251
|
Yu L, Nagasue N, Yamaguchi M, Chang YC. Effects of castration and androgen replacement on tumour growth of human hepatocellular carcinoma in nude mice. J Hepatol 1996; 25:362-9. [PMID: 8895016 DOI: 10.1016/s0168-8278(96)80123-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND/AIMS Previous clinical investigations suggest that androgen and its receptor (AR) may play an important role in the growth of hepatocellular carcinoma. Few studies are available concerning the effect of androgen manipulation on the growth of AR-positive hepatocellular carcinoma in vivo. METHODS AR-positive (SM10) and AR-negative (SM2) sublines derived from a human hepatocellular carcinoma line KYN-1 were implanted subcutaneously in the lower abdomen of nude mice. The tumour size and expression of proliferating cell nuclear antigen and Lewis Y antigen were examined in intact males, castrated males, intact females, and castrated males with androgen replacement. AR of the tumour was measured with binding assay, ultracentrifugation, and Western blotting. RESULTS The growth of SM10 was significantly better in intact males and castrated males with 5a-dihydrotestosterone injection than in intact females and castrated males. Castration did not suppress the growth of SM2. The tumour AR level was reduced by castration but maintained by the hormone substitution. Although proliferating cell nuclear antigen expression was closely associated with tumour growth, Lewis Y antigen expression did not differ among the groups. CONCLUSIONS These data may indicate that this hepatocellular carcinoma subline (SM10) is androgen-responsive and that androgen ablation can cause the inhibition of the tumour growth, which might be due to decreased proliferative and not increased apoptotic activities. In addition, such androgen-stimulated tumour growth seems to be mediated through AR.
Collapse
|
252
|
Lo I, Kao MJ, Hsu WC, Kuo KK, Chang YC, Weng HM, Chiang JC, Tsay SF. Photoinduced electron coupling in delta -doped GaAs/In0.18Ga0.82As quantum wells. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:4774-4779. [PMID: 9986439 DOI: 10.1103/physrevb.54.4774] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
253
|
Chu H, Chang YC. Theory of optical spectra of exciton condensates. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:5020-5028. [PMID: 9986466 DOI: 10.1103/physrevb.54.5020] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
254
|
Shy SW, Lee WH, Chang YC, Wu W. A solitary congenital self-healing histiocytosis. Report of a case and review of the literature. Pathol Res Pract 1996; 192:869-74; discussion 875-6. [PMID: 8897523 DOI: 10.1016/s0344-0338(96)80064-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Congenital self-healing histiocytosis (CSHH), and especially the solitary variant, is a rare primary skin disorder. We report on a newborn with a congenital solitary ulcerated skin nodule. Extracutaneous involvement was not found. A skin biopsy was performed at the age of 44 days and revealed a dense dermal infiltrate of large histiocytic cells. Immunohistochemical study revealed that the cells of the dermal infiltrate were Langerhans' cells which were strongly positive for S- 100 and negative for lysozyme, leukocyte common antigen and alpha-1-antichymotrypsin. The skin lesion involuted spontaneously over the next month without any treatment. The clinical, histopathological and immunohistochemical results fulfilled the criteria of solitary CSHH. We herein report the first case of CSHH in Taiwan and the twelfth case of solitary CSHH in the world.
Collapse
|
255
|
Shih JY, Wang HC, Chang YL, Chang YC, Lee YC, Yang PC. Echogenic floating spherules as a sonographic sign of cystic teratoma of mediastinum: correlation with CT and pathologic findings. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 1996; 15:603-605. [PMID: 8839409 DOI: 10.7863/jum.1996.15.8.603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
256
|
Chen YW, Yip PK, Jeng JS, Hwang BS, Chang YC, Lin WH. Reverse jugular flow in a case of thrombosis of the brachiocephalic vein with an artificial arteriovenous fistula. Angiology 1996; 47:699-702. [PMID: 8686965 DOI: 10.1177/000331979604700710] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Thrombosis of the thoracic inlet veins following placement of a central venous catheter is a well-known complication, and several findings have been reported by color Doppler sonography. However, reverse jugular flow resulting from this complication is rarely mentioned and should be differentiated from another complication of iatrogenic arteriovenous fistula between neck vessels. The authors here describe a uremic patient with an artificial arteriovenous fistula in the forearm complicated with thrombosis of the ipsilateral brachiocephalic vein. Factors permitting the differential diagnosis by coloer Doppler sonography and clinical conditions are proposed.
