Odor Test Research Articles

Studying the Effects of Inhaled Environmental Pollutants on Olfactory Function in Mice.

Olfactory impairment is a significant public health problem and independently predicts the risk of neurodegenerative diseases. Inhaled environmental pollutants exposure may impair olfaction; thereby, there is an urgent need for methods to evaluate the effects of inhaled environmental pollutants exposure on olfaction. Mice are ideal models for olfactory experiments because of their highly developed olfactory system and behavioral characteristics. To assess the effects of inhaled environmental pollutants exposure on olfactory function in mice, a detailed buried food test and social odor discrimination experiment is provided, including the experiment preparation, the selection and construction of experimental facilities, the testing process, and indexes of time. Meanwhile, timekeeping equipment, operational details, and the experimental environment are discussed to ensure the success of the assay. Zinc sulfate is used as the treatment to demonstrate the feasibility of the experimental approach. The protocol provides a simple and clear operational process for assessing the effects of inhaled environmental pollutants on olfactory function in mice.

The odour of an unfamiliar stressed or relaxed person affects dogs’ responses to a cognitive bias test

Dogs can discriminate stressed from non-stressed human odour samples, but the effect on their cognition is unstudied. Using a cognitive bias task, we tested how human odours affect dogs’ likelihood of approaching a food bowl placed at three ambiguous locations (“near-positive”, “middle” and “near-negative”) between trained “positive” (rewarded) and “negative” (unrewarded) locations. Using odour samples collected from three unfamiliar volunteers during stressful and relaxing activities, we tested eighteen dogs under three conditions: no odour, stress odour and relaxed odour, with the order of test odours counterbalanced across dogs. When exposed to stress odour during session three, dogs were significantly less likely to approach a bowl placed at one of the three ambiguous locations (near-negative) compared to no odour, indicating possible risk-reduction behaviours in response to the smell of human stress. Dogs’ learning of trained positive and negative locations improved with repeated testing and was significant between sessions two and three only when exposed to stress odour during session three, suggesting odour influenced learning. This is the first study to show that without visual or auditory cues, olfactory cues of human stress may affect dogs’ cognition and learning, which, if true, could have important consequences for dog welfare and working performance.

Exploring the role of environmental enrichment and early life adversity on emotional development

Early life adversity has been linked with a higher probability of developing behavioral impairments and environmental manipulation is a strategy that may reduce the negative effects of exposure to adversity in early life. Here, we focused on exploring the influence of environmental enrichment (EE) as a protective factor in the context of early life adversity. We hypothesized that 24 hours of maternal deprivation (MD), in the second week of life, could induce anxiety-like behavior alterations and that exposure to EE could induce resilience to these behaviors due to alterations in the serotonergic system. Male Wistar rats were exposed to MD, on postnatal days 11 and 13, and to EE, after weaning. In adulthood, we performed a series of behavioral tests for fear, anxiety, and locomotor activity. We also measured the levels of serotonin in the amygdala and dorsal raphe nucleus. Our results revealed that MD does not impact fear behavior or the levels of serotonin, while EE decreases locomotor activity in a novel environment and enhances exploration in the predator odor test. EE also decreases serotonin in the amygdala and increases its turnover rate levels. Our findings provide insights into the critical timeframe during which stress exposure impacts the development and confirm that exposure to EE has an independent and protective effect for anxiety-like behaviors later in life.

Effect of endoscopic endonasal skull base approaches on olfactory function and facial development in children.

