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Norris JD, Paige LA, Christensen DJ, Chang CY, Huacani MR, Fan D, Hamilton PT, Fowlkes DM, McDonnell DP. Peptide antagonists of the human estrogen receptor. Science 1999; 285:744-6. [PMID: 10426998 DOI: 10.1126/science.285.5428.744] [Citation(s) in RCA: 304] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Estrogen receptor alpha transcriptional activity is regulated by distinct conformational states that are the result of ligand binding. Phage display was used to identify peptides that interact specifically with either estradiol- or tamoxifen-activated estrogen receptor alpha. When these peptides were coexpressed with estrogen receptor alpha in cells, they functioned as ligand-specific antagonists, indicating that estradiol-agonist and tamoxifen-partial agonist activities do not occur by the same mechanism. The ability to regulate estrogen receptor alpha transcriptional activity by targeting sites outside of the ligand-binding pocket has implications for the development of estrogen receptor alpha antagonists for the treatment of tamoxifen-refractory breast cancers.
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Tsai WT, Chang CY, Ho CY, Chen LY. Simplified Description of Adsorption Breakthrough Curves of 1,1-Dichloro-1-fluoroethane (HCFC-141b) on Activated Carbon with Temperature Effect. J Colloid Interface Sci 1999; 214:455-458. [PMID: 10339388 DOI: 10.1006/jcis.1999.6192] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recovery of HCFC-141b, used as a major alternative solvent and foam-blowing agent for CFCs in industrial applications, has received great attention due to its gradual phase out. This paper describes an investigation of the adsorption breakthrough of HCFC-141b vapor on a commercial activated carbon. A simple theoretical model developed by Yoon and Nelson was applied to investigate the breakthrough behavior of HCFC-141b on an activated carbon column. The values of parameters k' (a rate constant) and tau (the time required for 50% adsorbate breakthrough) in the Yoon and Nelson model were determined at four different concentration levels (i.e., 399, 734, 1139, and 1954 ppmv) and five temperature ranges (i.e., 283, 293, 298, 303, and 313 K), respectively. These values were used to calculate the entire (0-100%) breakthrough curve (plot of percentage breakthrough versus time) regarding the adsorption of HCFC-141b on activated carbon columns. It was found that the calculated theoretical breakthrough curves are in high agreement with the corresponding experimental data. Also, the rate constant k' can be reasonably represented by the empirical Arrhenius equation. The results obtained are applicable for the scale-up design of adsorption columns in the HCFC adsorption on activated carbon adsorbent. Copyright 1999 Academic Press.
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Barenboim M, Chang CY, dib Hajj F, Young R. Characterization of the dual start motif of a class II holin gene. Mol Microbiol 1999; 32:715-27. [PMID: 10361276 DOI: 10.1046/j.1365-2958.1999.01385.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Holins are small membrane proteins that, at a genetically programmed time in a bacteriophage infective cycle, allow bacteriolytic enzymes, or endolysins, to escape to the periplasm and to attack the cell wall. Most holins fall into two sequence classes, I and II, based on the number of potential transmembrane domains (three for class I and two for class II). The prototype class I holin gene, S lambda, has a dual start motif and encodes not only the effector holin, Slambda105, but also an inhibitor, Slambda107, with a Met-Lys ...extension at the terminus. The prototype class II holin gene of phage 21, S 21, begins with the motif Met-Lys-Ser-Met ..., and a potential RNA secondary structure overlaps the Shine-Dalgarno sequence. Here, we demonstrate that (i) two protein products are elaborated from S 21, S2171 and S2168; (ii) the shorter product is required for lysis; (iii) the longer product, S2171, inhibits S 21 function; and (iv) the Lys-2 residue is important for the inhibitor function. Moreover, the RNA stem-loop structure is involved in the downregulation of S2171 synthesis. However, our results suggest that, in S 21, different segments of the single consensus Shine-Dalgarno sequence serve the two translational starts. These results show that the dual start motifs of class II holin genes are functionally homologous to those of class I holin genes.
