Olfaction Research Articles

Sense of smell reduction as factor for mammoth’s and other mammals extinction. Immunoglobulins as possible markers

One of the possible mechanisms for the extinction of animals during climate change could be a violation of the sense of smell due to the development of allergies when the flora changes. During the breeding season, susceptibility to odors is very important for animals. The development of allergies from plant pollen, changes in pollen's allergic toxicity, pollen's release period increasing or the emergence of a large quantity of flowering plants during climate change, could lead to decrements in sensitivity to odors in animals during the breeding season. This may explain the extinction of animals due to a decrease in sexual intercourse. Probably these changes in allergic responses of mammoths at period of climate changes led to a decrease in the mammoth population and, as a result, to their disappearance. For example, elephants have the most sensitive sense of smell. Immunoglobulin’s traces can provide information about the health of extinct animals. The search and characterization of immunoglobulins from extinct animals and comparison with the plant composition (pollen, plant remains) found with the animals can provide information about possible allergic diseases of these animals.The purpose of our article is to show that immunoglubulin’s fragments found in the remains of mammoths indicate the presence of possible allergic diseases in mammoths. Also, the purpose of this work is to propose a new evolutionary mechanism for the extinction of mammoths and other animals based on the disruption of communications between animals during the breeding season due to a decrease in the sense of smell and sensitivity to odors due to allergies to plants.

Olfactory facilitation of visual categorization in the 4-month-old brain depends on visual demand.

To navigate their environment, infants rely on intersensory facilitation when unisensory perceptual demand is high, a principle known as inverse effectiveness. Given that this principle was mainly documented in the context of audiovisual stimulations, here we aim to determine whether it applies to olfactory-to-visual facilitation. We build on previous evidence that the mother's body odor facilitates face categorization in the 4-month-old brain, and investigate whether this effect depends on visual demand. Scalp electroencephalogram (EEG) was recorded in two groups of 4-month-old infants while they watched 6-Hz streams of visual stimuli with faces displayed every 6th stimulus to tag a face-selective response at 1Hz. We used variable natural stimuli in one group (Nat Group), while stimuli were simplified in the other group (Simp Group) to reduce perceptual categorization demand. During visual stimulation, infants were alternatively exposed to their mother's versus a baseline odor. For both groups, we found an occipito-temporal face-selective response, but with a larger amplitude for the simplified stimuli, reflecting less demanding visual categorization. Importantly, the mother's body odor enhances the response to natural, but not to simplified, face stimuli, indicating that maternal odor improves face categorization when it is most demanding for the 4-month-old brain. Overall, this study demonstrates that the inverse effectiveness of intersensory facilitation applies to the sense of smell during early perceptual development. RESEARCH HIGHLIGHTS: Intersensory facilitation is a function of unisensory perceptual demand in infants (inverse effectiveness). This inverse relation between multisensory and unisensory perception has been mainly documented using audiovisual stimulations. Here we show that olfactory-to-visual facilitation depends on visual demand in 4-month-old infants. The inverse effectiveness of intersensory facilitation during early perceptual development applies to the sense of smell.

AROMA THERAPY INTERVENTION TO IMPROVING SLEEP QUALITY IN PATIENTS WITH CARDIOVASCULAR PROBLEMS

Background: Poor sleep quality will lead to stressful conditions which can cause the release of epinephrine and norepinephrine has the effect of increasing the oxygen demand for the myocardium. Aromatherapy is recommended as a no-side-effect, non-invasive, inexpensive and painless method to reduce anxiety and pain. improve sleep quality of cardiovascular patients. Purpose: The aim of this study is to analyze the potential of aromatherapy interventions in patients with cardiovascular disorders. Methods: The research method in this article uses a literature study approach. The articles will be selected based on the following criteria. The search sources in this article use scientific-based databases (ScienceDirect, PubMed, EBSCOhost, and Wiley Library Online). The search starts from December 2022 using the keywords Cardiac Patients – Aromatherapy – Sleep quality. Result: Inhalation aromatherapy with peppermint or lavender essential oil can improve the sleep quality of cardiovascular patients. Inhaling aromatic oil stimulates the sense of smell affecting the central nervous system. Lavender oil can reduce fatigue, anxiety, heart rate, respiratory rate, and blood pressure, improve lung and brain oxygenation, and improve sleep quality. The use of essential oils can be a safe and cost-effective therapy for sleep disorders and can reduce the overuse of prescription medications. Implication: Lavender and peppermint essential oils have a therapeutic effect that relaxes the body. These effects can make the body feel relaxed and release hormones that can help patients sleep. However, this intervention still needs further research specifically from the aspect of dose and medium of aromatherapy.

