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Biomedical subjects

F M Chang

Publications and source records attributed to F M Chang.

At least 37 records · Page 2Linked to original sources
PubMed1997

The dopamine D4 receptor gene (DRD4) is not associated with alcoholism in three Taiwanese populations: six polymorphisms tested separately and as haplotypes.

The dopaminergic system has been implicated in alcoholism but studies at the dopamine D2 receptor gene (DRD2), one of the five dopamine receptors, have not given a consistent picture of an association with alcoholism. We have now studied the dopamine D4 receptor gene (DRD4) using six polymorphisms, both separately and as haplotypes. Three groups of alcoholics from Taiwan (Atayal, Ami, and Han) diagnosed as having severe alcohol dependence using DSM-III-R criteria, together with nonalcoholics matched for gender, ethnic group, and geographic origin, were typed by polymerase chain reaction (PCR) and/or PCR-restriction fragment length polymorphism (RFLP) for all six polymorphisms. Three out of six markers are polymorphic in all three Taiwanese populations. Although the prevalence rates of alcoholism are remarkably different, no highly significant association of this locus with alcoholism was observed in any of the three groups whether the analysis considered genotype distributions or allele frequencies at the three polymorphic markers considered individually and as haplotypes. Neither is there any obvious pattern in the data that covaries with or hints at a relationship with the very different prevalences of alcoholism in the groups studied. Especially because the powerful, multi-site haplotype analysis was not statistically significant in any of the population samples, we conclude that there is no association of the DRD4 locus with alcoholism in Taiwanese populations.

Alcoholism↗
PubMed1997

Prenatal sonographic diagnosis of single umbilical artery.

PURPOSE: We evaluated the reliability of prenatal sonography and the usefulness of the umbilical vein and artery diameter ratio, transverse umbilical artery diameter, and systolic-diastolic ratio in detecting single umbilical artery (SUA). METHODS: In 24 of 6,970 fetuses, SUA was detected using prenatal sonography and confirmed at birth. These cases were retrospectively reviewed. RESULTS: Four fetuses had major malformations, and 1 had a minor anomaly. Thirteen fetuses with SUA underwent chromosomal analysis, and only 2 had abnormal karyotypes. Most of the SUA fetuses had a normal systolic-diastolic ratio. CONCLUSIONS: Our retrospective study determined that the prognosis of SUA fetuses is good when there is no concurrent anatomic or chromosomal abnormality. Although some reports claim that the transverse umbilical artery diameter or the ratio between umbilical vein and artery diameters can predict SUA, we found no significant improvement in the recognition of SUA using these parameters.

Adult↗
PubMed1997

Predicting birth weight by fetal upper-arm volume with use of three-dimensional ultrasonography.

OBJECTIVE: Our purpose was to determine the usefulness and accuracy of the three-dimensional ultrasonography assessed fetal upper-arm volume in predicting birth weight. STUDY DESIGN: From June 1996 to October 1996, we performed a prospective study of ultrasonography on 105 pregnant women without fetal structural anomaly or aneuploidy. Both the traditional two-dimensional ultrasonographic parameters and three-dimensional ultrasonography for fetal upper arm volume were measured within 48 hours of delivery. RESULTS: The upper arm volume correlated well with birth weight (r = 0.92, n = 105, p < 0.0001). With use of linear and polynomial regression, we obtained a best-fit new formula, Birth weight = 1088.60 + 36.024 x Upper-arm volume. The accuracy of this new formula is compared with that of two Chinese equations predicting fetal weight reported before and other formulas commonly used in the world as well. Our formula is more accurate in predicting birth weight than all the other formulas by traditional two-dimensional ultrasonography, either in error, percentage error, or absolute error. Another group by prospective validation further proved this finding. CONCLUSION: The upper-arm volume assessed by three-dimensional ultrasonography can accurately predict birth weight, and its accuracy is superior to the previous, formulas. Our study has at least validated the application of upper-arm volume by three-dimensional ultrasonography in estimating fetal weight. Further larger series are needed to confirm our findings.

Adult↗
PubMed1997

Three-dimensional ultrasound-assessed fetal thigh volumetry in predicting birth weight.