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Wang SF, Cheng HC, Chang CY. Fat-suppressed three-dimensional fast spoiled gradient-recalled echo imaging: a modified FS 3D SPGR technique for assessment of patellofemoral joint chondromalacia. Clin Imaging 1999; 23:177-80. [PMID: 10506912 DOI: 10.1016/s0899-7071(99)00127-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Fast fat-suppressed (FS) three-dimensional (3D) spoiled gradient-recalled echo (SPGR) imaging of 64 articular cartilage regions in 16 patellofemoral joints was evaluated to assess its feasibility in diagnosing patellofemoral chondromalacia. It demonstrated good correlation with arthroscopic reports and took about half of the examination time that FS 3D SPGR did. This modified, faster technique has the potential to diagnose patellofemoral chondromalacia with shorter examination time than FS 3D SPGR did.
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Bläsi U, Fraisl P, Chang CY, Zhang N, Young R. The C-terminal sequence of the lambda holin constitutes a cytoplasmic regulatory domain. J Bacteriol 1999; 181:2922-9. [PMID: 10217787 PMCID: PMC93738 DOI: 10.1128/jb.181.9.2922-2929.1999] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The C-terminal domains of holins are highly hydrophilic and contain clusters of consecutive basic and acidic residues, with the overall net charge predicted to be positive. The C-terminal domain of lambda S was found to be cytoplasmic, as defined by protease accessibility in spheroplasts and inverted membrane vesicles. C-terminal nonsense mutations were constructed in S and found to be lysis proficient, as long as at least one basic residue is retained at the C terminus. In general, the normal intrinsic scheduling of S function is deranged, resulting in early lysis. However, the capacity of each truncated lytic allele for inhibition by the S107 inhibitor product of S is retained. The K97am allele, when incorporated into the phage context, confers a plaque-forming defect because its early lysis significantly reduces the burst size. Finally, a C-terminal frameshift mutation was isolated as a suppressor of the even more severe early lysis defect of the mutant SA52G, which causes lysis at or before the time when the first phage particle is assembled in the cell. This mutation scrambles the C-terminal sequence of S, resulting in a predicted net charge increase of +4, and retards lysis by about 30 min, thus permitting a viable quantity of progeny to accumulate. Thus, the C-terminal domain is not involved in the formation of the lethal membrane lesion nor in the "dual-start" regulation conserved in lambdoid holins. Instead, the C-terminal sequence defines a cytoplasmic regulatory domain which affects the timing of lysis. Comparison of the C-terminal sequences of within holin families suggests that these domains have little or no structure but act as reservoirs of charged residues that interact with the membrane to effect proper lysis timing.
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Chiou HJ, Chou YH, Liu CJ, Hsu CC, Tiu CM, Teng MM, Chang CY. Evaluation of ocular arterial changes in glaucoma with color Doppler ultrasonography. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 1999; 18:295-302. [PMID: 10206218 DOI: 10.7863/jum.1999.18.4.295] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The purpose of this study was to evaluate hemodynamic changes of the retrobulbar vasculature caused by different intraocular pressures with color Doppler ultrasonography. Fifty normal eyes in 25 patients, 13 patients with normal tension glaucoma, and 19 patients with acute glaucoma and increased intraocular pressure (greater than 30 mm Hg) were enrolled in this study. In 15 of 19 patients with acute glaucoma patients, follow-up color Doppler ultrasonography was also undertaken after laser peripheral iridectomy when the intraocular pressure had returned to normal. The peak systolic velocity, end diastolic velocity, resistive index, time average maximum velocity, and pulsatility index were compared in different vessels, including the central retinal artery, lateral posterior ciliary artery, medial posterior ciliary artery, and ophthalmic artery in each orbit. The peak systolic velocity, end diastolic velocity, and time average maximum velocity of the central retinal artery were significantly lower (P<0.01) in acute glaucoma patients than in the control group. The resistive index and pulsatility index of the central retinal artery were significantly higher (P<0.01) in acute glaucoma patients than in the control group. The end diastolic velocity of the lateral and medial posterior ciliary arteries was significantly lower in patients with acute glaucoma than in the control group, and the resistive index and pulsatility index of both of these arteries were significantly higher (P<0.001) in patients with acute glaucoma than in the control group. However, no statistical significantly differences were found in the peak systolic velocity or time average maximum velocity in either of the posterior ciliary arteries; similarly, no statistically significant differences were noted in any of the parameters in the ophthalmic artery between the control group and the group with acute glaucoma. The pulsatility index of the central retinal artery and of the lateral and medial posterior ciliary arteries was significantly lower (P<0.01) in acute glaucoma patients after laser therapy than in acute glaucoma patients before laser therapy. The resistive index of both posterior ciliary arteries was also significantly lower (P<0.004) in acute glaucoma patients after laser therapy than before laser therapy. All parameters for all vessels examined among the normal subjects, the patients with normal tension glaucoma, and the patients with acute glaucoma after laser therapy when the intraocular pressure had returned to normal showed no statistically significant differences. Color Doppler ultrasonography is a good modality for both imaging and studying the hemodynamics of the perioptic nerve vessels.
