Biomedical subjects

W J Chen

Publications and source records attributed to W J Chen.

At least 37 records · Page 2Linked to original sources

PubMed2001

Acute melatonin and para-chloroamphetamine interactions on pineal, brain and serum serotonin levels as well as stress hormone levels.

para-Chloroamphetamine, an amphetamine analog, alters serotonergic neurochemistry. In previous reports, melatonin (MEL), when administered with other amphetamine analogs, altered the decline in serotonin content produced by these analogs. The present studies assessed the effects of various doses of melatonin and p-chloroamphetamine on serotonin levels in numerous brain regions in male rats. Melatonin (10, 25 or 50 mg/kg, s.c.) and p-chloroamphetamine (3 or 5 mg/kg, s.c.) were administered and, 3 h later, brain samples and serum were collected. Serotonin levels in the serum and various regions of the brain were assayed using high-performance liquid chromatography. Melatonin in combination with a high dose of p-chloroamphetamine (5 mg/kg) produced cumulative deficits in serotonin levels in the serum. However, serotonin levels in the pineal, cortex or brain stem in all combined melatonin and p-chloroamphetamine groups were not significantly different from groups that received p-chloroamphetamine alone. Serum adrenocorticotropin (ACTH) and corticosterone levels were significantly elevated in the melatonin and p-chloroamphetamine combined groups, suggesting that animals receiving both treatments were more stressed than control animals or animals receiving melatonin or p-chloroamphetamine alone. These results indicate that melatonin does not alter p-chloroamphetamine-induced deficits in central serotonin levels. The increased serum adrenocorticotropic hormone, corticosterone and serotonin levels observed following melatonin and p-chloroamphetamine treatment suggest that this combination may have adverse peripheral effects.

Adrenocorticotropic Hormone↗

PubMed2001

Vascular endothelial growth factor 189 mRNA isoform expression specifically correlates with tumor angiogenesis, patient survival, and postoperative relapse in non-small-cell lung cancer.

PURPOSE: The purpose of this study was to evaluate the correlation between the expression of four different vascular endothelial growth factor (VEGF) mRNA isoforms (VEGF121, VEGF165, VEGF 189, and VEGF206) and the clinicopathologic characteristics, tumor angiogenesis, and outcome of patients with non-small-cell lung cancer. PATIENTS AND METHODS: We examined the expression of four different VEGF mRNA isoforms in 57 non-small-cell lung cancers using reverse transcriptase polymerase chain reaction and the tumor angiogenesis using immunohistochemical staining. RESULTS: All 57 lung cancer samples expressed the VEGF121, VEGF165, and VEGF189 mRNA isoforms, and three expressed the VEGF206 mRNA isoform. A high tumoral VEGF189 mRNA isoform expression ratio was associated with a high intratumoral microvessel count (P = .013), short survival (< 24 months; P = .001), and early postoperative relapse (< 12 months; P = .001). Survival and postoperative relapse time were significantly shorter in patients with a high compared with a low tumor VEGF189 mRNA isoform expression ratio (P = .0001 and P = .0086, respectively, log-rank test). In contrast, the VEGF165 and VEGF 206 mRNA isoform expression ratios showed no statistical correlation with tumor angiogenesis, postoperative relapse time, or survival. A high VEGF121 mRNA isoform expression ratio was associated with short survival (< 24 months) and early relapse (< 12 months). Multivariate analysis showed that VEGF 189 mRNA isoform expression, microvessel count, and nodal status were the most important independent prognostic factors for patient survival and postoperation recurrence. CONCLUSION: The VEGF189 mRNA isoform expression ratio shows a greater correlation with tumor angiogenesis, postoperative relapse time, and survival than do the expression ratios for the VEGF121, VEGF165, and VEGF206 mRNA isoforms and can be used as a prognostic indicator for patients with non-small-cell lung cancers.

Carcinoma, Non-Small-Cell Lung↗

PubMed2001

Serum levels of transforming growth factor beta1 in patients with breast cancer.

