Sunday, May 11, 2014

Functions of Specialized organs


FUNCTIONS OF SPECIALIZED ORGANS

Organ
Function
Blood vessels
Distribute blood to peripheral tissues and organs
Esophagus
Conveys food to stomach
Eye
Transduces light into electrical signals
Intestines
Absorbs digested food into blood and lymphatics
Liver
Metabolize or transform absorbed products and returns them to blood
Lymphatics
Recirculate extravascular fluid to cardiovascular system
Lymph nodes
Filters lymphatic fluid and initiates immune reaction to antigens
Mammary gland
Provides for release of milk protein
Pancreas
Elaborates digestive juice and controls carbohydrate metabolism
Reproductive system
Provides for release and movement of cells and embryo
Respiratory system
Collects and absorbs oxygen and releases carbondioxide
Spleen
Filters of blood particulates and dead cells, triggers immune response to blood-borne antigens
Stomach
Stores and digest food
Thymus
Serves as a supply of stem cells that differentiate into T cells
Urinary system
Filters waste products from blood.

*Courtesy: Biomaterials Science and Biocompatibility By Frederick H. Silver, David L. Christianse

Saturday, May 10, 2014

Bio-compatibility Matrix

What is bio-compatibility?
Bio-compatibility refers to the behaviour of the materials that are used in developing the device under various circumstances. It tells us about how a material behaves and responds in front of a host substance. The IUPAC defines it as "the ability of a material to perform with an appropriate host response in a specific application1. General definition would be “the ability to be in contact with a living system without producing an adverse effect2.” Biocompatibility is the ability of a material or device to remain biologically inactive during the implantation period4.

Hence all products that are used for human use need to have biocompatibility. This is specially required for all medical devices that enter into the human system in any part from any portion.

ISO 10993-1 provides details of the criteria that the medical devices should meet based upon their contact with the body and extent or duration of contact.




* P indicate data end points that can be necessary for a biological safety evaluation, based on a risk analysis. Where existing data is adequate, additional testing is not required.

For further information on biocompatibility requirements of medical devices please refer ISO 10993 set of standards.

References:
1.     Wikipedia
2.     Pure Appl. Chem., Vol. 84, No. 2, pp. 377–410, 2012.
3.     ISO 10993-1:2009; © ISO 2009
4.   Encyclopedia of Medical Devices and Instrumentation, 2nd Edition, Jon G Webster, Vol.1, page 8.