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Hessel AC, Vora N, Kountakis SE, Chang CY. Vascular lesion of the masseter presenting with phlebolith. Otolaryngol Head Neck Surg 1999; 120:545-8. [PMID: 10187954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
When evaluating an intramuscular soft tissue mass, a large differential diagnosis including both benign and malignant lesions must be considered. Because the treatment of these masses can range from simple observation to radical surgical excision, a minimally invasive but accurate method of diagnosis is desired. The workup should include radiographic imaging. MRI is the modality of choice for differentiating soft tissue lesions, although CT may be helpful in identifying calcifications such as a phlebolith. Although usually unnecessary, a sialogram can verify that a calcification lies within or outside the salivary ductal system. In most cases a biopsy specimen is required to confirm the diagnosis. However, if the imaging studies show characteristics consistent with a vascular soft tissue mass, the finding of a phlebolith is pathognomonic for a benign vascular lesion. If such a lesion is not causing significant cosmetic or functional disability, it can be observed without the need for invasive biopsy or treatment.
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Paige LA, Christensen DJ, Grøn H, Norris JD, Gottlin EB, Padilla KM, Chang CY, Ballas LM, Hamilton PT, McDonnell DP, Fowlkes DM. Estrogen receptor (ER) modulators each induce distinct conformational changes in ER alpha and ER beta. Proc Natl Acad Sci U S A 1999; 96:3999-4004. [PMID: 10097152 PMCID: PMC22409 DOI: 10.1073/pnas.96.7.3999] [Citation(s) in RCA: 324] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Estrogen receptor (ER) modulators produce distinct tissue-specific biological effects, but within the confines of the established models of ER action it is difficult to understand why. Previous studies have suggested that there might be a relationship between ER structure and activity. Different ER modulators may induce conformational changes in the receptor that result in a specific biological activity. To investigate the possibility of modulator-specific conformational changes, we have applied affinity selection of peptides to identify binding surfaces that are exposed on the apo-ERs alpha and beta and on each receptor complexed with estradiol or 4-OH tamoxifen. These peptides are sensitive probes of receptor conformation. We show here that ER ligands, known to produce distinct biological effects, induce distinct conformational changes in the receptors, providing a strong correlation between ER conformation and biological activity. Furthermore, the ability of some of the peptides to discriminate between different ER alpha and ER beta ligand complexes suggests that the biological effects of ER agonists and antagonists acting through these receptors are likely to be different.
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Chang CY. Pancreatic adenocarcinoma presenting as sinistral portal hypertension: an unusual presentation of pancreatic cancer. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 1999; 72:295-300. [PMID: 10907780 PMCID: PMC2578976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A rare syndrome, sinistral (left-sided) portal hypertension resulting from splenic vein thrombosis secondary to pancreatic adenocarcinoma of the tail is presented here. Pancreatic cancer is notorious for presenting with vague and nonspecific symptoms, including but not exclusively weight loss, abdominal pain, and anorexia with or without jaundice. However, physicians should be aware that in the presence of splenic vein thrombosis, this finding alone puts pancreatic cancer high on the differential diagnosis.
