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H S Chen

Publications and source records attributed to H S Chen.

At least 19 recordsLinked to original sources
PubMed2003

Observation of a near-threshold enhancement in the pp mass spectrum from radiative J/psi-->gammapp decays.

We observe a narrow enhancement near 2m(p) in the invariant mass spectrum of pp pairs from radiative J/psi-->gammapp decays. No similar structure is seen in J/psi-->pi(0)pp decays. The results are based on an analysis of a 58 x 10(6) event sample of J/psi decays accumulated with the BESII detector at the Beijing electron-positron collider. The enhancement can be fit with either an S- or P-wave Breit-Wigner resonance function. In the case of the S-wave fit, the peak mass is below 2m(p) at M=1859(+3)(-10) (stat)+5-25(syst) MeV/c(2) and the total width is Gamma<30 MeV/c(2) at the 90% confidence level. These mass and width values are not consistent with the properties of any known particle.

Journal Article↗
PubMed2003

Successful treatment with weekly paclitaxel in a patient with recurrent endometrial cancer. A case report.

The best treatment for recurrent endometrial cancer is still uncertain, although weekly paclitaxel has shown some promise in the management of this disease. In this report we present a patient with recurrent endometrial cancer treated with weekly paclitaxel. Serial power Doppler angiography was used to assess the effects of therapy. The response was good, suggesting that recurrent endometrial cancer may be successfully treated with weekly paclitaxel and effectively monitored with power Doppler angiography.

Adenocarcinoma↗
PubMed2001

Serum levels of matrix metalloproteinase 2 in patients with breast cancer.

Matrix metalloproteinases (MMPs) have been reported to be associated with invasive and metastatic behaviors of human malignant tumors. However, there is still limited knowledge about the role of matrix metalloproteinases-2 (MMP-2) in breast cancer. This study was designed with the aim to elucidate the possible relationship between the preoperative circulating MMP-2 and breast cancer. Fifty-seven consecutive patients with invasive breast cancer undergoing surgery were prospectively included and evaluated. Venous blood samples were collected before the surgery. Sera were obtained by centrifugation, and stored at -70 degrees C until assayed. The control group consisted of 12 patients with benign breast tumor (six with fibrocystic disease and six with fibroadenoma). Serum concentrations of MMP-2 were measured by the quantitative sandwich enzyme immunoassay technique. The data on primary tumor stage, age, estrogen receptor, lymph node status, and TNM staging were reviewed and recorded. The mean value of serum MMP-2 in patients with invasive breast cancer was 694.3+/-140.5 ng/ml and those of control group were 593.3+/-134.0 ng/ml and the difference was significant (P=0.026). Furthermore, there were significantly higher serum levels of MMP-2 in the patients with more advanced primary tumor staging (P=0.005), in the patients with more advanced lymph node status(P=0.011) and in the patients with more advanced TNM staging (P<0.001). In multivariate analysis, TNM staging (P<0.001) appeared as independent factor regarding the significant higher serum levels of MMP-2. Patients with more advanced TNM staging were shown to have higher serum MMP-2 levels. Thus preoperative serum MMP-2 levels might reflect the severity of invasive breast cancer and deserve further evaluation.

Adult↗
PubMed2001

Tellurium-bridged manganese carbonyl clusters: synthesis and structural transformations of [Te4Mn3(CO10]-, [Te2Mn3(CO)9]2-, [Te2Mn3(CO)9]-, and [Te2Mn4(CO)12]2-.

