Search results for "Factory system"
showing 10 items of 94 documents
Acute effects of 1,1,1-trichloroethane on human olfactory functioning.
2004
Background Animal experiments indicate that 1,1,1-trichloroethane can cause degeneration of the olfactory epithelium. The effects of 1,1,1-trichloroethane on human odor perception still have not been investigated. The goal of this study was to learn more about acute effects of 1,1,1-trichloroethane. Methods Twelve healthy, nonsmoking students were exposed to 200 and 20 ppm (control) 1,1,1-trichloroethane in an exposure chamber for 4 hours according to a crossover design. Olfactory functioning was investigated with the Sniffin’ Sticks. The test includes the determination of the detection threshold for n-butanol and an odor identification test. Results After 1 hour of exposure to 200 ppm 1,1,…
Olfactory function after microscopic endonasal surgery in patients with nasal polyps.
1997
A controlled prospective study on 31 patients with nasal polyps was performed to evaluate the time course of olfactory function after endonasal surgery. A modified Connecticut Chemosensory Clinical Research Center (CCCRC) olfactory function test was used to measure olfactory threshold, odor identification ability, and odor discrimination ability. The test was performed in all patients 1–3 days before surgery (V1), 7–10 days after surgery (V2), and after 1 (V3), 2 (V4), 3 (V5), and 6 (V6) months. Mean olfactory threshold in the CCCRC butanol test was 4.19 at V1 (= moderate hyposmia). At V2, it decreased to 3.46 (= severe hyposmia), before increasing to 5.16 at V3 and 5.22 at V4 (= mild hypo…
Afferent and efferent connections of the olfactory bulbs in the lizard Podarcis hispanica.
1991
The connections of the olfactory bulbs of Podarcis hispanica were studied by tract-tracing of injected horseradish peroxidase. Restricted injections into the main olfactory bulb (MOB) resulted in bilateral terminallike labeling in the medial part of the anterior olfactory nucleus (AON) and in the rostral septum, lateral cortex, nucleus of the lateral olfactory tract, and ventrolateral amygdaloid nucleus. Bilateral retrograde labeling was found in the rostral lateral cortex and in the medial and dorsolateral AON. Ipsilaterally the dorsal cortex, nucleus of the diagonal band, lateral preoptic area, and dorsolateral amygdala showed labeled cell bodies. Retrogradely labeled cells were also foun…
Expression of Odorant Receptor Family, Type 2 OR in the Aquatic Olfactory Cavity of Amphibian Frog Xenopus tropicalis
2012
International audience; Recent genome wide in silico analyses discovered a new family (type 2 or family H) of odorant receptors (ORs) in teleost fish and frogs. However, since there is no evidence of the expression of these novel OR genes in olfactory sensory neurons (OSN), it remains unknown if type 2 ORs (OR2) function as odorant receptors. In this study, we examined expression of OR2 genes in the frog Xenopus tropicalis. The overall gene expression pattern is highly complex and differs depending on the gene and developmental stage. RT-PCR analysis in larvae showed that all of the OR2η genes we identified were expressed in the peripheral olfactory system and some were detected in the brai…
Fine Structure of Antennal Sensilla of Paysandisia archon and Electrophysiological Responses to Volatile Compounds Associated with Host Palms
2014
Paysandisia archon (Lepidoptera: Castniidae) is a serious pest of palm trees. A comprehensive knowledge of the insect olfactory system is essential for the development of efficient semiochemical-based control methods. The olfactory sensilla are located particularly on the antennae, and these can detect plant volatiles that provide important cues for the insects in the search for their host plants. To date, the fine structure of P. archon antennal sensilla studies and their role in host-plant perception have not been investigated in great detail. Using light microscopy and scanning and transmission electron microscopy, the antennae of both sexes of P. archon are described here in detail, acc…
Characterization of somatostatin- and cholecystokinin-immunoreactive periglomerular cells in the rat olfactory bulb.
2005
Periglomerular cells (PG) are interneurons of the olfactory bulb (OB) that modulate the first synaptic relay of the olfactory information from the olfactory nerve to the dendrites of the bulbar principal cells. Previous investigations have pointed to the heterogeneity of these interneurons and have demonstrated the presence of two different types of PG. In the rat OB, type 1 PG receive synaptic contacts from the olfactory axons and are γ-aminobutyric acid (GABA)-ergic, whereas type 2 PG do not receive synaptic contacts from the olfactory axons and are GABA immunonegative. In this study, we analyze and characterize neurochemically a group of PG that has not been previously classified either …
Forebrain specialization and the olfactory system in anseriform birds. An architectonic and tracing study.
1992
In anseriform birds the mediodorsal part of the rostral forebrain is covered by a corticoid (= layered) structure, establishing a unique feature of this avian group since in other birds the non-cortical accessory or dorsal hyperstriatum occupies the corresponding surface area of the hemisphere. The efferents of the olfactory bulb are shown to reach this region, which thus can be identified as a heavily enlarged retrobulbar area. The large expansion of this olfactory representation may indicate an important biological function. In comparison to the mammalian olfactory system the three stratified olfactory projection centers of birds should be regarded as retrobulbar, prepiriform and periamyg…
Exotic Models May Offer Unique Opportunities to Decipher Specific Scientific Question: The Case ofXenopusOlfactory System
2013
The fact that olfactory systems are highly conserved in all animal species from insects to mammals allow the generalization of findings from one species to another. Most of our knowledge about the anatomy and physiology of the olfactory system comes from data obtained in a very limited number of biological models such as rodents, Zebrafish, Drosophila, and a worm, Caenorhabditis elegans. These models have proved useful to answer most questions in the field of olfaction, and thus concentrating on these few models appear to be a pragmatic strategy. However, the diversity of the organization and physiology of the olfactory system amongst phyla appear to be greater than generally assumed and th…
Neural substrates for processing chemosensory information in snakes.
2002
Snakes interact with their chemical environment through their olfactory and vomeronasal systems. The present report summarizes advances on neural substrates for processing chemosensory information. First, the efferent and centrifugal afferent connections of the main and accessory olfactory bulbs were reinvestigated. Second, the afferent and efferent connections of the nucleus sphericus, the main target of the accessory olfactory bulb, were characterized. The nucleus sphericus gives rise to a very small projection to the hypothalamus, but it does project to other telencephalic structures where olfactory and vomeronasal information could converge. Third, the intra-amygdaloid circuitry and the…
UDP-glucuronosyltransferases (UGTs) in neuro-olfactory tissues: expression, regulation, and function.
2010
International audience; This work aims to review uridine diphosphate (UDP)-glucuronosyltransferase (UGT) expression and activities along different neuronal structures involved in the common physiological process of olfaction: olfactory epithelium, olfactory bulb, and olfactory cortex. For the first time, using high-throughput in situ hybridization data generated by the Allen Brain Atlas (ABA), we present quantitative analysis of spatial distribution of UGT genes in the mouse brain. The olfactory area is a central nervous system site with the highest expression of UGTs, including UGT isoforms not previously identified in the brain. Since there is evidence of the transfer of xenobiotics to th…