Endoscopic approaches for skull base pathologies are increasingly being performed, and the subsequent complications, especially in the long term, have also been partially clarified. However, there is no information on the effects of endoscopic endonasal skull base surgeries (EESBS) in children on odor and facial development in parallel with long-term development. We conducted this study to investigate postoperative olfactory function and facial development in pediatric patients who underwent skull base surgery using the endoscopic endonasal method. We evaluated the smell test, sinonasal symptoms, and facial development of pediatric patients who underwent endoscopic endonasal skull base surgery after long-term follow-up. Odor was evaluated using the "Sniffin' Sticks" test kit, which assessed the T (odor threshold), D (odor discrimination), and I (odor identification) parameters. Sinonasal symptoms were evaluated using the SNOT-22 (sinus-nose outcome test) questionnaire. SNA (sella-nasion-A point), SNB (sella-nasion-B point), and ANB (A point-nasion-B point) angles were calculated from maxillofacial tomography and magnetic resonance imaging) to evaluate facial development. Data were compared with those of the healthy control group. We included 30 patients comprising 19 (63.3%) boys and 11 (36.7%) girls, with no age difference between case and control groups.The mean follow-up period was 7 years. Odor test data, cephalometric measurements, and SNOT-22 analysis results showed no statistically significant differences between the two groups. To our knowledge, this is a comprehensive study with the longest follow-up period in terms of evaluation of facial development after EESBS in children to analyze odor using the Sniffin' Sticks test kit and the quality of life using SNOT-22. Olfactory function, facial development, and quality of life remained unaffected after long-term follow-up after EESBS in children. Although this surgical approach is minimally invasive, we recommend considering the possibility of complications, and the procedure should be performed by an experienced surgical team with adequate equipment.

PEMODELAN KUALITAS AIR TANAH OLEH AIR LIMBAH DOMESTIK MENGGUNAKAN ARCGIS DI DESA KERTALANGU

<p><em>The community living in Kesiman Kertalangu Village, East Denpasar, Denpasar City, Bali, has a few open shallow wells at home. Well water is used for daily activities such as washing, washing vehicles, and watering plants. The main source of water is groundwater, which is found in rocks below the earth's surface. The availability and movement of groundwater depends on the geological conditions of the area.</em><em> </em><em>Groundwater that is used as a source of community life must meet good water quality, so the purpose of this study was to determine the condition of groundwater during the study. The samples used for groundwater testing were 30 wells spread across this village. The methods used were interviews with the local community, field testing of well water samples (smell and temperature tests), laboratory tests (pH, TSS, TDS, DHL and microbiology) and modeling analysis of all research data results using the ARCGIS application. The research results obtained were field tests such as odor tests and temperature tests that passed the clean water requirements because they met the standards set by the Ministry of Health. laboratory tests such as the TDS, TSS and DHL tests have met the requirements as clean water because the number of solid particles dissolved in water and gas is below the specified limits, and the amount of suspended solids in water is also below the limits. Microbiological test results showed that several points were quite polluted by E.Coli and Total Coliform bacteria caused by the distance between the well points and the septic tank in people's homes.</em></p>

Does experience of music enhance olfaction: music as a potential nutrition intervention?

Olfaction, the sense of smell, is under recognised and underappreciated despite being vital in wellbeing. It confers a major influence on the feeding process being the major contributor of flavour and has a direct involvement in the cephalic phase responses. Along with its influence on food and nutrition, olfaction is directly associated with cognitive function and impacts social communication and safety(1). Loss of olfactory acuity, commonly occurring in aging and frailty, significantly influences dietary behaviour and food selection(2). Unlike the senses of vision and audition, interventions are lacking. We propose in a proof-of-concept that crossmodal integration of olfaction and audition could inhibit olfactory decline in lifelong musicians through encouraging neuroplasticity of the olfactory brain centres. Ethical approval was obtained from The University of Adelaide Human Research Ethics Committee. Male musicians with a lifetime experience of music (ME) and naïve non-musicians (NM) aged 55 years and over were recruited through music organisations and controls through the Australian Men’s Shed network. The initial target sample size was twenty per cohort. Olfactory acuity was assessed with Sniffin’ sticks® (Odofin, Groningen, The Netherlands), a well validated system of a battery of three tests regimes. Sniffin’ sticks represent ‘felt tipped pens’ impregnated with odourants presented 20mm below the nose of participants who were then prompted to ‘sniff’. Assays determined participant ‘Threshold’, ‘Discrimination’ and ‘Identification’ of test odours (3). Measurement of Threshold and Discrimination were undertaken in triplet fifteen seconds apart with eyes closed; measurement of Threshold being conducted in an ascending ‘staircase’ to detect lowest odour concentration detectable, whereas measurement of Discrimination selected the ‘odd-man-out’ of a triplet comprising two identical and one different odour. Measurement of Identification, with eyes open, selected the odour of a single ‘pen’ from a prompt list of four. All tests demanded selection. Each of the test batteries were scored out of sixteen along with total aggregate of Threshold, Discrimination, and Identification (TDI). Twenty-six participants completed the study (18 ME and 8 NM); numbers were limited owing to active COVID-19. Mean and standard deviations (SD) of Threshold, Discrimination, Identification and TDI were derived and compared between groups using ‘t’-test. For ME, Threshold, Discrimination, and Identification values were 6.2 (SD ± 3.7), 10.6 (SD ± 1.9), and 12.9 (SD ± 1.6). The respective values for NM were 5.0 (SD ± 2.3), 8.8(SD ± 2.9), and 10.8 (SD ± 2.5). The ME group showed a significantly higher Discrimination (p = 0.164). Significant differences were not seen for Threshold, Identification, and overall TDI scores, however the small sample size may have accounted for this. Based on this proof-of-concept, further exploration of music is warranted as an intervention to enhance olfactory acuity to potentially improve the intake of food and nutrition, and enrich pleasure of eating and drinking, and quality of life.