HYPOTHESIS: Transforming growth factor beta1 (TGF-beta1) may be related to breast cancer progression. DESIGN: Prospective study. SETTING: University hospital. PATIENTS: Sixty consecutive patients with invasive breast cancer undergoing surgery were prospectively included and evaluated. The control group consisted of 14 patients with benign breast tumors (7 with fibrocystic disease and 7 with fibroadenoma). INTERVENTION: Venous blood samples were collected before the surgery. Sera were obtained by centrifugation and stored at -70 degrees C until assayed. Serum concentrations of TGF-beta1 were measured by quantitative sandwich enzyme immunoassay. Data on primary tumor stage, age, estrogen receptor status, lymph node status, distant metastases, and TNM staging (according to the Union Internationale Contre le Cancer) were reviewed and recorded. MAIN OUTCOME MEASURES: Measurements of preoperative serum TGF-beta1 levels in patients with breast cancer. RESULTS: The mean +/- SD value of serum TGF-beta1 in patients with invasive breast cancer was 498.7 +/- 249.7 pg/mL and in the control group was 495.2 +/- 225.5 pg/mL (P =.96). However, there were significantly higher serum levels of TGF-beta1 in patients with more advanced lymph node status (P =.04), more advanced TNM stage (P =.005), and poorer histological grade (P =.02). In multivariate analysis, TNM staging (P =.02) was demonstrated to be the independent factor related to significantly higher serum levels of TGF-beta1. CONCLUSIONS: Patients with more advanced TNM stages were shown to have higher serum TGF-beta1 levels. Thus, serum TGF-beta1 levels may reflect the severity of invasive breast cancer.

Adult↗

PubMed2001

Value of chest sonography in the diagnosis and management of acute chest disease.

PURPOSE: The aim of this study was to investigate the value of chest sonography in the diagnosis and management of patients with chest radiograph opacities in an emergency department. METHODS: Seventy-eight patients with acute chest complaints whose chest radiographs showed opacities underwent chest sonography. The initial diagnosis (based on clinical manifestations and the chest radiograph), the sonographic diagnosis (before any invasive procedures), and the final diagnosis were compared. The impact of chest sonography on the management of patients with chest opacities was also analyzed. RESULTS: The initial diagnosis was in concordance with the final diagnosis in 60 (77%) of the 78 patients, while the sonographic diagnosis was in concordance with the final diagnosis in 75 (96%) of the patients. Chest sonography therefore significantly increased the rate of correct diagnoses from 77% (95% confidence interval, 67-87%) to 96% (95% confidence interval, 92-100%; p < 0.0001). Sonography provided new information in 52 patients (67%): a different diagnosis from the initial diagnosis in 18 patients and additional diagnostic information in 34 patients. New information gained from sonography affected the management of 35 patients. Sonography also provided help in guiding 42 (70%) of 60 invasive diagnostic procedures and 22 (73%) of 30 invasive therapeutic procedures for which chest radiography and physical examination had failed to or were unsuitable to provide guidance. Overall, sonography assisted in the management of 64 (82%) of 78 patients. Sonography was of no benefit in 14 patients (18%). CONCLUSIONS: We conclude that chest sonography can complement chest radiography and is of value in the diagnosis and management of emergency department patients with acute chest diseases presenting as opacities on chest radiographs.

Acute Disease↗

PubMed2001

Paget disease of the breast--an easily overlooked disease?

BACKGROUND AND OBJECTIVES: Paget disease of the breast has long been recognized as a distinct clinical disease. The clinical manifestations and outcomes of Paget disease of the breast were reviewed to understand its earlier diagnostic clues and achieve an optimal treatment plan. Patients and Methods Thirty-one patients with Paget disease of the breast were included in this study. The postoperative outcomes and possible related prognostic factors were reviewed and analyzed. RESULTS: The 5-year overall survival was 69%. Nineteen patients (61%, Group A) did not have a palpable breast mass and 12 patients (39%, Group B) had a palpable breast mass. There was significant difference (P < 0.01) in the 5-year overall survival between Group A (94%) and Group B (19%). Group A patients had significantly higher incidences of underlying noninvasive breast carcinoma (73% vs. 8%, P < 0.01) and n0 lymph nodes status (84%vs. 50%, P = 0.043) than those of Group B. CONCLUSIONS: Paget disease of the breast without a palpable breast mass carries a more favorable prognosis. Patients with any nipple complaints deserve a detailed evaluation even in the absence of a palpable breast mass in order not to overlook a favorable disease.

Adult↗

PubMed2001

Changes in bacterial concentration in the liver correlate with that in the hepaticojejunostomy after bile duct reconstruction: implication in the pathogenesis of postoperative cholangitis.

