176
|
Luo CB, Teng MM, Chen SS, Lirng JF, Chang FC, Guo WY, Chang CY. Imaging of invasiveness of pituitary adenomas. Kaohsiung J Med Sci 2000; 16:26-31. [PMID: 10741013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
The purpose of our study was to examine the tumor size, imaging invasiveness of the pituitary macroadenomas (PMA) and to evaluate the directions of PMA spread. One hundred and thirty-five patients with PMA were examined with MRI and/or CT for pre-operative evaluation. We retrospectively reviewed the CT and MRI to identify tumor size, extension and to evaluate the directions of tumor spread. One hundred and seventeen patients (87%) had suprasellar extension with compression of optic apparatuses, twelve patients (9%) had extension of tumor upward to hypothalamus and third ventricle. Infrasellar extension via the floor of the sella and sphenoid sinus was found in thirty-eight patients (28%), and further downward extension to ethmoid sinus, nasopharynx and/or skull base was depicted in five patients (4%). Twenty-two patients (16%) had lateral invasion to the cavernous sinus and associated cranial nerves. Temporal and frontal extensions were depicted in seven patients (5%) and six patients (4%), respectively. Five patients (4%) had posterior subtentorial extension to posterior fossa. Histologically, only two patients showed microscopic invasive features. There was no correlation between histologic features and imaging invasiveness. The PMA had the potential of multi-directional extension. This experience indicated any type of pituitary adenoma could invade surrounding structures. Suprasellar invasion was the most common direction of pituitary adenoma spread, followed by infrasellar, lateral, anterior and posterior routes.
Collapse
|
177
|
Chern MS, Ko JS, Tsai A, Wu MH, Teng MM, Chang CY. Aberrant left brachiocephalic vein: CT imaging findings and embryologic correlation. Eur Radiol 1999; 9:1835-9. [PMID: 10602959 DOI: 10.1007/s003300050931] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Computed tomography was utilized to evaluate aberrant left brachiocephalic vein (ALBCV), an infrequently discussed congenital vascular anomaly among Chinese people. Associated vascular variation and possible embryonic correlation are discussed. Since 1990, a total of 14 cases of ALBCV have been reported in patients receiving CT scan of chest, and was mainly an incidental diagnosis. One case was confirmed angiographically and two others were confirmed by magnetic resonance imaging. Emphasis was placed on the entry of the azygos vein into the superior vena cava (SVC), the length of the SVC, and the presence of other cardiovascular abnormalities. Of the 14 cases of ALBCV, the level of azygos vein entry was higher than the origin of the SVC in 7 cases: 4 were approximately the same level and 3 were lower. The average length of the SVC was approximately 5. 6 cm shorter than that of the general population, which is approximately 7.0 cm. Three cases had associated vascular anomaly. Most cases of ALBCV had azygos vein drainage level higher than or equal to the origin of the SVC. Right-sided aorta is one of the causes giving rise to the ALBCV during embryonic development. The CT scan remains a definitive diagnostic modality for ALBCV.
Collapse
|
178
|
Lin JJ, Yueh KC, Harn HJ, Chang DC, Chang CY, Yeh YH. Lack of association between deletion polymorphism of the ACE gene and ischemic vascular diseases in a Chinese population in Taiwan. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1999; 62:756-63. [PMID: 10575803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
BACKGROUND The association between deletion/insertion polymorphism of the angiotensin I-converting enzyme (ACE) gene and ischemic vascular diseases (IVDs) is still unclear. This study was designed to evaluate the role of ACE gene polymorphism in the pathogenesis of IVDs in a Chinese population living in Taiwan. METHODS A case-control study was carried out to examine the association of the ACE gene genotype and the allele frequency in 400 IVD patients, including 214 patients with ischemic cerebrovascular disease (ICVD) and 186 patients with ischemic heart disease (IHD), compared with 200 control individuals. RESULTS Although the patients with ICVD and IHD were found to have higher frequencies of the D/D genotype (22% and 43%) and the D allele (20% and 42%) than the controls (16% and 39%), the statistical differences were not significant, as shown by chi 2 analysis (p > 0.05). Upon further comparison of the frequencies of the D allele among the two sexes and different age subgroups, there was still no significant association. CONCLUSIONS Deletion polymorphism of the ACE gene was not associated with IVD in a Chinese population in Taiwan. The unique or synergistic effect of other genes that might contribute to the pathogenesis of IVDs needs further investigation.