The complexities of blood-feeding patterns in mosquitoes and sandflies and the burden of disease: A minireview.

Mosquitoes and sandflies exhibit a wide range of blood feeding patterns, targeting a wide range of vertebrate species, including birds, mammals, reptiles, and amphibians, for proteins vital for egg development. This broad host range increases the opportunity for them to acquire pathogens of numerous debilitating-and-fatal diseases from various animal reservoirs, playing a significant role in disease crossover between animals and humans, also known as zoonotic transmission. This review focuses on the intricate blood-feeding habits of these dipteran vectors, their sensory systems and the complex dance between host and pathogen during disease transmission. We delve into the influence of blood sources on pathogen spread by examining the insect immune response and its intricate interplay with pathogens. The remarkable sense of smell guiding them towards food sources and hosts is explored, highlighting the interplay of multiple sensory cues in their navigation. Finally, we examine the challenges in mosquito control strategies and explore innovations in this field, emphasizing the need for sustainable solutions to combat this global health threat. By understanding the biology and behaviour of these insects, we can develop more effective strategies to protect ourselves and mitigate the burden of vector-borne diseases.

Intranasal Trigeminal Function in Aging Adults.

Intranasal trigeminal function is important in detecting environmental stimuli. The impact of age-associated chemosensory dysfunction upon taste and olfaction is well described, but an understanding of trigeminal loss (chemesthesis) is lacking. The goal of this study was to characterize trigeminal function in a cohort of older adults and explore potential impacts. Twenty-eight participants over 50 years of age were recruited from the community as part of an aging cohort study. This nested cohort completed chemosensory questionnaires, patient-reported outcome measures (PROMs), and psychophysical testing for taste (taste strips), olfaction (Sniffin' Sticks), and trigeminal function (eucalyptol lateralization). Data were analyzed for associations between trigeminal function, olfactory, and taste psychophysical performance, patient-reported metrics, and demographic risk factors. Patient-reported trigeminal impairment is less severe than other chemosensory loss, with mean visual analog scores (VAS, rated 0-100 from least to most severe) for smell (32.9 ± 34.2), taste (20.6 ± 28.4), and trigeminal sensation (9.5 ± 12.8). Despite low VAS scores, psychophysical trigeminal dysfunction was present in 10 (35.7%) subjects. Psychophysical olfactory and taste dysfunction were present in 16 (57.1%) and eight (28.6%) participants respectively. Hypercholesterolemia was associated with psychophysical trigeminal dysfunction (mean lateralization performance in hypercholesterolemia 57.7% ± 17.1 vs. 74.1% ± 10.4, p = .008). Intranasal trigeminal impairment is present in nearly one-third of aging adults when assessed by psychophysical methods but is under-recognized. Hyperlipidemia may be associated with trigeminal impairment. Future inquiries should better characterize these findings in larger and prospective cohorts.

Conservation and selective pressures shaping baleen whale olfactory receptor genes supports their use of olfaction in the marine environment.