The reactions of appropriate ratios of K2TeO3 and [Mn2(CO)10)] in superheated methanol solutions lead to a series of novel cluster anions [Te4Mn3(CO)10] (1), [Te2Mn3(CO)9]2- (2), [Te2Mn3(CO)9]- (3), and [Te2Mn4(CO)12]2- (4). When cluster 1 is treated with [Mn2(CO)10]/KOH in methanol, paramagnetic cluster 2 is formed in moderate yield. Cluster 2 is oxidized by [Cu(MeCN)4]BF4 to give the closo-cluster [Te2Mn3(CO)9]- (3), while treatment of 2 with [Mn2(CO)10]/KOH affords the closo-cluster 4. IR spectroscopy showed that cluster 1 reacted with [Mn2(CO)10] to give cluster 4 via cluster 2. Clusters 1-4 were structurally characterized by spectroscopic methods or/and X-ray analyses. The core structure of 1 can be described as two [Mn(CO)3] groups doubly bridged by two Te2 fragments in a mu2-eta2 fashion. Both [Mn(CO)3] groups are further coordinated to one [Mn(CO)4] moiety. Cluster 2 is a 49 e- species with a square-pyramidal core geometry. While cluster 3 displays a trigonal-bipyramidal metal core, cluster 4 possesses an octahedral core geometry.

Journal Article↗
PubMed2001

Establishment of bee venom-induced contralateral heat hyperalgesia in the rat is dependent upon central temporal summation of afferent input from the site of injury.

The present investigation was designed to study whether central sensitization is determined by a time window of central summation of ongoing primary afferent input from a peripheral injury site. Sensitization was assessed behaviorally in the rat as contralateral heat hyperalgesia induced by injection of bee venom (BV) in the hind paw. The sciatic nerve was transected at various time points following intraplantar BV injection to analyze the time window for contralateral hyperalgesia. The results show that after a dose of 0.2 mg BV, axotomy at 5 min completely prevented contralateral heat hyperalgesia but was without effect at 10 min, whereas after a dose of 0.1 mg BV, axotomy at 10 min was able to prevent the contralateral heat hyperalgesia but remained without effect at 20 min. These findings suggest an important role of the amount of ipsilateral ongoing primary afferent in establishing the contralateral heat hyperalgesia. Moreover, by counting the total amount of paw flinches that is believed to be mediated by ongoing primary afferent input, it was shown that 87.35+/-5.36, 170.50+/-9.15 and 305.80+/-20.13 flinches were induced by 0.2 mg BV for a period of 5, 10 and 20 min, respectively. At the lower dose of 0.1 mg BV significant fewer flinches were elicited with 59.17+/-13.54, 133.00+/-22.33 and 234.00+/-36.42 within the three corresponding time windows before sciatic nerve transection. The results suggest that the amount of primary afferent input determines the time window required to establish central changes that are independent of further afferent input.

Afferent Pathways↗
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

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

Total pelvic exenteration for primary local advanced colorectal cancer.

Total pelvic exenteration (TPE) is an ultraradical operative procedure for locally advanced pelvic tumors with high morbidity and mortality rates. We retrospectively reviewed the results of TPE for primary locally advanced colorectal cancer in terms of mortality, morbidity, and long-term survival. Of 2952 patients with colorectal cancer, 50 underwent TPE for primary locally advanced colorectal cancer between 1986 and 1995. There was one operative death (2%). The other 49 cases were entered into a retrospective study. Thirty-two cases (65%) showed involvement of one or more adjacent organs. Thirty-one patients (97%) had urologic organs invaded by tumor. The overall 5-year survival rate was 49% and the overall morbidity was 37%. The survival rate for stage II was 62%, and that for stage III was 35%; there was no survival in stage IV. Early morbidity was noted in 24% of patients; late morbidity, in 15%. TNM stage appeared to be the only independent factor for survival (p = 0.022). Our study showed that TPE can be performed with relatively low operative mortality and acceptable morbidity. With thorough preoperative evaluation and adequate surgical dissection, satisfactory outcomes for a primary locally advanced colorectal cancer can be achieved, especially at the earlier stages.

Adenocarcinoma↗
PubMed2001

Review of telemedicine projects in Taiwan.

