm in diameter (range: 8 to 30 mm) and mainly located in the body (50%) and tail (40%), only 1 in the pancreatic head. All symptoms of hypoglycemia subsided after operation. Hyperglycemia was observed in all patients immediately after operation, and most of them resumed normoglycemia within 8 days. However, the 2 patients who had impaired OGTT preoperatively had persistent hyperglycemia after operation and therefore were diagnosed as having diabetes (NIDDM).

Value of serum alkaline phosphatase in evaluating hyperplasia of parathyroid glands in chronic hemodialysis patients

To investigate the value of serum alkaline phosphatase in evaluating hyperplasia of parathyroid glands in hemodialysis patients, 28 hemodialysis patients who had parathyroid sonography examinations for secondary hyperparathyroidism were studied retrospectively. There were significant elevations of serum alkaline phosphatase, parathyroid hormone (PTH), serum total calcium, and dialysis duration in patients with sonography-detectable parathyroid (N = 17) as compared with those of sonography-undetectable (N = 11) parathyroid. Hemodialysis patients who have both higher serum alkaline phosphatase (> 94 IU/L) and considerably elevated serum PTH (9 x or higher) are likely to have sonography-detectable parathyroids (positive predictive value of 93%). Patients with mildly or moderately elevated serum PTH but normal serum alkaline phosphatase are less likely to have sonography-detectable parathyroids (negative predictive value is 100%). These findings suggest that the elevation of serum alkaline phosphatase could be a valuable parameter in addition to the high serum PTH level in predicting hyperplasia of parathyroid glands in chronic hemodialysis patients.

Effect of gliclazide on plasma lipids and pancreatic beta cell function in non-insulin-dependent diabetes mellitus

Eighteen patients with non-insulin-dependent diabetes mellitus (NIDDM), who were newly diagnosed or had their oral hypoglycemic agents discontinued for more than 3 months, were studied to evaluate the effect of gliclazide on glycemic control, plasma lipids and beta cell function. The mean fasting plasma glucose (249 +/- 11 vs 170 +/- 10 mg/dl, p < 0.001), postprandial plasma glucose (353 +/- 16 vs 237 +/- 16 mg/dl, p < 0.001) and HbA1C (9.6 +/- 0.4 vs 6.5 +/- 0.3% p < 0.001) decreased significantly after 3-months of gliclazide treatment. The beta cell function showed a significant increase in fasting serum C-peptide (1.8 +/- 0.2 vs 2.1 +/- 0.3 ng/ml, p < 0.05) and an insignificant increment in serum C-peptide after glucagon stimulation (2.2 +/- 0.3 vs 2.2 +/- 0.4 ng/ml, p < 0.1). In 8 cases with an initial serum cholesterol above 200 mg/dl, the serum cholesterol decreased significantly (236 +/- 8 vs 200 +/- 12 mg/dl, p < 0.05). However, LDL-cholesterol (164 +/- 8 vs 145 +/- 13 mg, p > 0.05) and HDL-cholesterol (66 +/- 5 vs 54 +/- 9 mg, p > 0.05) showed insignificant decrease after gliclazide therapy. In 4 patients with hypertriglyceridemia, the serum triglyceride decreased (441 +/- 161 vs 239 +/- 73 mg/dl, p > 0.1), but this was not statistically significant. These findings suggest that hyperglycemia, fasting serum C-peptide levels and hypercholesteremia are significantly improved after a 3-month period of gliclazide therapy in NIDDM patients.

Technetium-99m pertechnetate scan for ectopic gastric mucosa in children with gastrointestinal bleeding

The detectability of ectopic gastric mucosa by Technetium (Tc)-99m pertechnetate abdominal scanning was investigated by reviewing 62 such scans in 52 pediatric patients with gastrointestinal hemorrhage. The histologic diagnoses and clinical conditions were correlated to the findings of the scans. There were 21 true-positives, 35 true-negatives, one false-positive and five false-negative studies. The overall sensitivity of this scan for the detection of ectopic gastric mucosa was 81%, the specificity was 97% and the accuracy was 90%.

Abnormalities of sodium transport in non-insulin-dependent diabetes: association with renal disease

We investigated both sodium-lithium countertransport (Na-Li CT) and ouabain-sensitive sodium transport (Na pump) of erythrocytes in healthy subjects (group A), patients with non-insulin-dependent diabetes (NIDDM) without nephropathy (group B), patients in the proteinuric stage (group C), and those in the renal insufficiency stage (group D). Erythrocytes from all four groups had a similar initial water and ionic content and were loaded with similar degrees of Li and Na for efflux studies. There were no significant differences in erythrocyte Na-Li CT or Na pump among the four groups. However, the maximal rate of Na-Li CT was significantly higher in a group of subjects with essential hypertension when compared with groups A, B and C, consistent with the view that there is a genetic marker for essential hypertension. Ouabain-insensitive Na efflux (Na leak) of erythrocytes was found to be significantly higher in group D than in groups A or B. Also, a significant positive correlation existed between Na leak and urine protein levels of the subjects studied. Our results thus indicate that in contrast with insulin-dependent diabetic patients (IDDM) where an elevated Na-Li CT is observed, with diabetic nephropathy, Na-Li CT in NIDDM is apparently not associated with nephropathy; rather the ouabain-insensitive Na efflux appears to be correlated with the stages of nephropathy in NIDDM. The association suggests that the rate of ouabain-insensitive Na efflux may provide an index for assessing the degree of nephropathy in NIDDM patients.

An AM1 molecular orbital study of alpha-D-glucopyranose and beta-maltose: evaluation and implications

Chemical reactivity and other characteristics of alpha-D-glucopyranose and beta-maltose were evaluated within a semiempirical molecular orbital (AM1) framework. Theoretically generated structures compared well to those determined by X-ray crystallographic techniques. Calculations suggested that the secondary hydroxy functions (OH-2 and OH-3) of the mono- and di-saccharides were more acidic than the primary alcohol (OH-6), which is consistent with experimental findings. In addition, the enhanced reactivity of the OH-3 locus, which is observed upon OH-2 alkylation of the object sugars, was rationalized in terms of increased OH-3 acidity. The chemical behavior of the monomers examined may be insightful in explaining the reactivity of glucopyranose polymers.