Collapse
|
257
|
Chang YC, James RB. Theoretical studies of carrier transport in HgI2. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:14200-14211. [PMID: 9983216 DOI: 10.1103/physrevb.53.14200] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
258
|
Chang YC, Penoyer LA, Kwon-Chung KJ. The second capsule gene of cryptococcus neoformans, CAP64, is essential for virulence. Infect Immun 1996; 64:1977-83. [PMID: 8675296 PMCID: PMC174025 DOI: 10.1128/iai.64.6.1977-1983.1996] [Citation(s) in RCA: 189] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The extracellular polysaccharide capsule produced by Cryptococcus neoformans is essential for its pathogenicity. We have isolated and characterized a gene, (AP64, which is required for capsule formation. An encapsulated strain created by complementation of the cap64 mutation produced fatal infection of mice within 25 days, while the cap64 acapsular strain was avirulent. Gene deletion of CAP64 from a wild-type strain resulted in the loss of capsule as well as virulence. Contour-clamped homogeneous electric field gel analysis indicates that CAP64 is located on chromosome III which is different from the localization of another capsule-related gene, CAP59. The nonlinkage between CAP64 and CAP59 was also supported by classical recombinational analysis. Database searches did not reveal any sequence with high similarity to CAP64. We also found that the CAP64 locus is contiguous to a convergently transcribed gene which has significant similarity to the gene encoding the yeast proteasome subunit, PRE1. The distance between the cDNA ends of these two genes is only 22 bp. This study confirms the previous molecular genetic evidence that capsule is an essential factor for the virulence of C. neoformans in the murine model.
Collapse
|
259
|
Chang YC, Patz EF, Goodman PC. Pneumothorax after small-bore catheter placement for malignant pleural effusions. AJR Am J Roentgenol 1996; 166:1049-51. [PMID: 8615239 DOI: 10.2214/ajr.166.5.8615239] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE The objective of this study was to evaluate the incidence and significance of pneumothorax after small-bore chest tube placement for symptomatic malignant pleural effusions. SUBJECTS AND METHODS Over a 2-year period, 90 patients with a known primary malignant tumor and symptomatic pleural effusion were referred to the radiology service at Duke University Medical Center. All patients underwent placement of a small-bore chest tube with fluid drainage in preparation for intrapleural sclerotherapy. Two of these patients were excluded because of coexisting empyema (n=1) and thoracentesis (n=1). The remaining 88 patients (30 men and 58 women; 26-86 years old [mean, 60 years old], who had 90 chest tubes placed, formed our study group. The incidence, duration, and clinical significance of their pneumothoraces and the amount of pleural effusion drained were recorded. RESULTS Among the 88 patients with 90 chest tubes, 27 patients with 28 chest tubes (31%) were found to have pneumothorax after the procedure. For 23 patients with 24 chest tubes, pneumothorax was evident on chest radiographs taken immediately after tube insertion and fluid drainage. Four patients with four chest tubes were found to have pneumothorax on chest radiographs taken the next day. No significant difference in the amount of fluid drained during the procedure was noted for patients with or without pneumothorax (831 ml versus 853 ml). No relationship between the size of each pneumothorax and the size of each drainage catheter was seen. The duration of pneumothorax ranged from 2 hr to 18 days (average, 3.5 days). Resolution of pneumothorax was seen in 22 (79%) of 28 cases; the remaining six cases of pneumothorax (21%) were stable, and the patients showed eventual fluid reaccumulation after chest tube removal and no sclerotherapy. No patient developed tension pneumothorax, respiratory distress, or other complications. CONCLUSION Pneumothorax should be recognized as a common finding after chest tube placement and immediate fluid drainage for malignant pleural effusions. We suggest that this finding is related to rapid removal of fluid from a relatively stiff, noncompliant lung. Patients whose lungs do not fully re-expand in several days will probably not benefit from sclerotherapy. Their tubes may be removed without risk of an enlarging tension pneumothorax.