Collapse
|
179
|
Chen SS, Chiang JH, Chang CY, Lao CB, Lirng JF, Teng MM. Giant cell reparative granuloma: a case report. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1999; 62:738-42. [PMID: 10533306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Giant cell reparative granuloma (GCRG) is an infrequent benign lesion with undetermined etiopathogenesis affecting the maxillary and mandibular bone and, rarely, the skull. It is also extremely rare in the sphenoid bone. GCRG is usually diagnosed by histologic examination of bone lesions. We report a case of GCRG originating from the sphenoid bone. Computerized tomography revealed an expansile lesion with thinning or destruction of the cortical bone. The lesion itself was slightly hyperdense with good but inhomogeneous contrast enhancement. Reported magnetic resonance image findings showed hyperintensity on both T1-weighted and T2-weighted images and variable contrast enhancement. Plain skull radiographs usually reveal a lytic lesion within the bone.
Collapse
|
180
|
Hsieh M, Li SY, Tsai CJ, Chen YY, Liu CS, Chang CY, Ro LS, Chen DF, Chen SS, Li C. Identification of five spinocerebellar ataxia type 2 pedigrees in patients with autosomal dominant cerebellar ataxia in Taiwan. Acta Neurol Scand 1999; 100:189-94. [PMID: 10478584 DOI: 10.1111/j.1600-0404.1999.tb00737.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES The autosomal dominant cerebellar ataxias (ADCAs) are a group of genetically diverse neurological conditions linked by progressive deterioration in balance and coordination. Spinocerebellar Ataxia Type 2 (SCA2) is one of the ADCAs and also belongs to a special group caused by the expansion of an unstable CAG repeat encoding a polyglutamine tract. We aimed to investigate the frequency of SCA2 mutation in the ataxia patients referred to the clinic. MATERIALS AND METHODS We screened 58 families with inherent cerebellar ataxia and 57 normal individuals by the use of radioactive genomic polymerase chain reaction (PCR) method. A simple non-radioactive PCR for rapid detection of the expanded SCA2 alleles via agarose gel electrophoresis was also employed. RESULTS Eight SCA2 affected patients and 1 at-risk individual in 5 unrelated SCA2 families were identified. The CAG repeats of normal alleles in the sample studied range in size from 16 to 30 repeat units, while those of SCA2 chromosomes are expanded to 34 to 49 repeat units. Our results also showed that unlike SCA 1 and SCA3/MJD, the size distribution of the normal alleles showed few polymorphisms, with the 22 repeat allele accounting for 90.1%. Homozygosity in normal individuals was 80.2%. No overlap in ataxin-2 allele size between normal and expanded chromosomes was observed. CONCLUSION This is the first report of the SCA2 gene distributions in the population of Taiwan. The SCA2 mutation accounts for 8.6% of ADCA type I families referred to us, intermediate between SCA1(1.7%) and SCA3/MJD (24%) of the ADCA type I families in our collection.
Collapse
|
181
|
Chen SS, Teng MM, Shao KN, Chiang JH, Chang CY, Lao CB, Lirng JF. Magnetic resonance imaging of unilateral olivary hypertrophy due to pontine tegmental hemorrhage: a case report. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1999; 62:648-51. [PMID: 10502858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Olivary hypertrophy (OH) is not a primary lesion but, rather, develops as a lesion of the Guillain-Morraret triangle, which is composed of the contralateral dentate nucleus, the ipsilateral red nucleus and the ipsilateral inferior olivary nucleus. OH is usually accompanied by palatal myoclonus or other involuntary movements such as extremity myorhythmia. One case of unilateral OH following ipsilateral pontine tegmental hemorrhage is presented. Magnetic resonance imaging (MRI) showed high signal intensity in the inferior olivary nuclei on T2- and proton-density-weighted images. Enlargement of the inferior olivary nuclei was also noted. MRI may currently be the only procedure capable of confirming the diagnosis.