Analysis of substances contributing to the coffee flavor using headspace－GC-MS, GPC－GC-MS, and odor test

Analysis of substances contributing to the coffee flavor using headspace－GC-MS, GPC－GC-MS, and odor test

Medical Research Improves Water Taste and Odor Testing

Water scientists looked to medical experts to delve into the human sensory system, reinforcing the need for water laboratory staff to be sensitive to any odors present in their systems.

FORMULATION OF HERBAL SOAPS FROM PHYLLANTHUS RETICULATUS FRUITS AND TECTONA GRANDIS LEAVES AND EVALUATION OF ITS PHYSICOCHEMICAL PROPERTIES

The present investigation aimed to develop and evaluate the herbal soap by aqueous extracts of Tectona grandis leaves and fruits of Phyllanthus reticulatus. The herbal formulation was then subjected to phytochemical screening and evaluated for colour, pH, odour, texture, foaming ability, moisture content and irritation test. The results demonstrated that the herbal soaps revealed the presence of alkaloids, tannins, flavonoids and anthocyanins. The physicochemical results were satisfactory for both the herbal soaps. No such studies related to the preparation of soaps using these extracts have been done so far. Hence, the present study was of great importance and could serve as an alternative to chemical soaps.

QUALITY OF BALINESE BEEF PRODUCED BY PESANGGARAN SLAUGHTERHOUSE WITH ABIANSEMAL VILLAGE ABATTOIRS

The increasing demand for beef causes the intensity of cattle slaughter to increase. This makes the existence of slaughterhouses (RPH) and abattoirs (TPH) indispensable in supporting the availability of meat in an area. The purpose of this study was to determine the quality of Balinese beef in terms of subjective and objective tests and to determine the difference in the quality of Balinese beef produced by Pesanggaran slaughterhouses and Abiansemal Village of abattoirs. The samples used in this study were Balinese beef slaughtered at Pesanggaran slaughterhouses and Abiansemal Village abattoirs, at the silver side (M. biceps femoris) as much as 125 grams/head of 16 meat samples. Each sample was subjectively (color test, odor test, consistency test, and texture test) and objectively (pH test, water binding capacity test, and moisture content test) tested for physical quality. Subjective data was analyzed by Mann Whitney test and objective data was tested by T test (Independent). The results of the subjective data research with the Mann Whitney test obtained the results of the color test of Balinese beef produced by RPH Pesanggaran and TPH Abiansemal Village respectively 6.03 and 8.77, the odor test both had a score of 2, the consistency test had a score of 2.6 and 1.8, the texture test had a score of 2.43 and 1.38. While the T Test (Independent) test for objective data obtained the pH test results of 5.48 and 5.6, respectively, the water binding capacity test was 73.29% and 76.07%, and the water content test was 66.42% and 69.36%. It can be concluded that the quality of Balinese beef from Pesanggaran slaughterhouses and Abiansemal Village abattoirs is in good condition and suitable for consumption. In order to obtain ASUH meat products, it is recommended to carry out guidance on abattoirs in accordance with the standards for slaughtering animals at slaughterhouses.