Taiwan is a heavily populated country, with a small land area and many mountains and isolated islands. Because medical resources are unequally distributed, high quality accessible medical care is a major problem in rural areas. Medical personnel are unwilling to practice in rural areas because of fear of isolation from peers and lack of continuing medical education (CME) in those areas. Telemedicine provides a timeless and spaceless measure for teleconsultation and education. The development of telemedicine in Taiwan began under the National Information Infrastructure (NII) Project. Distance education and teleconsultation were the first experimental projects during the initiation research stage. The cost and effectiveness of the hardware and network bandwidth were evaluated. In the promotion research stage, applications in different medical disciplines were tested to promote multipoint videoconference, electronic journals and VOD. Investigation of user satisfaction put on more emphasis on improving application functions. In 1998, a new Cyber Medical Center (CMC) international collaboration project was begun, integrating technologies of multimedia, networking, database management, and the World Wide Web. The aim of the CMC is to create a multimedia network system for the management of electronic patient records, teleconsultation, online continuing medical education, and information services on the web. A Taiwan mirror site of Virtual Hospital and two international telemedicine trials through Next Generation Internet (NGI) were done at the end of 1998. In the future, telemedicine systems in Taiwan are expected to combine the Internet and broadband CATV, ADSL, and DBS networking to connect clinics, hospitals, insurance organizations, and public health administrations; and, finally, to extend to every household.

Databases, Factual↗
PubMed2001

Implementation and evaluation of a multifunctional telemedicine system in NTUH.

In this article, we proposed a multifunctional telemedicine system supporting both telediagnosis and teleconsultation services. We attempted not only to insure that the implementation of this system satisfied most requirements, but also to evaluate the impact of the system. With regard to system architecture, we designed a unified multimedia database to store all types of data and used two kinds of network (ATM and ISDN) for different possible applications. As for data transmission, the REFRESH and PREFETCH mechanisms were implemented to enhance data transfer efficiency. A total of 1107 consultations employing the telemedicine system were performed during the past 3 years. This technology was used most frequently for radiology consultation (32.7%, n = 362) and ultrasonic examination (19.5%, n = 216). An evaluation of the impact on diagnosis (507 valid cases) indicated that the diagnosis in 80 cases (15.78%) were altered on the basis of second opinions from a medical center; and the number of patients transferred to the medical center was reduced from 24 (4.7%) to eight cases. Most of the rural-site physicians (97%) thought that they did benefit from specialists' experience and knowledge via the telemedicine system. Based on 431 valid questionnaires, the number of the patients with confidence in the telemedicine system at their local healthcare center increased from 72.6% to 87.5%. Overall, more than 90% of patients and physicians believed that the system was valuable and provided satisfactory services.

Adolescent↗
PubMed2001

Abnormal cardiovascular reflex tests are predictors of mortality in Type 2 diabetes mellitus.

AIMS: To determine whether diabetic autonomic neuropathy is an important factor contributing to mortality in Type 2 diabetes mellitus. METHODS: Between 1989 and 1993, 431 men and 181 women with Type 2 diabetes were given diabetic autonomic neuropathy cardiovascular reflex (CVR) tests. These subjects were followed for the subsequent 5--9 years to assess mortality rates. RESULTS: The prevalence rate of abnormal CVR tests was 46.1% in patients with the history of diabetes less than 5 years and up to 69.4% when the history of diabetes exceeded 20 years. During the follow-up period from 1 January 1989 to 31 December 1997 (mean 7.7 years), a total of 135 participants died. The 8-year survival rate for patients with abnormal CVR tests was 63.6% in males and 76.4% in females, compared with 80.9 and 93.3% for patients with normal CVR tests. The results were grouped as: group 1, normal CVR tests without postural hypotension (PHT); group 2, normal CVR tests with PHT; group 3, abnormal CVR tests without PHT; and group 4, abnormal CVR tests with PHT. The 8-year survival rate was 85.4% in group 1, 80.9% in group 2, 74.5% in group 3 and 61.1% in group 4. CONCLUSION: Type 2 diabetic patients with abnormal CVR tests may have increased mortality, and those combined with postural hypotension have higher mortality than those without. Abnormal CVR tests may be important predictors of mortality in Type 2 diabetes mellitus.

