ABSTRACT
Drug use during pregnancy is unavoidable. Therefore, it is vitally important for medical workers to help pregnant women take drugs correctly to reduce the incidence of spontaneous abortion, premature birth, and low birth weight. In our study, drug screening model with induced pluripotent stem cells (iPSCs) was used to find some improper drugs which will result in woman's abortion. With 3D culture in vitro, iPSCs can form embryoid bodies (EBs) and cerebral organoids, which simulated in vitro development of early embryos, from inner cell mass to germ-layer differentiation. In the experiment, EBs were exposed to mifepristone (RU486), and three experimental groups were divided randomly. They were control group (without RU486), low-dose group (L-RU486, 10 μg·mL-1), and high-dose group (H-RU486, 20 μg·mL-1). After mifepristone exposure, EBs were observed at days 5, 8, and 11, including size of EB, cell apoptosis, and differentiation of germ layers, by using inverted optical microscope, TUNEL assay, and immunofluorescent staining. The results showed that through 3D culture, iPSCs could develop into embryoid bodies, neural rosettes, and finally cerebral organoids. After mifepristone exposure, EBs' sizes were decreased (P < 0.01); the levels of cell apoptosis in EBs were increased after mifepristone exposure (P < 0.01); the development of EBs' germ layer was affected. Mifepristone exposure could inhibit the proliferation of embryonic stem cells, reduce the differentiation of ectoderm (P < 0.01) and promote the development of mesoderm (P < 0.05). In conclusion, iPSCs can be used as a screening model for abortion drug, and EBs’ diameter, cell apoptosis, and differentiation changes of the germ layers can serve as criteria of abortion drug screening.
ABSTRACT
BACKGROUND AND OBJECTIVEThe novel coronavirus (SARS-Cov-2) infected coronavirus disease 2019 (COVID-19) was broken out in Wuhan and Hubei province for more than a month. It severely threats peoples health of thousands in Chin and even other countries. In order to prevent its wide spread, it is necessary to understand the development of the epidemic with precise mathematical language. METHODSThe various data of novel coronavirus pneumonia were collected from the official websites of the National Health Committee of the Peoples Republic of China. According to epidemic and administrative division, three groups were divided to analyze the data, Hubei Province (including Wuhan), nationwide without Hubei and Henan Province. With classic SIR models, the fitting epidemiological curves of incidence have made, and basic reproduction number (R0) was also calculated as well. Therefore the diseases infection intensity, peak time and the epidemiological end time can be deduced. RESULTS(1) Wuhan was the origin place of the epidemic, then it spread to Hubei province quickly. The patients in Hubei had increased rapidly with exponential rise. According to data in Hubei province, the fitting parabolas were made, and some with 51,673 cases. R0 curve shows with S-curve, at early breakout, R0 was as high as 6.27, then it decrease gradually. It is expected to approach to zero in early May; (2) In the group of nationwide without Hubei, the patient cases were much lower than Hubei, but its epidemiological fitting curve also shows a parabola as Hubei. The peak will arrive around February 10 with 9,145 cases. At beginning, R0 was as high as 2.44, then it decreases gradually and approach to zero in the end of March. (3) In Henan Province, the incidence stays very low, the parabolic fitting curve is similar to the nationwide without Hubei. The epidemic is expected to reach the peak on around February 12 and end in early April. CONCLUSIONThe epidemic development in all three groups shows parabolic curves. Their incidences are expected to reach their peaks on February 18 in Hubei, on February 10 in other areas of China. The epidemic will end in early May in Hubei, and in early April in other areas of China. Our study may provide useful knowledge for the government to make prevention and treatment policies.
ABSTRACT
<p><b>OBJECTIVE</b>To study the role of non-nutritive sucking in preterm infants requiring mechanical ventilation therapy.</p><p><b>METHODS</b>In a study of 68 preterm infants requiring mechanical ventilation, a randomly selected observation group of 35 infants was provided with non-nutritive sucking and a control group of 33 infants was not. The time to reach full enteral feeding, birth weight recovery time, body weight growth rate, hospitalization time, feeding tolerance and mechanical ventilation-related complications were compared between the two groups.</p><p><b>RESULTS</b>The time to reach full enteral feeding and hospitalization time were shorter (P<0.01), the incidence of feeding intolerance was lower (P<0.05), and the body weight growth rate was higher (P<0.05) in the observation group than in the control group. There were no significant differences in the birth weight recovery time and the incidence of mechanical ventilation-related complications between the two groups.</p><p><b>CONCLUSIONS</b>The use of non-nutritive sucking can increase growth rate, shorten hospitalization time and improve feeding tolerance in preterm infants requiring mechanical ventilation therapy. Moreover, it does not result in an increase in mechanical ventilation-related complications.</p>