Physical activity as a promoter of stress resilience: An analysis of behavioral effects and brain connectivity with cytochrome c-oxidase activity in adult male Wistar rats

Physical activity (PA) is very beneficial for physical and mental health. This study aims to examine the resilience-inducting effect of PA in adult male Wistar rats exposed to unpredictable chronic mild stress (UCMS). Furthermore, we analyzed the influence of PA on behavioral tasks and functional brain connectivity with cytochrome c oxidase technique. The cytochrome c oxidase (CCO) is a mitochondrial enzyme involved in oxidative phosphorylation and ATP generation. For this analysis, we included five groups: Basal (n = 10, to determine the basal level of brain activity), Behav (n = 15, subjected exclusively to behavioral tests), PA (n = 10, exposed to physical activity), UCMS (n = 15, subjected to a stress protocol) and PA + UCMS (n = 15, exposed to PA prior to stress). The UCMS protocol consisted of randomly presenting several different stressors over four consecutive weeks. We evaluated several behaviors of the Behav, UCMS, and PA + UCMS groups. This assessment includes the hedonic responses using the sucrose consumption task, unconditioned anxiety with the zero maze, and coping strategies assessed with the cat odor test. The UCMS group showed an anhedonia profile and increased anxiety compared with the other groups. Although in the exposure to cat odor test, the PA + UCMS remained for the same time in the cat odor compartment as the other groups, it did not approach the odor, showing that it detected the risk. This response is more adaptive than the responses of the UCMS and Behav groups. An exploratory analysis of the cerebral connections showed an increase in CCO activity in the UCMS group compared to the other groups. This overactivity was reduced in dorsal Cornu Ammonis 3(dCA3) by prior PA. In this region, PA + UCMS showed similar activity as the groups not subjected to chronic stress. Therefore, PA can prevent the harmful effects of chronic stress on dCA3.

Research on Traceability Method of Emission Compounds from Vehicle Seat Based on GC-IMS

The odor in a car can have a negative impact on human health, mood, and mentality. Therefore, it is imperative to find an appropriate method to trace the odor and identify the substances that cause it. Three odor testing methods were utilized to evaluate seat-related materials. Subjective evaluation still holds an advantage in odor typing, and many odor types of vehicles and seats are inevitably correlated. By combining subjective and objective methods, 11 types of odor substances can be identified using GC-MSODP. Based on these substances, the relationship with the odor type can be determined in a single step. As a purely objective testing method, GC-IMS can identify 16 types of odor substances by leveraging its principle advantages, which can replace the olfactory identification of the ODP process, reduce harm to personnel, and also facilitate large-scale testing. Degree analysis and other procedures can be employed to effectively control product consistency. However, to achieve better odor traceability and consistency control, it is necessary to develop accurate quantitative methods for GC-IMS.

Perbandingan Efektivitas Bioaktivator MOL Kulit Pisang Kepok (Musa paradisiaca L.) dan EM4 Dalam Pengomposan Limbah Daun Srobilanthes cusia Secara Aerob

