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J C Shih

Publications and source records attributed to J C Shih.

185 records · Page 11Linked to original sources
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Second trimester maternal serum hCG level in an Asian population: normal reference values by ultrasound dating.

OBJECTIVE: To establish normative data of maternal serum chorionic gonadotropin (hCG) during the second trimester in an Asian population. METHODS: We measured the maternal serum hCG levels in 17,955 normal singleton pregnancies between 15 and 21 weeks of gestation. The gestation age was estimated by measurement of fetal biparietal distance (BPD) in all cases. Median values of hCG at various gestational weeks were calculated and the values of hCG were converted to multiple of median (MoM). The incidences of low MoM value and high MoM value were also calculated. RESULTS: The mean and median values of hCG were 57,153 mIU/ml and 50,120 mIU/ml, respectively, at 15 weeks of gestation and then decreased to 30,898 mIU/ml and 26,226 mIU/ml, respectively, at 21 weeks. We found 8.6% and 9.4% of normal singleton pregnancies have hCG MoM values >2.0 MoM and <0.5 MoM, respectively. CONCLUSIONS: Our report provides a normal reference data of second trimester maternal hCG levels by ultrasound dating in an Asian population.

Chorionic Gonadotropin↗
PubMedDate not supplied

Maternal serum screening for down syndrome by using alpha-fetoprotein and human chorionic gonadotropin in an asian population. a prospective study.

The purpose of the present study is to evaluate the efficacy of second-trimester maternal serum screening program by using alpha-fetoprotein (AFP) and total human chorionic gonadotropin (hCG) in an Asian population. During June 1994 to July 1998, we conducted a prospective study of serum screening protocol for Down syndrome. The cut-off point for a positive result in this analysis was a risk of >/=1/270. A total of 17,742 pregnant women with singleton pregnancy were screened, and 1,153 (6.5%) had positive result. Sixteen of the 17,742 pregnancies had Down syndrome, and 10 of them had positive result. The positive rate and detective rate for Down syndrome were 6.5 and 62.5%, respectively. However, the detective rate will reduce to 47.6% after being adjusted by age-specific risk. It is indicated that the double-marker test using AFP and total hCG is an effective screen strategy for second-trimester detection of Down syndrome in Asian women.

Adult↗
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Role of MAO A and B in neurotransmitter metabolism and behavior.

MAO (monoamine oxidase) A and B are key isoenzymes that degrade biogenic and dietary amines. MAO A preferentially oxidizes serotonin (5-hydroxytryptamine, 5-HT) and norepinephrine (NE), whereas MAO B preferentially oxidizes phenylethylamine (PEA). Both forms can oxidize dopamine (DA). However, the substrate specificity overlap and the in vivo function of these two isoenzymes is not clear. Recently, we have shown that MAO A and B knock-out (KO) mice exhibit distinct differences in neurotransmitter metabolism and behavior. MAO A KO mice have elevated brain levels of 5-HT, NE and DA and manifest aggressive behavior similar to men with a deletion of MAO A. In contrast, MAO B KO mice do not exhibit aggression and only levels of PEA are increased. Both MAO A and B KO mice show increased reactivity to stress. Taken together, these results suggest that MAO A and B have distinctly different roles in monoamine metabolism. Further, these mice are valuable models for investigating the role of monoamines in psychoses and neurodegenerative and stress-related disorders.

Aggression↗