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Yang JL, Wang LC, Chang CY, Liu TY. Singlet oxygen is the major species participating in the induction of DNA strand breakage and 8-hydroxydeoxyguanosine adduct by lead acetate. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 1999; 33:194-201. [PMID: 10334621 DOI: 10.1002/(sici)1098-2280(1999)33:3<194::aid-em3>3.0.co;2-o] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
To investigate DNA damage induced by Pb2+ and its prevention by scavengers, we determined DNA strand breakage and the formation of 8-hydroxydeoxyguanosine (8-OHdG) in DNA using plasmid relaxation assay and HPLC with electrochemical detection, respectively. Lead acetate induced DNA strand breakage in 10 mM of Hepes buffer, pH 6.8, in a time- and dose-dependent manner. Compared with lead, zinc acetate did not significantly induce DNA breakage. The singlet oxygen scavengers NaN3 and 2,2,6,6-tetramethyl-4-piperidone (TEMP) inhibited lead-induced DNA breakage more efficiently than the hydroxyl radical scavengers mannitol and DMPO. Deuterium oxide (D2O), a singlet oxygen enhancer, potentiated lead-induced DNA breakage. At low ratios to Pb2+, NADPH, glutathione, and 2-mercaptoethanol enhanced lead-induced DNA breakage, whereas high ratios of these agents protected it. Catalase and superoxide dismutase (SOD) did not protect DNA breaks induced by Pb2+. Lead-induced DNA breakage was markedly enhanced by H2O2, and this induction was inhibited by NaN3, TEMP, EDTA, catalase, BSA, and glutathione. In contrast, mannitol and SOD potentiated Pb2+/H2O2-induced DNA breaks. The results indicate that singlet oxygen, lead, and H2O2 are all involved in the reaction system, whereas hydroxyl radical and superoxide did not. Lead could cause a small amount of 8-OHdG formation in calf thymus DNA and dose-dependently induced the formation of this adduct in the presence of H2O2. Singlet oxygen scavengers were more effective than hydroxyl radical scavengers in protection from lead/H2O2-induced 8-OHdG adducts. Taken together, these results suggest that lead may induce DNA damage through a Fenton-like reaction and that singlet oxygen is the principal species involved.
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186
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Chang CY, Cass SP. Management of facial nerve injury due to temporal bone trauma. THE AMERICAN JOURNAL OF OTOLOGY 1999; 20:96-114. [PMID: 9918183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
OBJECTIVE This article provides an overview of relevant data regarding the management of facial nerve injury due to temporal bone trauma. DATA SOURCES Sources used were relevant English language clinical and basic science publications. STUDY SELECTION A Medline search dating back to 1966 for articles concerning temporal bone trauma and facial nerve injury including both human and animal data was performed. Articles were included if they contained relevant data or were significant reviews on the subject. A retrograde bibliography search was then conducted to acquire any articles that may have been missed by the computerized search, including those papers published prior to 1966. DATA EXTRACTION The data from each paper were reviewed individually. DATA SYNTHESIS The data were not amenable to formal meta-analysis or valid data summarization. CONCLUSIONS Patients who should not require surgical intervention include those who have: documented normal facial nerve function after injury regardless of progression, presentation with incomplete facial nerve paralysis with no progression to complete paralysis, and degeneration <95% on ENoG. The remaining patients presumably have a poorer prognosis for return of facial nerve function although it remains unclear exactly how poor the return of function will be. Decompression surgery likely has a beneficial effect if performed within 14 days of injury, so those patients with expected poor natural outcomes may be offered this intervention. Late decompression surgery is not recommended. Late exploratory surgery is recommended only in those patients who do not experience adequate recovery of facial nerve function and likely require nerve repair. Despite the availability of a relatively large volume of published data, there remain many unanswered questions.
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Chen SS, Shao KN, Chiang JH, Chang CY, Lao CB, Lirng JF, Teng MM. Arachnoid granulations--computerized tomography and magnetic resonance imaging features: a case report. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1999; 62:46-50. [PMID: 10063712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
A 71-year-old woman had arachnoid granulations found in the straight and transverse sinuses on computerized tomography (CT) and magnetic resonance imaging (MRI). The arachnoid granulations appeared as low-density masses on CT. They gave low signals on T1-weighted MR images and high signals on T2-weighted images. Arachnoid granulations are usually of no clinical significance. They have characteristic CT and MRI manifestations and should not be mistaken for sinus thrombosis or intrasinus tumors.
