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S C Yang

Publications and source records attributed to S C Yang.

At least 19 recordsLinked to original sources
PubMed2006

Effect of the intravesical resiniferatoxin instillation evaluated by the ice provocative urodynamic study.

STUDY DESIGN: Prospective urodynamic investigation before and after intravesical resiniferatoxin instillation treatment. OBJECTIVE: To evaluate the effectiveness of intravesical resiniferatoxin instillation for the treatment of neurogenic detrusor overactivity (NDO), using conventional and ice provocative urodynamic studies to monitor the activity of the unmyelinated C-fiber. SETTING: Spinal Cord Injury Unit, Yonsei Rehabilitation Hospital, Seoul, Korea. METHODS: A measure of 100 ml of resiniferatoxin solution, at a concentration of 100 nM diluted in 10% ethanol, was intravesically instilled into the bladder of 15 spinal cord injury patients with NDO. Conventional and ice provocative urodynamic studies were performed to evaluate the change in the involuntary detrusor activity, reflex volume, maximal bladder capacity, compliance, maximal detrusor pressure and reflex volume ratio 7 days before and 30 days after the instillation. RESULTS: Before the intravesical resiniferatoxin instillation, all patients exhibited NDO in both the conventional and ice provocative urodynamic studies, with a mean reflex volume ratio of 0.45+/-0.22. There was no significant change in the maximal bladder capacity, compliance and maximal detrusor pressure at the follow-up urodynamic study, but the reflex volume ratio was significantly increased (P<0.05) after the intravesical resiniferatoxin instillation. Among the 15 patients, three (20%) showed complete and nine (60%) partial suppression of the unmyelinated C-fiber activities. CONCLUSION: Intravesical resiniferatoxin instillation was partially controlled by the unmyelinated C-fiber activities, which were estimated by an ice provocative urodynamic study. Therefore, further studies on the optimal dosage and accurate indications for resiniferatoxin instillation are required.

Administration, Intravesical↗
PubMed2002

Clinical outcomes of pregnancy with one elevated glucose tolerance test value.

OBJECTIVE: To evaluate clinical outcomes of pregnancies with one elevated glucose tolerance test. METHODS: We performed a 50 g glucose challenge test (GCT) in 5,019 pregnant women at 24-28 weeks of gestation. In 1,170 women with plasma glucose levels over 130 mg/dl, a 100 g oral glucose tolerance test (OGTT) was performed at 28-32 weeks of gestation. During follow-up, 282 patients were lost and in the 888 cases that were followed-up, 189 were excluded because of GDM. Therefore 699 study patients were divided into four groups: No Elevated group (NE, N = 577) with all four normal 100 g OGTT values, and Groups 1 (N = 16), 2 (N = 35), and 3 (N = 71) with one elevated 100 g OGTT value after 1, 2 and 3 h, respectively. RESULTS: Poor maternal outcomes (NE group, Group 1, Group 2, Group 3: 17.5%, 37.6%, 22.9%, 25.3%) with pre-eclampsia, cesarean delivery for cephalopelvic disproportion, failure to progress, or fetal distress, was highest in Group 1 (odds ratio 2.94; 95% confidence interval 1.02-8.42). Poor perinatal outcomes (15.8%, 43.1%, 14.3%, 21.1%) with any one of the following; fetal distress, Apgar score of < 7 at 5 min, hypoglycemia, respiratory distress syndrome, small for gestational age and perinatal death, was also highest in Group 1 (odds ratio 4.24; 95% confidence interval 1.02-17.52). CONCLUSION: Pregnancies with one elevated glucose tolerance test value after 1 h exhibited increased adverse maternal and perinatal outcomes compared with the group with all normal OGTT values or the groups with an elevated glucose tolerance test value after 2 or 3 h.

Adult↗
PubMed2002

Haemophilus influenzae type b meningitis with subdural effusion: a case report.