The relative importance of various sensory modalities can shift in response to evolutionary transitions, resulting in changes to underlying gene families encoding their reception systems. The rapid birth-and-death process underlying the evolution of the large olfactory receptor (OR) gene family has accelerated genomic-level change for the sense of smell in particular. The transition from the land to sea in marine mammals is an attractive model for understanding the influence of habitat shifts on sensory systems, with the retained OR repertoire of baleen whales contrasting with its loss in toothed whales. In this study, we examine to what extent the transition from a terrestrial to a marine environment has influenced the evolution of baleen whale OR repertoires. We developed Gene Mining Pipeline (GMPipe) (https://github.com/AprilJauhal/GMPipe), which can accurately identify large numbers of candidate OR genes. GMPipe identified 707 OR sequences from eight baleen whale species. These repertoires exhibited distinct family count distributions compared to terrestrial mammals, including signs of relative expansion in families OR10, OR11 and OR13. While many receptors have been lost or show signs of random drift in baleen whales, others exhibit signs of evolving under purifying or positive selection. Over 85% of OR genes could be sorted into orthologous groups of sequences containing at least four homologous sequences. Many of these groups, particularly from family OR10, presented signs of relative expansion and purifying selective pressure. Overall, our results suggest that the relatively small size of baleen whale OR repertoires result from specialisation to novel olfactory landscapes, as opposed to random drift.

Binding characterization of odorant-binding protein BhorOBP29 in Batocera horsfieldi (Hope) with host-plant volatiles

Odorant binding proteins (OBPs) are involved in odorant discrimination and act as the first filter in the peripheral olfactory system. Previous studies have shown that BhorOBP29 is potentially involved in olfactory perception in an important wood-boring pest Batocera horsfieldi (Hope) (Coleoptera: Cerambycidae), however, its function remains unclear. Here, we investigated the ligand-binding profiles of recombinant BhorOBP29 with 22 compounds from its host plant using fluorescence competitive binding assays and fluorescence quenching assays. The results showed that BhorOBP29 could bind to five ligands relying mainly on hydrophobic interactions. Molecular docking analysis indicated that residues Ile48, Leu51, Met52, Trp57, Asn105, and Val119 were extensively involved in the interactions between BhorOBP29 and the five ligands. Furthermore, the site-directed mutagenesis analysis revealed that Leu51 and Met52 residues were indispensable for BhorOBP29-ligands binding. Finally, electroantennogram (EAG) assays confirmed that hexanal, (−)-limonene, and 2-methylbutyraldehyde elicited a concentration-dependent EAG response with a maximum at the concentration of 1/10 v/v. These findings suggest that BhorOBP29 may play a significant role in the perception of host plant volatiles by B. horsfieldi. This study may help to discover novel behavioral regulation and environmentally friendly strategies for controlling B. horsfieldi in the future.

Flavoromic analysis of wines using gas chromatography, mass spectrometry and sensory techniques

Various sensory perceptions drive the quality and typicality of wines, with the volatile profile playing a fundamental role in the characteristics of odor, aroma and consequently flavor, which combines the smell (odor and aroma), taste, and trigeminal sensations. Efforts have been made in both the field of instrumental and sensory analysis to understand the relationship of volatile compounds with sensory attributes in omics approaches. Gas chromatography (monodimensional and two-dimensional (heartcutting and comprehensive)) associated with mass spectrometry (GC/MS, GC-GC/MS and GCxGC/MS) and chemometric tools have contributed to foodomics analyses, specifically those linked to metabolomics/volatilomics. These tools, along with the elucidation of sensory properties (sensomics), lead to advanced results in the field of flavoromics. They also help to define the best practices in both vineyard management and winemaking that enable the production of high-quality wines. The objective of this review is to report the challenges of determining the volatile profile of wines, pointing out the ways that can be followed in successful identification and quantification of volatile compounds. The state of the art of sensory evaluation methods is also addressed, providing information that helps in choosing the most appropriate sensory method to be conducted with chromatographic analysis to achieve more in-depth results in the field of flavoromics.

Pengaruh Pemberian Baby Massage Lavender Essential Oil terhadap Peningkatan Kualitas Tidur pada Bayi Usia 3-12 Bulan

