Biomedical subjects

C T Su

Publications and source records attributed to C T Su.

At least 19 recordsLinked to original sources

PubMed2003

The value of 18F-fluorodeoxyglucose positron emission tomography with the additional help of tumor markers in cancer screening.

Cancer screening is a major healthcare issue. Screening modalities are constantly changing due to improvements in technology. Whole body positron emission tomography (PET) with 18F-fluoro-2 deoxy-D-glucose (FDG) and the additional help of the serum levels of tumor markers have been considered as non-invasive methods for cancer screening in asymptomatic subjects. A total of 1283 subjects underwent whole-body FDG PET studies with the additional help of the serum levels of tumor markers in our center for cancer screening. The final diagnoses were confirmed by other imaging modalities or pathological findings in subjects with positive FDG-PET findings, and follow-up for at least 6 months were held in subjects with negative FDG-PET findings. Among a total of 18 (1.4%) subjects with cancers, FDG-PET detected cancers in 15 (1.2%) subjects but with false negative studies in 3 subjects with hepatoma (AFP = 129.6 ng/ml), prostate cancer (PSA = 25.1 ng/ml), and breast cancer (CEA and CA-153 were normal). False-positive FDG-PET studies were found in 24 (1.9%) subjects. However, none had abnormal serum levels of tumor markers. Whole body FDG-PET with the additional help of tumor markers could reduce the false negative and false positive results of FDG-PET only.

Adult↗

PubMed2002

Left cervical aortic arch with aneurysm and obstruction: three-dimensional computed tomographic angiography and magnetic resonance angiographic appearance.

Cervical arch is a rare congenital anomaly presumed to result from persistence of the third aortic arch and regression of the normal fourth arch. Rather rare is cervical aortic arch associated with aneurysm and obstruction, with eight known cases reported. Definitive diagnosis with a noninvasive imaging modality is desirable and very important to prevent the need for disaster intervention. We present two cases of a pulsatile mass in the left supraclavicular region. Three-dimensional computed tomographic angiography and magnetic resonance angiography clearly showed a left-sided cervical aortic arch (Haughton type D) with arch aneurysm and coarctation (pseudocoarctation).

Adolescent↗

PubMed2001

Validation of pulmonary venous obstruction by electron beam computed tomography in children with congenital heart disease.

The purpose of this study was to explore the useful imaging findings of electron beam computed tomography (EBCT) for diagnosing pulmonary venous obstruction (PVO) in children with congenital heart disease. From July 1995 to March 1998, 17 children (9 girls and 8 boys, aged 7 days to 14 years and 9 months [median 3 months]) with the diagnosis of PVO were enrolled in this study. All images were obtained by EBCT at the end-diastolic phase of the cardiac cycle after administration of intravenous iodinated contrast medium. The findings of 25 EBCT studies were retrospectively analyzed by 2 radiologists and were correlated with echocardiography, angiocardiography, and surgical findings. Main findings on EBCT for PVO were (1) structural narrowing, (2) thickened interlobular septa, (3) peribronchovascular cuffing, and (4) ground-glass opacity of the alveoli. Structural narrowing along the course of the pulmonary venous drainage was the most important finding in all examinations (25 of 25). Lung parenchymal changes secondary to PVO included thickened interlobular septa (17 of 25), peribronchovascular cuffing (15 of 25), and ground-glass opacity of the alveoli (8 of 25). Thus, the combination of these findings provides very useful data for the definitive diagnosis of PVO. Characteristic electron beam computed tomographic findings can validate suspected PVO noninvasively.

Adolescent↗

PubMed2001

Arterial blood pressure and blood lipids as cardiovascular risk factors and occupational stress in Taiwan.

