Seasonality of fetal trisomy 21--have ambient air pollutants played a role?

Objective: To examine the seasonality of fetal trisomy 21 and its relationship with ambient air pollutants.

Methods: The averaged incidence by month-of-conception of the 113 cases (2002-2009) in our registry was correlated with month of conception and monthly ambient levels of nitrogen oxides (NOx, NO and NO2), sulfur dioxide, carbon monoxide, and ozone as reported by the Hong Kong Environmental Protection Department at the month of, and four-week after, conception.

Results: The incidence was highest in February (3.

Environmental factors in the first trimester and risk of oral-facial clefts in the offspring.

The averaged incidences of nonsyndromal/isolated cleft lip (CL), cleft palate (CP), and cleft lip with cleft palate (CLCP) by each month-of-conception, and managed in our hospital in from 2002 to 2009 were correlated with the reported levels of sunshine, ultraviolet radiation, and ambient nitrogen oxides (nitrogen oxide, nitrogen monoxide, and nitrogen dioxide), sulfur dioxide, and ozone, at the month of, and then at 4 and 8 weeks after, conception. There were 25, 12, and 22 cases each of CL, CP, and CLCP, respectively, totaling 59 cases (1.21 of 1000 births).

Is there Seasonality in the Incidence of Oral-Facial Clefts?

Abstract Objective: To determine if seasonal variation in the incidence of oral-facial clefts exists in the Hong Kong Chinese population. Methods: Cases of non-syndromal oral-facial clefts identified from the Prenatal Diagnostic Clinic database from 2002-2009, and total births from our departmental statistics during this period, were used to calculate the averaged month-of-conception incidence for overall cases and individual categories of clefts, including cleft lip (CL), cleft palate (CP), cleft lip with/without cleft palate (CL+/-CP), and cleft lip with cleft palate (CLP). Results: There were 59 eligible cases (1.

Isolated absent or hypoplastic nasal bone in the second trimester fetus: is amniocentesis necessary?

Objective: To elucidate the significance of isolated absent or hypoplastic nasal bone in the second trimester ultrasound scan.

Methods: All cases of absent or hypoplastic nasal bone (length < 5th percentile) encountered during 2007-2009 were retrieved from database and all the ultrasound findings including structural abnormalities and soft markers for Down syndrome and fetal karyotype were reviewed. The cases were categorized into a study group with isolated absent or hypoplastic nasal bone and a comparison group with additional ultrasound findings.

Zona pellucida-induced acrosome reaction in human spermatozoa is potentiated by glycodelin-A via down-regulation of extracellular signal-regulated kinases and up-regulation of zona pellucida-induced calcium influx.

Background: Glycodelin-A interacts with spermatozoa before fertilization, but its role in modulating sperm functions is not known. Zona pellucida-induced acrosome reaction is crucial to fertilization and its dysfunction is a cause of male infertility. We hypothesized that glycodelin-A, a glycoprotein found in the female reproductive tract, potentiates human spermatozoa for zona pellucida-induced acrosome reaction.

Cumulus-associated alpha2-macroglobulin derivative retains proconceptive glycodelin-C in the human cumulus matrix.

Background: Glycodelin-C is a glycodelin isoform isolated from the cumulus matrix. It stimulates spermatozoa-zona pellucida binding. Here, we report the isolation and characterization of a novel glycodelin interacting protein (GIP) from human cumulus matrix.

Effects of differential glycosylation of glycodelins on lymphocyte survival.

Glycodelin is a human glycoprotein with four reported glycoforms, namely glycodelin-A (GdA), glycodelin-F (GdF), glycodelin-C (GdC), and glycodelin-S (GdS). These glycoforms have the same protein core and appear to differ in their N-glycosylation. The glycosylation of GdA is completely different from that of GdS.

Complement 3 deficiency impairs early pregnancy in mice.

Human oviductal cells produce complement-3 (C3) and its derivative, iC3b. These molecules are important in immune responses. Our recent study suggested that iC3b also possessed embryotrophic activity and it stimulates the blastulation and hatching rates of in vitro cultured mouse embryos.

Effects of native human zona pellucida glycoproteins 3 and 4 on acrosome reaction and zona pellucida binding of human spermatozoa.

Acrosome reaction is crucial to the penetration of spermatozoa through the zona pellucida (ZP). Glycosylation of ZP glycoproteins is important in spermatozoa-ZP interaction. Human ZP glycoprotein-3 (ZP3) is believed to initiate acrosome reaction.

Cumulus oophorus-associated glycodelin-C displaces sperm-bound glycodelin-A and -F and stimulates spermatozoa-zona pellucida binding.

Spermatozoa have to swim through the oviduct and the cumulus oophorus before fertilization in vivo. In the oviduct, spermatozoa are exposed to glycodelin-A and -F that inhibit spermatozoa-zona pellucida binding. In this study, we determined whether these glycodelins would inhibit fertilization.

Glycodelin-A interacts with fucosyltransferase on human sperm plasma membrane to inhibit spermatozoa-zona pellucida binding.

Fertilization depends on successful binding of the spermatozoa to the zona pellucida of the oocyte. Glycodelin-A inhibits spermatozoa-zona pellucida binding. Previous data showed that glycodelin-A receptor(s) and zona pellucida protein receptor(s) on human spermatozoa are closely related.

Glycodelin-S in human seminal plasma reduces cholesterol efflux and inhibits capacitation of spermatozoa.

Tight control of sperm capacitation is important for successful fertilization. Glycodelin-S is one of the most abundant glycoproteins in the human seminal plasma. However, its function is unclear.

Phospholipid transfer protein (PLTP) mRNA expression is stimulated by developing embryos in the oviduct.

In mammal, fertilization and early preimplantation embryo development occurs in the oviduct. Evidence is accumulating that the oviductal epithelia secrete various biomolecules to the lumen during the secretory phase of the estrus cycle to enhance embryo development. This secretory activity of the oviduct is under the regulation of steroid hormones.