Haemophilus influenzae type b causes invasive infection in children under 2 years of age. The disease may be complicated with hearing impairment, lowered learning ability, and other neurologic sequelae. The incidence of invasive H. influenzae type b has declined dramatically after the introduction of routine administration of protein-conjugated H. influenzae type b vaccine in the United States and some other countries. Because of its low incidence in Taiwan, many clinicians are not familiar with the initial symptoms and management of H. influenzae type b. This case report describes a 7-month-old H. influenzae type b meningitis patient who had initial presentations of prolonged intermittent fever and vague neurologic signs. Left peripheral facial palsy with hearing loss in left ear and bilateral frontal subdural effusion developed during the first 5 days of cefotaxime therapy. Betamethasone was then given for 4 days to relieve the severe inflammation. Drug-induced fever was observed after 11 days of antibiotic use and subsided with prednisolone treatment. Left ear hearing impairment persisted during the follow-up period, but the children did not experience other significant development delay.

Humans↗
PubMed2001

Collapsin response mediator protein-1 and the invasion and metastasis of cancer cells.

BACKGROUND: Numerous genetic changes are associated with metastasis and invasion of cancer cells. To identify differentially expressed invasion-associated genes, we screened a panel of lung cancer cell lines (CL(1-0), CL(1-1), CL(1-5), and CL(1-5)-F(4) in order of increasing invasive activity) for such genes and selected one gene, collapsin response mediator protein-1 (CRMP-1), to characterize. METHODS: We used a microarray containing 9600 gene sequences to assess gene expression in the cell panel and selected the differentially expressed CRMP-1 gene for further study. We confirmed the differential expression of CRMP-1 with northern and western blot analyses. After transfecting and overexpressing CRMP-1 in highly invasive CL(1-5) cells, the cells were assessed morphologically and with an in vitro invasion assay. We used enhanced green fluorescent protein-tagged CRMP-1 and fluorescence microscopy to localize CRMP-1 intracellularly. CRMP-1 expression in 80 lung cancer specimens was determined by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR). All statistical tests were two-sided. RESULTS: Expression of CRMP-1 was inversely associated with invasive activity in the cell panel, an observation confirmed by northern and western blot analyses. CRMP-1-transfected CL(1-5) cells became rounded and had fewer filopodia and statistically significantly lower in vitro invasive activity than untransfected cells (all P< .001). During interphase, CRMP-1 protein was present uniformly throughout the cytoplasm and sometimes in the nucleus; during mitosis, CRMP-1 was associated with mitotic spindles, centrosomes, and the midbody (in late telophase). Real-time RT-PCR of lung cancer specimens showed that reduced expression of CRMP-1 was statistically significantly associated with advanced disease (stage III or IV; P = .010), lymph node metastasis (N1, N2, and N3; P =.043), early postoperative relapse (P = .030), and shorter survival (P = .016). CONCLUSIONS: CRMP-1 appears to be involved in cancer invasion and metastasis and may be an invasion-suppressor gene.

Actins↗
PubMed2001

Cigarette smoking is strongly associated with mutation of the K-ras gene in patients with primary adenocarcinoma of the lung.

BACKGROUND: The majority of lung carcinoma cases occur in current or former smokers. K-ras gene mutations are common in lung adenocarcinoma and have been associated with cigarette smoking, asbestos exposure, and female gender. METHODS: In the current study, the authors examined the contribution of cigarette smoking to K-ras gene mutations in patients with primary lung adenocarcinoma. Smoking histories were obtained from 106 prospectively enrolled patients with primary adenocarcinoma of the lung. RESULTS: K-ras mutations were detected in the primary tumor using an allele-specific ligation assay. Ninety-two of the 106 patients (87%) with lung adenocarcinoma were smokers. Nonsmokers with this tumor were more likely to be women (11 of 14; 79%), whereas the majority of smokers (57%) were men. K-ras mutations were detected in 40 of 106 tumors (38%) and were significantly more common in smokers compared with nonsmokers (43% vs. 0%; P = 0.001). CONCLUSIONS: The results of the current study confirm and extend previous observations that smokers with adenocarcinoma of the lung are more likely to have K-ras mutant tumors compared with nonsmokers. The strong link between cigarette smoking and K-ras mutations in adenocarcinoma of the lung supports the role of specific tobacco carcinogens in the etiology of this malignancy.

Adenocarcinoma↗
PubMed2001

Global analysis of gene expression in invasion by a lung cancer model.