Collapse
|
260
|
|
261
|
Lee WT, Wang PJ, Liu HM, Young C, Tseng CL, Chang YC, Shen YZ, Lee CY. Acute disseminated encephalomyelitis in children: clinical, neuroimaging and neurophysiologic studies. ZHONGHUA MINGUO XIAO ER KE YI XUE HUI ZA ZHI [JOURNAL]. ZHONGHUA MINGUO XIAO ER KE YI XUE HUI 1996; 37:197-203. [PMID: 8755175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Nine patients below 20 years of age (4 males and 5 females), who were diagnosed to have acute disseminated encephalomyelitis (ADEM) by clinical findings and magnetic resonance imaging (MRI), were reviewed retrospectively. They ranged from 4 months to 20 years of age with an average of 8.6 years. Seven patients (78%) received neurophysiological studies, which included electroencephalography, multimodality evoked potentials (EPs), nerve conduction velocity and/or F-wave measurement. The presentation symptoms were mainly headache, vomiting, consciousness change and motor deficits. Seven (78%) of nine patients had symptoms preceded by fever or upper respiratory tract infections; one (11%) was preceded by trivalent mumps, measles, rubella vaccination and no definite predisposing factor was found in another. Computed tomography (CT) scans were abnormal in five (71 %) of seven children, while MRI showed multiple lesions in seven (78%) of nine children. The lesions in MRI were mainly in the brainstem (n = 6), basal ganglion (n = 5), thalamus (n = 4), periventricular white matter (n = 4) and cerebellum (n = 4). EPs disclosed spinal cord involvement in all patients who received the examination. Peripheral neuropathy was disclosed in one patient. It was concluded that associated radiculoneuropathy is possible in patients with ADEM. Both MRI and neurophysiologic studies are complementary for diagnosis of ADEM.
Collapse
|
262
|
Peng SF, Chang YC, Su CT, Yang PC, Yao YT, Huang KM, Hsu CY. High-resolution computed tomography in pulmonary lymphangio(leio)myomatosis and pulmonary tuberous sclerosis. J Formos Med Assoc 1996; 95:399-402. [PMID: 8688707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We report two cases where high-resolution computed tomography (HRCT) assisted in the diagnosis of a patient with lymphangioleiomyomatosis and a patient with pulmonary tuberous sclerosis. HRCT was used in both cases where the chest radiographs and conventional computed tomographic scans appeared relatively normal but the conditions were strongly suspected.
Collapse
|
263
|
Abstract
Integration of reverse transcribed viral DNA of HIV into host chromosomes is mediated by the viral enzyme, integrase. This enzymatic activity can be monitored in vitro by integration of a small labeled DNA (donor) into a second unlabeled DNA (target). The methodology usually involves isotope labeling and gel electrophoresis. To simplify the measurement, a method mimicking enzyme-linked immunosorbent assay (ELISA) procedures was developed. Fragments of DNA were adsorbed directly on 96-well plates and used as the target DNA. The donor was a synthetic 21-bp DNA duplex of HIV-1 U5 LTR; biotin was incorporated into the 5' end of one strand whose two nucleotides at the 3' end were specifically removed during the integration. As a result of integration, the biotin-labeled donor DNA was joined with the target DNA and became immobilized on plates. These integration products were then measured by binding of avidin-alkaline phosphatase on plates. The method is simple and straightforward and can easily be adapted for high throughput screening of integrase inhibitors.
