Ossified

The VN cartilage, the VN glands and the vasomotor network are all functionally necessary components without whose various contributions the receptor cells would be unlikely to function. These ancillary constituents show a parallel developmental sequence. The cartilage may become partly ossified and incompletely surrounds the organ, the enclosure lessening towards the posterior end. In the mature organ, maximum enclosure is usually found along the sensory section. 

Ossified means to make rigid and hard. The word comes from the Latin ossis, meaning bone. 

Limestone is an ossified form of calcium carbonate, CaCC>3. Limestone surfaces soon become slippery and can be quite dangerous if... 

Developmental Toxicity. No studies were located regarding developmental effects in humans after inhalation, oral, or dermal exposure to disulfoton or in animals after inhalation or dermal exposure. Developmental effects have been found in animals after acute- and intermediate-duration oral exposure to disulfoton. Plasma and erythrocyte cholinesterase depression and increased incidences of incomplete ossified parietal bones and sternebrae were observed in fetuses from rats fed... 

For rodents, one-half of the fetuses are submitted to a fixed soft tissue examination and half are submitted to skeletal examination (see Note 5). The ossified skeleton of the remaining rodent fetuses is stained with alizarin red (see Chapter 16). Additional staining of the cartilage with alcian blue (see Chapter 17) is optional. Allocation of the fetuses within each litter to soft tissue or skeletal examination is performed alternately or randomly. 

Approximately one half of the fetuses in each litter (i.e., every alternate fetus in the uterus) are eviscerated and fixed for skeletal examination. The skeletal examination is performed following maceration of the soft tissue with aqueous potassium hydroxide and staining of the skeleton. Single staining, of the ossified bones only, is performed for pharmaceuticals (see Chapter 16) and double staining, of the bone and cartilage is performed for chemicals (see Chapter 17). 

Certain guidelines (5-7) require or give as an option a double staining method for the fetal skeleton with Alcian Blue added to stain cartilage together with Alizarin for the ossified material. 

Staining with alizarin red for 18-24 h Ossified bones are stained red to purple, cartilage is stained light pink. 

Skeletal Examination by Double Staining for Ossified Bone and Cartilaginous Tissue... 

Prenatal developmental toxicity testing of chemicals and pesticides requires evaluation of both cartilaginous and ossified skeletal components, but the corresponding testing guidelines do not specify how. Double staining is the preferred method and is strongly recommended. 

In a double-stained skeleton the ossified bone will be stained red to purple and the cartilage blue (Figs. 1, 2, and 3). The staining of the cartilage allows the examiner to assess whether the underlying structure of a non-ossified bone is present and how it is shaped. The ratio of blue to red structures enables the investigator to discern accelerated or retarded ossification at a glance. 

Jibril, A, O. Proteolytic degradation of ossifying cartilage matrix and the removal of acid mucopolysaccharides prior to bone formation. Biochim. Biophys. Acta 136, 162 (1967)... 

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