Metastasis is a complicated multistep process that involves interactions between cancer cells and their surrounding microenvironments. Previously, we have established a series of lung adenocarcinoma cell lines with varying degrees of invasiveness. Tracheal graft assay confirmed that cell lines with higher in vitro invasiveness had greater in vivo invasive potential. In this study, we used these model cell lines to identify invasion-associated genes using cDNA microarray with colorimetric detection. A more invasive subline, CL 1-5-F 4, derived from metastatic lung tumor of severe combined immunodeficient mice inoculated with CL 1-5 cells, was combined with CL 1-0, CL 1-1, and CL 1-5 in cDNA microarray screening. cDNA microarray membranes, each containing 9600 nonredundant expressed sequence tag clones, were used to identify differentially expressed genes in these cell lines. For statistical analysis, self-organizing map algorithm was performed to identify the expression patterns. Positive correlation between gene expression levels and cell line invasiveness was found in 2.9% of the 9600 putative genes. On the other hand, negative correlation was found in 3.3% of the genes. The trends of expression of some of the genes were also confirmed by Northern hybridization and flow cytometry. Our data demonstrated that genes related to cell adhesion, motility, angiogenesis, signal transduction, and some other expressed sequence tag genes may play significant roles in the metastasis process. These results substantiate the model system with which one can identify invasion-associated genes by using cDNA microarray and cancer cell lines of different invasiveness. This technique may allow us to explore complex interactions between multiple genes that orchestrate the process of cancer metastasis.

Adenocarcinoma↗
PubMed2001

Chromosomal alterations in lung adenocarcinoma from smokers and nonsmokers.

The etiology of lung tumors arising in nonsmokers remains unclear. Although mutations in the K-ras and p53 genes have been reported to be significantly higher in smoking-related lung carcinomas, in the present study we performed a more comprehensive analysis in search of additional genetic changes between lung adenocarcinoma from tobacco- and non-tobacco-exposed patients. We selected a matched cohort of 18 lifetime nonsmoking and 27 smoking patients diagnosed with primary adenocarcinoma of the lung and searched for chromosomal alterations in each tumor by testing normal and tumor tissue with 54 highly polymorphic microsatellite markers located on 28 different chromosomal arms. Allelic losses or gains at chromosomal arms 3p (37 versus 6%), 6q (46 versus 12%), 9p (65 versus 22%), 16p (28 versus 0%), 17p (45 versus 11%), and 19p (58 versus 16%) were present significantly more often in adenocarcinomas from smokers than from nonsmokers. Chromosomal arms showing allelic imbalance in lung tumors from nonsmokers were rare but occurred more often at 19q (22%), 12p (22%), and 9p (22%). The FAL (fractional allelic loss or gain) is defined as the percentage of chromosomal arm losses/gains among the total informative chromosomal arms. Tumors from smokers harbored higher levels of FAL (13 (48%) of 27 showed FAL > or = 0.3) compared with the lung tumors from the nonsmoker patients (2 (11%) of 18 showed FAL > or = 0.3; P = 0.02; odds ratio, 0.13; 95% confidence interval, 0.01-0.79). Our data demonstrate that widespread chromosomal abnormalities are frequent in lung adenocarcinoma from smokers, whereas these abnormalities are infrequent in such tumors arising in nonsmokers. These observations support the notion that lung cancers in nonsmokers arise through genetic alterations distinct from the common events observed in tumors from smokers.

Adenocarcinoma↗
PubMed2001

Trial of a novel synthetic sealant in preventing air leaks after lung resection.

BACKGROUND: Postoperative air leaks are a major cause of morbidity after lung resections. This study was designed to evaluate the efficacy and safety of a new synthetic, bioresorbable surgical sealant in preventing air leaks after pulmonary resection. METHODS: In a multicenter trial, 172 patients undergoing thoracotomy were randomized intraoperatively in a 2:1 ratio to receive surgical sealant applied to sites at risk for air leak after standard methods of lung closure (treatment group) or to have standard lung closure only (control group). The primary outcome variable was the percentage of patients free of air leakage throughout hospitalization. Secondary outcome variables were the control of air leaks intraoperatively and the time to postoperative air leak cessation. Time to chest tube removal, time to hospital discharge, and safety outcomes were also evaluated. RESULTS: Air leaks were identified before randomization in 89 of 117 patients in the treatment group and in 39 of 55 patients in the control group. Application of the sealant resulted in control of air leaks in 92% of treated patients (p < or = 0.001). A significantly higher percentage of treated patients than control patients remained free of air leaks during hospitalization (39% versus 11%, p < or =0.001). The mean times to last observable air leak were 30.9 hours in the treatment group and 52.3 hours in the control group (p = 0.006). In the treatment group, trends were observed for reduced time to chest tube removal and earlier discharge. No significant difference was identified in postoperative morbidity and mortality between the two groups. CONCLUSIONS: Air leaks after lung resection occur in most patients. The application of this novel surgical sealant appears to be effective and safe in preventing postoperative air leaks.