Collapse
|
264
|
Chien CT, Fu TC, Lai YL, Chang YC, Chen CF. Renal neural response to ischemic renal failure in chronic hypoxic rats. JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM 1996; 58:11-7. [PMID: 8740654 DOI: 10.1016/0165-1838(95)00109-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
This report was designed to assess response of the renal nerve activity (RNA) during and after renal ischemia in chronic hypoxic rats. Hypoxia was induced by placing the female Wistar rats in an altitude chamber set at 5500 m for 4 weeks. Simultaneous recordings of left renal efferent (RENA) and afferent (RANA) nerve activity were performed in each pentobarbital-anesthetized rat throughout the experiment. Ischemic renal failure was induced by complete occlusion of the left renal artery for 45 min. During renal arterial occlusion (RAO), RENA gradually decreased while RANA enhanced initially and then this decreased gradually in both sea level (SL) controls and chronic hypoxic (high-altitude; HA) rats. During 45 min of reperfusion, RENA depressed more in comparison with RANA in both groups of animals. In addition, RANA returned to baseline level in SL rats, while it remained elevated in HA rats. In the second experiment, six groups of renal ischemic rats were challenged by rapid intravenous infusion of 10 ml of saline, and urine was collected for 90 min from the left ureter. Baseline RENA was low in rats 4 h after RAO of SL (4SL) and of HA (4HA) groups. The effects of saline loading on RENA and RANA were different in HA and SL rats. Saline loading significantly decreased RENA but increased RANA more in SL rats. Following saline loading, RENA in 4SL and 4HA rats, as well as animals 24 h after RAO of SL (24SL) and HA (24HA) were comparable to their respective SL or HA animals. In 4SL rats, RANA was significantly enhanced, and remained elevated during saline loading and the recovery period. In 4HA, 24HA and 24SL rats, RANA reduced significantly during saline loading, then its activity returned to the baseline value. The insulted kidneys showed increased renal excretion of water and sodium in 4SL and 4HA rats. Urinary excretion reduced significantly in 24SL rats but was almost normal in 24HA rats. These results indicate that a decrease in RENA may play a protective role in response to renal ischemia in both SL and HA rats. In response to renal ischemia and saline loading, different alterations of RANA in SL and HA rats may reflect a beneficial mechanism located in the hypoxia-pretreated kidney.
Collapse
|
265
|
Chang YC, Patz EF, Goodman PC, Granger CB. Significance of hemoptysis following thrombolytic therapy for acute myocardial infarction. Chest 1996; 109:727-9. [PMID: 8617083 DOI: 10.1378/chest.109.3.727] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
PURPOSE To describe the occurrence, cause, and significance of hemoptysis following thrombolytic therapy for acute myocardial infarction. PATIENTS AND METHODS We retrospectively reviewed 2,634 patients presenting with acute myocardial infarction who received thrombolytic therapy to determine the incidence of hemoptysis. Chart and radiographic review included the type, dose, and route of thrombolytic therapy. In addition, the onset, duration, and severity of hemoptysis were recorded and correlated with radiographic and bronchoscopic findings. RESULTS Eleven patients (0.4%) developed hemoptysis following administration of thrombolytic therapy for an acute myocardial infarction. The duration and severity had a wide range, although no patient had significant hemodynamic compromise. The source of hemoptysis was identified in only one patient who had a tongue laceration following cardiopulmonary resuscitation, and blood was seen within the oropharynx and trachea. No definitive cause was identified in all other patients. There was no correlation between the different types or doses of thrombolytic therapy and the duration or severity of hemoptysis. Chest radiographs were nonspecific and demonstrated resolution within 11 days following hemoptysis. CT of the thorax in one patient and bronchoscopy in two patients confirmed chest radiographic findings and in no patient was an underlying pulmonary abnormality identified. CONCLUSIONS Pulmonary hemorrhage and hemoptysis are unusual complications of thrombolytic therapy in patients with acute myocardial infarction. Although hemoptysis may be the first indicator of an underlying pulmonary abnormality, we found no case in which a significant abnormality was unmasked. This study suggests that follow-up chest radiographs are recommended and further evaluation may be unnecessary if complete resolution is demonstrated.
