Trypanosomiasis refers to a group of diseases caused by Trypanosoma There are two types of trypanosomiasis that affect humans, they are divided according to their geographical location: African trypanosomiasis, or sleeping sickness, is caused by Trypanosoma brucei parasites in sub-Saharan Africa and is transmitted by the tsetse fly? (Glossina).
Specilized cells in the epidermis called melanocytes produce melanin, a dark pigment that provides skin color. Melanin absorbs ultraviolet radiation in sunlight and preventing mutations in the DNA of skin cells and other damaging effects.ifferences in skin color result from differences in the amount of melanin that melanocytes produce and the distribution and size of pigment granules. Skin color is genetically determined.
Melanocytes are the cells that synthesize pigment. Through a series of enzymatic reactions these cells efficiently produce melanin pigment that determines skin color. Once it is formed, melanin is packaged into tiny vesicles called melanosomes. The melanocyte has tiny tentacles that it uses to transfer melanosomes to other skin cells. It is interesting to note that dark-skinned patients do not have more melanocytes but instead have melanocytes with more pigment producing power.