Postoperative cholangitis is a frequent and unpredictable complication of unknown etiology following bile duct reconstruction (BDR), particularly for biliary atresia. This study was undertaken to correlate the growth of bacteria in the hepaticojejunostomy with that in the liver after BDR. Quantitative bacterial culture was done on the specimens taken from the liver and from the hepaticojejunostomy at 1 week (group 1, n = 7), 1 month (group 2, n = 7), and 2 months (group 3, n = 7) following BDR with Roux-en-Y hepaticojejunostomy in piglets after 2 weeks of common bile duct ligation. The histological examination of the liver and the hepaticojejunostomy, as well as serial monitoring of hemogram and liver function tests, were performed to correlate the findings with the bacterial concentration of the liver and the hepaticojejunostomy following BDR. The bacterial concentration of the hepaticojejunostomy, expressed as log10 colony-forming units per gram (log10 CFU/g) of the hepaticojejunostomy, showed a progressive decrease from 8.38 +/- 1.36 in group 1, 7.07 +/- 2.54 in group 2, to 3.56 +/- 1.31 in group 3 (p = 0.001). The log10 CFU/g of the liver also showed a progressive decrease from 5.02 +/- 1.59 in group 1, 3.16 +/- 1.56 in group 2, to 2.19 +/- 1.09 in group 3 (p = 0.006). There was a significant positive correlation of the log10 CFU/g of the liver (n = 21) with that of the hepaticojejunostomy (n = 21) following BDR (r = 0.600, p = 0.004). Most of the infectious pathogens isolated from the liver were also isolated from the hepaticojejunostomy. The changes in hemoglobin, bilirubin, albumin, and ammonia significantly correlated with the changes of the bacterial concentration of the liver. The results of the study suggests that hepatic bacterial proliferation after BDR is significantly affected by microbial overgrowth in the bilioenteric anastomosis and is associated with deteriorated liver function and hemogram.

Anastomosis, Surgical↗

PubMed2001

Patellar tension band wiring: a revised technique.

Using a modified AO tension band wiring technique to treat a patellar fracture has become popular and has achieved a high success rate. However, the technique of Kirschner wire insertion has not been considered in detail, which may migrate and consequently introduce fragments loss of reduction. A revised technique involving bending both ends of the Kirschner wires was prospectively studied. Sixty-eight consecutive patients were so treated, and 62 patients were followed-up for at least 2 years (range 2-6 years). All fractures healed with a union rate of 100% (62/62) and a union period of 2.5 +/- 0.5 months. Skin irritation was noted in 2 patients (3%). All patients achieved a satisfactory result. We therefore recommend this revised technique to treat all patellar fractures because of its high union rate and low complication rate.

Adolescent↗

PubMed2001

Isolated Rosai-Dorfman disease presenting as peripheral mononeuropathy and clinically mimicking a neurogenic tumor: case report.

BACKGROUND: Rosai-Dorfman disease is a rare idiopathic disorder of proliferative histiocytes affecting the lymph nodes. It usually manifests as bilateral cervical lymphadenopathy and fever with concurrent polyhyperglobulinemia. Cases involving the nervous system are quite rare; most CNS lesions are located intracranially or arise from the spinal dura or leptomeninges. To our knowledge, there has been no previous report of isolated Rosai-Dorfman disease presenting as peripheral mononeuropathy. CASE REPORT: We report a 43-year-old female with isolated extranodal Rosai-Dorfman disease in the medial aspect of the right upper arm, which presented as aberrant ulnar neuropathy caused by a mass encasing the right basilic vein and the medial anteriobrachial cutaneous branch of the right ulnar nerve. Preoperative diagnosis was a neurogenic tumor. The patient underwent excision of the mass, and pathologic examination confirmed the diagnosis of Rosai-Dorfman disease. CONCLUSION: An unusual case of extranodal isolated Rosai-Dorfman disease, presenting as peripheral mononeuropathy, is reported. Clinically, it simulated a neurogenic tumor, extending the etiologic spectrum of entrapment neuropathy of the peripheral nerve.

Adult↗

PubMed2001

Progesterone receptor in patients with hepatolithiasis.

Altered gallbladder motility by progesterone has been recognized as an important factor in the development of gallstones. There are two types of hepatolithiasis, that occurs de novo in the intrahepatic ducts with an intact gallbladder (primary hepatolithiasis) and that which originates in the gallbladder and the stones migrate into the intrahepatic duct (secondary hepatolithiasis). This study was designed to evaluate the possible role of the progesterone receptor of gallbladder in the pathogenesis of hepatolithiasis. Eighty-four patients with hepatolithiasis (34 patients had primary hepatolithiasis and the other 50 patients secondary hepatolithiasis) were included. Paraffin-embedded specimens of gallbladder were processed to have an immunohistochemical staining for progesterone receptor. Positivity for progesterone receptor of gallbladder specimens was noted in eight patients (23.5%) with primary hepatolithiasis and in 23 patients (46%) with secondary hepatolithiasis. There is significant difference (P = 0.031) in positive rate for progesterone receptor between the primary hepatolithiasis and secondary hepatolithiasis groups. In conclusion, many more patients (46%) with secondary hepatolithiasis show positivity for progesterone receptor of gallbladder specimens than patients with primary hepatolithiasis (23.5%) (P = 0.031). This phenomenon is intriguing and should be of further evaluation and elucidated.