Collapse
|
266
|
Liou HH, Chen RC, Tsai YF, Chen WP, Chang YC, Tsai MC. Effects of paraquat on the substantia nigra of the wistar rats: neurochemical, histological, and behavioral studies. Toxicol Appl Pharmacol 1996; 137:34-41. [PMID: 8607139 DOI: 10.1006/taap.1996.0054] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Effects of paraquat on the substantia nigra of the male Wistar rats we re studied pharmacologically by a intracerebral injection of paraquat. The neurochemical, morphological, and behavioral changes observed after a unilateral intranigral injection of paraquat (1-5 microgram) were as follows: (1) neurochemically, paraquat caused dose-dependent depletion of dopamine in the ipsilateral striatum starting 2 weeks after treatment; this effect was long-lasting and irreversible. The ipsilateral striatal dopamine level in animals treated with 3 microgram paraquat was even decreased by 91.5%. (2) Morphologically, 2 microgram of paraquat produced marked loss of Nissl substances and prominent glial reaction in the substantia nigra, while 3 microgram of paraquat caused a severe loss of neurons. (3) Behaviorally, paraquat caused a vigorous rotational behavior in rats contralateral to the lesioned side in response to apomorphine administration (0.5 mg/kg, sc). This effect was dose-dependent and lasted for the entire 16-week experimental period. Taken together, these data indicate that intranigrally injected paraquat may possess marked neurotoxicity and induce degeneration of the rat nigrostriatal dopaminergic system.
Collapse
|
267
|
Chang YC, Huang CC, Liu CC. Frequency of linear hyperechogenicity over the basal ganglia in young infants with congenital rubella syndrome. Clin Infect Dis 1996; 22:569-71. [PMID: 8852982 DOI: 10.1093/clinids/22.3.569] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Five young infants with congenital rubella syndrome (CRS) underwent cranial ultrasonographic examinations and/or computed tomographic examinations. Only two of these infants were small for their gestational age, and none of them were microcephalic at birth. Deafness and ocular lesions were found in four patients, and congenital heart disease was found in three. All had abnormal ultrasonographic findings: linear-shaped hyperechogenicity over the basal ganglia was noted for five patients, periventricular punctate hyperechogenicity was noted for three, and subependymal cysts were observed in two. Follow-up ultrasonograms for two of the patients showed progressively enlarging hyperechogenic lesions. Calcification was found in both patients examined by means of computed tomography. All patients became microcephalic, with profound global developmental delay. Intracranial calcifications are common findings in patients with CRS. Ultrasonography should be performed for high-risk neonates, regardless of their symptoms. The finding of linear hyperechogenicity over the basal ganglia should prompt a search for all congenital infections, including CRS.
Collapse
|
268
|
Chang YC, Kadokura H, Yoda K, Yamasaki M. Secretion of active subtilisin YaB by a simultaneous expression of separate pre-pro and pre-mature polypeptides in Bacillus subtilis. Biochem Biophys Res Commun 1996; 219:463-8. [PMID: 8605010 DOI: 10.1006/bbrc.1996.0256] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Alkaline elastase YaB, produced by alkalophilic Bacillus YaB, is an extracellular serine protease having 55% homology to subtilisin BPN' and thus could be called subtilisin YaB. It is synthesized as a 378-amino acid preproenzyme and secreted into the culture medium as a 265-amino acid mature protease. To examine if the pro-peptide of subtilisin YaB functions in trans to guide the folding of secreted subtilisin YaB in vivo, we made genes encoding the pre-pro, pro and pre-mature portions and placed them under the control of the spac-1 promoter on a multi-copy plasmid. When simultaneous expression in Bacillus subtilis of both the pre-pro and pre-mature genes was induced with 0.5 mM isopropyl-1-thio-beta-D-galactopyranoside (IPTG), protease activity was detected in the medium. On the other hand, we could not detect protease activity when the expression of either the pre-mature gene alone or both the pro and pre-mature genes was induced. From these results, we concluded that the pro region functions in trans and outside the cells for the proper folding and activation of the enzyme.
