The influence of predator odours and overcrowded mouse odours on regulation of oestrous cycles in house mice (\u3ci\u3eMus musculus\u3c/i\u3e)

We investigated the influence of chemical signals derived from different sources—urine of feral cats (Felis catus) and urine from overcrowded mice (Mus musculus) on regulation of oestrous cycles in Mus musculus musculus under laboratory conditions. Cat urine and urine from mice housed in overcrowded conditions caused very similar effects. Application of urine from feral cats and from overcrowded conspecifics to the bedding of experimental animals for a period of 21 days caused a significant increase in numbers of animals with extended oestrous cycles. Application of cat urine or overcrowded mouse urine to the bedding of female mice caused an extension of oestrous cycles in 56.0% and 62.5% of tested animals, respectively. The results of the present study and other experimental data from our laboratory may indicate that predator urine and urine from overcrowded conspecifics share the same chemical information

Predator presence affects the reproductive success of prey in outdoor conditions

The reproductive outcomes of laboratory rats (Rattus norvegicus) housed at different distances (2, 20 and 80 m) from a predator (Lynx lynx) were investigated. Virgin female (n = 120) and m3ie (n = 40) rats of an outbred laboratory population were used for the experiments. Groups of rats (one male and three females) were housed in standard cages in close proximity to the predator Litter size, sex ratio. number of live pups, number of placental scars and corpora lurea were counted; and pre- and post-implantation losses were calculated for each female. The reproductive success of females, estimated as the number of live pups per female, was significantly higher in both control groups (20 and 80 m) than in both experimental Eraups (2 and 2 m). Equal numbers of corpora lutea in all groups but different numbers of placental scars between control and experimental groups indicated higher pre-implantation losses in the experimental groups. Post-implantation losses were also higher in both experimental groups. Total losses (calculated as a difference between the number of corpora lutea and live pups) were twice as high in experimental groups. Reproductive success of rats depended on concentrate/intensity of predator scents: when concentration/intensity was higher, the number of live pups was less and the total loss was higher

Roles of the main olfactory and vomeronasal systems in the detection of androstenone in inbred strains of mice

We investigated the role of the main olfactory and accessory olfactory systems (MOS and AOS respectively) in the detection of androstenone. We used the following experimental approaches: behavioral, surgical removal of the vomeronasal organ (VNX) followed by histochemical verification and Fos immunohistochemistry. Using a Y-maze paradigm we estimated sensitivity of NZB/B1NJ and CBA/J mice to androstenone. CBA mice were 2,000-fold more sensitive to androstenone than NZB mice. VNX caused a 4- to16-fold decrease in sensitivity to androstenone in highly-sensitive CBA mice, but did not affect thresholds in NZB mice. Results indicate the involvement of the MOS and AOS in the detection of androstenone. We observed a specific pattern of Fos-positive cells in the main olfactory bulb of CBA mice but not in NZB mice subsequent to exposure of mice to androstenone; the compound activated cells in the accessory olfactory bulb in both strains of mice, indicating the involvement of the vomeronasal organ. Patterns of Fos-positive cells in the vomeronasal organ were recorded subsequent to exposure to androstenone. Fos-positive receptor cells in the vomeronasal organ of CBA and NZB mice were different, in CBA mice Fos-positive cells were noted in both the basal and apical zones, however, in NZB mice activation was observed only in the apical zone [Current Zoology 56 (6): 813–818, 2010]

Predator odours as reproductive inhibitors for Norway rats

We examined the influence of predator odor on reproductive output of Norway rats (Rattus norvegicus). Naive laboratory rats responded to predator chemical cues with reduced litter sire and skewed sex ratio. We found that exposure to predator urine had its greatest effect on implantation and maintenance of implantation when predator urine was applied to the bedding of rats during the first third of gestation. Based on the physical appearance of corpora lutea and uterine implantation scars, we found that the reduction in litter sire was due to resolution of the embryos during the early part of gestation. Subsequently, we discovered that the reduction in litter sizes in rats exposed to predator urine could be attributed to suppressed progesterone levels affecting implantation of embryos. Chronically high corticoslerone levels did not suppress reproductive output. Suppression of reproduction also occurred when rats were exposed to urine of conspecifics housed under high population densities. The evolutionary adaptive response for reduced litter sire is to produce high-quality offspring in an environment where food resources are scarce. The fact that rats respond to certain chemical signals in predator urine in a similar fashion may be fortuitous, and may have more to do with the coincidence that the urine contains similar cues resulting from protein digestion in carnivores and protein catabolism in nutritionally deprived rodents, rather than specific predator-prey adaptations

