Chelation-Tamoxifen Conjugates for Imaging of Estrogen Receptors.

Background: The differential diagnosis of estrogen receptor-positive (ER+) pathway-activated systems by using a labeled antiestrogen helps to select the patients for optimal response to endocrine therapy and to discontinue the treatment when resistance occurs. The authors' purpose was to synthesize chelator-tamoxifen conjugates for imaging ER (+) diseases. Materials and Methods: A hydroxypropyl linker was incorporated between either cyclam or cyclam diacetic acid and tamoxifen analog to produce SC-05-L-1 (Z-1-(1,4,8,11-tetraazacyclotetradecan-1-yl)-3-((5-(4-(2-(diethylamino)ethoxy)phenyl)-4,5-diphenylpent-4-en-1-yl)oxy)propan-2-ol) and SC-05-N-1 (Z-2,2'-(4-(3-((5-(4-(2-(diethylamino)ethoxy)phenyl)-4,5-diphenylpent-4-en-1-yl)oxy)-2-hydroxy-propyl)-1,4,8,11-tetraazacyclotetradecane-1,8-diyl)diacetic acid), respectively. In vitro cell uptake and cell/media ratios of 99mTc-SC-05-L-1 and 99mTc- SC-05-N-1 in ER (+) ovarian cancer cells (TOV-112D and OVCAR3) were performed. To ascertain the specificity of cell uptake, the cell uptake was blocked with estrone. In vivo 99mTc-SC-05-L-1 or 99mTc-SC-05-N-1 single-photon emission computed tomography/computed tomography was conducted in tumor-bearing rodents and compared to 18F-fluoro-2-deoxy-d-glucose (18F-FDG) positron emission tomography/magnetic resonance imaging (a reference technology). Results: The radiochemical purities of 99mTc-SC-05-L-1 and 99mTc-SC-05-N-1 were greater than 99% (n = 10). 99mTc-SC-05-L-1 had higher cell/media ratios than 99mTc-SC-05-N-1 in OVCAR-3 ER (+) cells. The cell uptake of 99mTc-SC-05-L-1 was blocked 80% by estrone indicating an ER-mediated process occurred. 99mTc-SC-05-N-1 was further selected for in vivo imaging studies due to higher maximum tolerated dose and superior water solubility than 99mTc-SC-05-L-1. 99mTc-SC-05-N-1 showed higher tumor uptake and tumor/muscle count density ratios than 18F-FDG in tumor-bearing rodents. Conclusion: 99mTc-SC-05-N-1 showed better differential diagnosis of ovarian tumors than 18F-FDG, indicating great promising in chelator-tamoxifen conjugate for ER pathway-directed systems imaging.

Factors affecting Taiwanese women's choice of Cesarean section.

The rising rate of cesarean section (CS) is a subject of concern, intensive discussion, and investigation. However, few, if any, systematic studies of this trend have been recorded among the oriental populations. This study examines factors that may contribute to the high incidence of CS in Taiwan, where the rate of CS is among the highest in the world. Multiple logistic regression and stratified analyses were used to determine the association between CS and various factors, including provider and patient parameters. Our study sample of 2,497 cases was drawn from a total of 10,654 in-patient deliveries in Chang Gung Memorial Hospital of Taiwan. A number of factors associated with the use of CS were explored, including maternal age, occupation, education and marital status of the mother, sex and body weight of the infant at birth, parity, insurance status, source of admission, and time of birth. Our study also shows that CS in Taiwan is affected by the folk belief of Pe-Ji, which influences the preference of some patients for delivery at a specific time. Such a preference reflects a unique right of choice by women in Taiwan.

Mining three-dimensional anthropometric body surface scanning data for hypertension detection.

Hypertension is a major disease, being one of the top ten causes of death in Taiwan. The exploration of three-dimensional (3-D) anthropometry scanning data along with other existing subject medical profiles using data mining techniques becomes an important research issue for medical decision support. This research attempts to construct a prediction model for hypertension using anthropometric body surface scanning data. This research adopts classification trees to reveal the relationship between a subject's 3-D scanning data and hypertension disease using the hybrid of the association rule algorithm (ARA) and genetic algorithms (GAs) approach. The ARA is adopted to obtain useful clues based on which the GA is able to proceed its searching tasks in a more efficient way. The proposed approach was experimented and compared with a regular genetic algorithm in predicting a subject's hypertension disease. Better computational efficiency and more accurate prediction results from the proposed approach are demonstrated.

Waist-to-thigh ratio can also be a better indicator associated with type 2 diabetes than traditional anthropometrical measurements in Taiwan population.

PURPOSE: Using three-dimensional (3D) scanning data along with other existing subject's medical profiles to search for better anthropometric markers in association with type 2 Diabetes Mellitus (DM). METHODS: In this cross-sectional study with 6007 subjects undergoing health examination in a period of 3 years, the authors adopted data from 3D scanning with hundreds of body measures and conducted factor analysis to search for practical indicators better associated with type 2 DM. A multiple logistic regression model was used to analyze strength of association between indicators and presence of type 2 DM. RESULTS: The trunk component derived from factor analysis was positively associated with type 2 DM, regardless of obesity status. However, lower limbs component was found to be negatively associated with type 2 DM in the same stratifications. Waist was thus found as the strongest indicator among practical measures of trunk component. The strength of association between thigh and type 2 DM was found to be the highest among practical measures of lower limbs component. A marker from taking the ratio of waist to thigh (WTR) was derived from the approach which was found to be the best indicator for association with type 2 DM while comparing to body-mass index, waist circumference, or waist-hip ratio. CONCLUSION: This study offers a low-cost, noninvasive practical marker that is better associated with the presence of type 2 DM. WTR, with further study, may be used in clinical practice, epidemiological study, and preventive medicine in the future.

Case payment and the adoption of new technology: an empirical study of cataract surgery in Taiwan.

BACKGROUND: Case payment for cataract surgery with Government Employee Insurance (GEI) was implemented at Chang Gung Memorial Hospital (CGMH) in March 1994, and fee-for-service (FFS) was retained for cataract inpatients with or without other health insurance. We examined the impact of this change in the reimbursement policy from FFS to case payment on the health care provider's practice behavior towards a new emerging technology, using cataract surgery as an example. METHODS: Secondary data analysis was performed using 1 year of CGMH data before (period 1, from March 1993 to February 1994) and after (period 2, from March 1994 to February 1995) implementing the new policy. Inpatient records for cataract surgery using either extracapsular cataract extraction (ECCE, the old technology) or phacoemulsification (Phaco, the new technology) were included. Logistic regression models were employed to assess how case payment affected the health care provider's adoption of new technology. RESULTS: The percentage of cases treated using the new Phaco technology grew from period 1 (6.6%) to period 2 (23.6%) among all 4 study groups, despite Phaco being more expensive than ECCE. More importantly, the increment ratio of Phaco use from periods 1 to 2 was the smallest for GEI patients (3.26-fold) when compared with the other 3 groups (4.16-5.29-fold). CONCLUSIONS: Both new technology and cost containment strategies should be taken into account when setting up a reimbursement policy.