scholarly journals African Gene Flow Reduces Beta-Ionone Anosmia/Hyposmia Prevalence in Admixed Malagasy Populations

2021 ◽  
Vol 11 (11) ◽  
pp. 1405
Author(s):  
Harilanto Razafindrazaka ◽  
Veronica Pereda-Loth ◽  
Camille Ferdenzi ◽  
Margit Heiske ◽  
Omar Alva ◽  
...  

While recent advances in genetics make it possible to follow the genetic exchanges between populations and their phenotypic consequences, the impact of the genetic exchanges on the sensory perception of populations has yet to be explored. From this perspective, the present study investigated the consequences of African gene flow on odor perception in a Malagasy population with a predominantly East Asian genetic background. To this end, we combined psychophysical tests with genotype data of 235 individuals who were asked to smell the odorant molecule beta-ionone (βI). Results showed that in this population the ancestry of the OR5A1 gene significantly influences the ability to detect βI. At the individual level, African ancestry significantly protects against specific anosmia/hyposmia due to the higher frequency of the functional gene (OR ratios = 14, CI: 1.8–110, p-value = 0.012). At the population level, African introgression decreased the prevalence of specific anosmia/hyposmia to this odorous compound. Taken together, these findings validate the conjecture that in addition to cultural exchanges, genetic transfer may also influence the sensory perception of the population in contact.

Diagnostics ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 361
Author(s):  
Leo Kilian ◽  
Philipp Krisai ◽  
Thenral Socrates ◽  
Christian Arranto ◽  
Otmar Pfister ◽  
...  

Background: The Somnotouch-Non-Invasive-Blood-Pressure (NIBP) device delivers raw data consisting of electrocardiography and photoplethysmography for estimating blood pressure (BP) over 24 h using pulse-transit-time. The study’s aim was to analyze the impact on 24-hour BP results when processing raw data by two different software solutions delivered with the device. Methods: We used data from 234 participants. The Somnotouch-NIBP measurements were analyzed using the Domino-light and Schiller software and compared. BP values differing >5 mmHg were regarded as relevant and explored for their impact on BP classification (normotension vs. hypertension). Results: Mean (±standard deviation) absolute systolic/diastolic differences for 24-hour mean BP were 1.5 (±1.7)/1.1 (±1.3) mm Hg. Besides awake systolic BP (p = 0.022), there were no statistically significant differences in systolic/diastolic 24-hour mean, awake, and asleep BP. Twenty four-hour mean BP agreement (number (%)) between the software solutions within 5, 10, and 15 mmHg were 222 (94.8%), 231 (98.7%), 234 (100%) for systolic and 228 (97.4%), 232 (99.1%), 233 (99.5%) for diastolic measurements, respectively. A BP difference of >5 mmHg was present in 24 (10.3%) participants leading to discordant classification in 4–17%. Conclusion: By comparing the two software solutions, differences in BP are negligible at the population level. However, at the individual level there are, in a minority of cases, differences that lead to different BP classifications, which can influence the therapeutic decision.


2020 ◽  
Vol 47 (2) ◽  
pp. 224-234
Author(s):  
Charlotte Probst ◽  
Tuong Manh Vu ◽  
Joshua M. Epstein ◽  
Alexandra E. Nielsen ◽  
Charlotte Buckley ◽  
...  

Background. By defining what is “normal,” appropriate, expected, and unacceptable, social norms shape human behavior. However, the individual-level mechanisms through which social norms impact population-level trends in health-relevant behaviors are not well understood. Aims. To test the ability of social norms mechanisms to predict changes in population-level drinking patterns. Method. An individual-level model was developed to simulate dynamic normative mechanisms and behavioral rules underlying drinking behavior over time. The model encompassed descriptive and injunctive drinking norms and their impact on frequency and quantity of alcohol use. A microsynthesis initialized in 1979 was used as a demographically representative synthetic U.S. population. Three experiments were performed in order to test the modelled normative mechanisms. Results. Overall, the experiments showed limited influence of normative interventions on population-level alcohol use. An increase in the desire to drink led to the most meaningful changes in the population’s drinking behavior. The findings of the experiments underline the importance of autonomy, that is, the degree to which an individual is susceptible to normative influence. Conclusion. The model was able to predict theoretically plausible changes in drinking patterns at the population level through the impact of social mechanisms. Future applications of the model could be used to plan norms interventions pertaining to alcohol use as well as other health behaviors.