Dataset on assessing olfactory function in the residents of Central Russia using the University of Pennsylvania Smell Identification Test

Data were acquired via sensory testing of olfactory function in 252 adult residents of Central Russia (18–87 years old), including groups from urban and rural areas. The 40-item North American version of the University of Pennsylvania Smell Identification Test (UPSIT) was used. The test alternatives were initially translated into Russian by the authors with minor adaptations. We followed the test procedure recommended by the manufacturer and introduced additional tasks. Familiarity with odor names and consistency with the pre-existing concepts for the test odor items were determined using multiple response questions. Intensity ratings for the UPSIT odorants were obtained using 4-point categorical scale for a subset of the participants. Demographic data and other relevant characteristics of the study population were collected using an adapted translation of the questionnaire included with the test. Descriptive statistics of the collected data are presented in this article. The dataset may be reused for evaluating the impact of various factors, such as cultural context, age, sex, environment, and smoking habits, on the perception of specific odorants as well as on general olfactory function (determined by the number of recognized test items). The data may find its application in the clinical practice of otolaryngologists and neurologists who work with the ethno-cultural group in Russia and all over the world. The dataset can also be used for development of new diagnostic tools for olfactory dysfunction

Possible roles of phytochemicals with bioactive properties in the prevention of and recovery from COVID-19

There have been large geographical differences in the infection and death rates of COVID-19. Foods and beverages containing high amounts of phytochemicals with bioactive properties were suggested to prevent contracting and to facilitate recovery from COVID-19. The goal of our study was to determine the correlation of the type of foods/beverages people consumed and the risk reduction of contracting COVID-19 and the recovery from COVID-19.The author(s) declare that financial support was received for the research, authorship, and/or publication of this article. PJ was supported by the National Institute of Alcohol Abuse and Alcoholism under award number, Z01AA000135, the National Institute of Nursing Research and the Rockefeller University Heilbrunn Nurse Scholar Award. PJ was supported by the Office of Workforce Diversity, National Institutes of Health Distinguished Scholar Program. KC was funded by NSF DGE-1839285.info:eu-repo/semantics/publishedVersio

Possible roles of phytochemicals with bioactive properties in the prevention of and recovery from COVID-19

IntroductionThere have been large geographical differences in the infection and death rates of COVID-19. Foods and beverages containing high amounts of phytochemicals with bioactive properties were suggested to prevent contracting and to facilitate recovery from COVID-19. The goal of our study was to determine the correlation of the type of foods/beverages people consumed and the risk reduction of contracting COVID-19 and the recovery from COVID-19.MethodsWe developed an online survey that asked the participants whether they contracted COVID-19, their symptoms, time to recover, and their frequency of eating various types of foods/beverages. The survey was developed in 10 different languages.ResultsThe participants who did not contract COVID-19 consumed vegetables, herbs/spices, and fermented foods/beverages significantly more than the participants who contracted COVID-19. Among the six countries (India/Iran/Italy/Japan/Russia/Spain) with over 100 participants and high correspondence between the location of the participants and the language of the survey, in India and Japan the people who contracted COVID-19 showed significantly shorter recovery time, and greater daily intake of vegetables, herbs/spices, and fermented foods/beverages was associated with faster recovery.ConclusionsOur results suggest that phytochemical compounds included in the vegetables may have contributed in not only preventing contraction of COVID-19, but also accelerating their recovery

Recent Smell Loss Is the Best Predictor of COVID-19 Among Individuals With Recent Respiratory Symptoms.