Background : poor sleep quality in babies will result in decreased immunity, impaired growth and physical development, and have an impact on the growth and development of the baby's brain. 1 year of age is a golden period for brain development. Baby Massage is a type of stimulation that will stimulate the development of the structure and function of cells in the brain. The improvement in the quality of baby's sleep during baby massage is due to an increase in the levels of serotonin secretion produced during massage. Apart from the Baby Massage method, adding Lavender Essential Oil also has an effect on improving the quality of baby's sleep because essential oil can influence brain function activities through the nervous system which is related to the sense of smell. Lavender contains esters which can calm and have a direct effect on the nervous system. Objective: to determine the effect of giving Baby Massage lavender essential oil on improving the sleep quality of babies aged 3-12. Method: Pre-Experiment with One Group Pretest Posttest design. Sample of 30 respondents. Respondents were given a massage once and then evaluated after 24 hours. Data analysis used the Wilcoxon test. Results: The quality of sleep before being given Baby Massage Lavender Essential was that all 30 respondents had poor sleep quality. The majority of sleep quality after being given Baby Massage Lavender Essential was good, namely 27 respondents (90%). The statistical test obtained a p-value of 0.000, <0.05. Conclusion: There is an effect of giving Baby Massage lavender essential oil on improving the sleep quality of babies aged 3-12.

Subjective and objective effects of radioiodine therapy on the sense of smell.

Evaluating the impact of radioiodine therapy (RIT) on olfactory function in thyroid cancer patients through quantitative and qualitative olfactory tests. In this cohort study, patients with thyroid cancer were included. Demographic, clinical, and laboratory data were collected. To subjectively evaluate the olfactory changes aftter RIT, the Visual Analog Scale (VAS), Self-Reported Mini-Olfactory Questionnaire (self-MOQ), and the University of Washington Quality of Life Questionnaire (UW-QOL) were assessed. Out of UW-QOL questions those related to saliva, taste, and overall health condition were analysed. For objective assessment, patients underwent both the Butanol Threshold Test (BTT) and the a version of Smell Identification Test (SIT). Patients were assessed before, one month, and six months after RIT. Ninety eight patients were included (Male = 17). A statistically significant decrement was observed in olfaction based on the VAS, between the baseline and one (pvalue = 0.015) and six months (pvalue = 0.031) of follow-up. Additionally, saliva (pvalue = 0.001), taste (pvalue = 0.000), and overall health condition (pvalue = 0.010) significantly decreased one-month after RIT. The measures were not different between the baseline and 6-month follow up and the improvement of index of taste was significant from 1-month to 6-months follow ups (pvalue = 0.000). However, none of the objective tests (the BTT and the SIT) indicated a significant decline in olfaction during the follow up. A subjective RIT related decrease in smell function, taste, and saliva production was documented without any objective olfactory dysfunction.

The Application Of Medication And Strategies For The Implementation Of Hallucinations In Tn. S (Terra Neutral Separated) With A Nursing Diagnosis Of Sensory Perception Disorders (Hallucinations)

Hallucinations are sensory perception disorders that attack the five senses, where a person perceives an object or image and thoughts that do not occur or are not real. Hallucinations include sound, sight, taste, touch, or smell sensations without real stimulus. Treatment for patients with hallucinations is by identifying the type of hallucination, applying medication, and implementing strategies to distract or overcome the hallucinations experienced. The objectives of this study include (1) Describing problems regarding sensory perception disorders and (2) Describing and implementing nursing care in cases of mental disorders with a medical diagnosis of schizophrenia at Soerojo Hospital Magelang. This study uses a qualitative approach with case studies as the primary method, using observation sheets, interviews, and documentation studies. The subject of this study used one patient, Mr S, who had a nursing diagnosis of sensory perception disorders at RSD Soerojo Hospital Magelang. Nursing care for patient Mr S with a diagnosis of sensory perception disorder (hallucinations) in this case showed success as indicated by the signs and symptoms experienced by the patient decreasing. After four days of intervention, the patient was able to overcome hallucinations by scolding, interacting with the surrounding environment, and taking care of himself by bathing and dressing more neatly.

Genome-Wide Association Study Meta-Analysis Uncovers Novel Genetic Variants Associated with Olfactory Dysfunction.