2021 ◽  
Author(s):  
Fernando A Villanea ◽  
Kelsey E Witt ◽  
Elle Loughran ◽  
Emilia A Huerta-Sanchez

The apportionment of human genetic diversity within and between populations has been measured to understand human relatedness and demographic history. Likewise, the distribution of archaic ancestry in modern populations can be leveraged to better understand the interaction between our species and its archaic relatives, and the impact of natural selection on archaic segments of the human genome. Resolving these interactions can be difficult, as archaic variants in modern populations have also been shaped by genetic drift, bottlenecks, and gene flow. Here, we investigate the apportionment of archaic variation in Eurasian populations. We find that archaic genome coverage at the individual- and population-level present unique patterns in modern human population: South Asians have an elevated count of population-unique archaic SNPs, and Europeans and East Asians have a higher degree of archaic SNP sharing, indicating that population demography and archaic admixture events had distinct effects in these populations. We confirm previous observations that East Asians have more Neanderthal ancestry than Europeans at an individual level, but surprisingly Europeans have more Neandertal ancestry at a population level. In comparing these results to our simulated models, we conclude that these patterns likely reflect a complex series of interactions between modern humans and archaic populations.


Crisis ◽  
2020 ◽  
pp. 1-7 ◽  
Author(s):  
Paul S. F. Yip ◽  
Yan Zheng

Abstract. Background: In Hong Kong, there have been significant changes in suicide rates during the period 1996–2015. Aim: We aimed to assess the impact of change in suicide rates on life expectancy in Hong Kong. Method: A decomposition method was used to quantify the impact of suicide on life expectancy in Hong Kong. Results: During 1996–2003, the increase in total suicide rate made negative contributions to the increase in life expectancy in Hong Kong (−0.15 years), with incidence component and age component accounting for −0.17 years and 0.02 years, respectively. However, during 2003–2015, the decrease in the number of suicide deaths contributed to the life expectancy by 0.16 years, with the incidence component still playing a predominant role. Furthermore, the contribution mechanism of suicide varied across suicide methods and gender. Limitations: Apart from suicide, the change in life expectancy could be affected by various factors, which needs to be considered. Moreover, conclusions of the study were made at the population level rather than the individual level. Conclusion: Suicide has a non-negligible impact on life expectancy in Hong Kong. Understanding the contribution pattern of suicide and sustaining effective strategies for suicide intervention would contribute positively to improvements in Hong Kong life expectancy.


2011 ◽  
Vol 8 (63) ◽  
pp. 1510-1520 ◽  
Author(s):  
H. L. Mills ◽  
T. Cohen ◽  
C. Colijn

Individuals living with HIV experience a much higher risk of progression from latent M. tuberculosis infection to active tuberculosis (TB) disease relative to individuals with intact immune systems. A several-month daily course of a single drug during latent infection (i.e. isoniazid preventive therapy (IPT)) has proved in clinical trials to substantially reduce an HIV-infected individual's risk of TB disease. As a result of these findings and ongoing studies, the World Health Organization has produced strong guidelines for implementing IPT on a community-wide scale for individuals with HIV at risk of TB disease. To date, there has been limited use of IPT at a community-wide level. In this paper, we present a new co-network model for HIV and TB co-epidemics to address questions about how the population-level impact of community-wide IPT may differ from the individual-level impact of IPT offered to selected individuals. In particular, we examine how the effect of clustering of contacts within high-TB incidence communities may affect the rates of re-infection with TB and how this clustering modifies the expected population-level effects of IPT. We find that populations with clustering of respiratory contacts experience aggregation of TB cases and high numbers of re-infection events. While, encouragingly, the overall population-level effects of community-wide IPT appear to be sustained regardless of network structure, we find that in populations where these contacts are highly clustered, there is dramatic heterogeneity in the impact of IPT: in some sub-regions of these populations, TB is nearly eliminated, while in others, repeated re-infection almost completely undermines the effect of IPT. Our findings imply that as IPT programmes are brought to scale, we should expect local heterogeneity of effectiveness as a result of the complex patterns of disease transmission within communities.


Open Biology ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 200138
Author(s):  
Oren Kolodny ◽  
Michael Berger ◽  
Marcus W. Feldman ◽  
Yoav Ram

The course of infection by SARS-CoV-2 frequently includes a long asymptomatic period, followed in some individuals by an immune dysregulation period that may lead to complications and immunopathology-induced death. This course of disease suggests that the virus often evades detection by the innate immune system. We suggest a novel therapeutic approach to mitigate the infection's severity, probability of complications and duration. We propose that priming an individual's innate immune system for viral attack shortly before it is expected to occur may allow pre-activation of the preferable trajectory of immune response, leading to early detection of the virus. Priming can be carried out, for example, by administering a standard vaccine or another reagent that elicits a broad anti-viral innate immune response. By the time that the expected SARS-CoV-2 infection occurs, activation cascades will have been put in motion and levels of immune factors needed to combat the infection will have been elevated. The infection would thus be cleared faster and with less complication than otherwise, alleviating adverse clinical outcomes at the individual level. Moreover, priming may also mitigate population-level risk by reducing need for hospitalizations and decreasing the infectious period of individuals, thus slowing the spread and reducing the impact of the epidemic. In view of the latter consideration, our proposal may have a significant epidemiological impact even if applied primarily to low-risk individuals, such as young adults, who often show mild symptoms or none, by shortening the period during which they unknowingly infect others. The proposed view is, at this time, an unproven hypothesis. Although supported by robust bio-medical reasoning and multiple lines of evidence, carefully designed clinical trials are necessary.