BACKGROUND: This study is to determine whether occupational stress (defined as high psychological demands and low decision latitude on the job) is associated with increased blood pressure and abnormal level of blood lipids as cardiovascular risk factors. METHODS: We conducted a cross-sectional study at three work sites of 526 white-collar male workers aged 20 to 66 years without evidence of cardiovascular disease. Systolic, diastolic blood pressure, serum total, high-density lipoprotein cholesterol and plasma triglyceride were measured. Occupational stress index was derived from data collected in the job strain questionnaire. RESULTS: In multiple linear regression models, occupational stress index was significantly related to diastolic blood pressure and plasma triglyceride, after adjusting for age, education, smoking, and alcohol consumption. A higher occupational stress index was directly associated with higher systolic, diastolic blood pressure and higher level of plasma triglyceride. CONCLUSIONS: These data from a white-collar working population confirm independent relations between occupational stress defined in the job demand-control model and diastolic blood pressure observed in predominantly Western populations and extend the range of associations to plasma triglyceride than do previous studies.

Adult↗

PubMed2001

Neonatal lupus erythematosus in association with anti-RNP antibody: a case report.

Neonatal lupus erythematosus (NLE) is a syndrome with the manifestation of dermatological, cardiac, hepatic, or hematological abnormalities. Thrombocytopenia has been documented infrequently in association with congenital heart block or lupus dermatitis in NLE. However, isolated neonatal thrombocytopenia may be the only manifestation of NLE. The strong association with maternal anti-SSA/Ro antibodies suggests a role for these antibodies in the pathogenesis of NLE. There are some data to suggest that anti-SSB/La and, rarely, anti-RNP antibodies play an important pathological role in some cases of NLE. The manifestation of anti-RNP-positive NLE was somewhat atypical. We report a case of anti-RNP-positive NLE with the manifestation of thrombocytopenia. Anti-SSA/Ro antibodies, which were negative based on the use of immunodiffusion, did exhibit low titer when later tested by enzyme-linked immunoadsorbent assay (ELISA).

Antibodies, Antinuclear↗

PubMed2001

Association between job strain status and cardiovascular risk in a population of Taiwanese white-collar workers.

Using data from a survey of a white-collar working population in Taiwan (438 women, 526 men), the relation between job strain status and cardiovascular risk factors (high serum total cholesterol, low serum high-density lipoprotein (HDL) cholesterol, and high plasma fibrinogen) was examined. Job strain indicators, defined by Karasek's model, included psychological demand and decision latitude. Blood pressure, cholesterol and fibrinogen were analyzed as continuous variables, whereas psychological demand and decision latitude were dichotomized into 2 levels and job strain into 4 exposure categories. Plasma fibrinogen was significantly and positively associated with job strain status in both male and female workers and also with decision latitude in female workers only. No consistent association between job strain status and total serum and HDL cholesterol was detectable. In conclusion, plasma fibrinogen is a possible intermediate factor linking occupational stress to elevated cardiovascular risk.

Adolescent↗

PubMed2001

Preoperative diagnosis and localization of aldosterone-producing adenoma by adrenal venous sampling after administration of metoclopramide.

BACKGROUND AND PURPOSE: Adrenal venous sampling is the most reliable test to distinguish aldosterone-producing adenoma (APA) from idiopathic hyperaldosteronism (IHA). The diagnostic accuracy can be improved by administration of adrenocorticotropin to minimize pulsatile secretion of aldosterone. Metoclopramide (MCP), a dopamine antagonist, can increase aldosterone secretion promptly without affecting cortisol secretion. This study investigated the diagnostic accuracy of adrenal venous sampling after MCP injection for the preoperative diagnosis and localization of APA. METHODS: Prospective diagnosis and adrenalectomy was based on adrenal venous sampling in 23 patients with a diagnosis of primary aldosteronism. Plasma aldosterone concentrations from adrenal veins and the inferior vena cava were measured before and 30 minutes after intravenous administration of 10 mg MCP. The ratio of bilateral adrenal venous aldosterone concentrations after MCP was used for diagnosis as follows: a ratio greater than 5 indicated APA, less than 3 indicated IHA, and 3-5 indicated an intermediate diagnosis. RESULTS: Catheterization of the right adrenal vein was unsuccessful in three patients. Twelve of 13 patients with an aldosterone ratio greater than 5 after MCP underwent unilateral adrenalectomy, and APA was confirmed in 11 of these patients. One patient with an intermediate diagnosis also had surgically confirmed APA. Six patients had a ratio less than 3. Before MCP administration, 10 of 13 patients with APA had a ratio greater than 5, and three patients had a ratio between 3 and 5; one patient with IHA had a ratio greater than 5. MCP improved the diagnosis of APA to an accuracy of 92% (12/13). Correct diagnosis of APA based on computerized tomography (CT) was 85% (11/13). There was discordance between the findings of adrenal venous sampling and CT in four of 20 patients. CONCLUSIONS: Administration of MCP to stimulate aldosterone secretion during adrenal venous sampling can improve the accuracy of differential diagnosis between APA and IHA.