Olfactory dysfunction is among the earliest signs of many age-related neurodegenerative diseases and has been associated with increased mortality in older adults; however, its genetic basis remains largely unknown. To identify the genetic loci associated with olfactory dysfunction in the general population. This genome-wide association study meta-analysis (GWMA) included participants of European ancestry (N = 22,730) enrolled in four different large population-based studies, followed by a multi-ancestry GWMA including participants of African ancestry (N = 1,030). The data analysis was performed from March 2023 through June 2024. Genome-wide single nucleotide polymorphisms. Olfactory dysfunction was the outcome and assessed using a 12-item smell identification test. GWMA revealed a novel genome-wide significant locus (tagged by rs11228623 at 11q12) associated with olfactory dysfunction. Gene-based analysis revealed a high enrichment for olfactory receptor genes in this region. Phenome-wide association studies demonstrated associations between genetic variants related to olfactory dysfunction and blood cell counts, kidney function, skeletal muscle mass, cholesterol levels and cardiovascular disease. Using individual-level data, we also confirmed and quantified the strength of these associations on a phenotypic level. Moreover, employing two-sample Mendelian Randomization analyses, we found evidence for causal associations between olfactory dysfunction and these phenotypes. These findings provide novel insights into the genetic architecture of the sense of smell and highlight its importance for many aspects of human health.

Receptors Involved in COVID-19-Related Anosmia: An Update on the Pathophysiology and the Mechanistic Aspects.

Olfactory perception is an important physiological function for human well-being and health. Loss of olfaction, or anosmia, caused by viral infections such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has received considerable attention, especially in persistent cases that take a long time to recover. This review discusses the integration of different components of the olfactory epithelium to serve as a structural and functional unit and explores how they are affected during viral infections, leading to the development of olfactory dysfunction. The review mainly focused on the role of receptors mediating the disruption of olfactory signal transduction pathways such as angiotensin converting enzyme 2 (ACE2), transmembrane protease serine type 2 (TMPRSS2), neuropilin 1 (NRP1), basigin (CD147), olfactory, transient receptor potential vanilloid 1 (TRPV1), purinergic, and interferon gamma receptors. Furthermore, the compromised function of the epithelial sodium channel (ENaC) induced by SARS-CoV-2 infection and its contribution to olfactory dysfunction are also discussed. Collectively, this review provides fundamental information about the many types of receptors that may modulate olfaction and participate in olfactory dysfunction. It will help to understand the underlying pathophysiology of virus-induced anosmia, which may help in finding and designing effective therapies targeting molecules involved in viral invasion and olfaction. To the best of our knowledge, this is the only review that covered all the receptors potentially involved in, or mediating, the disruption of olfactory signal transduction pathways during COVID-19 infection. This wide and complex spectrum of receptors that mediates the pathophysiology of olfactory dysfunction reflects the many ways in which anosmia can be therapeutically managed.

Sensory Changes Related to Swallowing in Motor Neurone Disease.

Dysphagia is common in motor neurone disease (MND) and associated with negative health and psychosocial outcomes. Although largely considered a motor disease, a growing body of evidence suggests that MND can also affect the sensory system. As intact sensation is vital for safe swallowing, and sensory changes can influence the clinical management of dysphagia in people living with MND, this review evaluated and summarised the current evidence for sensory changes related to swallowing in MND. Of 3,481 articles originally identified, 29 met the inclusion criteria. Of these, 20 studies reported sensory changes, which included laryngeal sensation, taste, gag reflex, cough reflex, tongue sensation, smell, palatal and pharyngeal sensation, silent aspiration, and undefined sensation of the swallowing mechanism. Sensory changes were either described as decreased (n = 16) or heightened (n = 4). In the remaining nine studies, sensory function was reported as unaffected. The presence of changes to sensory function related to swallowing in MND remains inconclusive, although an increasing number of studies report sensory changes in some sensory domains. Future research is needed to evaluate the prevalence of sensory changes in MND and how such changes may influence dysphagia and its management.

