ABSTRACT
Objective Amniotic fluid chromosome karyotype analysis is the golden standard for prenatal diagnosis of chromosome diseases, but its success rate is low due to many factors affecting amniotic fluid culture. The research aimed to investigate the relevant factors influencing the success rate of amniotic fluid cell in situ culture and explore the condition of karyotype preparation in order to establish a stable method to prepare amniotic fluid cell chromosome with high success rate. Methods Cell culture was done in amniotic fluid obtained from 435 pregnant women with prenatal diagnosis indications by amniocentesis. Statistical analysis was done on the relationship between the amount of amniotic fluid after centrifugal precipitation, the material of operation apparatus and the culture result, as well as the relationship between ambient temperature and humidity and karyotype dispersion degree. Results Successful culture was obtain in 406 cases out of 435 cases, with the success rate being 93.3%. According to the culture result, compared with white cell mass group, the culture success rates were significantly reduced in mass brown cell group and mass fresh red cell group (P<0.01). Compared with mass fresh red cell group, the culture success rate was significantly reduced in small fresh red cell group (P<0.01). Compared with the plastic group, the culture success rate was significantly increased in glass group (P<0.01). Compared with the plastic injector and other glass group, the culture success rate was significantly improved in glass group (P<0.05). The score of the karyotype dispersion degree showed slides made at 28℃of room temperature and 50% humidity were significantly better than those made at room temperature and humidity, 28℃ of room temperature and room humidity, room temperature and 50% humidity (P<0.01). Slides made at room temperature and 50% humidity were significantly better than those at room temperature and humidity, and 28℃ of room temperature and room humidity (P<0.01). Conclusion The methods including improving the technological level of amniocentesis, handling bloody amniotic fluid timely and correctly, and the application of glass injectors and other apparatus, can effectively improve the success rate of amniotic fluid cell culture. Controlling the environmental temperature and humidity (28℃,50%) in dispersion course contributes to qualified slides for karyotype analysis, providing safeguard for prenatal diagnosis.
ABSTRACT
<p><b>OBJECTIVE</b>To explore the mechanism and effect of maternal high-fat diet before and during pregnancy on bone growth of neonatal offspring rats.</p><p><b>METHODS</b>Forty female Sprague-Dawley rats were divided into high-fat diet and control groups (n=20) that were fed with 35% high-fat diet and standard chow, respectively. After 8 weeks, 8 female rats from each group were sacrificed for liver pathological examinations and the other female rats were mated with male rats and fed continuously with 35% high-fat diet and standard chow throughout gestation, respectively. The body lengths (from apex nasi to end of tail) of the offspring rats from both groups were measured within 24 hours after birth. Enzyme-linked immunosorbent assay was used to detect serum insulin-like growth factor (IFG-I) levels. Liver pathological changes were observed under a light microscope. The expression of insulin receptor substrate 1 (IRS-1) and phosphorylation IRS-1 (Phospho-IRS-1) in tibia and femur samples were detected by immunohistochemistry. The expression of mitogen-activated protein kinase (MAPK) and phosphorylation MAPK (Phospho-MAPK), phosphatidylinositol 3-kinase (PI3K) and phosphorylation PI3K (Phospho-PI3K), protein kinase B (AKT1) and phosphorylation AKT1 (Phospho-AKT1) in tibia and femur samples were detected by Western blot.</p><p><b>RESULTS</b>The offspring rats from the high-fat diet group showed a significant shorter body length compared with those from the control group (P<0.05). The level of serum IGF-I in offspring rats from the high-fat diet group decreased by 20.1% in comparison to those from the control group, but there was no significant difference between the two groups (P>0.05). Fatty degeneration was found in livers of both high-fat diet-fed maternal rats and their offspring rats under a light microscope. There were no significant differences in IRS-1 and Phospho-IRS-1 expression in chondrocytes of tibia and femur samples between the offspring rats of the two groups (P>0.05). The protein expression of MAPK in chondrocytes of tibia and femur samples of offspring rats from the high-fat diet group was higher than that from the control group (P<0.05). There were no significant differences of PI3K and AKT1/Phospho-AKT1 between the offspring rats of the two groups (P>0.05).</p><p><b>CONCLUSIONS</b>A maternal high-fat diet before and during pregnancy may affect the bone growth of offspring rats in utero, which is possibly associated with the decreased IGF-I level. However, further study on the exact mechanism of IGF-I on the bone growth is needed.</p>