OBJECTIVE: To compare the accuracy of three-dimensional ultrasound-assessed fetal thigh volumetry in predicting birth weight with that of other commonly used formulas composed of biparietal diameter (BPD), abdominal circumference (AC), and femur length (FL) by two-dimensional ultrasound. METHODS: We assessed the thigh volume of 100 fetuses using three-dimensional ultrasound. Meanwhile, their BPD, AC, and FL were measured by two-dimensional ultrasound. All infants were delivered within 48 hours after the ultrasound examinations. From polynomial regression analysis, we generated a best-fit formula for the thigh volume to predict birth weight. The accuracy of this thigh-volume formula was compared with those of three formulas commonly used in the United States. In addition, another group of 50 fetuses was measured for prospective validation. RESULTS: The high volume assessed by three-dimensional ultrasound was highly correlated with birth weight (r = 0.89, n = 100, P < .0001). The best-fit formula for thigh volume to predict birth weight was linear, and it was superior to the other commonly used two-dimensional formulas in predicting birth weight. The predicting error (0 g), percent error (0.7%), absolute error (176.1 g), and absolute percent error (5.8%) of the thigh-volume formula were all smaller than those of the other formulas (n = 100, all P < .05). In addition, the thigh-volume formula predicted birth weight more accurately than the other two-dimensional formulas in the prospective-validation group. The three-dimensional formula had smaller mean values of predicting error (38.6 g), percent error (1.5%), absolute error (160.0 g), and absolute percent error (5.1%) than the two-dimensional formulas (n = 50, all P < or = .001), as well as the smallest variances of the above errors (178.1 g, 5.6%, 84.3 g, and 2.9%, respectively). CONCLUSION: The three-dimensional ultrasound-assessed thigh volume has better accuracy in predicting birth weight than the commonly used formulas by two-dimensional ultrasound, and it may improve fetal weight prediction in clinical practice. However, a large-scale prospective validation study may be needed to confirm our conclusions.

Adult↗
PubMed1997

Three-dimensional ultrasound assessment of fetal liver volume in normal pregnancy: a comparison of reproducibility with two-dimensional ultrasound and a search for a volume constant.

The purposes of this study are to compare the reproducibility of two-dimensional ultrasound (2DUS) and three-dimensional ultrasound (3DUS) in the assessment of fetal liver volume (LV), and to test whether the fetal LV assessed by the traditional method with 2DUS is equal to that with 3DUS in normal pregnancy. If significantly different, we then try to calculate a new constant of fetal LV for the traditional equation from the LV values obtained with 3DUS. In total, 30 normal singleton fetuses with gestational ages ranging from 20 to 30 weeks were included for the reproducibility test and 55 cases ranging from 20 to 31 weeks gestation were enrolled for finding a new volume constant of LV. The results showed that 3DUS is superior to 2DUS in the reproducibility test of fetal LV assessment. Moreover, the LV assessed with the traditional 2DUS method (identified as LV_42) was significantly smaller than that measured with 3DUS (P < 0.001). If the traditional 2DUS equation is to be used, the multiplying factor in the equation for the calculation of LV should be modified to 0.55 (SE = 0.017, N = 55). With the new volume constant, the new derived LV with 2DUS (identified as LV 55) was not different from that with 3DUS (identified as LV_3D). In conclusion, we recommend that 3DUS, instead of 2DUS, should be used for reaching an accurate assessment of fetal LV. Otherwise, applying our new volume constant may be of help in detecting abnormal fetal liver growth when only 2DUS is available.

Female↗
PubMed1997

Fetal heart volume assessment by three-dimensional ultrasound.