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Chang CY, Cheung SW, Jackler RK. Meningiomas presenting in the temporal bone: the pathways of spread from an intracranial site of origin. Otolaryngol Head Neck Surg 1998; 119:658-64. [PMID: 9852544 DOI: 10.1016/s0194-5998(98)70030-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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189
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Wei J, Cheng KK, Tung DY, Chang CY, Wan WM, Chuang YC. Successful use of Phoenix-7 total artificial heart. Transplant Proc 1998; 30:3403-4. [PMID: 9838499 DOI: 10.1016/s0041-1345(98)01078-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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190
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Chao CS, Tung DY, Wei J, Chang CY, Chaung CY, Wan WM, Chang CH. Necrotizing soft tissue infection in heart transplantation recipients: two case reports. Transplant Proc 1998; 30:3347-9. [PMID: 9838477 DOI: 10.1016/s0041-1345(98)01056-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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191
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Chiou HJ, Chou YH, Cheng SP, Hsu CC, Chan RC, Tiu CM, Teng MM, Chang CY. Cubital tunnel syndrome: diagnosis by high-resolution ultrasonography. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 1998; 17:643-648. [PMID: 9771609 DOI: 10.7863/jum.1998.17.10.643] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The purpose of this study was to evaluate the morphologic changes in the ulnar nerve in cubital tunnel syndrome with high-resolution ultrasonography. The mean values of the short axis (cm) x long axis (cm) at the arm, epicondyle, and forearm levels were 0.057 +/- 0.01, 0.068 +/- 0.019, and 0.062 +/- 0.01 in control group; 0.069 +/- 0.04, 0.139 +/- 0.06, and 0.066 +/- 0.023 in the symptomatic side in patients with cubital tunnel syndrome; and 0.063 +/- 0.029, 0.068 +/- 0.029, and 0.057 +/- 0.012 in the normal side in patients with cubital tunnel syndrome. No significant difference was found in the area (short axis x long axis) of the ulnar nerve at the arm, epicondyle and forearm levels between the left and right ulnar nerve in the control group and between the control group and the normal side in symptomatic patients. However, the mean value of the area of the ulnar nerve at the epicondyle level in symptomatic patients was significantly larger than that of the control group and that of the contralateral side in patients, and the P value was less than 0.001. High resolution ultrasonography can detect morphologic changes in the ulnar nerve accurately, and it could therefore be useful as a screening and even follow-up modality in patients with cubital tunnel syndrome.
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192
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Chen JH, Wei J, Chang CY, Laiw RF, Lee YD. Studies on segmented polyetherurethane for biomedical application: effects of composition and hard-segment content on biocompatibility. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1998; 41:633-48. [PMID: 9697037 DOI: 10.1002/(sici)1097-4636(19980915)41:4<633::aid-jbm16>3.0.co;2-f] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Segmented polyetherurethane (SPEU) materials based on polytetramethylene oxide (PTMO, Mw 1000 and 2000) with various hard-segment contents were synthesized and their biocompatibilities studied via different tests. The static contact angle data reveal that the higher hard-segment-content SPEU material possesses a lower contact angle, implying that the surface of the higher hard-segment-content SPEU is more hydrophilic than its low hard-segment-content SPEU counterpart. The catalyst- and additive-free PTMO-based SPEU materials in this study possess neither a hemolytic nor a cytotoxic response that could be considered non toxic for biomedical applications. By using L-929 cell lines, a cell-seeding test indicated that the higher hard-segment-content SPEU material possesses quicker cell attachment and proliferation behaviors. In vitro platelet adhesion tests indicated that the lower hard-segment-content SPEU possesses less platelet adhesion than the high hard-segment-content SPEU material. Both ex vivo canine artery-artery (A-A) and arterio-venous (A-V) shunting tests revealed that the extent of platelet adhesion reaction is less for lower hard-segment content SPEU. In addition, the blood compatibility of SPEU material synthesized from PTMO 1000 excels over PTMO 2000 SPEU material by near the same levels as the hard-segment-content SPEU.