In a preregistered, cross-sectional study, we investigated whether olfactory loss is a reliable predictor of COVID-19 using a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0-100 visual analog scales (VAS) for participants reporting a positive (C19+; n = 4148) or negative (C19-; n = 546) COVID-19 laboratory test outcome. Logistic regression models identified univariate and multivariate predictors of COVID-19 status and post-COVID-19 olfactory recovery. Both C19+ and C19- groups exhibited smell loss, but it was significantly larger in C19+ participants (mean ± SD, C19+: -82.5 ± 27.2 points; C19-: -59.8 ± 37.7). Smell loss during illness was the best predictor of COVID-19 in both univariate and multivariate models (ROC AUC = 0.72). Additional variables provide negligible model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms (e.g., fever). Olfactory recovery within 40 days of respiratory symptom onset was reported for ~50% of participants and was best predicted by time since respiratory symptom onset. We find that quantified smell loss is the best predictor of COVID-19 amongst those with symptoms of respiratory illness. To aid clinicians and contact tracers in identifying individuals with a high likelihood of having COVID-19, we propose a novel 0-10 scale to screen for recent olfactory loss, the ODoR-19. We find that numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (4 < OR < 10). Once independently validated, this tool could be deployed when viral lab tests are impractical or unavailable

Corrigendum to::More Than Smell-COVID-19 Is Associated with Severe Impairment of Smell, Taste, and Chemesthesis (Chemical Senses (2020) DOI: 10.1093/chemse/bjaa041)

This is a correction notice for article bjaa041 (DOI: https:// doi.org/10.1093/chemse/bjaa041), published 20 June 2020. An incorrect version of the caption to Figure 5 was mistakenly included in the published paper. An updated version is given below. Neither the data nor the paper's conclusions were affected by this correction. The authors sincerely apologize for the error. (A) Correlations between the 3 principal components with respect to changes in 3 chemosensory modalities (i.e., taste, smell, and chemesthesis). Shades of gray indicate positive correlation, whereas shades of red indicate negative correlations. White denotes no correlation. (B) Clusters of participants identified by k-means clustering. The scatterplot shows each participant's loading on dimension 1 (degree of smell and taste loss, PC1 on x-Axis) and dimension 2 (degree of chemesthesis loss, PC2 on y-Axis). Based on the centroid of each cluster, participants in cluster 1 (blue, N = 1767; top left) are generally characterized by significant smell, taste and chemesthesis loss. Participants in cluster 2 (orange, N = 1724; bottom center) are generally characterized by ratings that reflect smell/taste loss with preserved chemesthesis. Loadings for participants in cluster 3 (green, N = 548; right side) are generally characterized by reduced smell and taste loss, and preserved chemesthesis

The best COVID-19 predictor is recent smell loss: a cross-sectional study

Background: COVID-19 has heterogeneous manifestations, though one of the most common symptoms is a sudden loss of smell (anosmia or hyposmia). We investigated whether olfactory loss is a reliable predictor of COVID-19. Methods: This preregistered, cross-sectional study used a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0-100 visual analog scales (VAS) for participants reporting a positive (C19+; n=4148) or negative (C19-; n=546) COVID-19 laboratory test outcome. Logistic regression models identified singular and cumulative predictors of COVID-19 status and post-COVID-19 olfactory recovery. Results: Both C19+ and C19- groups exhibited smell loss, but it was significantly larger in C19+ participants (mean±SD, C19+: -82.5±27.2 points; C19-: -59.8±37.7). Smell loss during illness was the best predictor of COVID-19 in both single and cumulative feature models (ROC AUC=0.72), with additional features providing no significant model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms, such as fever or cough. Olfactory recovery within 40 days was reported for ~50% of participants and was best predicted by time since illness onset. Conclusions: As smell loss is the best predictor of COVID-19, we developed the ODoR-19 tool, a 0-10 scale to screen for recent olfactory loss. Numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (10<OR<4), especially when viral lab tests are impractical or unavailable