Collapse
|
269
|
Pedersen FB, Chang YC. Energy levels of one and two holes in parabolic quantum dots. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:1507-1516. [PMID: 9983613 DOI: 10.1103/physrevb.53.1507] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
270
|
Chang YC, Reid JF. RGB calibration for color image analysis in machine vision. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 1996; 5:1414-1422. [PMID: 18290059 DOI: 10.1109/83.536890] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A color calibration method for correcting the variations in RGB color values caused by vision system components was developed and tested in this study. The calibration scheme concentrated on comprehensively estimating and removing the RGB errors without specifying error sources and their effects. The algorithm for color calibration was based upon the use of a standardized color chart and developed as a preprocessing tool for color image analysis. According to the theory of image formation, RGB errors in color images were categorized into multiplicative and additive errors. Multiplicative and additive errors contained various error sources-gray-level shift, a variation in amplification and quantization in camera electronics or frame grabber, the change of color temperature of illumination with time, and related factors. The RGB errors of arbitrary colors in an image were estimated from the RGB errors of standard colors contained in the image. The color calibration method also contained an algorithm for correcting the nonuniformity of illumination in the scene. The algorithm was tested under two different conditions-uniform and nonuniform illumination in the scene. The RGB errors of arbitrary colors in test images were almost completely removed after color calibration. The maximum residual error was seven gray levels under uniform illumination and 12 gray levels under nonuniform illumination. Most residual RGB errors were caused by residual nonuniformity of illumination in images, The test results showed that the developed method was effective in correcting the variations in RGB color values caused by vision system components.
Collapse
|
271
|
Chen YW, Jeng JS, Liu HM, Yip PK, Hwang BS, Lin WH, Chang YC, Tu YK. Diagnosis and follow-up of carotid-cavernous fistulas by carotid duplex sonography and transcranial color Doppler imaging. ULTRASOUND IN MEDICINE & BIOLOGY 1996; 22:1155-1162. [PMID: 9123639 DOI: 10.1016/s0301-5629(96)00152-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
To investigate the suitability of extracranial carotid duplex (ECD) and transcranial color Doppler imaging (TCDI) in the diagnosis and follow-up of treatment in patients with carotid-cavernous fistulas (CCF), combined ECD and TCDI examinations were studied in seven patients with traumatic CCF. According to angiography, four patients had direct CCF, two indirect CCF and one both direct and indirect CCF. In ECD, hemodynamic parameters of the feeding artery showed an abnormally increased flow volume and decreased resistivity indices in five direct CCFs from the internal carotid artery and one indirect CCF from the external carotid artery. Direct visualization of the CCF was achieved in patients with direct CCF only, and revealed itself as a heterogeneous mosaic flash resulting from high flow velocities and turbulence. Patterns of venous drainage were detected via the transorbital and transforaminal windows in seven and five patients (four direct and one indirect CCF patients), respectively. These abnormal findings were improved or even normalized after successful treatment. In conclusion, combined ECD and TCDI examinations appear to be useful for the diagnosis and follow-up of CCF.
Collapse
|
272
|
Su IJ, Huang LM, Wu SJ, Jin YT, Kao YF, Tsai TF, Lee JY, Hsu YH, Hsiao CH, Chang YC, Wang YW, Lee CY. Detection and sequence analysis of a new herpesvirus-like agent in AIDS and non-AIDS Kaposi's sarcoma in Taiwan. J Formos Med Assoc 1996; 95:13-8. [PMID: 8640089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
A new herpesvirus-like DNA sequence (KSHV) has been recently identified in Kaposi's sarcoma from acquired immunodeficiency syndrome (AIDS) and non-AIDS patients. In order to verify the role of this new viral agent in Taiwan, a series of Kaposi's sarcoma specimens obtained from AIDS and non-AIDS patients in three medical centers representing different geographic locations of Taiwan were surveyed. A total of seven specimens from AIDS patients and 22 specimens from non-AIDS patients were tested for the presence of this herpesvirus-like agent by polymerase chain reaction (PCR) using the published Kaposi's sarcoma 330-233 primers. The tumor DNA was also tested for cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpes-virus type 6 (HHV-6). The Kaposi's sarcoma specimens from AIDS and non-AIDS patients were positive for KSHV except in one case. Only occasional specimens were positive for CMV and EBV, with a slightly higher positive rate for HHV-6 in AIDS and non-AIDS patients. Cloning and sequence analysis of the PCR products from two cases of Kaposi's sarcoma (one each for AIDS and non-AIDS) revealed only minor differences in this DNA sequence, as compared with the published data from north America. These results further support the assumption that this new KSHV is strongly associated with Kaposi's sarcoma in AIDS and non-AIDS patients in Taiwan.