Bile Ducts, Intrahepatic↗

PubMed2001

Bradycardia and permanent pacing after bilateral thoracoscopic T2-sympathectomy for primary hyperhidrosis.

A 23-year-old woman with craniofacial hyperhidrosis underwent bilateral thoracoscopic T2-sympathectomy. Marked sinus bradycardia with a mean heart rate of 49 beats/min by Holter ECG monitoring occurred after the procedure and persisted for > 2 years. Normal sinus node function was found by an invasive electrophysiological study and unopposed vagotonia after sympathectomy was diagnosed. A permanent pacemaker was implanted. Although reduced heart rate is a common phenomenon after bilateral dorsal sympathectomy, intractable bradycardia with permanent pacing is rare. This patient demonstrates one of the potential cardiac complications of bilateral sympathectomy.

Adult↗

PubMed2001

An epidemiological study of nocturnal enuresis in Taiwanese children.

OBJECTIVE: To estimate the prevalence of primary nocturnal enuresis (PNE) in Taiwanese children, and to examine factors associated with PNE and its severity. SUBJECTS AND METHODS: In all, 1683 questionnaires were sent to parents of schoolchildren aged 6-11 years randomly selected from three primary schools in Taipei City, Taiwan. The questionnaire was designed to collect information about the prevalence of and factors associated with PNE. RESULTS: Of the questionnaires distributed, 1176 (70%) were completed. PNE was reported in 92 (8%) of the children; nine (10%) of these children were wet > 3 nights per week. Factors associated with PNE included male gender, deep sleep, divorced parents or separated family and a positive family history of enuresis. Of these factors, only those children with deep sleep were more likely to have > 3 wet nights per week. CONCLUSION: The prevalence of and factors associated with PNE in Taiwan are similar to those reported in Western countries, but the percentage of children with severe enuresis is lower than in Sweden, France and Turkey. Deep sleepers are more likely to have severe enuresis.

Analysis of Variance↗

PubMed2001

Increased levels of tissue plasminogen activator antigen and factor VIII activity in nonvalvular atrial fibrillation: relation to predictors of thromboembolism.

INTRODUCTION: Given that nonvalvular atrial fibrillation (AF)-associated stroke can be either cardioembolic or atherothrombotic, we investigated the relationships between nonvalvular AF and hemostatic factors reflecting intrinsic thrombogenic and atherogenic potentials (tissue plasminogen activator [t-PA] antigen, plasminogen activator inhibitor-1, and factor VIII activity). We also evaluated the clinical applicability of these hemostatic factors by examining whether AF subjects with established clinical or echocardiographic predictors of thromboembolism had higher levels of these factors. METHODS AND RESULTS: Of the 3,212 participants of a Chinese population-based study, 53 subjects (1.7%) with AF were identified. Among the hemostatic factors measured, t-PA antigen (median 12.8 vs 8.1 ng/mL; P < 0.01) and factor VIII activity (median 155% vs 133%; P < 0.05) were significantly higher in AF subjects after adjustment for age and sex. In multivariate analysis, features independently associated with t-PA antigen levels were AF, sex, body mass index, systolic blood pressure, total cholesterol, triglycerides, and left ventricular systolic dysfunction. Features independently associated with factor VIII activity levels included AF, age, and total cholesterol. Levels of both t-PA antigen and factor VIII activity were primarily elevated in AF subjects with predictors of thromboembolism (age > 75 years, hypertension, diabetes, and left ventricular systolic dysfunction), whereas in AF subjects with no thromboembolic predictors, plasma levels of hemostatic factors examined were similar to those without AF. CONCLUSION: We demonstrated that nonvalvular AF was independently associated with increased peripheral levels of t-PA antigen and factor VIII activity. Levels of both hemostatic factors were primarily elevated in AF subjects with predictors of thromboembolism. Whether these hemostatic factors are independently predictive of future thromboembolic events in AF patients requires further investigation.

Adult↗

PubMed2001