The transition from a rural to an urban environment alters expression of the human Ebola virus receptor Neiman-Pick C1: implications for the current epidemic in West Africa

Measurement and Spatial Differentiation of Farmers' Livelihood Resilience Under the COVID-19 Epidemic Outbreak in Rural China

Livelihood resilience is the ability of individuals, families or communities to withstand external shocks based on existing resources. It is an important research paradigm in sustainable development studies. The outbreak of COVID-19 and strict epidemic prevention policies have greatly impacted the production and life of rural farmers in China. The resilience of farmers' livelihoods during the epidemic is crucial to the sustainable development of their livelihoods and regional stability. This study uses classic buffer capacity, self-organization ability, and the capacity for learning a three-dimension livelihood resilience framework using the comprehensive index, OLS, and geographical detector methods based on Hubei province and neighboring Anhui and Chongqing. Rural household survey data investigate the background of epidemic hit the livelihood of farmers resilience and its spatial distribution pattern and identify the key influencing factors. The results show that the livelihood shock faced by farmers was higher than the risk of disease, and the overall level of livelihood resilience was low after the pandemic. Financial capital and social capital can effectively help farmers to eliminate livelihood difficulties. In contrast, natural capital has a limited driving force, and physical and human capital have no obvious impact. The spatial agglomeration differentiation is obvious, indicating that the impact of COVID-19 on livelihoods was closely related to the degree of local socio-economic development and geographical location. The results of this study provide targeted recommendations for the development of epidemic prevention and livelihood resilience policies tailored to local conditions, emphasizing the importance of boosting livelihood recovery at both the government and household levels.

Differential expression of nuclear genes encoding mitochondrial proteins from urban and rural populations in Morocco

Urbanization in low-income countries represents an important inflection point in the epidemiology of disease, with rural populations experiencing high rates of chronic and recurrent infections and urban populations displaying a profile of noncommunicable diseases. To investigate if urbanization alters the expression of genes encoding mitochondrial proteins, we queried gene microarray data from rural and urban populations living in Morocco (GSE17065). The R Bioconductor packages edgeR and limma were used to identify genes with different expression. The experimental design was modeled upon location and sex. Nuclear genes encoding mitochondrial proteins were identified from the MitoCarta2.0 database. Of the 1158 genes listed in the MitoCarta2.0 database, 847 genes (73%) were available for analysis in the Moroccan dataset. The urban-rural comparison with the greatest environmental differences showed that 76.5% of the MitoCarta2.0 genes were differentially expressed, with 97% of the genes having an increased expression in the urban area. Enrichment analysis revealed 367 significantly enriched pathways (adjusted p value < 0.05), with oxidative phosphorylation, insulin secretion and glucose regulations (adj.p values = 6.93E-16) being the top three. Four significantly perturbed KEGG disease pathways were associated with urbanization-three degenerative neurological diseases (Huntington's, Alzheimer's, and Parkinson's diseases) and herpes simplex infection (false discover rate corrected p value (PGFdr) < 0.2). Mitochondrial RNA metabolic processing and translational elongation were the biological processes that had the greatest enrichment (enrichment ratios 14.0 and 14.8, respectively, FDR < 0.5). Our study links urbanization in Morocco with changes in the expression of the nuclear genes encoding mitochondrial proteins.

Urbanization in Sub-Saharan Africa: Declining Rates of Chronic and Recurrent Infection and Their Possible Role in the Origins of Non-communicable Diseases

BACKGROUND

Non-communicable diseases (NCDs), such as atherosclerosis and cancers, are a leading cause of death worldwide. An important, yet poorly explained epidemiological feature of NCDs is their low incidence in under developed areas of low-income countries and rising rates in urban areas.

METHODS

With the goal of better understanding how urbanization increases the incidence of NCDs, we provide an overview of the urbanization process in sub-Saharan Africa, discuss gene expression differences between rural and urban populations, and review the current NCD determinant model. We conclude by identifying research priorities.

RESULTS

Declining rates of chronic and recurrent infection are the hallmark of urbanization in sub-Saharan Africa. Gene profiling studies show urbanization results in complex molecular changes, with almost one-third of the peripheral blood leukocyte transcriptome altered. The current NCD determinant model could be improved by including a possible effect from declining rates of infection and expanding the spectrum of diseases that increase with urbanization.

CONCLUSIONS

Urbanization in sub-Saharan Africa provides a unique opportunity to investigate the mechanism by which the environment influences disease epidemiology. Research priorities include: (1) studies to define the relationship between infection and risk factors for NCDs, (2) explaining the observed differences in the inflammatory response between rural and urban populations, and (3) identification of animal models that simulate the biological changes that occurs with urbanization. A better understanding of the biological changes that occur with urbanization could lead to new prevention and treatment strategies for some of the most common surgical diseases in high-income countries.

Out of Africa: Insights from a prospective pediatric surgery database

In this year's Robert E. Gross lecture, I describe how experiences early in my career at a government referral hospital in Banjul, The Gambia, influenced my research. Collecting prospective data on all children presenting to the hospital with surgical problems allowed me to gain an understanding of the epidemiology of childhood surgical conditions in sub-Saharan Africa and an appreciation for the inherent challenges of delivering surgical care in settings of limited resources. Based on findings from this database, my research over the past 20years has focused on developing strategies for improving surgical care in low-income countries and better understanding the geographical variations that occur in some of the most common surgical conditions in high-income countries (e.g., appendicitis). Although this research continues to be a work-in-progress, it has the potential to improve the surgical care of children in both high- and low-income countries. Much of this research would not have been possible had I not ventured off the usual path for an academic surgeon.

The transition from a rural to an urban environment in Africa alters G protein-coupled receptor signaling

Urbanization in Africa is associated with an increased incidence of non-communicable diseases, yet the cause and the mechanism remain poorly understood. Here, we propose a role for G protein-coupled receptor (GPCR) signaling in the biological changes that occur with urbanization and suggest a critical area of convergence in GPCR signaling might provide a molecular signature for exposure to environmental factors. As a first step in investing this hypothesis, we examined the expression of the G protein α, β and γ subunit, G protein related kinase, and β-arrestin genes in a rural and urban population living in Morocco (NCBI GSE8847). Three genes associated with the phosphatidylinositol signaling pathway (GNAQ, GNA11 and GNA15), and one gene controlling the cyclic adenosine monophosphate pathway (GNAI2) was altered by urbanization. Of note, the expression of ARRB1 gene, which encodes the β-arrestin 1 protein and dampens the cellular responses to extracellular signals, was greater in the rural compared to the urban population (P<0.00002). These preliminary findings support our hypothesis that urbanization fundamentally alters GPCR signaling, resulting in both a qualitative and quantitative change in the signaling process. Because GPCR signaling is involved in a broad spectrum of cellular functions, further research is needed confirm these preliminary findings and to investigate what role GPCRs might have in the biological changes that occur with urbanization.