Adenoma↗

PubMed2000

Comparison of simultaneous dobutamine echocardiography and thallium-201 stress-reinjection single-photon emission computed tomography in predicting improvement of chronic myocardial dysfunction after revascularization.

Previous studies have shown that ultrasonic integrated backscatter is valuable in characterizing stunned myocardium. Recent investigations have demonstrated that resting cardiac cycle-dependent variation of integrated backscatter closely paralleled the contractile reserve in patients with chronic left ventricular ischemic dysfunction. The purpose of this study was to validate whether ultrasonic tissue characterization (UTC) compared with dobutamine stress echocardiography (DSE) and thallium-201 stress-reinjection single-photon emission computed tomography (Tl-SPECT) could predict reversible myocardial dyssynergy in patients with chronic coronary artery disease. Forty-eight patients with stable coronary artery disease underwent UTC, DSE, and Tl-SPECT simultaneously before successful coronary revascularization and were followed up with echocardiograms at rest >3 months later. Among the 58 investigated segments, the weighted amplitude, a composite parameter derived from the integrated backscatter power curve, was larger for those groups with greater functional recovery (p <0.001). For the persistent akinetic segments, the weighted amplitudes were small with large deviations of the nadir ratios that represented the asynchrony between the intramural contractile events and the global systole. Using the cut-off value 2.0 of the weighted amplitude, the sensitivity and specificity for predicting functional improvement after revascularization were both 82.8% (kappa = 0.66) and comparable to the sensitivity and specificity of DSE and Tl-SPECT. UTC, delineating the myocardial physical state and intramural contraction, can be a novel approach in predicting functional improvement of chronic dyssynergy after revascularization.

Adult↗

PubMed2000

Hemorrhagic disease in a newborn due to inadequate vitamin K prophylaxis: case report.

Vitamin K prophylaxis for all neonates has been recommended to prevent hemorrhagic disease of the newborn (HDN), but it is still an uncommon practice in most developing countries throughout the world. In the United States and Canada, where vitamin K injections continue to be recommended in the newborn period, HDN is not a major concern. The risk factors for HDN include inadequate vitamin K prophylaxis, exclusively breast-fed infants, diarrhea, and alternative causes of vitamin K deficiency, such as liver disease and cystic fibrosis. We present an exclusively breast-fed 3-week-old infant with diarrhea for 2 days who died from intracranial hemorrhage related to HDN despite having received a single intramuscular injection of 0.2 mg of vitamin K at birth. Hemorrhage in the infant from vitamin K deficiency should be a concern for pediatricians and obstetricians. We emphasize the importance of administering an adequate dosage of vitamin K for prevention of HDN, particularly in an exclusively breast-fed infant.

Breast Feeding↗

PubMed1999

High-resolution computed tomography of pulmonary alveolar microlithiasis.

Pulmonary alveolar microlithiasis (PAM) is a rare disease. It has been reported predominantly in Turkey. We report a case of PAM with characteristic high-resolution computed tomography (CT) findings. A 45-year-old Taiwanese woman had progressive difficulty in breathing for 7 years. Her chest radiographs showed diffuse high-density micronodules and reticular lines that obliterated the bronchovascular bundles and the margin of the heart and diaphragm. The micronodules were scattered throughout both lung fields with basal predominance. Examination of a transbronchial lung biopsy specimen showed PAM. High-resolution CT showed a unique and characteristic calcified reticular pattern and thickening of the interlobular septa of the lung parenchyma, with predominant basal and peripheral lung distribution. Reticulonodular changes of the interlobular septa and intralobular interstitial lines associated with subpleural air cysts and paraseptal emphysema were evident. These high-resolution CT findings are pathognomonic for PAM. Thus, lung biopsy may be avoided in the presence of this characteristic finding.

