Tumor necrosis factor-alpha converting enzyme in the human placenta throughout gestation

Ectodomain shedding of epidermal growth factor receptor ligands such as transforming growth factor- alpha (TGF-alpha), heparin-binding epidermal growth factor-like growth factor (HBEGF), and amphiregulin (AREG) is considered to be important during implantation. Tumor necrosis factor-alpha converting enzyme (TACE) has been suggested as the major sheddase for these molecules. The objectives of this study are (1) to characterize the expression of TACE in the human placenta throughout gestation; (2) to determine the association between the expression of TACE with TGF-alpha, HBEGF, and AREG; (3) to ascertain whether TACE mediates TGF-alpha, HBEGF, and AREG shedding; and (4) to examine the effect of hypoxia on the expression of TACE. By analyzing a total of 55 villous samples representing different gestational ages, the authors found that TACE was continuously expressed in the placentas throughout gestation and that the levels of TACE were positively correlated with the levels of TGF-alpha, HBEGF, and AREG. Preadministration of a TACE inhibitor in villous explant cultures or transfection of cytotrophoblastic cells with TACE-specific small interference RNA decreased the shedding of HBEGF and AREG. Moreover, hypoxia (2% O(2)) caused an increase in the levels of TACE mRNA and protein in villous explants and primary cytotrophoblastic cells in vitro. These results indicate that oxygen regulates the expression of TACE and that TACE may be important for placental development during human pregnancy.     

Triterpenoids from the leaves of Diospyros kaki (persimmon) and their inhibitory effects on protein tyrosine phosphatase 1B

Phytochemical study on a methanol-soluble extract of the leaves of persimmon (Diospyros kaki) resulted in the isolation of two new ursane-type triterpenoids, 3alpha,19alpha-dihydroxyurs-12,20(30)-dien-24,28-dioic acid (1) and 3alpha,19alpha-dihydroxyurs-12-en-24,28-dioic acid (2), together with 12 known ursane- and oleanane-type triterpenoids (3-14). Triterpenoids with a 3beta-hydroxy group were found to inhibit protein tyrosine phosphatase 1B (PTP1B) activity, with IC50 values ranging from 3.1+/-0.2 to 18.8+/-1.3 microM, whereas those with a 3alpha-hydroxy moiety were not active.     

Therapeutic effects of baicalin on lipopolysaccharide-induced acute lung injury in rats

Baicalin is a flavonoid present in many traditional Chinese medicines. A number of studies show that baicalin has anti-inflammatory actions and protects against a variety of tissue and organ injuries. The effect of baicalin in lipopolysaccharide (LPS)-induced acute lung injury is not well studied. In this study, typically acute lung injury was induced in rat by intratracheal injection of LPS, which increased lactate dehydrogenase activity and protein content in bronchoalveolar lavage fluid, wet/dry lung weight ratio, Evan's blue dye leakage, and neutrophil infiltration. Baicalin (20 mg/kg) was administrated 1 hour before or 30 min after LPS injection. Both pre and post-treatment with baicalin attenuated the increase of these parameters and improved histological finding. Our results suggest that baicalin has a therapeutic effect on LPS-induced acute lung injury.     

Fetal nasal bone length and Down syndrome during the second trimester in a Chinese population

Objective:  The purpose of the present study was to build a database of reference ranges of fetal nasal bone length (NBL) in a Chinese population. The accuracy rate of detecting Down syndrome was also analyzed using fetal NBL as a marker.
Methods:  The control group of fetuses included 342 normal singleton pregnancies with no chromosomal or congenital anomalies. The present study was a cross-section study and the control group was used to construct percentile values of NBL from 13 to 29 gestational weeks of age. Two-dimensional ultrasonography was used for the nasal bone studies. Measurements of NBL were collected and each fetus contributed a single value to the reference sample. During the study period, 14 fetuses with Down syndrome were examined. Measurement of fetal NBL was made during amniocentesis, with gestational age ranging from 13 to 19 weeks.
Results:  From 342 normal fetuses with gestational age ranging from 13 to 29 weeks, reference ranges of NBL were constructed. The reference ranges were constructed from the 100(1 − p)% reference range:     , where Ŷ  = 25 − exp(3.58 − 0.044 ×  t  + 0.0006 ×  t ²), with Ŷ being the fitted mean of regression model and t being gestational age (weeks). Using fetal NBL, the regression model was Pr (Down syndrome) = exp( W )/[1 + exp( W )], where W  = 0.62–4.80 × NBL (multiples of the median) in predicting Down syndrome. Fetal NBL was found to have a sensitivity and specificity of 0.78 and 0.78, respectively, in predicting Down syndrome in the second trimester of pregnancy.
Conclusions:  Fetal NBL measurement can provide a simple and useful algorithm to predict Down syndrome during the second trimester of pregnancy.     

Group B streptococcus infection in pregnancy

Group B streptococcus (streptococcus agalactiae), a gram-positive coccus, is one of the major causes of maternal or neonatal severe infection and sepsis. Maternal infection associated with GBS includes acute chorioamnionitis, endometritis, and urinary tract infection.