Multidisciplinary approach to severe intracranial, intraorbital allergic fungal sinusitis

BackgroundAllergic fungal sinusitis (AFS) is a form of paranasal mycosis that often involves bone destruction and can extend into the orbit and anterior skull base. Intracranial and intraorbital involvement are published but not both in each included patient of a series. The purpose of the present study was to review cases of extensive AFS with orbital or/and skull base erosion, including the presenting symptoms, patient socioeconomic background, imaging features, surgical technique, and post-operative outcomes. MethodsThe records of 30 patients with the histological diagnosis of AFS and both intracranial and intraorbital involvement were reviewed. ResultsThe average age of the patients was 25.2 years. 83 % of patients were male. 70 % were African American. 66 % of patients had Medicaid or were uninsured. Presenting symptoms were headaches (80 %), nasal obstruction (33 %), proptosis (40 %), vision change (23 %), facial pressure (10 %), and decreased sense of smell (7 %). 100 % of patients had bone erosion observed on computerized tomography scans with disease extending intracranially through the anterior skull base or posterior wall of the frontal sinus along with disease that eroded through the lamina papyracea. All patients had failed medical management. All patients underwent surgery by Otolaryngology, Ophthalmology, and Neurosurgery with transnasal endoscopic approaches and orbitotomy. 80 % also underwent a bifrontal craniotomy for removal of intracranial extradural disease with cranialization. 53 % of patients had orbital implants remaining after surgery; 23 % had nasal stents. There were no postoperative cerebrospinal fluid leaks. Average hospital stay was 4.8 days. Preoperatively, 13 % of patients underwent allergy testing. 94 % saw an Allergist postoperatively. 21 % required follow up surgery. ConclusionsA team approach of Otolaryngologists, Ophthalmologists, and Neurosurgeons is recommended for this slowly growing but locally destructive disease. Most patients with AFS will present with headaches and nasal obstruction. While most cases of AFS can be successfully managed with transnasal endoscopic techniques, orbitotomy and craniotomy represents an effective treatment for severe AFS cases with extensive intracranial and intraorbital involvement. This disease is found most commonly in young African American males and in the underinsured.

The effect of smell training on COVID-19 induced smell loss.

while smell training appears to be effective for post viral smell loss, its effectiveness in COVID-19 induced smell loss is currently not well known. Therefore, we aim to investigate the potential effect of smell training on patients with COVID-19 induced smell loss. we conducted a case-control study with two comparable cohorts. One of which (n=111) was instructed to perform smell training twice daily for 12 weeks, therapeutical adherence was monitored on a daily schedule, while the other cohort (n=50) did not perform smell training. The Sniffin' Sticks Test (SST) was used to objectify participants' sense of smell at baseline and after 12 weeks, reported as a Threshold, Discrimination, and Identification (TDI) score. We also determined the association between therapeutical adherence and the TDI scores. we found a significant difference in psychophysical smell function between patients with COVID-19 induced smell disorders who performed 12 weeks of smell training and those who did not. Median TDI difference between groups was 2.00 However, there was no association between the therapeutical adherence and olfactory function. we discovered a significant moderate difference in psychophysical smell function between patients with COVID-19-induced smell disorders who performed smell training and those who did not, implying a possible advantage of training. However, no relationship was found between therapeutical adherence of smell training and olfactory function.

Effect of Lavender Essential Oil Topical Treatment on the Autonomic Nervous System in Human Subjects Without Olfactory Influence: A Pilot Study

Objective/background As part of a scientific study into the effects of aromatherapy, we investigated the effects of lavender essential oil (LEO) treatment on the autonomic nervous system in subjects for whom the sense of smell had been eliminated. Methods This study used a single-blinded cross-over design for verification. Heart rate variability was measured and effects on the autonomic nervous system were investigated. Results and discussion Although no significant differences were found, aromatherapy treatment with 1% LEO tended to increase parasympathetic nervous system activity. Further, when differences between values before and during aromatherapy treatment were compared, LEO treatment significantly increased parasympathetic nervous system activity. Given these findings, LEO appears to increase parasympathetic nervous system activity, even in the absence of a psychological effect due to an absence of olfactory stimulation. Conclusion The present results provide a scientific method for verifying the effects of aromatherapy and will aid in further elucidation of aromatherapy.

