• BMB Reports
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• 제54권6호
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• pp.295-304
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• 2021

Olfactory neuropathology is a cause of olfactory loss in Alzheimer's disease (AD). Olfactory dysfunction is also associated with memory and cognitive dysfunction and is an incidental finding of AD dementia. Here we review neuropathological research on the olfactory system in AD, considering both structural and functional evidence. Experimental and clinical findings identify olfactory dysfunction as an early indicator of AD. In keeping with this, amyloid-β production and neuroinflammation are related to underlying causes of impaired olfaction. Notably, physiological features of the spatial map in the olfactory system suggest the evidence of ongoing neurodegeneration. Our aim in this review is to examine olfactory pathology findings essential to identifying mechanisms of olfactory dysfunction in the development of AD in hopes of supporting investigations leading towards revealing potential diagnostic methods and causes of early pathogenesis in the olfactory system.

• Animal cells and systems
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• 제3권3호
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• pp.259-267
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• 1999

The expression of the neural cell adhesion molecule-180 (NCAM-180), which accumulates at contact sites between cells and may be responsible for the stabilization of cell contacts, was studied in the olfactory system and retina of developing and adult rats. From embryonic day 12 onwards, which was the earliest stage examined, the NCAM-180 pathway directing to the presumptive olfactory bulb was observed. In later stages, olfactory neurons and fasciculating axons in the olfactory epithelium and nerve fiber layer and glomeruli of the olfactory bulb expressed NCAM-180. From postnatal day 0, immunolabelling pattern of the olfactory epithelium and olfactory bulb were the same as that during later stages. NCAM-180 immunoreactivity was present on differentiating retinal cells and persisted on those cells throughout adulthood. However, contrary to the olfactory nerve which remained detectable in the adult, the optic nerve was only transiently expressed with NCAM-180 and was no longer detectable in the adult. The presence of NCAM-180 in olfactory tissues suggests their possible role in pathfinding, differentiation, fasciculation and synaptic plasticity. The continued presence of NCAM-180 in the olfactory system examined may underlie its continuous cell turnover and regenerative capacity. The continuous expression of NCAM-180 in ganglion cells, bipolar cells and photoreceptor cells, also suggests potential regenerating capability and some plastic functions for these cells in the adult. Since the expression of NCAM-180 by the optic nerve was restricted to the period of special histogenetic events, for example, during axonal growth and synaptogenesis, it is possible that the lack of NCAM-180 in the adult optic nerve might cause a nonpermissive environment for the regeneration and result in regenerative failure of this system.

• Genomics & Informatics
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• 제16권1호
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• pp.2-9
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• 2018

Olfactory receptors (ORs) in mammals are generally considered to function as chemosensors in the olfactory organs of animals. They are membrane proteins that traverse the cytoplasmic membrane seven times and work generally by coupling to heterotrimeric G protein. The OR is a G protein-coupled receptor that binds the guanine nucleotide-binding $G{\alpha}_{olf}$ subunit and the $G{\beta}{\gamma}$ dimer to recognize a wide spectrum of organic compounds in accordance with its cognate ligand. Mammalian ORs were originally identified from the olfactory epithelium of rat. However, it has been recently reported that the expression of ORs is not limited to the olfactory organ. In recent decades, they have been found to be expressed in diverse organs or tissues and even tumors in mammals. In this review, the expression and expected function of olfactory receptors that exist throughout an organism's system are discussed.

• Journal of Korean Neurosurgical Society
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• 제29권12호
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• pp.1570-1576
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• 2000

Objective : To evaluate objectively the sites of injury in patients with posttraumatic olfactory deficits and to suggest the diagnostic procedure for evaluation of posttraumatic anosmia. Methods : Ten patients with posttraumatic olfactory dysfunction were examined by means of olfactory testing, sinoscopy, contrast filled paranasal sinus computed tomography(contrast filled PNS CT) and magnetic resonance imaging(MRI). Five normal persons without olfactory dysfunction were also evauluated. The aerodynamic patency of olfactory cleft was examined by contrast filled PNS CT. The olfactory system(oflactory bulbs, olfactory tracts, inferior frontal region, hippocampi, or temporal lobes) was investigated in detail with MRI. The difference in the size of the olfactory bulb between normal volunteers and anosmic patients was evaluated by Student's t test. Results : Contrast filled dynamic CT scan was useful method for the evaluation of dynamic patency of the olfactory cleft. Paranasal CT scan of the all anosmic patients showed dynamic reflux of contrast media in olfactory cleft on valsalva maneuver. For the largest cross-sectional area and great height, the difference in olfactory bulb size between normal volunteers and patients was statistically significant(p<0.001) in MRI study. Conclusion : Posttraumatic anosmia was completely evaluated by olfactory testing, sinoscopy, and contrast filled CT scan for differentiation between conductive type and neurogenic type. Neurogenic anosmia was confirmed by perfect localization with MRI study.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1312-1315
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• 2009

An olfactory display is a device that delivers smells to the nose. It provides us with special effects, for example to emit smell as if you were there or to give a trigger for reminding us of memories. The authors have developed a tabletop display system connected with the olfactory display.