Heart volume may provide important information on the status of fetal hemodynamics. However, traditionally fetal heart volume has been assessed with the erroneous assumption that the fetal heart is spherical or elliptical. With the advent of three-dimensional ultrasound, accurate assessment of organ volume has become feasible. The objectives of this study were to compare the reproducibility of two-dimensional ultrasound and three-dimensional ultrasound in the assessment of heart volume, and to test whether heart volume assessed by the traditional method of two-dimensional ultrasound equates to that assessed by three-dimensional ultrasound. If it proved to be significantly different, we aimed to find a new constant which, if incorporated into the traditional formula used to determine heart volume, would enable us to achieve more accurate volumes with two-dimensional ultrasound. In total, 50 normal singleton fetuses ranging from 20 to 30 weeks' gestation were included in the study. Both the traditional two-dimensional and the new three-dimensional volume measurements were compared. The results showed that three-dimensional ultrasound has a better reproducibility than two-dimensional ultrasound in heart volume assessment and that heart volume assessed by the traditional formula of two-dimensional ultrasound is significantly larger than that measured by three-dimensional ultrasound (p < 0.001). We therefore propose that, if the traditional two-dimensional equation is to be used, the constant for heart volume could be modified to 0.4563 (SE = 0.0153, n = 50) to achieve more accurate results. With this new constant, the heart volume derived by two-dimensional ultrasound was not found to differ from that measured by three-dimensional ultrasound. From our series, we conclude that three-dimensional ultrasound is theoretically the best method for the assessment of heart volume. However, because of the limitations of three-dimensional ultrasound (i.e. it is not routinely available, it is more expensive and more time-consuming) two-dimensional ultrasound in practical terms should be the method of choice. Although we were able to improve the accuracy of the heart volume measurements using a new constant in the traditional two-dimensional formula, the new constant will not improve variability, which can only be reduced by three-dimensional ultrasound.

Cardiac Volume↗
PubMed1997

Prenatal diagnosis of ectopia cordis at 10 weeks of gestation using two-dimensional and three-dimensional ultrasonography.

We report here the earliest prenatal diagnosis to date of a case of ectopia cordis using both two-dimensional and three-dimensional ultrasound at 10 weeks of gestation. Both two-dimensional and three-dimensional ultrasound clearly revealed a thoracoabdominal ectopia cordis and an omphalocele. Histopathological examination confirmed the prenatal ultrasonic findings. In addition to an ectopia cordis, a supraumbilical hepato-omphalocele, absence of a pericardium and an anterior diaphragmatic defect were seen, although there was a normal sternum. These pathological findings, suggested that our case was a variant of pentalogy of Cantrell.

Adult↗
PubMed1997

Randomized comparison of misoprostol and dinoprostone for preinduction cervical ripening and labor induction.

This study attempts to evaluate the clinical effects of prostaglandin (PG) E analogues in preinduction cervical ripening and labor induction and to compare the perinatal outcomes of these medications. Sixty women with term singleton pregnancies were randomized to receive dinoprostone vaginal tablets (group I) or misoprostol vaginal tablets (group II). The Bishop scores were evaluated before drug insertion and every 4 hours during induction. Clinical data and perinatal outcomes were also recorded. There were no significant differences in the preinduction conditions on mean initial Bishop scores between these two groups. Twelve hours after drug insertion, the mean Bishop scores were significantly better in group II (9.7 +/- 3.1 vs 7.3 +/- 2.5, p < 0.05). The mean time from insertion to delivery was shorter in group II (16.5 +/- 2.7 h vs 25.7 +/- 3.8 h, p < 0.001). There were no significant differences in spontaneous labor rate, need for oxytocin augmentation, type of delivery, and Doppler flow velocity waveforms of the umbilical artery. The average number of doses given per patient was 1.8 +/- 1.4 in group II vs 2.7 +/- 0.3 in group I (p < 0.05). The perinatal outcome was similar in the two groups. In conclusion, misoprostol not only appears to be a safe and effective agent for cervical ripening and labor induction but is also more efficient than dinoprostone.

Adult↗
PubMed1997

Refined fetal abdominal growth assessment in normal pregnancy: Part I. Abdominal anteroposterior diameter.