Acrylates↗
PubMed2001

Lung transplantation for primary and secondary pulmonary hypertension.

BACKGROUND: Single lung transplantation (SLT) and bilateral lung transplantation (BLT) are routinely performed in patients with primary pulmonary hypertension (PPH) and secondary pulmonary hypertension (SPH). It is unclear which procedure is preferable. We reviewed our experience with lung transplants for PPH and SPH to determine if any advantage exists with SLT or BLT for either PPH or SPH. METHODS: We reviewed the outcomes of all lung transplants performed for PPH or SPH for 4.5 years (July 1995 to January 2000). Survival was reported by the Kaplan-Meier method, and log rank analysis was used to determine significance. Statistical analyses of clinical data were performed using analysis of variance and chi2 analysis. RESULTS: A total of 57 recipients met criteria for pulmonary hypertension with a mean pulmonary artery pressure of greater than or equal to 30 mm Hg. There were 15 patients with PPH and 40 patients with SPH. There were 6 patients who had SLTs and 9 patients who had BLTs in the PPH group; and there were 9 patients who had SLTs and 21 patients who had BLTs in the SPH group. We found a survival advantage for PPH patients who underwent BLTs at all time points up to 4 years (100% vs 67%; p < or = 0.02). There was no clear advantage to SLTs or BLTs for SPH. At 4 years there was a trend toward improved survival with SLTs (91% vs 75%) in SPH patients with a mean pulmonary artery pressure less than or equal to 40 mm Hg (p < or = 0.11) with equivalent survival (80%) in patients with a mean pulmonary artery pressure greater than or equal to 40 mm Hg. There was also a trend toward improved survival in patients with a mean pulmonary artery pressure greater than or equal to 40 mm Hg (PPH and SPH) with BLTs (88% vs 62%; p = 0.19). The incidence of rejection, infection, and other complications was comparable between SLTs and BLTs in each group. CONCLUSIONS: We believe that BLT is the procedure of choice for PPH. The procedure of choice is less clear for SPH. Patients with SPH and a mean pulmonary artery pressure greater than 40 mm Hg may benefit from a BLT and those with a mean pulmonary artery pressure less than or equal to 40 mm Hg may do better with an SLT; however, no clear advantage is seen.

Adult↗
PubMed2001

Eosinophilic infiltrates in a pulmonary allograft: a case and review of the literature.

An unusual case of peribronchial eosinophilic infiltrates associated with peripheral blood eosinophilia in a lung transplant patient is described. The role that eosinophils play in lung allograft rejection is reviewed. Tissue eosinophils have been associated with acute pulmonary allograft rejection. Although, eosinophils in bronchoalveolar lavage fluid (BAL) have been observed in allograft rejection, this relationship is less well defined. The role of eosinophils in the pathophysiology of allograft rejection is unclear.

Cadaver↗
PubMed2001

Induction therapy in lung transplantation: a prospective, controlled clinical trial comparing OKT3, anti-thymocyte globulin, and daclizumab.