The production process of natural indigo dye from the Strobilanthes cusia plant has solid leaf waste as a by-product from maceration residue. This waste can be used to make solid organic fertilizer. This research aims to determine the effective concentration of adding local microorganism (MOL) of kepok banana peel and EM4 to bioactivators obtain good quality compost. Composting was carried out aerobically with variations in the concentration ratio of kepok banana peel MOL and EM4 bioactivators of 1%, 2%, 3%, 4% and 5% respectively. Fertilizer quality is determined by testing the C/N ratio parameter using the Walkey & Black (C-Organic) and Kjeldahl (N-Total) methods. Color, texture and odor tests were carried out organoleptically by 5 panelists. The results showed that in the concentration range of 1-5%, the MOL kepok banana peel bioactivator was more effective than EM4, as evidenced by the lower C/N ratio of the compost. The best product was obtained from the composting process with 5% MOL kepok banana peel bioactivator with a C/N ratio of 50.04%, water content of 48.74%, blackish brown color, very crumbly texture and an earthy smell. This result does not meet the standards for compost quality according to SNI 19-7030-2004, but the physical parameters such as color, texture, odor and water content meet the standards, namely blackish brown color, very crumbly texture and smells like soil.

ANALISIS MUTU ORGANOLEPTIK DAN UJI Salmonella sp. PADA IKAN CAKALANG ASAP DI PASAR REMU, KOTA SORONG

Smoked skipjack is a type of product that is sold in many markets in Indonesia, including at Remu Market, Sorong City. However, the quality and safety of smoked skipjack tuna is a matter that needs to be considered by the public as consumers. The research method used was a descriptive study by observing the organoleptic quality of smoked skipjack tuna and detection on Salmonella sp..The results of this study showed that the organoleptic quality value of the appearance of the P sample of smoked skipjack tuna at the Remu market, Sorong city had the highest value of 8.87, then the highest odor test was 8.73, the taste value was 8.93, and the value of the texture was 8.40. However, the value of mushrooms and slime from the three samples showed the same value (9.0) which indicates that there was no fungus and slime in the smoked skipjack tuna observed. The results of the detection test Salmonella sp. showed that the P sample was safe from contamination by Salmonella sp. compared to sample R and sample Q.

Olfactory dysfunction and training in children with COVID-19 infection: A prospective study Post-COVID pediatric olfactory training

ObjectivePostviral olfactory dysfunction (OD) including corona 2019 viral disease (COVID-19) OD occurs in both adults and children. Despite limited reports of efficacy in treating adult postviral including COVID-19 OD with olfactory training (OT), its effects on children in general, and post-COVID-19 in specific, is unknown. The study aimed at evaluating the effects of OT in a COVID-19 OD pediatric cohort. MethodsA single-arm prospective study of pediatric COVID-19 OD subjects confirmed by the University of Pennsylvania Smell Identification Test (UPSIT), was conducted. All subjects underwent OT by sniffing 4 odorants (lavender, orange, peppermint, and eucalyptus) for 1 min twice a day for 3 months. Subjects underwent an odorant identification test (OIT) of the 4 odorants each visit. A repeat UPSIT was administered at the 4th visit. ResultsThe study enrolled a total of 37 subjects [11 males/26 females with mean age/standard deviation (std) of 15.6(2.1) years]. The time interval between COVID-19 and entry was 5.3(2.4) months. The mean pre/post study UPSIT score improvement was 2.3(4.7), p = .09. OIT scores between entry and 3 subsequent visits showed a mean improvement of 1.8(1.5), 1.8(1.9) and 2.3(1.9) odorants, respectively, with P < .001 for all 3 comparisons. ConclusionsOT subjects were predominantly female teens with substantial OD lasting greater than 5 months. OT did not affect OD as measured by UPSIT but OIT scores improved during OT. We postulate that OT likely has a role in pediatric post-COVID OD recovery, but UPSIT likely is too rigid to detect disparate odorant improvement.

UPSIT subitems may predict motor progression in Parkinson's disease.