Calcinosis↗

PubMed1999

Impact of magnetic resonance imaging on the advancement of medicine.

Magnetic resonance (MR) imaging has had a significant impact in many areas of modern medicine. Because of its good image resolution, tissue characterization, and functional assessment of various organs and systems, MR imaging has become an important modern technology in clinical practice and medical research. MR imaging has great flexibility in viewing anatomic structures in arbitrary imaging planes. With ultrafast MR imaging techniques, images of areas of interest can be obtained in a very short time, with elimination of physiologic motion artifacts. MR angiography obviates the need for catheterization and provides highly detailed images of the vascular anatomy, even of structures as small as the coronary artery. MR cholangiopancreatography provides results comparable to those of endoscopic retrograde cholangiopancreatography in many hepatobiliary diseases. Functional MR imaging is a new tool to evaluate physiologic function. MR spectroscopy has been used to explore the metabolic activity of normal and diseased organs and structures. The applications of MR imaging in clinical medicine and biomedical research are expanding.

Abdominal Neoplasms↗

PubMed1998

Usefulness of electron beam computed tomography in children with heterotaxy syndrome.

Children with heterotaxy syndrome frequently have complex cardiac and noncardiac malformations requiring detailed diagnostic evaluation for management planning. Direct delineation of these structures by electron beam computed tomography (EBCT) is validated as a means of diagnosis. From July 1995 to March 1997, 32 patients (16 girls, 16 boys) with clinically impressed heterotaxy syndrome were enrolled in this study. After evaluation by echocardiography, EBCT studies were performed. Interpretation of cardiac anomalies was performed by sequential analysis based on these cross-sectional images. The diagnoses were subsequently confirmed by angiocardiography and surgical findings. Twenty-eight patients had bilateral trifurcated bronchi, and most of these (24 of 28) did not have a spleen. Four patients had bilateral bifurcated bronchi, 2 patients had polysplenia, and the other 2 patients had a lobulated single spleen. We found that laterality could be identified by EBCT in all patients. Comparison of diagnostic yield between echocardiography, catheterization, and EBCT showed that EBCT is superior to echocardiography and catheterization in demonstration of pulmonary venous anatomy and presence of a very small rudimentary ventricle. In addition, associated visceral, bronchopulmonary, mediastinal, and intracardiac anomalies could all be clearly delineated by EBCT at the same time. Thus, EBCT is a promising complementary modality for an overall understanding of heterotaxy syndrome.

Abnormalities, Multiple↗

PubMed1998

Calmodulin mediates calcium-dependent inactivation of N-methyl-D-aspartate receptors.

Ca2+ influx through N-methyl-D-aspartate (NMDA) receptors activates signal transduction pathways critical for many forms of synaptic plasticity in the brain. NMDA receptor-mediated Ca2+ influx also downregulates the gating of NMDA channels through a process called Ca2+-dependent inactivation (CDI). Recent studies have demonstrated that the calcium binding protein calmodulin directly interacts with NMDA receptors, suggesting that calmodulin may play a role in CDI. We report here that the mutation of a specific calmodulin binding site in the CO region of the NR1 subunit of the NMDA receptor blocks CDI. Moreover, intracellular infusion of a calmodulin inhibitory peptide markedly reduces CDI of both recombinant and neuronal NMDA receptors. Furthermore, this inactivating effect of calmodulin can be prevented by coexpressing a region of the cytoskeletal protein alpha-actinin2 known to interact with the CO region of NR1. Taken together, these results demonstrate that the binding of Ca2+/calmodulin to NR1 mediates CDI of the NMDA receptor and suggest that inactivation occurs via Ca2+/calmodulin-dependent release of the receptor complex from the neuronal cytoskeleton.

