Search results for "Hair shaft"
showing 5 items of 5 documents
Fine structure of sensilla during moulting inNeomysis integer (Leach) (Crustacea, Mysidacea)
1980
During the moulting cycle the sensory cells and the newly formed hair shaft remain connected to the old cuticular receptive apparatus of the sensillum by the elongated outer segments of the dendrites, which run through the exuvial space. A surface coat covering the outer dendritic segments protects them against the chemical influences of the exuvial fluid. The findings suggest that the receptors remain functional until ecdysis. This moulting type is considered to be a transitional form between the moulting types so far known.
Cricket combined mechanoreceptors and kicking response
1977
1. Only those filiform hairs on the cerci ofGryllus, which are coupled with campaniform sensilla, show a) a thickening of the hair shaft at the height of the upper ring lamella of their sockets and b) a thin cuticular membrane, which surrounds their sockets. While thefiliform hairs themselves are deflected either parallel to the long axis of the cerci or perpendicular to it, thesockets of the filiform hairs may be deflected preferentially in the proximal and distal direction. 2. Spike potentials can be recorded from the sensory cells of the filiform hairs as long as these are deflected in a weak air current, but not during permanent deflection in strong air streams when they touch the inner…
Contribution to the Knowledge of Dermatophytic Invasion of Hair
1970
We have used the scanning electron microscope to investigate the changes that occur in scalp hair during infection with Trichophyton violaceum . We provide information on the morphology of these dermatophytes and present evidence that their hyphae dig tunnel-like burrows into the hair shaft, dissociating hair into keratin fibrils.
Development of antennal sensilla during moulting inNeomysis integer (Leach) (Crustacea, Mysidacea)
1980
The sensilla are associated with 6 enveloping cells. The innermost enveloping cell (e 1) secretes the dendritic sheath (=thecogen cell). All other enveloping cells are involved in the formation of the outer cuticular apparatus in secreting the cuticle of a definite region of the new hair shaft. The development of the new sensilla begins when an exuvial space expands between old cuticle and epithelium. The newly forming hair shafts lie folded back in an invagination of the epidermal tissue. Only a distal shaft part projects into the free exuvial space. The cuticle of the distal and middle shaft region is secreted by the three middle enveloping cells (e 2–e 4) (=trichogen cells), which are ar…
Pili Torti: A Feature of Numerous Congenital and Acquired Conditions
2021
Pili torti is a rare condition characterized by the presence of the hair shaft, which is flattened at irregular intervals and twisted 180° along its long axis. It is a form of hair shaft disorder with increased fragility. The condition is classified into inherited and acquired. Inherited forms may be either isolated or associated with numerous genetic diseases or syndromes (e.g., Menkes disease, Björnstad syndrome, Netherton syndrome, and Bazex-Dupré-Christol syndrome). Moreover, pili torti may be a feature of various ectodermal dysplasias (such as Rapp-Hodgkin syndrome and Ankyloblepharon-ectodermal defects-cleft lip/palate syndrome). Acquired pili torti was described in numerous forms of …