Human placental lactogen

Human placental lactogen (hPL), also called human chorionic somatomammotropin (HCS), is a polypeptide placental hormone, the human form of placental lactogen (chorionic somatomammotropin). Its structure and function are similar to those of human growth hormone. It modifies the metabolic state of the mother during pregnancy to facilitate the energy supply of the fetus. hPL has anti-insulin properties. hPL is a hormone secreted by the syncytiotrophoblast during pregnancy. Like human growth hormone, hPL is encoded by genes on chromosome 17q22-24. It was identified in 1963.

Structure

hPL molecular mass is 22,125 and contains single chain consisting of 191 amino acid residues that are linked by two disulfide bonds and the structure contains 8 helices. A crystal structure of hPL was determined by X-ray diffraction to a resolution of 2.0 Å.

Levels

hPL is present only during pregnancy, with maternal serum levels rising in relation to the growth of the fetus and placenta. Maximum levels are reached near term, typically to 5–7 mg/L. Higher levels are noted in patients with multiple gestation. Little hPL enters the fetal circulation. Its biological half-life is 15 minutes.

Premier League

The Premier League is an English professional league for men's association football clubs. At the top of the English football league system, it is the country's primary football competition. Contested by 20 clubs, it operates on a system of promotion and relegation with the Football League. Welsh clubs that compete in the English football league system can also qualify.

The Premier League is a corporation in which the 20 member clubs act as shareholders. Seasons run from August to May. Teams play 38 matches each (playing each team in the league twice, home and away), totalling 380 matches in the season. Most games are played on Saturday and Sunday afternoons; others during weekday evenings. It is currently sponsored by Barclays Bank and thus officially known as the Barclays Premier League and is colloquially known as the Premiership. Outside the UK it is commonly referred to as the English Premier League (EPL).

The competition formed as the FA Premier League on 20 February 1992 following the decision of clubs in the Football League First Division to break away from the Football League, which was originally founded in 1888, and take advantage of a lucrative television rights deal. The deal was worth £1 billion a year domestically as of 2013–14, with BSkyB and BT Group securing the domestic rights to broadcast 116 and 38 games respectively. The league generates €2.2 billion per year in domestic and international television rights. In 2014/15, teams were apportioned revenues of £1.6 billion.