The relationship between hyposmia and motor progression is controversial in Parkinson's disease (PD). The aim of this study was to investigate whether preserved identification of Chinese-validated University of Pennsylvania Smell Identification Test (UPSIT) odors could predict PD motor progression. PD patients with two consecutive clinical visits while taking medication were recruited. Based on mean changes in Movement Disorder Society Unified Parkinson's Disease Rating Scale part 3 score and levodopa equivalent daily dosage, the participants were categorized into rapid progression, medium progression, and slow progression groups. Odors associated with the risk of PD motor progression were identified by calculating the odds ratios of UPSIT item identification between the rapid and slow progression groups. Receiver operating characteristic curve analysis of these odors was conducted to determine an optimal threshold for rapid motor progression. A total of 117 PD patients were screened for group classification. Preserved identification of neutral/pleasant odors including banana, peach, magnolia, and baby powder was significantly correlated with rapid motor progression. The risk of rapid progression increased with more detected risk odors. Detection of ≥1.5 risk odors could differentiate rapid progression from slow progression with a sensitivity of 85.7%, specificity of 45.8%, and area under the receiver operating characteristic curve of 0.687. Preserved identification of neutral/pleasant odors may help to predict PD motor progression, and detection of ≥1.5 UPSIT motor progression risk odors could improve the predictive power. In PD patients with a similar level of motor disability during initial screening, preserved pleasant/neutral odor identification may imply relatively better cortical odor discriminative function, which may suggest the body-first (caudo-rostral) subtype with faster disease progression.

A perspective of randomness in a clinical test of olfactory performance

Random walks describe stochastic processes characterized by a sequence of unpredictable changes in a random variable with no correlation to past changes. This report describes the random walk component of a clinical sensory test of olfactory performance. The precise definition of this stochastic process allows the establishment of precise diagnostic cut-offs for the identification of olfactory loss. Within the Sniffin`Sticks olfactory test battery, odor discrimination (D) and odor identification (I) are assessed by four- and three-alternative forced-choice designs, respectively. Meanwhile, the odor threshold (T) test integrates a three-alternative forced-choice paradigm within a staircase paradigm with seven turning points. We explored this paradigm through computer simulations and provided a formal description. The odor threshold assessment test consists of two sequential components, the first of which sets the starting point for the second. Both parts can be characterized as biased random walks with significantly different probabilities of moving to higher (11%) or lower (89%) values. The initial odor concentration step for the first phase of the test and the length of the subsequent random walk in the second phase significantly affect the probability of randomly achieving high test scores. Changing the odor concentration from where the starting point determination for the second test part begins has raised the current cut-off for anosmia, represented as T + D + I < 16, from the 87th quantile of random test scores to the 97th quantile. Analogous findings are likely applicable to other sensory tests that use the staircase paradigm characterized as random walk.

The Olfaction Ability of Medical Detection Canine to Detect Prostate Cancer From Urine Samples: Progress Captured in Systematic Review and Meta-Analysis.

To date, early cancer detection is considered vital to reduce the global cancer burden through low-cost, but accurate screening modalities. The anatomical positioning of prostate cancer (PCa) created a potentially distinctive diagnostic method through the identification of volatile organic compounds (VOCs) in urine, which might be detectable not by humans but by canine species. This review aimed to capture the potential of the medical detection canine (MDC) to detect PCa by providing its diagnostic accuracy estimation on urine odor testing. Databases, e.g., MEDLINE, Cochrane, ScienceDirect, and ProQuest, were searched to identify the studies. We focused on accessible original research, comparing the diagnostic utility of trained female MDC and histopathology examination as the gold standard for PCa diagnosis. The statistical analysis was performed in Meta-DiSc 1.4 and presented in diagnostic values, i.e., sensitivity (Sn), specificity (Sp), positive or negative likelihood ratio (LR+ or LR-), diagnostic odd ratio (DOR), and area under the curve (AUC) value, to conclude the Sn-Sp in a single outcome. Female German Shepherds were the most commonly utilized MDC from the five studies included in the final analysis. We estimate the pooled diagnostic value of eight different MDCs, with the findings as follows: Sn (0.95 (0.94 - 0.97)), Sp (0.92 (0.90 - 0.93)), LR+ (4.48 (1.90 - 10.58)), LR- (0.12 (0.01 - 1.42)), DOR (35.39 (2.90 - 432.53)), and an AUC value of 0.9232. MDC's olfaction ability holds considerable potential on its diagnostic accuracies to distinguish the urine of PCa individuals by identifying its volatilome property.

Association of APOE ε4 Status With Long-term Declines in Odor Sensitivity, Odor Identification, and Cognition in Older US Adults.

