Nasal cavity

Jiroma. The fragrance or odor of food, perceived by the nose by sniffing. In wines, the aroma refers to odors derived from the variety of grape, eg, muscat aroma. It is the overall odor impression as perceived by the nasal cavity. 

Odor and Odorant. That which is smelled. Odor may refer to the odorant or to the sensation resulting from the stimulation of olfactory receptors in the nasal cavity by gaseous material. 

Odors are perceived via the olfactory system, which is composed of two organs in the nose the olfactory epithelium, a very small area in the nasal system, and the trigeminal nerve endings, which are much more widely distributed in the nasal cavity (11). The olfactory epithelium is extremely sensitive, and humans often sniff to bring more odorant in contact with this area. The trigeminal nerves initiate protective reflexes, such as sneezing or interruption of irrhalation, with exposure to noxious odorants. 

Meatus An opening or passage .. . of the nasal cavity air passages between... 

Nares Orifices leading into the nasal cavity nostrils. 

Nasal cavity Airway passages between the nares and posterior termination of the nasal septum. 

Nasal turbinates Region within the nasal cavity denoted by convoluted... 

The epithelium covering the nasal cavity. This epithelium contains numerous cell types including the specialized olfactory sensory neurons which detect the chemical stimuli derived from smells by a specific family of G protein-coupled receptors known as olfactory receptors. 

Desmopressin may be given orally, intranasally, SC, or IV. The oral dose must be determined for each individual patient and adjusted according to the patient s response to therapy. When the drug is administered nasally, a nasal tube is used for administration. The nasal tube delivery system comes with a flexible calibrated plastic tube called a rhinyle. The solution is drawn into the rhinyle. One end is inserted into the nostril and the patient (if condition allows) blows the other end to deposit solution deep into the nasal cavity. A nasal spray pump may also be used. Most adults require 0.2 mL daily in two divided doses to control diabetes insipidus. The drug may also be administered via the SC route or direct IV injection. 

The prescribed amount of solution is drawn into the rhinyle. One end is inserted into the nostril, and the patient blows the other end to deposit solution deep into the nasal cavity. 

These studies on NPYR are typical of the state of the art in cyclic nitrosamine metabolism ai d activation. The major metabolic pathways have been rather well characterized, but data on the relationship of these pathways to carcinogenesis are limited. This is especially true of the organospecific effects of NPYR and the other cyclic nitrosamines. For example, the main target organs for NPYR in the Syrian golden hamster are the trachea and nasal cavity rather than the liver. This is in spite... 

NNN is formally a derivative of NPYR, but the pyridine ring has a marked effect on its metabolism and carcinogenicity. NNN induces lung adenomas in mice, esophageal and nasal cavity tumors... 

NPIP induces esophageal and nasal cavity tumors in the rat, forestomach, liver and lung tumors in the mouse, and tracheal tumors in the Syrian golden hamster (43, 44, 45). Its potent carcinogenicity is indicated by the fact that a single dose of only 22 mg/kg was sufficient to induce tumors in 20% of Syrian golden hamsters (45). The environmental occurrence of NPIP appears to be less frequent than that of NPYR, but it has been detected in food (J, 44). 

NMOR is a potent hepatocarcinogen in the rat and induces tracheal and nasal cavity tumors in the Syrian golden hamster (43, 44, 45). It is formed readily from nitrite and morpholine in vitro and administration of these precursors to rodents causes tumors indicative of NMOR formation in vivo (44, 55, 56), NMOR has been detected in crankcase emissions of diesel engines and in factories engaged in rubber and tire manufacturing (57, 58). 

Carcinogenicity of NDELA. Our special interest in NDELA as a constituent of tobacco products and as an environmental agent relates to the observation that this nitrosamine induces carcinoma of the liver as well as of the kidney in rats (21,22) and carcinoma of the nasal cavity and papillomas of the trachea in hamsters (23). Recently, Lijinsky reported that NDELA admini-... 

Hamster s.c. Trachea (Papilloma) Nasal Cavity (Carcinoma) 23,45... 

Rat s.c. Nasal Cavity (Carcinoma) Liver Lung (Adenoma, Carcinoma) 44... 

Fig. 2.3(b) Relations of palate to oral and nasal cavities in A. Amphibia B. Reptiles and C. Mammals, a — p limits of internal nostril, ch = choana, fp = false palate, nc = nasal cavity, npc = naso-palatine canal, and pr = palatine ridge (from Goodrich, 1930 after Seydel, 1899). 

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