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193
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Wang YC, Jeng CM, Wu DY, Chang CY, Resnick D. Giant ossified cavernous hemangioma of an extremity associated with an equinovarus deformity. Skeletal Radiol 1998; 27:522-4. [PMID: 9809884 DOI: 10.1007/s002560050432] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A 39-year-old woman suffered from swelling and tenderness of the right leg for 31 years. Imaging studies showed a large soft tissue lesion on the right side extending from the proximal portion of the thigh to the ankle. She underwent several operations due to the leg mass and associated equinovarus deformity of the right ankle. The pathologic findings were those of an ossified cavernous hemangioma. This appears to be one of the largest hemangiomas to be reported. It revealed the three types of calcification characteristic of hemangiomas. Equinovarus deformity of the ankle caused by contracture of the calf in this case was probably related to repeated bleeding.
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194
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Ko JS, Shih C, Chang CY, Tiu CM, Penn IW, Wu JJ. Triangular fibrocartilage perforations with bilateral negative ulnar variant wrists: a case report. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1998; 61:556-9. [PMID: 9798306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Triangular fibrocartilage (TFC) constitutes the major part in the triangular fibrocartilage complex, which stabilizes the distal radioulnar joint and functions as a cushion for axial compression forces. Tears in the TFC are often encountered with positive ulnar variance and regarded as part of a degenerative process of the ulnocarpal joint. They are occasionally seen as the result of trauma and are less likely to be found in a young population, especially in those who are in the first two decades of life, without causative traumatic injury. We report the case of a 12-year-old boy with bilateral negative ulnar variances with incidental findings of TFC tears in both wrists. This is a rare case, as he had no history of a traumatic event.
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Abstract
Lipoblastomatosis is a rare benign lipomatous tumour of childhood and infancy, classically showing high signal identical to fat on T1 weighted images. A case of histologically proven lipoblastomatosis in an infant is presented, in which MRI showed low signal on T1 weighted images identical to that of muscle instead of high signal. This appearance has not been previously reported.
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Bayley H, Chang CY, Miller WT, Niblack B, Pan P. Caged peptides and proteins by targeted chemical modification. Methods Enzymol 1998; 291:117-35. [PMID: 9661148 DOI: 10.1016/s0076-6879(98)91010-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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197
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Maier A, Micka J, Miller K, Denko T, Chang CY, Nebert DW. Aromatic hydrocarbon receptor polymorphism: development of new methods to correlate genotype with phenotype. ENVIRONMENTAL HEALTH PERSPECTIVES 1998; 106:421-426. [PMID: 9637800 PMCID: PMC1533118 DOI: 10.1289/ehp.106-1533118] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Differential CYP1A1 inducibility, reflecting variations in aromatic hydrocarbon receptor (AHR) affinity among inbred mouse strains, is an important determinant of environmental toxicity. We took advantage of the Ahr polymorphism in C57BL/6 and DBA/2 mice to develop an oligonucleotide-hybridization screening approach for the rapid identification of DNA sequence differences between Ahr alleles. Oligonucleotides containing single-base changes at polymorphic sites were immobilized on a solid support and hybridized with C57BL/6 or DBA/2 AHR cDNA radiolabeled probes. The observed hybridization patterns demonstrate that this approach can be used to detect nucleotide differences in the Ahr coding region with very high accuracy. In parallel experiments, we used a yeast two-hybrid system to assess phenotypic differences in AHR function. AHR activation, as measured by beta-galactosidase reporter activity in Saccharomyces cerevisiae strain SFY526, was determined following treatment with varying doses of the AHR ligand beta-naphthoflavone (BNF). We found that the C57BL/6 AHR has about a 15-fold higher affinity for BNF than the DBA/2 AHR, in much better agreement with results reported for whole-animal studies than the values observed by in vitro ligand-binding assays. Using C57BL/6 and DBA/2 AHR chimeric proteins, we also confirmed the previously reported observation that an A375V change is principally responsible for the high- to low-affinity AHR phenotype. There has been no straightforward method to reliably and reproducibly phenotype large numbers of humans for CYP1A1 inducibility or AHR affinity. Screening human AHR cDNAs by oligonucleotide-hybridization and yeast two-hybrid methodologies will be invaluable for the rapid and unequivocal determination of changes in DNA sequence and receptor-ligand affinities associated with human AHR polymorphisms.