The APOE ε4 allele confers susceptibility to faster decline in odor identification and subsequently to Alzheimer disease (AD). Odor identification requires recognizing and naming odors and detecting them (odor sensitivity). Whether APOE ε4 is associated with decline of odor sensitivity and whether such decline serves as a harbinger of cognitive decline and AD remains unclear. We determined whether and when APOE ε4 affects decline in odor sensitivity, odor identification, and cognition in the National Social Life Health and Aging Project (NSHAP). We used data from NSHAP, a nationally representative survey study of home-dwelling US older adults. Olfaction was measured over time (odor identification in 2005, 2010, and 2015; odor sensitivity in 2010 and 2015; both using validated tests). Cognition was measured with a modified version of the Montreal Cognitive Assessment in 2010 and 2015. Genotyping was performed using DNA samples collected in 2010. Odor sensitivity and identification were compared among APOE ε4 carriers and noncarriers stratified by age. Relationships between APOE ε4, odor sensitivity, odor identification, and cognition were analyzed in cross-section using ordinal logistic regression and longitudinally using mixed-effects models adjusted for confounders. Odor sensitivity was measured in 865 respondents, odor identification in 1,156 respondents, and cognition in 864 respondents; all these respondents had genetic data available. Odor sensitivity deficits in APOE ε4 carriers were apparent at ages 65-69 years, whereas odor identification deficits did not appear until ages 75-79 years. Subsequently, odor sensitivity did not decline more rapidly with aging in APOE ε4 carriers compared with that in noncarriers (carrier status and aging interaction: odds ratio [OR] 1.44, 95% CI 0.94-2.19, p = 0.092), whereas odor identification declined more rapidly in carriers (aging 10 years interaction: OR 0.26, 95% CI 0.13-0.52, p < 0.001). As expected, and in parallel to odor identification, cognition declined more rapidly in APOE ε4 carriers (interaction: OR 0.55, 95% CI 0.34-0.89, p = 0.015). APOE ε4 affects decline of odor sensitivity earlier than odor identification or cognition. Thus, testing odor sensitivity may be useful to predict future impaired cognitive function. Identifying the mechanism underlying these relationships will elucidate the key role of olfaction in neurodegeneration during aging.

Olfaction evaluation in dogs with sudden acquired retinal degeneration syndrome.

To evaluate olfaction in dogs with sudden acquired retinal degeneration syndrome (SARDS) compared with sighted dogs and blind dogs without SARDS as control groups. Forty client-owned dogs. Olfactory threshold testing was performed on three groups: SARDS, sighted, and blind/non-SARDS using eugenol as the test odorant. The olfactory threshold was determined when subjects indicated the detection of a specific eugenol concentration with behavioral responses. Olfactory threshold, age, body weight, and environmental room factors were evaluated. Sixteen dogs with SARDS, 12 sighted dogs, and 12 blind/non-SARDS dogs demonstrated mean olfactory threshold pen numbers of 2.8 (SD = 1.4), 13.8 (SD = 1.4), and 13.4 (SD = 1.1), respectively, which correspond to actual mean concentrations of 0.017 g/mL, 1.7 × 10-13 g/mL and 4.26 × 10-13 g/mL, respectively. Dogs with SARDS had significantly poorer olfactory threshold scores compared with the two control groups (p < .001), with no difference between the control groups (p = .5). Age, weight, and room environment did not differ between the three groups. Dogs with SARDS have severely decreased olfaction capabilities compared with sighted dogs and blind/non-SARDS dogs. This finding supports the suspicion that SARDS is a systemic disease causing blindness, endocrinopathy, and hyposmia. Since the molecular pathways are similar in photoreceptors, olfactory receptors, and steroidogenesis with all using G-protein coupled receptors in the cell membrane, the cause of SARDS may exist at the G-protein associated interactions with intracellular cyclic nucleotides. Further investigations into G-protein coupled receptors pathway and canine olfactory receptor genes in SARDS patients may be valuable in revealing the cause of SARDS.