According to the Global Terrorism Database, the most active terrorist group in the period 1970 to 2010 was Shining Path (with 4,517 attacks), followed by Farabundo Marti National Liberation Front (FMLN), Irish Republican Army (IRA), Basque Fatherland and Freedom (ETA), Revolutionary Armed Forces of Colombia (FARC), Taliban, Liberation Tigers of Tamil Eelam, New Peoples Army, National Liberation Army of Colombia (ELN), and Kurdistan Workers Party (PKK). State sponsors
A state can sponsor terrorism by funding or harboring a terrorist group. Opinions as to which acts of violence by states consist of state-sponsored terrorism vary widely. When states provide funding for groups considered by some to be terrorist, they rarely acknowledge them as such. State terrorism
Civilization is based on a clearly defined and widely accepted yet often unarticulated hierarchy. Violence done by those higher on the hierarchy to those lower is nearly always invisible, that is, unnoticed. When it is noticed, it is fully rationalized. Violence done by those lower on the hierarchy to those higher is unthinkable, and when it does occur it is regarded with shock, horror, and the fetishization of the victims. As with "terrorism" the concept of "state terrorism" is controversial. The Chairman of the United Nations Counter-Terrorism Committee has stated that the committee was conscious of 12 international conventions on the subject, and none of them referred to state terrorism, which was not an international legal concept. If states abused their power, they should be judged against international conventions dealing with war crimes, international human rights law, and international humanitarian law.
When hepcidin binds ferroportin, ferroportin is phosphorylated, endocytosed, tagged with ubiquitin, and degraded. More than 39 mutations to the SLC40A1 gene have been identified in patients with type 4 hemochromatosis. The misregulation of ferroportin in type 4 hemochromatosis can involve a failure of ferroportin to be properly expressed at the cell membrane, or it can involve a failure of ferroportin to respond to negative regulation by hepcidin.Hemochromatosis type 4A is characterized by impaired iron export in cells. Reticuloendothelial macrophages are most affected. Iron accumulates preferentially in Kupffer cells, which are located in the liver, and serum ferritin increases; less iron is available for circulating transferrin, a protein that binds iron and transports it through the bloodstream to cell receptors. This means that, while iron is trapped in certain types of tissues, it cannot be transported to tissues where it is needed. The accumulation of iron in tissues due to impaired iron export can lead to increasing transferrin iron saturation and liver parenchymal iron overload in advanced stages of the disease. More ferritin is produced to suppress oxidative cell damage, although the amount of ferritin that cells can accumulate is limited.Hemochromatosis type 4B is characterized by abnormal iron release from macrophages and enterocytes because the mutant ferroportin is resistant to the hepcidin protein, which serves a regulatory function in wild-type ferroportin. Intestinal iron absorption and release of iron from macrophages is increased. Thus, this form of the disease leads to elevated transferrin saturation levels. Systemic iron overload results, and liver iron deposition is primarily in the hepatocytes.