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198
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Wong HC, Peng PY, Han JM, Chang CY, Lan SL. Effect of mild acid treatment on the survival, enteropathogenicity, and protein production in vibrio parahaemolyticus. Infect Immun 1998; 66:3066-71. [PMID: 9632567 PMCID: PMC108314 DOI: 10.1128/iai.66.7.3066-3071.1998] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Vibrio parahaemolyticus is an important food-borne enteropathogen that encounters various adverse conditions in its native environment or during infection. Effects of mild acid treatment on survival under stress conditions, enteropathogenicity, and protein production in this pathogen were investigated. Logarithmically grown cells, at pH 7.5 shifted to pH 5.0 for 30 min, were more resistant to subsequent acid challenge at pH 4.4. A two-phase adaptive procedure (pH 5.8 for 30 min; pH 5.0 for 30 min) was better than a single-phase procedure for enhancing the acid tolerance of this pathogen. The acid-adapted cells were cross-protected against the challenges of low salinity and thermal inactivation. One-dimensional polyacrylamide gel electrophoresis revealed that proteins with molecular masses of 6.4, 9.0, 13.6, 16.3, 18.9, 22.9, 24.4, 28.3, 33. 9, 36.9, 41.2, 47.6, 58.1, 65.6, 80.5, 88.2, and 96.9 kDa were induced or significantly enhanced, while proteins of 25.3, 30.1, 30. 7, and 91.7 kDa were significantly inhibited. Two-dimensional polyacrylamide gel electrophoresis revealed that 20 species of proteins were induced or significantly enhanced, while 26 species were inhibited. In assays conducted using the suckling mouse model, enteropathogenicity of the acid-adapted cells was significantly enhanced in terms of intestine/body weight ratio and in vivo recovery of infected cells.
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Hwang JI, Chiang JH, Yu C, Cheng HC, Chang CY, Mueller PR. Pictorial review: Radiological diagnosis of duodenal abnormalities. Clin Radiol 1998; 53:323-32. [PMID: 9630268 DOI: 10.1016/s0009-9260(98)80002-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This article depicts the radiological findings of many common gastrointestinal entities. Specifically, examples of disease processes that affect the stomach, gall bladder, small intestine, pancreas and colon are shown. In most cases there is correlation between ultrasound, computed tomography (CT) and fluoroscopic imaging. The major emphasis of the article, however, is to demonstrate classic barium imaging of a large number of gastrointestinal disease processes.
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Wu JL, Hong JR, Chang CY, Hui CF, Liao CF, Hsu YL. Involvement of serine proteinase in infectious pancreatic necrosis virus capsid protein maturation and NS proteinase cleavage in CHSE-214 cells. JOURNAL OF FISH DISEASES 1998; 21:215-220. [PMID: 21361976 DOI: 10.1046/j.1365-2761.1998.00097.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
An investigation of virus-specific protein maturation in infectious pancreatic necrosis virus (IPNV) infected Chinook salmon embryo cells (CHSE-214) was undertaken. The precursor protein (pVP2-1) of the major mature capsid protein (VP2) was processed sequentially from pVP2-1 to pVP2-2 and VP2. Experiments using serine proteinase inhibitors showed that the maturation of the VP2 was blocked in the pVP2-1 post-translational cleavage steps. A protinin, a potent proteinase inhibitor, at 800 μg ml(-1) blocked pVP2-2 to VP2 and the cleavage of VP4 (28 kDa) to VP4-1 (25 kDa). Therefore, our data showed that the maturation of the capsid protein (VP2) and cleavage of VP4 (NS proteinase) can be blocked by serine proteinase inhibitors.
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