BACKGROUND: Because acute rejection is associated with inferior outcomes in lung transplantation, we have routinely employed OKT3, anti-thymocyte globulin (ATG), or daclizumab as adjuncts to reduce rejection. METHOD: We performed a 4-year prospective, controlled clinical trial of these 3 therapies to determine differences in post-operative infection, rejection, survival, and bronchiolitis obliterans syndrome (BOS). Eighty-seven consecutive lung transplant patients received OKT3 (n = 30), ATG (n = 34), and daclizumab (n = 23) as induction agents. The groups had similar demographics and immunosuppression protocols differing only in induction agents used. RESULTS: No differences were observed in immediate post-operative outcomes such as length of hospitalization, ICU stay, or time on ventilators. Twelve months post-transplant, OKT3 had more infections per patient than the other agents, a difference that only became significant 2 months post-operatively (p = 0.009). The most common infection was bacterial and OKT3 had more bacterial infections than any other agent. Daclizumab had more patients remain infection free in the first year (p = 0.02), having no fungal infections and a low rate of viral infections. No patient receiving daclizumab developed drug specific side-effects. Only those patients with episodes of acute rejection developed BOS. There were no significant differences in the freedom from acute rejection or BOS between the groups. The 2-year survival for the entire cohort was 68%, with no differences observed in patient survival. CONCLUSIONS: This study again reveals the importance of acute rejection in the subsequent development of BOS. Although daclizumab offers a low risk of post-transplant infection and drug specific side-effects, no drug is superior in delaying rejection or BOS or in prolonging long-term survival.

Adult↗
PubMed2001

An unusual case of fatal pulmonary allograft rejection.

This case report describes an atypical form of acute pulmonary allograft rejection that was refractory to conventional therapy. The rejection manifested primarily as interstitial lymphocytic infiltrates with little perivascular involvement. Despite aggressive therapy the patient died within 7 months of transplant. The timely recognition and treatment of unusual forms of allograft rejection is vital in the management of pulmonary transplant patients.

Adolescent↗
PubMed2001

The oxidation of cholesterol in the yolk of selective traditional Chinese egg products.

The yolks of traditional chicken egg products (Tiedan, Ludan, and Chayedan) and duck egg products (raw and cooked Xiandan, immersed and coated Pidan) were subjected to moisture, lipid, and thiobarbituric acid (TBA) determinations as well as cholesterol and cholesterol oxidation products (COP) analysis. The main COP detected for these egg products included 20-hydroxycholesterol and 7beta-hydroxycholesterol, other types of COP were not detected. The contents of COP formed in traditional egg products varied, depending upon the types of egg products. The cholesterol oxidation ratio for traditional Chinese chicken egg products ranged from 1.14 to 1.75%, whereas that for traditional Chinese duck egg products ranged from 1.18 to 1.90%. Those traditional egg products that required pickling in salt or alkaline, cooking, hot air drying, and exposure to oxygen and heat all produced COP.

Animals↗
PubMed2001

Detection of malignant cells in pleural fluid or ascites by CD44v8-10/CD44v10 competitive RT-PCR.

BACKGROUND: CD44 is a cell surface adhesion molecule which has been implicated in various biologic functions as lymphocyte homing and activation, cellular migration and extracellular matrix adhesion. Over-expression of CD44v8-10 has been found in several cancers and is considered to be associated with tumor progression and metastasis. Recently, a novel molecular method, CD44v8-10/CD44v10 competitive reverse transcription-polymerase chain reaction(RT-PCR) has been developed for detecting cancer cells over-expressing CD44v8-10. METHODS: We analyzed from benign and malignant pleural effusion and ascites by CD44 competitive RT-PCR and compared to the conventional cytology. RESULTS: The CD44 competitive RT-PCR analysis showed that all the 24 samples associated with benign disease presented a predominant expression of the CD44v10 transcript (v8-10/v10 ratio: 0.126-0.948), whereas 6 of 7 malignant pleural samples associated with cytology positive cancer expressed the CD44v8-10 transcript (v8-10/v10 ratio > 1.00). CONCLUSION: These results indicate that CD44 competitive RT-PCR assay is a useful and adjunct to cytological examination in cancer diagnosis, especially in detecting exfoliated cancer cells in pleural effusion.

Adult↗
PubMed2001

Retroperitoneoscopy assisted live donor nephrectomy: the Yonsei experience.