Actinin↗

PubMed1998

Comparison of S-T segment/heart rate slope with exercise thallium imaging and conventional S-T segment criteria in detecting coronary artery disease: effect of exercise level on accuracy.

The S-T segment/heart rate (ST/HR) slope has been proposed as a more accurate electrocardiographic criterion for the diagnosis of coronary artery disease, but studies comparing the diagnostic value of the ST/HR slope with exercise thallium imaging are scant. The aims of this study were to assess the diagnostic accuracy of the ST/HR slope, conventional S-T segment criteria and exercise thallium imaging in detecting coronary artery disease and to evaluate the effect of exercise level on the sensitivity and specificity of these three techniques. Ninety consecutive patients underwent treadmill testing and exercise thallium single-photon emission computed tomography (SPECT) simultaneously. All 90 patients also underwent coronary angiography within 1 month of the exercise test. We found that exercise thallium SPECT had a significantly higher diagnostic accuracy than either the ST/HT slope or conventional S-T segment criteria (thallium imaging 82%, ST/HR slope 67%, conventional S-T segment criteria 63%). The overall accuracy of the ST/HR slope was slightly but insignificantly greater than conventional S-T segment criteria (ST/HR slope 67%, conventional S-T segment criteria 63%; p = 0.639). In 50 patients with a lower exercise level, defined as not achieving 85% of their maximal predicted heart rate, the accuracy of the ST/HR slope was insignificantly greater (ST/HR slope 72%, conventional S-T segment criteria 66%; p = 0.517). In 40 patients with adequate exercise, the accuracy rate was the same (60%) for both the ST/HR slope and conventional S-T segment criteria. We conclude that exercise thallium imaging is more accurate than the ST/HR slope in diagnosing coronary artery disease and that the accuracy of the ST/HR slope is marginally better than conventional S-T segment criteria only in patients with a lower exercise level, and not in those with adequate exercise.

Cardiac Catheterization↗

PubMed1998

Seroprevalence of Toxoplasma gondii antibodies among Atayal aboriginal people and their hunting dogs in northeastern Taiwan.

Atayal aborigines, living at an altitude of 1,500-1,600 m in northeastern Taiwan, still hunt for wild animals with the help of hunting dogs. In this study, the latex agglutination test (LAT) was used to detect sera anti-toxoplasma antibodies in this community as a measure of their exposure to Toxoplasma gondii. The positive rates for sera anti-toxoplasma antibodies were 21.8% and 19.6%, respectively, in 422 Atayal and 51 hunting dogs tested. Neither of the positive rates were found to be significantly different between male (22.1%) and female Atayal (21.4%), or between humans (21.8%) and dogs (19.6%) (P > 0.05) when compared by the Chi-Squared test (chi 2-test). A significant difference was observed between the positive rates in adults (28.3%) and children (18.7%) (P < 0.05), and the age pattern of prevalence is consistent with an increasing duration of exposure to Toxoplasma gondii with age. The consumption of raw liver of wild animals or insufficiently cooked meat may be the major mode of transmission of toxoplasmosis in Atayal.

Adolescent↗

PubMed1998

Magnetic resonance angiography in the diagnosis of thoracic venous obstruction.