BACKGROUND: The assessment of the adequacy of fetal growth by parameters other than the abdominal anteroposterior diameter (AAPD) of the fetus has been studied extensively. However the designs of these studies and the statistical methods used appears to deserve some criticism, based on present knowledge. Noncross-sectional cases selection, uncertainty of the fetal normality and inadequacy in statistical method, mostly ignored the changing property of each standard deviation (SD) of each gestational age (GA) which was proposed by Altman et. al. in 1993, are the three most common flaws in previous publishes. We tried to use AAPD with a strict study design as well as a reasonable statistical method to evaluate the fetal growth. METHODS: This study was performed in the Division of Maternal Fetal Medicine, National Cheng Kung University Hospital, Taiwan. The prenatal sonographic data of the fetuses were collected prospectively based on the following criteria: (1) accurate dating by knowing the maternal last menstration period (LMP) and early ultrasonography of the fetuses, (2) singleton pregnancy, (3) no fetal structural or chromosomal abnormality confirmed by prenatal ultrasonography and postnatal examination, (4) GA at birth was between 37 and 41 weeks' gestation, (5) no birth asphyxia, (6) appropriate birth body weight, and (7) no maternal medical disease or obstetrical complication which might predictably interfere with fetal growth. The collected data were analyzed by polynomial regression test and the best-fit equation for prediction of fetal growth was selected. The standard deviation (SD) of each GA was modeled before constructing the fetal growth centile charts by Altman's method. RESULTS: A total of 2077 cross-sectional sonographic data meeting the above criteria were collected for statistical analysis. The best-fit equation for the prediction of fetal GA by AAPD is GA = 20.8539 - 3.36743 x AAPD + 0.86927 x (AAPD)2 - 0.03789 x (AAPD)3 +/- k x [1.2533 x (0.36772 + 0.10938 x AAPD)], (r = 0.97287, p < 0.0001). The best-fit equation for prediction of fetal AAPD by GA is AAPD = -2.49495 + 0.38247 x GA - 1.07071 x 0.001 x (GA)2 +/- k x [1.2533 x (0.01760 + 0.01372 x GA)], r = 0.97122, p < 0.0001. The SD of AAPD for each complete GA was not the same. The fetal growth centile charts in the study are presented in this article. CONCLUSIONS: The SD of each complete GA changed with each specific GA. The GA of the fetus can be assessed accurately by measuring the AAPD alone. The utilization of these growth centile charts for evaluation of fetal growth is recommended.

Abdomen↗
PubMed1996

No association between alcoholism and multiple polymorphisms at the dopamine D2 receptor gene (DRD2) in three distinct Taiwanese populations.

This study examined whether there is evidence for an association between alcoholism and the alleles of the TaqI A, TaqI B, and short tandem repeat polymorphisms (STRP), both individually and as haplotypes, at the dopamine D2 receptor gene (DRD2) in males of three populations from Taiwan. We studied 46 Chinese Han (21 alcoholics and 25 nonalcoholics), 42 Atayal (21 alcoholics and 21 nonalcoholics), and 40 Ami (20 alcoholics and 20 nonalcoholics). Alcoholism was diagnosed according to DSM-III-R criteria and all individuals in the alcoholic groups were severely affected. Significant linkage disequilibrium occurs for the three polymorphic sites in all three populations. No significant association was observed between any of the three polymorphisms at the DRD2 locus, tested individually and as haplotypes, and alcoholism in the three subject groups. We conclude that no association exists between genetic variation at the DRD2 locus and alcoholism in Chinese Han, Atayal, and Ami males.

Adult↗
PubMed1996

The world-wide distribution of allele frequencies at the human dopamine D4 receptor locus.

The dopamine D4 receptor gene (DRD4) has an expressed polymorphism in the third exon that may have functional relevance. The polymorphism exists at two levels. At the higher level there is an imperfect tandem repeat of 48 base pairs (bp) coding for 16 amino acids; alleles have been identified with 2 (32 amino acids) to 10 (160 amino acids) repeats. The imperfect nature of the repeats is responsible for a more subtle level of variation since alleles with the same number of repeats can differ in the exact sequences or in the order of the variants of the 48-bp unit. We have undertaken a global survey of this expressed polymorphism as one approach to understanding the evolutionary significance and origins of the polymorphism as well as understanding what selective forces, if any, may be operating at this locus. As the first step, we have determined the repeat number genotype of the DRD4 repeat polymorphism in 1,327 individuals from 36 different populations. The allele frequencies differ considerably among the different populations. The 4-repeat allele was the most prevalent (global mean allele frequency = 64.3%) and appeared in every population with a frequency ranging from 0.16 to 0.96. The 7-repeat allele was the second most common (global mean = 20.6%), appearing quite frequently in the Americas (mean frequency = 48.3%) but only occasionally in East and South Asia (mean frequency = 1.9%). The 2-repeat allele was the third most common (global mean frequency = 8.2%) and was quite frequent in East and South Asia (mean frequency = 18.1%) while uncommon in the Americas (mean frequency = 2.9%) and Africa (mean frequency = 1.7%). The universality of the polymorphism with only three common repeat-number alleles (4, 7, and 2) indicates that the polymorphism is ancient and arose before the global dispersion of modern humans. The diversity of actual allele frequencies for this expressed polymorphism among different populations emphasizes the importance of population considerations in the design and interpretation of any association studies carried out with this polymorphism.