Blood Pressure↗
PubMed2001

Microsatellite alterations in exfoliated cervical epithelia deoxyribonucleic acid as a marker for high-grade dysplasia.

OBJECTIVE: The purpose of this study was to evaluate the feasibility of the use of deoxyribonucleic acid microsatellite alterations in cervical epithelia in the prediction of high-grade dysplasia and to compare it with a strategy based on human papillomavirus testing. STUDY DESIGN: Our prospective study subjects were from a cohort of 498 women with minimally abnormal Papanicolaou test results including atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesion who had documented repeated Papanicolaou and human papillomavirus tests. Of these, 52 eligible patients having conizations or hysterectomies as their histologic outcomes were subjected to tests of loss of heterozygosity on a panel of 5 microsatellites (D3S1110, THRB, D3S1228, D6S291, D3S1289) within the deoxyribonucleic acid of exfoliated cervical epithelia. These genetic alterations were analyzed through fluorescence polymerase chain reaction by comparison of allele ratios of exfoliated cells with those of normal control tissue. Predictive values for high-grade cervical dysplasia and cancer between this deoxyribonucleic acid marker and human papillomavirus status were compared. RESULTS: With the use of loss of heterozygosity in at least one locus for predicting high-grade cervical neoplastic lesion, the sensitivity, specificity, positive predictive value, and negative predictive value were 96.7%, 59.1%, 76.3%, and 92.9%, which were superior to those of the human papillomavirus test (80%, 59.1%, 72.7%, and 92.9%). As a triage for atypical squamous cells of undetermined significance, its sensitivity and negative predictive value were up to 100%. CONCLUSION: The promising results on determining microsatellite alteration in dysplastic lesions might imply that it is possible to detect the earliest changes by potential molecular markers with exfoliated cervical epithelial cells.

Adolescent↗
PubMed2001

Treatment of painful heel syndrome with shock waves.

In a prospective clinical study, the effectiveness of shock waves on painful heel syndrome in 80 patients (20 men and 60 women) with an average age of 48 years was investigated. Six patients had bilateral treatments. Each treatment consisted of 1,000 impulses of shock waves at 14 kV. A 100-point scoring system (70 points for pain and 30 points for function) was used for evaluation. The intensity of pain was measured with a visual analog scale from 0 to 10. The overall results were no complaints in 20.6%, significantly better in 52.9%, slightly better in 17.6%, and unchanged in 8.8% of 64 patients (68 heels) with 12 weeks followup; no complaints in 59.3%, significantly better in 27.7 %, slightly better in 13% of 52 patients (54 heels) with 6 months followup. None of patients' symptoms became worse. Seventeen patients (18 heels) who did not respond favorably to the first treatment had significantly better results after a second treatment. There were no device-related problems, and no systemic or local complications. Shock wave treatment is a new modality of therapy that is safe and effective in the treatment of patients with painful hell syndrome.

Adult↗
PubMed2001

Treatment of lateral epicondylitis of the elbow with shock waves.

In a prospective clinical study, the effectiveness of shock wave treatment for lateral epicondylitis in 56 elbows in 53 patients (27 men and 26 women) with an average age of 46 years was investigated. Three patients received treatment for both elbows. Each elbow was treated with 1,000 impulses of shock waves at 14 kV. A 100-point scoring system was used for evaluation including 40 points for pain, 30 points for function, 20 points for strength, and 10 points for elbow motion. The intensity of pain was measured using a visual analogue scale from 0 to 10. The overall results were 13.2% excellent, 44.7% good, 36.8% acceptable, and 5.3 unchanged in 35 patients with 12 weeks followup; 30.8% excellent, 42.3% good, and 26.9% acceptable in 25 patients with 24 weeks followup. Considerable improvement was observed from 6 weeks to 6 months after the treatment. None of the patients' symptoms became worse. The results of nine patients who also received a second treatment were good in three patients, acceptable in five patients, and unchanged in one patient. There was no device-related problems, systemic, or local complications. Shock wave therapy may offer a new and safer nonoperative treatment for patients with lateral epidoncylitis of the elbow.