2020 ◽  
Author(s):  
Sarah Bauduin ◽  
Oksana Grente ◽  
Nina Luisa Santostasi ◽  
Paolo Ciucci ◽  
Christophe Duchamp ◽  
...  

AbstractThe occurrence of wolf populations in human-dominated landscapes is challenging worldwide because of conflicts with human activities. Modeling is an important tool to predict wolf dynamics and expansion, and help in decision making concerning management and conservation. However, some individual behaviors and pack dynamics of the wolf life cycle are still unclear to ecologists. Here we present an individual-based model (IBM) to project wolf populations while exploring the lesser-known processes of the wolf life cycle. IBMs are bottom-up models that simulate the fate of individuals interacting with each other, with population-level properties emerging from the individual-level simulations. IBMs are particularly adapted to represent social species such as the wolf that exhibits complex individual interactions. Our IBM predicts wolf demography including fine-scale individual behavior and pack dynamics based on up-to-date scientific literature. We explore four processes of the wolf life cycle whose consequences on population dynamics are still poorly understood: the pack dissolution following the loss of a breeder, the adoption of young dispersers by packs, the establishment of new packs through budding, and the different types of breeder replacement. While running different versions of the IBM to explore these processes, we also illustrate the modularity and flexibility of our model, an asset to model wolf populations experiencing different ecological and demographic conditions. The different parameterization of pack dissolution, territory establishment by budding, and breeder replacement processes influence the most the projections of wolf populations. As such, these processes require further field investigation to be better understood. The adoption process has a lesser impact on model predictions. Being coded in R to facilitate its understanding, we expect that our model will be used and further adapted by ecologists for their own specific applications.


PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0248501
Author(s):  
Girmay Tsegay Kiross ◽  
Catherine Chojenta ◽  
Daniel Barker ◽  
Deborah Loxton

Introduction People living in the same area share similar determinants of infant mortality, such as access to healthcare. The community’s prevailing norms and attitudes about health behaviours could also influence the health care decisions made by individuals. In diversified communities like Ethiopia, differences in child health outcomes might not be due to variation in individual and family characteristics alone, but also due to differences in the socioeconomic characteristics of the community where the child lives. While individual level characteristics have been examined to some extent, almost all studies into infant mortality conducted in Ethiopia have failed to consider the impact of community-level characteristics. Therefore, this study aims to identify individual and community level determinants of infant mortality in Ethiopia. Method Data from the Ethiopian Demographic and Health Survey in 2016 were used for this study. A total of 10641 live births were included in this analysis. A multi-level logistic regression analysis was used to examine both individual and community level determinants while accounting for the hierarchal structure of the data. Results Individual-level characteristics such as infant sex have a statistically significant association with infant mortality. The odds of infant death before one year was 50% higher for males than females (AOR = 1.66; 95% CI: 1.25–2.20; p-value <0.001). At the community level, infants from pastoralist areas (Somali and Afar regions) were 1.4 more likely die compared with infants living in the Agrarian area such as Amhara, Tigray, and Oromia regions; AOR = 1.44; 95% CI; 1.02–2.06; p-value = 0.039). Conclusion Individual, household and community level characteristics have a statistically significant association with infant mortality. In addition to the individual based interventions already in place, household and community-based interventions such as focusing on socially and economically disadvantaged regions in Ethiopia could help to reduce infant mortality.


2021 ◽  
Vol 10 (6) ◽  
pp. 1161
Author(s):  
Raluca Pais ◽  
Thomas Maurel

The epidemiology and the current burden of chronic liver disease are changing globally, with non-alcoholic fatty liver disease (NAFLD) becoming the most frequent cause of liver disease in close relationship with the global epidemics of obesity, type 2 diabetes and metabolic syndrome. The clinical phenotypes of NAFLD are very heterogeneous in relationship with multiple pathways involved in the disease progression. In the absence of a specific treatment for non-alcoholic steatohepatitis (NASH), it is important to understand the natural history of the disease, to identify and to optimize the control of factors that are involved in disease progression. In this paper we propose a critical analysis of factors that are involved in the progression of the liver damage and the occurrence of extra-hepatic complications (cardiovascular diseases, extra hepatic cancer) in patients with NAFLD. We also briefly discuss the impact of the heterogeneity of the clinical phenotype of NAFLD on the clinical practice globally and at the individual level.


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