Africa↗
PubMed1996

Linkage disequilibrium between an allele at the dopamine D4 receptor locus and Tourette syndrome, by the transmission-disequilibrium test.

Dopaminergic abnormalities are implicated in the pathogenesis of Tourette syndrome (TS) and chronic multiple tics. We used the transmission-disequilibrium test (TDT) method to test for linkage disequilibrium between a specific allele (the seven-repeat allele (DRD4*7R) of the exon 3 VNTR polymorphic site) at the D4 dopamine receptor locus (DRD4) and expression of chronic multiple tics and TS. This particular allele had been shown in functional studies to have different binding properties compared with the other common alleles in this DRD4 polymorphic system. We studied 64 family trios (consisting of an affected person and two parents, at least one heterozygous for DRD4*7R), including 12 nuclear family trios and 52 trios from four large TS kindreds. The DRD4*7R allele was transmitted significantly more frequently than expected (chi 2 TDT ranging from 8.47 [P < .004] to 10.80 [P = .001], depending on breadth of disease definition and inclusion or exclusion of inferred genotypes). Confirmation of this finding will depend on either replication in other samples or the identification of a transmitted functional mutation within this sample.

Alleles↗
PubMed1996

[Operation directions by comparing financial ratio of 22 provincial hospitals].

Even more restrictive regulations and reimbursement limits seem to be a very heavy burden and stress for most provincial hospitals, especially after the National Health Insurance System has been introduced. The purpose of this project to find a better, universal direction for these hospitals through three steps: 1) Using different financial and accounting ratio indexes to evaluate the general business performance of each hospital. 2) Taking a comprehensive questionnaire with senior managers of each hospital to know their concepts and attitudes concerning external environment and internal operation. 3) Comparing data's correlation and differentiation to ascertain better trends for future operation for all hospitals. The database for this project comes from two resources: 1) Government finance and budget reports of 22 provincial hospitals for the 1994 accounting calendar year. 2) The results of questionnaires returned by 274 senior managers of hospitals, and analysis of these by chi-square test. Through statistical comparison, a number of conclusions can be made: 1) Most hospitals have better operation efficiency if any professional hospital administrator is working for them. 2) The hospital with more comprehensive personnel system shows better business performance. 3) The hospital with routine and formal financial analysis reports always has better business performance. 4) The hospital with poor operational efficiency tends to get rid of restriction or limitation from government's system. 5) The hospital with good operational efficiency has more confidence and desire to improve and change. 6) The hospital with poor operational efficiency is more dependent on outside support from government. 7) The hospital with better business performance has more concern about the impact of malpractice around the hospital. In short, a hospital with poor business efficiency always has more pessimistic attitude and tends to rely on outside resource support. On the other hand, a hospital with more confidence, flexibility and readiness for internal improvement always demonstrates greater business efficiency.

Economics, Hospital↗
PubMed1995

Acceleration time in normal fetal umbilical artery at term and its relationship to the cord blood hematocrit.

The purpose of this study was to test the hypothesis that the acceleration time (AT) of the fetal umbilical artery remains constant at term for normal pregnancies. In addition, we also examined whether the AT has any correlation with umbilical cord blood hematocrit (Hct). In total, 539 normal-term fetuses with menstrual ages (MA) ranging from 37 weeks to 42 weeks were enrolled in a cross-sectional design. The AT of the fetal umbilical artery was measured prior to delivery using a high-resolution, real-time Doppler scanner. All were delivered within 2 days of the ultrasound examination. At parturition, blood from the umbilical vein was collected and the red cell indices, including the Hct, were determined. The results indicated that the mean values of AT of the umbilical artery remained constant during normal-term pregnancies from 37 weeks to 42 weeks, menstrual age (mean: 0.104 sec, SE: 0.001 sec, n = 539). Although the AT was thought to be affected by the Hct, the AT had no correlation with umbilical venous Hct (n = 539, r = 0.002, p > 0.05). This constant value of the AT may be used as a reference for fetal physiology and perinatal medicine.

