Past infections (Chlamydia pneumoniae, Helicobacter pylori, cytomegalovirus, and herpes simplex virus 1 and 2) may contribute to vascular risks and cognitive impairment (brain, behavior and computation)
Objective: We hypothesized that infectious burden (IB), a composite serologic measure of exposure to common pathogens (i.e., Chlamydia pneumoniae, Helicobacter pylori, cytomegalovirus, and herpes simplex virus 1 and 2) associated with vascular risk in the prospective Northern Manhattan Study (NOMAS), would also be associated with cognition.
Methods: Cognition was assessed using the Mini-Mental State Examination (MMSE) at enrollment and the modified Telephone Interview for Cognitive Status (TICS-m) at annual follow-up visits. Adjusted linear and logistic regressions were used to measure the association between IB index and MMSE. Generalized estimating equation models were used to evaluate associations with TICS-m and its change over time.
Conclusion: A measure of IB associated with stroke risk and atherosclerosis was independently associated with cognitive performance in this multiethnic cohort. Past infections may contribute to cognitive impairment.
Reference: Neurology March 26, 2013 vol. 80 no. 13 1209-1215

Transportation of the substances necessary to maintain cellular metabolism is one of two main functions of the circulatory system. In conjunction with the respiratory system, red blood cells by the name of erythrocytes are responsible for the transportation of oxygen which are systematically delivered to the cells waiting throughout the body. The human body takes a breath, which enters the lungs. In the lungs, the oxygen molecules attach themselves to hemoglobin molecules, which reside within the erythrocytes, and then make their way via transport by these cells to cells in need of oxygen. Once the cells have used the oxygen which has been delivered, the carbon dioxide that they have produced are then transported back to the lungs and expelled in exhaled air.

The blood and lymph vessels work in conjunction with the digestive system in order for the circulatory system to perform the delivery of nutrition. When food is eaten it is broken down by the digestive system and the nutrients are absorbed through the wall of the intestines, which is then picked up by the blood vessels and carried off to the cells requiring the nutrition with a pit stop through the liver for nutrient absorption and toxic cleansing.

The wastes associated with excess waters, ions, plasma, and metabolic waste produced by the cells which were delivered their nutrients, are then filtered through capillaries which belong to the kidneys. From there wastes enter the kidney tubes and are excreted in urine.

The circulatory system is also responsible for the transportation of hormones through the blood stream. This contributes to the regulatory process of maintaining health of the endocrine system.

The second basic function associated with the circulatory system involves protection. It effectively protects against both injury and disease through clotting, white blood cells, and the process of phagocytosis. White blood cells called leukocytes fight off disease and foreign material in the body. The body becomes feverish in this action as it works harder to produce a greater number of leukocytes.

The body’s natural ability to clot prevents excessive bleeding when blood vessels are harmed or damaged. Excessive damage may cause bleeding faster than the body can create clotting agents, but in most cases the clotting agents cease bleeding for long periods of time.