The aims of this study were to evaluate the diagnostic value of orthogonal magnetic resonance angiography (MRA) and to compare the results of MRA with those of digital subtraction venography (DSV) in thoracic venous diseases. Ten normal volunteers were evaluated using two-dimensional time-of-flight MRA in three orthogonal planes to determine the image quality of each venous segment. Twelve consecutive patients suspected of having thoracic venous disease were studied with both MRA and DSV. In the normal subjects, the plane perpendicular to the target vein provided the most consistent visualization. Using three orthogonal MRA images, a diagnostic-quality image was obtained in 175 (83%) of 210 venous segments in normal volunteers. In patients with thoracic venous obstructive disease, MRA was more effective than DSV in detecting total (84 vs 54), patent (56 vs 36), stenotic (13 vs 10), and obstructive (15 vs 8) venous segments, poststenotic or postobstructive veins (15 vs 10), thrombosis of the internal jugular vein (7 vs 2), intraluminal thrombus (5 vs 3), and azygos veins (12 vs 2). Using venous segments visible on DVS (n = 54) as the standard, the sensitivity and specificity of MRA were 94% and 100%, respectively, in detecting venous patency, and 100% and 98% in detecting complete venous obstruction. In the shoulder region, the sensitivity and specificity of MRA were 93% and 100%, respectively, in detecting venous patency, and 100% and 97% in detecting venous obstruction. We conclude that MRA with three orthogonal planes can provide relatively complete and reliable venous mapping, without the need for contrast medium.

Adult↗

PubMed1998

False-positive 2-[F-18]-fluoro-2-deoxy-D-glucose positron emission tomography studies for evaluation of focal pulmonary abnormalities.

Positron emission tomography (PET) with 2-[F-18]-fluoro-2-deoxy-D-glucose (FDG) can demonstrate the glucose metabolism characteristics of a lesion, which may be helpful in differentiating between benign and malignant focal pulmonary lesions. Malignant cells demonstrate higher glucose metabolic activity than benign lesions. However, some inflammatory processes also show significant FDG uptake. We present two cases where high FDG uptake was found in inflammatory lesions in the lungs. The first case was that of a 38-year-old woman with chronic cough for more than 20 years. FDG PET revealed a hypermetabolic lesion with a lesion-to-background ratio of 8.0 at the posterior aspect of the right middle lung. She underwent thoracotomy and tumor resection, and was diagnosed with cryptococcosis. The second case was that of a 72-year-old woman who had pulmonary tuberculosis previously with cavitation in the left lower lobe. She suffered from fever, chills and severe hemoptysis for several days before this admission. FDG PET revealed a hypermetabolic ring at the periphery of the cavity. The lesion-to-background ratio was 7.8. Echo-guided biopsy showed no evidence of malignancy. She was treated with antibiotics and the symptoms subsided gradually. Lung abscess complicating a pre-existing cavity was diagnosed. These two cases substantiate that positive FDG PET results should be interpreted with caution in differentiating benign from malignant pulmonary abnormalities, especially in regions with a high prevalence of granulomatous lesions.

Adult↗

PubMed1998

Magnetic resonance cholangiography for evaluation of cholestatic jaundice in neonates and infants.

Distinguishing extrahepatic biliary atresia from other causes of cholestasis in neonates and infants is important because surgical intervention before 2 months of age allows for long-term survival. The purpose of this prospective study was to evaluate the usefulness of magnetic resonance (MR) cholangiography in differentiating biliary atresia from other causes of cholestatic jaundice in neonates and infants. Nine anicteric infants (control group) aged 10 to 224 days (mean +/- SD, 8 +/- 65 days) and 15 neonates and infants with cholestatic jaundice, aged 22 to 142 days (mean +/- SD, 71 +/- 37) underwent MR cholangiography. The final diagnosis of extrabiliary atresia (6 patients) was based on laparotomy findings (4 patients) or autopsy (2 patients), while neonatal hepatitis (9 patients) was diagnosed according to the liver biopsy findings and clinical recovery during follow-up. Percutaneous liver biopsies were performed in all 15 patients. Results showed that the gall bladder and common bile duct (CBD) could be visualized using MR cholangiography in all patients in the control group. Nonvisualization of the CBD (6/6 patients) and demonstration of a small gall bladder (6/6 patients) characterized MR cholangiography findings in patients with biliary atresia. MR cholangiography failed to depict the CBD in one infant with hepatitis. We conclude that demonstration of the CBD by MR cholangiography in neonates and infants with cholestasis can be used to exclude the diagnosis of biliary atresia. In patients with cholestatic jaundice considered for exploratory laparotomy, preoperative MR cholangiography is recommended to avoid unnecessary surgery.

Biliary Atresia↗