• KSBB Journal
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• 제13권6호
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• pp.631-637
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• 1998

후각은 가장 민감한 감각 기관으로 다른 감각에 비해 아직 많은 연구가 이루어져 있지 않다. 후각의 이론적 접근은 100년도 안되는 역사를 가지고 있고, 후각세포에서 일어나는 전기적 신호를 측정한 것은 50년 전의 일이었다. 최근들어 후각의 산업적 응용에 대한 관심으로 인해 많은 연구가 진행중이다. 본 고에서는 후각의 신호 전달 과정을 이해하기 위해 포유 동물과 곤충의 후각 기관의 구조를 비교하고 각각의 인지 과정을 분자 수준에서 살펴보았다. 또한 후각 기관의 냄새 인지 과정을 이해하여 후각 센서로의 이용 가능성에 대해 검토하고, 현재 후각 센서의 개발 현황을 알아보았다. 후각에 대한 연구는 앞으로 센서산업에 많은 기여를 할 것으로 기대된다.

• 센서학회지
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• 제30권4호
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• pp.204-209
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• 2021

Immersive multimedia comprising metadata for five senses can provide user experience by stimulating memory and sensation. In the case of olfactory-enhanced multimedia, a computer-generated smell is combined with additional media content to create a richer and/or more realistic experience for the user. Although several studies have been conducted on olfactory-enhanced multimedia using e-nose and olfactory display, their practical applications have been severely restricted owing to the absence of a related standard. This paper proposes a method to standardize odor metadata obtained from an e-nose system, which has been particularly used to acquire data from different coffee aromas. Subsequently, the data were transferred to an odor display applicable for olfactory-enhanced multimedia using the ISO/IEC 23005 (MPEG-V) data template.

• BMB Reports
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• 제45권11호
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• pp.612-622
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• 2012

Olfactory receptors (ORs) detect volatile chemicals that lead to the initial perception of smell in the brain. The olfactory receptor (OR) is the first protein that recognizes odorants in the olfactory signal pathway and it is present in over 1,000 genes in mice. It is also the largest member of the G protein-coupled receptors (GPCRs). Most ORs are extensively expressed in the nasal olfactory epithelium where they perform the appropriate physiological functions that fit their location. However, recent whole-genome sequencing shows that ORs have been found outside of the olfactory system, suggesting that ORs may play an important role in the ectopic expression of non-chemosensory tissues. The ectopic expressions of ORs and their physiological functions have attracted more attention recently since MOR23 and testicular hOR17-4 have been found to be involved in skeletal muscle development, regeneration, and human sperm chemotaxis, respectively. When identifying additional expression profiles and functions of ORs in non-olfactory tissues, there are limitations posed by the small number of antibodies available for similar OR genes. This review presents the results of a research series that identifies ectopic expressions and functions of ORs in non-chemosensory tissues to provide insight into future research directions.

• 한국융합학회논문지
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• 제7권2호
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• pp.61-67
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• 2016

후각기관은 주변 환경의 다양한 화학물질을 감지하는 기관으로 생존, 종족번식에서 감정에 이르기까지 다양하고 중요한 역할을 하고 있다. 유전적, 환경적 등 다양한 요소에 의해 후각장애가 발생할 수 있으며, 일시적인 경우에는 약물치료 등으로 회복될 수 있지만, 신경세포에 문제가 생긴 영구적인 손상의 경우는 치료가 어렵다. 따라서, 신경세포의 사멸을 억제하거나 재생을 유도하는 치료제의 개발이 필요하다. 본 연구에서는 후각신경세포 특이적으로 GFP 형광단백질을 발현하는 형질전환동물을 제작하여 생체 내 후각신경세포를 관찰하고자 하였다. 또한, 다양한 화학물질을 처리하여 후각신경세포 손상을 인위적으로 유도할 수 있는 방법을 고안하였고, 후각신경세포의 손상 및 재생 과정을 실시간으로 모니터링하였다. 본 연구를 통해 확립된 후각신경세포의 손상 및 재생 모니터링 시스템은 향후 후각신경세포 재생 메커니즘 연구 및 치료제 개발에 유용하게 사용될 것으로 기대된다.

• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.928-933
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• 2007

Cameleon is a genetically engineered $Ca^{2+}$ sensing molecule consisting of two variants of the green fluorescent protein (GFP), calmodulin and calmodulin-binding protein, M13. HEK-293 cells stably expressing three types of cameleons, yellow cameleon-2, cameleon-3er, and cameleon-2nu, were constructed, and the expression and localization of these cameleons were confirmed by fluorescent imaging. Among the cameleons, the yellow cameleon-2 was selected for analyzing the change in $Ca^{2+}$ induced by the olfactory receptor-mediated signal transduction, because it is localized in the cytosol and binds to cytosolic $Ca^{2+}$ ions. Cells stably expressing yellow cameleon-2 were transfected with each of the test olfactory receptor genes, odr-10 and 17, and the expression of the olfactory receptor genes were examined using immunocytochenmical methods and RT-PCR. Stimulating each olfactory receptor with its specific odorant caused an increase in the intracellular $Ca^{2+}$ level, which was measured using yellow cameleon-2. These results demonstrate that yellow cameleon-2 can be conveniently used to examine the function of the olfactory receptors expressed in heterologous cells.