Insulin oscillation oscillations. The insulin oscillations are generated by pulsatile release of the hormone from the pancreas. Insulin originates from beta cells located in the islets of Langerhans. Since each islet contains up to 2000 beta cells and there are one million islets in the pancreas it is apparent that pulsatile secretion requires sophisticated synchronization both within and among the islets of Langerhans. Pulsatile insulin secretion from individual beta cells is driven by oscillation of the calcium concentration in the cells. In beta cells lacking contact, the periodicity of these oscillations is rather variable (2-10 min). However, within an islet of Langerhans
Langerhans cell defense mechanism, destroying incoming viruses." High-risk human papillomaviruses (HPV) are sexually transmitted viruses causally associated with several cancers including cervical, vaginal, anal, and head and neck cancers that cause significant morbidity and mortality worldwide. Over half of all cervical cancer cases are associated with HPV16, the most common of the cancer-causing high-risk genotypes. During its natural life cycle, HPV16 infects the basal cells of the epithelium and interacts with Langerhans cells within the epithelial layer, which are responsible for initiating immune responses against epithelial invading pathogens. However, HPV does not activate Langerhans cells "in vitro", and this may represent a