Acceleration↗
PubMed1995

Clinical trial of a combination of rice bran fiber and cholestyramine for promotion of fecal excretion of retained polychlorinated dibenzofuran and polychlorinated biphenyl in Yu-Cheng patients.

A clinical trial using the combination of rice bran fiber (RBF) and cholestyramine (CHO) was carried out on Yu-Cheng patients in 1993-1994. By the analysis of blood and stool samples collected from the patients before and after (or during in the case of stool), it was verified that the administration of RBF and CHO is effective for excretion of polychlorinated biphenyl (PCB) (p < 0.05) and polychlorinated dibenzofuran (PCDF), especially 2, 3, 4, 7, 8-pentachlorodibenzofuran (p < 0.05). However, the degree of effectiveness varied upon individual patients from 60 to 160% for 2, 3, 4, 7, 8-pentachlorodibenzofuran, from 30 to 110% for 1, 2, 3, 4, 7, 8-hexachlorodibenzofuran and from 50 to 190% for PCB, respectively.

Benzofurans↗
PubMed1995

[Levels of PCDDs, PCDFs and coplanar PCBs in the blood and stool of Taiwanese Yu-Cheng patients].

Levels of PCDDs, PCDFs and coplanar PCBs were measured in the blood and stool obtained from seventeen patients with Yu-Cheng in Taiwan. The average total concentrations of PCDDs, PCDFs and coplanar PCBs in the blood collected from Yu-Cheng patients in January 1993 and August 1994 were 590 and 570 pg Toxic Equivalents (TEQs)/g lipid, respectively. The concentrations of PCDDs, PCDFs and coplanar PCBs in the blood of patients were 21, 540 and 10 pg TEQs/g fat, respectively. On the other hand, the fecal excretion of PCDDs, PCDFs and coplanar PCBs were 26, 720 and 15 pg TEQs/day, respectively. The composition of congeners in the feces was quite similar to the one in the blood. The half lives were estimated as 9.1 and 8.6 years for 2, 3, 4, 7, 8-pentachlorodibenzofuran and 1, 2, 3, 4, 7, 8-hexachlorodibenzofuran based on fecal excretion, respectively.

Asian People↗
PubMed1994

The adverse effect on fetal hemogram by preeclampsia: marked anisocytosis with normocytic, normochromic erythrocythemia as well as thrombocytopenia.

Whether preeclampsia affects the fetal hematologic system still remains a controversial issue. The purpose of this series was to examine the hypothesis that preeclampsia may or may not cause adverse effects on fetal hemogram, including erythrocytes, leukocytes, and platelets. In addition, no one, to date, has reported the effect on red cell distribution width (RDW) of fetal cord blood by preeclampsia. Therefore this series also tested the hypothesis that preeclampsia may induce elevation of RDW in fetal cord blood. From August 1, 1989 to July 31 1990, we prospectively collected cord blood samples at parturition from 21 preeclamptic pregnancies and 366 uncomplicated controls and measured their complete blood counts by computerized blood autoanalyzer. The results of the comparison with red blood cells showed significant erythrocythemia (P < 0.05), increased hematocrit (P < 0.05), elevated hemoglobin (P < 0.05), and marked anisocytosis (as reflected by RDW, P < 0.0001) in preeclamptic pregnancies than in controls. Though no significant differences were demonstrated in the white cell counts, severe thrombocytopenia (P < 0.001) was observed in the preeclamptic group than in controls. We concluded that preeclampsia may cause significant normocytic, normochromic erythrocythemia, marked anisocytosis and severe thrombocytopenia in newborns, which deserved the attention of obstetricians and neonatologists. Further studies are warranted to elucidate the underlying pathophysiological mechanisms.

Erythrocyte Count↗