Collapse
|
273
|
Chang YC, Wickes BL, Kwon-Chung KJ. Further analysis of the CAP59 locus of Cryptococcus neoformans: structure defined by forced expression and description of a new ribosomal protein-encoding gene. Gene 1995; 167:179-83. [PMID: 8566774 DOI: 10.1016/0378-1119(95)00640-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Cryptococcus neoformans (Cn) produces an extracellular polysaccharide capsule that is an essential factor for virulence. We previously isolated a gene, CAP59, which is necessary for capsule formation. To dissect the functional region of CAP59, we placed it under control of the Cn GAL7 promoter (pGAL7). Among the several pGAL7::CAP59 fusion constructs, only the one containing the entire open reading frame of CAP59 was able to complement the acapsular phenotype under galactose induction. A missense mutation in the coding region abolished complementation by the fusion construct. We also found that the CAP59 locus is contiguous to a convergently transcribed L27 ribosomal protein-encoding gene (CL27). The distance between the cDNA ends of these two genes is only 25 bp. CL27 has two introns near its N terminus. The translated CL27 protein is 183 amino acids (aa) in length with an estimated molecular mass of 20 kDa, and the first 34 aa at the N terminus may be a targeting peptide for mitochondria. A high degree of restriction-fragment-length polymorphism was detected in the DNA sequence containing CAP59 and CL27.
Collapse
|
274
|
Chang YC, Wang JD. Cumulative injury rate and potential workdays and salary lost. Scand J Work Environ Health 1995; 21:494-503. [PMID: 8824756 DOI: 10.5271/sjweh.66] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
OBJECTIVES The purpose of this study was to examine alternative methods for quantifying occupational injuries and to estimate the costs of foregone earnings due to these injuries. METHODS A model based on the three possible outcomes of occupational injuries (premature death, permanent disability, and temporary dysfunction) was proposed, and several new indices were developed to measure the frequency and severity of occupational injuries. In the calculations, the human capital method was employed to measure potential salary lost due to occupational injury. An example was adopted from a steel corporation to demonstrate these indices. RESULTS The cumulative injury rates, based on age and duration of employment, represented the average cumulative risk of acquiring occupational injuries by lifetime work duration and by employment duration, respectively. The severity index revealed the rate of estimated potential workdays lost by incorporating both the age at which an injury occurred and the severity weighting factors of various disabilities into the formula. After the estimated potential workdays lost was divided by the total employees' potential affordable workdays, the proportion of potential workdays lost showed a result that adjusted for the varied age distribution in each year implicitly. The potential loss in salary calculated the foregone earnings of occupational injuries, which could be considered as a lower limit of the monetary cost estimated by the willingness-to-pay method. CONCLUSIONS Such indices supplement disabling frequency and severity rates. They cannot only be applied to occupational safety monitoring, but also to the policy-making process in occupational safety and health.
Collapse
|
275
|
Chang YC, Nair MG, Nitiss JL. Metabolites of daidzein and genistein and their biological activities. JOURNAL OF NATURAL PRODUCTS 1995; 58:1901-1905. [PMID: 8691210 DOI: 10.1021/np50126a016] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A number of metabolites of daidzein and genestein have been synthesized and their biological activities determined. Equol [3], 5,7,4'-trihydroxyisoflavan [5], 4,7,4'-trihydroxyisoflavan [6], dihydrodaidzein [8], and dihydrogenistein [9] were synthesized either from daidzein [1] or genistein [2] by hydrogenation. Similarly, the derivatives 4, 7, and 11 were synthesized from 3, 6, and 10, respectively. During acetylation and nmr experiments, 9 was converted to a novel enol intermediate [10]. Antifungal, antibacterial, mosquitocidal, nematocidal, and topoisomerase inhibition activities of these compounds were evaluated, with equol [3] being the most active of the compounds tested against topoisomerase I.
Collapse
|