Clinically important antiphospholipid antibodies (those that arise as a result of the autoimmune process) are associated with thrombosis and vascular disease. The syndrome can be divided into primary (no underlying disease state) and secondary (in association with an underlying disease state) forms.Anti-ApoH and a subset of anti-cardiolipin antibodies bind to ApoH. ApoH inhibits protein C, a glycoprotein with important regulatory function of coagulation (inactivates Factor Va and Factor VIIIa). Lupus anticoagulant antibodies bind to prothrombin, thus increasing its cleavage to thrombin, its active form.In APS there are also antibodies binding to protein S, which is a co-factor of protein C. Thus, anti-protein S antibodies decrease protein C efficiency.Annexin A5 forms a shield around negatively charged phospholipid molecules, thus reducing their availability for coagulation. Thus, anti-annexin A5 antibodies increase phospholipid-dependent coagulation steps.The lupus anticoagulant antibodies are those that show the closest association with thrombosis; those that target β2glycoprotein 1 have a greater association with thrombosis than those that target prothrombin. Anticardiolipin antibodies are associated with thrombosis at moderate to high titres (over 40 GPLU or MPLU). Patients with both lupus anticoagulant antibodies and moderate or high titre anticardiolipin antibodies show a greater risk of thrombosis than with one alone.The increased risks of recurrent miscarriage, intrauterine growth restriction and preterm birth by antiphospholipid antibodies, as supported by in vitro studies, include decreased trophoblast viability, syncytialization and invasion, deranged production of hormones and signalling molecules by trophoblasts, as well as activation of coagulation and complement pathways.
Gastric cancer, though present, is relatively low when compared to countries with high incidence like Japan and China. One suspected cause of the variation within Africa and between other countries is due to different strains of the H. pylori bacteria. The trend commonly seen is that H. pylori infection increases the risk for gastric cancer, but this is not the case in Africa, giving this phenomenon the name the "African enigma". Although this bacterial species is found in Africa, evidence has supported that different strains with mutations in the bacterial genotype may contribute to the difference in cancer development between African countries and others outside the continent. Increasing access to health care and treatment measures have been commonly associated with the rising incidence, though, particularly in Uganda. Other animals
The stomach is a muscular organ of the gastrointestinal tract that holds food and begins the digestive process by secreting gastric juice. The most common cancers of the stomach are adenocarcinomas, but other histological types have been reported. Signs vary, but may include vomiting (especially if blood is present), weight loss, anemia, and lack of appetite. Bowel movements may be dark and tarry in nature. To determine whether cancer is present in the stomach, special X-rays and/or abdominal ultrasounds may be performed. Gastroscopy, a test using an endoscope to examine the stomach, is a useful diagnostic tool that can also take samples of the suspected mass for histopathological analysis to confirm or rule out cancer. The most definitive method of cancer diagnosis is through open surgical biopsy.