PURPOSE: Retroperitoneoscopy assisted live donor nephrectomy has become standard based on our experience with 103 consecutive cases operated on between January 1993 and May 2000. We describe the advantages of retroperitoneoscopy assisted compared to laparoscopic live donor nephrectomy. MATERIALS AND METHODS: After performing more than 1,200 cases of open live donor nephrectomy (S. C. Y.), we combined our experience with open and laparoscopic surgery to develop a specific technique of minilaparotomy live donor nephrectomy. Operations were performed by 1 senior surgeon and 1 assistant, with the help of specially designed piercing abdominal and peritoneal retractors. A 5 to 7 cm. transverse pararectal skin incision is made at the level of 10th rib and the abdominal muscles are split without division. A 10 mm. port is placed at the lower abdomen to allow for the telescope. The procedure is performed extraperitoneally, combining open and laparoscopic instruments under direct vision. Renal pedicles and ureters are ligated using laparoscopic clips and sutures. The kidney is removed via laparotomy and the wound is closed. RESULTS: Average operating time for the 103 live donor nephrectomies was 130 minutes (range 85 to 210), and there was no case of kidney loss, open surgical conversion or blood transfusion. Mean warm ischemia time was 2.3 +/- 1.2 minutes and average incision length was 6.5 cm. (range 5.1 to 7.0). Postoperative pain was minimal and analgesics were generally not required by postoperative day 2. Patients were fully ambulatory a mean 1.5 days (range 1 to 3.5) postoperatively. CONCLUSIONS: Retroperitoneoscopy assisted live donor nephrectomy is not only feasible, but reproducible. Any surgeon with previous experience with conventional open live donor nephrectomy can perform this hybrid, minimally invasive procedure.

Adult↗
PubMed2001

Fournier's gangrene--Taiwan experience.

BACKGROUND: Synergistic necrotizing fascitis of the scrotum, penis and perianal region was first described by Fournier in 1883. If not recognized early, this infectious process will extend along the fascia plane to the lower abdominal and back regions, causing severe morbidity and even mortality. METHODS: The records of 8 patients diagnosed of Fournier's gangrene were reviewed between 1988 and 2000. The sex, age, etiology, associated diseases, bacteriological studies and treatments were analyzed. RESULTS: The 8 patients were all males, age ranging from 42 to 78 years old, with average 55.1 years. Six patients were due to perianal abscess, one patient was a complication of hemorroidectomy, and one patient had traumatic injury of scrotum. Six patients had poor controlled diabetes mellitus, and there were two patients with cirrhosis of the liver and hepatoma, respectively. Even with aggressive treatments, two patients died; the other 6 recovered completely. The mortality rate was 25%. CONCLUSIONS: Fournier's gangrene is a not common but life-threatening disease which needs radical debridement and effective antibiotics to control the infection and early reconstruction with skin graft and myocutaneous flaps. Mortality is usually due to delayed diagnosis.

Adult↗
PubMed2001

Ventilatory defect in coal workers with simple pneumoconiosis: early detection of functional abnormalities.

Airway obstruction is a prominent feature in coal workers' pneumoconiosis (CWP). However, many patients with CWP have even demonstrated a normal forced vital capacity (FVC) and forced expiratory volume in 1s (FEV1). The purpose of this study was to evaluate the ventilatory defect by spirometry and search for parameters, other than FVC and FEV1, suitable for early detection of pulmonary impairment in CWP. A sample of 227 coal miners was selected from the medical clinics of two teaching hospitals. Maximal expiratory flow volume measurement and determination of functional residual capacity (FRC) and residual volume (RV) were carried out with an automated plethysmograph. The prevalence of airway obstruction (FEV1/FVC < 70%) in this sample of miners was 52.9% (120/227). There was a progression of functional impairment with the transition from category 0 to categories 2 and 3, no matter what the miners smoking habits. All of the 107 non-obstructed miners had a normal FVC and FEV1. However, the mean values for FEF25-75% (mean forced expiratory flow during the middle half of FVC) and Vmax50 (maximal expiratory flow rate at 50% FVC) were abnormally low, and RV was already elevated, in those non-obstructed subjects with category 1 simple pneumoconiosis. A borderline abnormally elevated FRC in the miners with radiological category 3 of CWP was also noted. We conclude that the Vmax50, FEF25-75%, and RV appeared to be the discriminative indices for detecting early ventilatory defect in non-obstructed patients with simple CWP. Further studies is still needed to clarify the cause of small airway dysfunction.

Adult↗