Objective To investigate the values of ultrasound measuring of the placenta thickness on evaluation of risks for alpha-thalassemia at the early pregnancy.Methods Two-dimensional ultrasound was performed to measure the thickness of placenta on 208 cases of fetuses with alpha-thalassemia and 52 cases of normal fetuses in control group.The placenta thickness was expressed as multiples of the median(MOM).Results At the early pregnancy,the group of fetuses with alpha-thalassemia had significantly higher placenta thickness compared to the fetuses without alpha-thalassemia(P＜0.001).However,there were no statistical significant difference in the placenta thickness between the other groups(P=0.100).Placenta thickness 1.18 MOM was the best critical point to predict alpha-thalassemia.The sensitivity and specificity of placenta thickness >1.18 MOM in prediction of alpha-thalassemia was 82.9%,84.7% respectively.Conclusions For those with high risks of alpha-thalassemia placenta thickness measuring is a safe,effective parameter for assessment because it could reduce unnecessary invasive procedures and improve the detecting rate of severe alpha-thalassemia.

OBJECTIVE: To determine the carrier rate of Fragile X mental retardation 1 gene (FMR1) mutants in women with a history of adverse pregnancy or childbirth, and to provide prenatal diagnosis for the carriers. METHODS: Peripheral blood samples were collected from women with a history of adverse pregnancy or childbirth, and the FMR1 gene cytosine-guanine-guanine repeat number (CGG)n was determined by triple-repeat primer polymerase chain reaction (TP-PCR) combined with capillary electrophoresis. Prenatal diagnosis was provided for the carriers during pregnancy. RESULTS: Among 819 samples, 9 gray zone repeats carriers and 10 premutation carriers were detected, which gave a prevalence of 1 in 91 and 1 in 82, respectively, with a total prevalence of 1 in 43. Prenatal diagnosis was provided during 7 pregnancies for 6 carriers. A female fetus with premutation (n = 30/57) and an affected male fetus with full mutation (n = 336) were detected. CONCLUSION FMR1 gene testing in women with a history of adverse pregnancy or childbirth can facilitate genetic counseling and reproductive guidance for carriers of gray zone repeats and premutations. Prenatal diagnosis for carriers of premutation can facilitate reduction of the birth of children with fragile X syndrome.

Objective:To investigate the colonscopy screening interval among patients with negative colonscopy.Methods:We selected 14 606 participants who completed the baseline and 3-year or 5-year colonoscopy examinations in the American Prostate, Lung, Colorectal, and Ovarian (PLCO) dataset as the target population. Sociodemographic characteristics (i.e., sex, age, marital status, race, and smoking), lifestyle, family history of cancer, and family history of colorectal cancer were collected. Cochran-Armitage trend analysis was used to examine whether the rate of positive cases (colorectal cancer, advanced adenoma, adenoma, and hyperplastic polyp) was increased with the length of screening interval. We compared the differences in number of detected cases, positive rates, and proportions of 3-year and 5-year screening interval strategies using internal standardization method.Results:The age of the population was （61.9±5.2） years and over half of them were males (54.4%) and 46.2% had family cancer history. The mean screening interval between the first and second endoscopies was （1 639.1±320.9） days. A total of 1 716 cases had positive endoscopic findings. With the screening interval extended, rate of the screened positive cases was also increased ( P for trend<0.001). After standardized by the internal standardized population (14 606), 17.99 and 11.57 colorectal cancer cases and 177.37 and 240.35 advanced adenoma cases were detected by 3-year and 5-year screening interval strategies, respectively. Conclusion:Based on the initial screening negative population of colonoscopy in the United States, the 3-year screening interval strategy could detect a relatively large number of colorectal cancer cases, but its health and economic evaluation needs to be further explored.

Objective:To investigate the colonscopy screening interval among patients with negative colonscopy.Methods:We selected 14 606 participants who completed the baseline and 3-year or 5-year colonoscopy examinations in the American Prostate, Lung, Colorectal, and Ovarian (PLCO) dataset as the target population. Sociodemographic characteristics (i.e., sex, age, marital status, race, and smoking), lifestyle, family history of cancer, and family history of colorectal cancer were collected. Cochran-Armitage trend analysis was used to examine whether the rate of positive cases (colorectal cancer, advanced adenoma, adenoma, and hyperplastic polyp) was increased with the length of screening interval. We compared the differences in number of detected cases, positive rates, and proportions of 3-year and 5-year screening interval strategies using internal standardization method.Results:The age of the population was （61.9±5.2） years and over half of them were males (54.4%) and 46.2% had family cancer history. The mean screening interval between the first and second endoscopies was （1 639.1±320.9） days. A total of 1 716 cases had positive endoscopic findings. With the screening interval extended, rate of the screened positive cases was also increased ( P for trend<0.001). After standardized by the internal standardized population (14 606), 17.99 and 11.57 colorectal cancer cases and 177.37 and 240.35 advanced adenoma cases were detected by 3-year and 5-year screening interval strategies, respectively. Conclusion:Based on the initial screening negative population of colonoscopy in the United States, the 3-year screening interval strategy could detect a relatively large number of colorectal cancer cases, but its health and economic evaluation needs to be further explored.