Adult↗
PubMed2001

Treatment of calcifying tendinitis of the shoulder with shock wave therapy.

In a prospective clinical study, the effectiveness of shock wave treatment for calcifying tendinitis in 31 shoulders in 29 patients (14 women and 15 men) with an average age of 52 years was assessed. Each shoulder was treated with 1,000 impulses of shock waves at 14 kV. A 100-point Constant score system was used for evaluation. The overall results of 20 patients (21 shoulders) with 12 weeks followup were no complaints in 23.8%, significantly improved in 38.1%, some improvement in 14.3%, and unchanged in 23.8%. Considerable improvement was observed between 6 and 12 weeks. The results of seven patients with 24 weeks followup were no complaints in two patients, significantly improved in three, and unchanged in two patients. Radiographs showed complete elimination of the calcium deposits in six patients (28.6%), incomplete elimination in two patients (9.5%), and three patients (14.3%) had fragmentation of the calcium deposits. There was no recurrence of calcium deposits observed at 24 weeks. There was a correlation between the functional improvement and the elimination of calcium deposits. There were no device-related problems, systemic or local complications. Low-energy shock wave therapy may offer a new and safer additional nonoperative treatment for patients with calcifying tendinitis of the shoulder.

Adult↗
PubMed2001

Treatment of nonunions of long bone fractures with shock waves.

A prospective clinical study investigated the effectiveness of shock waves in the treatment of 72 patients with 72 nonunions of long bone fractures (41 femurs, 19 tibias, seven humeri, one radius, three ulnas and one metatarsal). The doses of shock waves were 6,000 impulses at 28 kV for the femur and tibia, 3,000 impulses at 28 kV for the humerus, 2,000 impulses at 24 kV for the radius and ulna, and 1,000 impulses at 20 kV for the metatarsal. The results of treatment were assessed clinically, and fracture healing was assessed with plain radiographs and tomography. The rate of bony union was 40% at 3 months, 60.9% at 6 months, and 80% at 12 months followup. Shock wave treatment was most successful in hypertrophic nonunions and nonunions with a defect and was least effective in atrophic nonunions. There were no systemic complications or device-related problems. Local complications included petechiae and hematoma formation that resolved spontaneously. In the authors' experience, the results of shock wave treatment were similar to the results of surgical treatment for chronic nonunions with no surgical risks. Shock wave treatment is a safe and effective alternative method in the treatment of chronic nonunions of long bones.

Adolescent↗
PubMed2001

Intraocular lens implantation after penetrating keratoplasty.

PURPOSE: We evaluated the clinical results of nonsimultaneous penetrating keratoplasty, cataract extraction, and intraocular lens (IOL) implantation (two-stage surgery) for combined corneal disease and cataract. METHODS: Twenty-six eyes of 24 patients with an average age of 46 years who underwent two-stage surgery were studied retrospectively. Variables included visual acuity, refractive status, specular microscopy before and after IOL implantation (6 months), and the occurrence of graft failure. Astigmatism was corrected by suture removal and relaxing incision. The mean follow-up after IOL placement was 16 months. RESULTS: Unaided visual acuity was 20/100 or better in 22 (83%) eyes after the second procedure. Twenty-one (81%) eyes had an aided visual acuity of at least 20/40. The mean refractive and absolute errors were -1.49 +/- 1.39 diopters (D) and 1.55 +/- 1.30 D, respectively. The mean keratometric and refractive cylinders were 3.50 D and 2.26 D, respectively. Nineteen (73%) eyes had a spherical equivalent refraction within 2 D of emmetropia. Anisometropia (> or =3 D) occurred in four (15%) eyes. The endothelial cell density, the coefficient of variation, and the percentage of hexagonal cells documented by specular microscopy were not significantly different before and after IOL implantation. Complications included three rejections, two cases of herpetic recurrence, and one late decompensation. Two graft failures (8%) occurred after secondary surgery. CONCLUSION: The two-stage surgery is a safe and effective modality.

Adolescent↗