The Association of Odor Identification With Nutritional Status and Systemic Inflammation in Patients With Advanced Chronic Kidney Disease

BackgroundAnorexia is common in patients with chronic kidney disease (CKD) and could lead to protein energy wasting (PEW). An altered sense of smell, a reflection of olfactory dysfunction, is a potential mechanism that exacerbates the impact of anorexia on PEW. In this study, we examined the extent of the altered sense of smell and its association with PEW in patients with moderate to advanced CKD. MethodsWe studied 139 individuals (34 healthy subjects - controls, 50 patients with stage 3-4 CKD, 55 patients on maintenance hemodialysis - MHD) using the odor identification test (Sniffin’ Sticks odor screening test containing 12 different smells). The odor identification test was scored as either correct or incorrect, and each participant's total odor score was calculated. Malnutrition Inflammation Score (MIS) was used to assess PEW. ResultsPatients with CKD had higher C-reactive protein (CRP) and lower serum albumin concentrations compared to healthy individuals. Total odor scores were different between groups, with controls having the highest scores and MHD patients having the lowest scores. A similar difference was observed in MIS, MHD patients displaying the worst nutritional score (p ≤ 0.001). The number of participants with severe olfactory dysfunction (≤ 6 correct answers) was significantly higher in the CKD and MHD groups compared to the controls (p ≤ 0.01). There was an inverse trend between the total odor score and the MIS score for the study population. However, this relationship was not statistically significant (r = -0.124, p = 0.21). ConclusionThis cross-sectional study suggests that olfactory dysfunction, as assessed by the odor identification test, is altered in patients with advanced CKD, most notably in ones on MHD. Although the diminished sense of smell was observed alongside development of PEW, we explicitly noted that there is no statistically significant correlation.

Olfactory perceptual fingerprints of people with olfactory dysfunction and healthy controls.

An olfactory perceptual fingerprint (OPF) defines one's olfactory perception using perceptual descriptor ratings (such as odor pleasantness, intensity) for a set of odors. OPFs have been shown to distinguish patients with COVID-related olfactory dysfunction (OD) and healthy controls with 86% accuracy. However, all participants rated the same odorants. With the aim to evaluate whether the OPFs are indeed odorant independent, previously published dataset by Lötsch et al. was reanalyzed. Furthermore, this independent dataset was used to check whether the OPFs separate patients with OD due to various causes from controls. The study included 104 controls and 42 patients, who were randomized into four odor sets with 10 odorants each. Odorants were presented using a computer-controlled olfactometer and evaluated on scales from 1 (not at all) to 5 (very) using perceptual descriptors pleasant, intensive, familiar, edible, irritating, cold/warm, and painful. Permutational multivariate analysis of variance showed that the odor set did not have a significant effect on the OPFs, confirming that the OPFs are indeed odorant independent. On the other hand, both diagnosis and age affected the OPFs (p < .001) and explained around 11% and 5% of the variance of the OPFs, respectively. Furthermore, a supervised machine learning method, random forest classifier, showed that OPF can distinguish patients and controls with 80% accuracy. OPFs are odorant independent. Patients perceived odors as less familiar, less intense, and less edible than controls. Other perceptual descriptors were much less important for the separation of patients and controls. 3.

SNOT-22 in general population, a Spanish cohort study with an updated meta-analysis.

Olfactory loss (OL) has emerged as one of the most prevalent and debilitating symptoms of SARS-CoV-2 infection and long-COVID-19. The present prospective observational study aimed to evaluate the efficacy of olfactory training (OT) on orthonasal and retronasal olfactory function in a cohort of individuals with persistent post-COVID-19 OL. Participants with post-COVID-19 olfactory impairment underwent 4 months of OT, self-assessing their smell perception and undergoing comprehensive psychophysical evaluation of orthonasal and retronasal olfaction at baseline and after training. Orthonasal olfactory function was assessed using the extended Sniffin' Sticks test battery. Retronasal olfactory function was tested with powdered aromas. Among 114 participants with post-COVID-19 olfactory loss, adherence to OT was 60%. In adherents, the average increase in composite TDI score was 6.0 points compared to 2.6 points in non-adherents. Fifty-seven percent of adherent participants achieved a clinically significant improvement in TDI score (≥ 5.5 points), compared to 22% of non-adherents. In retronasal olfactory identification, 56% of adherents achieved a clinically significant improvement (≥4 points), compared to 16% of non-adherents. Adherence to a 4-month OT regimen can yield clinically meaningful improvements in both orthonasal and retronasal olfactory function among individuals with persistent post-COVID-19 olfactory dysfunction.