Collapse
|
182
|
Chen SS, Shao KN, Chiang JH, Chang CY, Lao CB, Lirng JF, Teng MM. Intracranial pathology: comparison of intraoperative ultrasonography with computerized tomography and magnetic resonance imaging. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1999; 62:521-8. [PMID: 10462829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
BACKGROUND High-resolution, real time, intraoperative ultrasonography (IOUS) has been used in a number of cases in our neurosurgical department to identify, localize and characterize intracranial abnormalities. We compare the images of IOUS with those of computerized tomography (CT) and magnetic resonance imaging (MRI) in order to enhance our experience and confidence. METHODS IOUS images were compared with preoperative CT scans and/or MRIs in 30 intracranial masses. Tumor size and margin, echogenicity and edema were the features compared. RESULTS The images of IOUS, CT and MRI correlated closely except for images of primary gliomas. IOUS was more effective than CT and MRI in delineating the extent of a glioma, determining whether a lesion was cystic, with or without septation, or solid and in guiding surgical procedures. The contrast enhancement available with CT and MRI could not be demonstrated with IOUS. CONCLUSIONS IOUS provides exquisite detail of intracranial pathology as well as, or even better than, CT and MRI. Its application should be emphasized to minimize damage of normal brain tissue and increase the completeness of tumor resection.
Collapse
|
183
|
Chang CY, Peng YC, Hung DZ, Hu WH, Yang DY, Lin TJ. Clinical impact of upper gastrointestinal tract injuries in glyphosate-surfactant oral intoxication. Hum Exp Toxicol 1999; 18:475-8. [PMID: 10462358 DOI: 10.1191/096032799678847078] [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: 11/05/2022]
Abstract
Fifty patients with glyphosate-surfactant oral ingestion were studied with upper gastrointestinal (UGI) endoscopic grading using Zargar's modified grading system for mucosal corrosive injury. Esophageal injury was seen in 68% of the patients, gastric injury in 72%, and duodenal injury in 16%. There were no grade 3 injuries. The upper gastrointestinal tract injuries caused by glyphosate-surfactant were minor in comparison with those by other strong acids. The WBC count, amount of glyphosate-surfactant ingested, length of hospital stay and the occurrence of serious complications increased markedly in the group which had grade 2 esophageal injuries. Thus, the severity of the esophageal injuries may be a prognostic factor for the patient with glyphosate-surfactant ingestion. The UGI endoscopy may be indicated for grading esophageal injury in patients who have ingested glyphosate-surfactant in amounts greater than 100 ml. Physicians should pay more attention to the patients with grade 2 or 3 esophageal injuries to prevent serious complications and to provide aggressive supportive care.
Collapse
|
184
|
Chiou HJ, Chou YH, Wu JJ, Hsu CC, Tiu CM, Chang CY, Yu C. Alternative and effective treatment of shoulder ganglion cyst: ultrasonographically guided aspiration. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 1999; 18:531-535. [PMID: 10447077 DOI: 10.7863/jum.1999.18.8.531] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The therapeutic effect of ultrasonographically guided aspiration of a ganglion cyst of the shoulder is evaluated. Fifteen patients (nine male, six female) with chronic shoulder pain were enrolled in this study. Each patient was referred to rule out rotator cuff lesion. The ultrasonographic examination showed an anechoic cystic lesion in the shoulder region in every patient and abnormality of the rotator cuff in only four patients. Under ultrasonographic guidance, an 18 gauge needle was inserted into the cyst to aspirate the fluid. Initial sonographic imaging showed the cyst, which appeared as a localized fluid accumulation and was located between the deltoid muscle and the subscapularis tendon in seven patients, between the deltoid muscle and the biceps tendon in one patient, below the coracoacromial ligament in five patients, and over suprascapular notch area in one patient. The ganglion cysts ranged in size from 3.5 to 30 mm. The amount of aspirated fluid in each cyst varied from 0.4 to 12 ml (mean, 2.6 ml +/- 3.1) with a clear or light yellowish color and a jelly-like appearance. No major complications occurred during or after this procedure. The symptom (pain) was improved after sonographically guided aspiration in each patient. Follow-up study showed complete relief of pain in four patients, marked improvement in nine patients, and mild improvement but still persistent shoulder pain in two patients. Duration of follow-up study ranged from 2 to 24 months (mean, 6.4 months +/- 6.9). The success rate for sonographically guided aspiration was 86% on the basis of marked symptom improvement or relief. Ultrasonographically guided aspiration of shoulder ganglion cysts is an effective procedure in the management of shoulder pain caused by ganglion cysts.
Collapse
|
185
|
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.
Collapse
|
186
|
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.
Collapse
|
187
|
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.
Collapse
|
188
|
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.
Collapse
|
189
|
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.
Collapse
|
190
|
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.
Collapse
|
191
|
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.
Collapse
|
192
|
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.
Collapse
|
193
|
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.
Collapse
|
194
|
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.
Collapse
|
195
|
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.
Collapse
|
196
|
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.
Collapse
|
197
|
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]
|
198
|
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]
|
199
|
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]
|
200
|
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.
Collapse
|