BIG NEWS FROM SCIENCE

Surgeons have successfully replaced a patient’s skull with a 3D-printed version. Three months after the operation the patient, a 22-year-old woman with a rare disorder that thickened her skull and gave her poor eyesight as well as headaches, has recovered her eyesight and has gone back to work.

Read more: http://ind.pn/1pecfoe via The Independent

posted from Bloggeroid

OVERVIEW OF THE IMMUNE SYSTEM

The immune system is a complex system that is responsible for protecting us against infections and foreign substances. There are three lines of defense: the first is to keep invaders out (through skin, mucus membranes, etc), the second line of defense consists of non-specific ways to defend against pathogens that have broken through the first line of defense (such as with inflammatory response and fever). The third line of defense is mounted against specific pathogens that are causing disease (B cells produce antibodies against bacteria or viruses in the extracellular fluid, while T cells kill cells that have become infected). The immune system is closely tied to the lymphatic system, with B and T lymphocytes being found primarily within lymph nodes. Tonsils and the thymus gland are also considered lymph organs and are involved in immunity. We often don't realize how effective the immune system is until it fails or malfunctions, such as when the lymphocytes are attacked by HIV in an AIDS patient.

HUMAN CHORIONIC GONADOTROPHIN

Human chorionic gonadotrophin (HCG) is synthesised early in pregnancy by the newly formed trophoblasts and is secreted into the maternal circulation. It can be detected as early as the eighth day after conception (this property help in quick detection of pregnancy) and its levels in the maternal blood continue to rise rapidly, reaching peak levels at about 10-12 weeks of gestation. HCG measurements have long been used to confirm pregnancy and many "home-test" kits are widely available. Pregnancy kits detecting urine HCG are not as sensitive as those measuring plasma or serum HCG levels the glycoprotein is rapidly metabolised by the liver and kidneys and only a small fraction is excreted unchanged in the maternal urine. HCG has luteotrophic activity and is responsible for maintaining the viability of the corpus luteum into early pregnancy. It may also be responsible for inducing testosterone secretion by the fetal testes before the fetal pituitary is ready to secrete luteinising hormone. Serum HCG titres are also used in the investigation of a probable ectopic pregnancy high titres suggest it as the cause of acute abdominal pain, which is usually the presenting symptom. HCG is also produced by tumours of the trophoblast and thus can occur in males (e.g., testicular teratocarcinoma) and non-pregnant females (e.g., hydatidiform mole and choriocarcinoma).

INSIGHT ON WILEON'S DISEASE

Wilson's disease is an inborn error of copper metabolism characterised by deposition of copper in, and damage to, the liver (cirrhosis), brain basal ganglia, proximal renal tubule (Fanconi syndrome), and the cornea of the eye (Kayser-Fleischer rings). The plasma caeruloplasmin level is usually low and the urinary copper level high, reflecting the high level of plasma free copper. The definitive diagnosis depends on demonstration of excess copper in the liver.