Environmental determinants of malaria transmission in African villages

Background Malaria transmission is complex, involving a range of hydroclimatological, biological, and environmental processes. The high degree of non-linearity in these processes makes it difficult to predict and intervene against malaria. This study seeks both to define a minimal number of malaria transmission determinants, and to provide a theoretical basis for sustainable environmental manipulation to prevent malaria transmission. Methods Using a field-tested mechanistic malaria model, HYDREMATS, a theoretical study was conducted under hypothetical conditions. Simulations were conducted with a range of hydroclimatological and environmental conditions: temperature (t), length of wet season (T[subscript wet]), storm inter-arrival time (T[subscript int]), persistence of vector breeding pools (T[subscript on]), and distribution of houses from breeding pools and from each other (X[subscript dist] and Y[subscript dist], respectively). Based on the theoretical study, a malaria time scale, T[subscript o], and a predictive theory of malaria transmission were introduced. The performance of the predictive theory was compared against the observational malaria transmission data in West Africa. Population density was used to estimate the scale that describes the spatial distribution of houses. Results The predictive theory shows a universality in malaria endemic conditions when plotted using two newly-introduced dimension-less parameters. The projected malaria transmission potential compared well with the observation data, and the apparent differences were discussed. The results illustrate the importance of spatial aspects in malaria transmission. Conclusions The predictive theory is useful in measuring malaria transmission potential, and it can also provide guidelines on how to plan the layout of human habitats in order to prevent endemic malaria. Malaria-resistant villages can be designed by locating houses further than critical distances away from breeding pools or by removing pools within a critical distance from houses; the critical distance is described in the context of local climatology and hydrology. Keywords Malaria transmission Hydrology Spatial impact Characteristic time scaleNational Science Foundation (U.S.)Masdar Institute of Science and TechnologyMassachusetts Institute of Technolog

Modelling and observing the role of wind in Anopheles population dynamics around a reservoir

Background Wind conditions, as well as other environmental conditions, are likely to influence malaria transmission through the behaviours of Anopheles mosquitoes, especially around water-resource reservoirs. Wind-induced waves in a reservoir impose mortality on aquatic-stage mosquitoes. Mosquitoes’ host-seeking activity is also influenced by wind through dispersion of CO₂. However, no malaria transmission model exists to date that simulated those impacts of wind mechanistically. Methods A modelling framework for simulating the three important effects of wind on the behaviours of mosquito is developed: attraction of adult mosquitoes through dispersion of CO₂ (CO₂ attraction), advection of adult mosquitoes (advection), and aquatic-stage mortality due to wind-induced surface waves (waves). The framework was incorporated in a mechanistic malaria transmission simulator, HYDREMATS. The performance of the extended simulator was compared with the observed population dynamics of the Anopheles mosquitoes at a village adjacent to the Koka Reservoir in Ethiopia. Results The observed population dynamics of the Anopheles mosquitoes were reproduced with some reasonable accuracy in HYDREMATS that includes the representation of the wind effects. HYDREMATS without the wind model failed to do so. Offshore wind explained the increase in Anopheles population that cannot be expected from other environmental conditions alone. Conclusions Around large water bodies such as reservoirs, the role of wind in the dynamics of Anopheles population, hence in malaria transmission, can be significant. Modelling the impacts of wind on the behaviours of Anopheles mosquitoes aids in reproducing the seasonality of malaria transmission and in estimation of the risk of malaria around reservoirs. Keywords: Malaria transmission; Water-resource reservoirs; Environmental conditionsNational Science Foundation (U.S.) (Grant EAR-0946280

Environmental determinants of malaria transmission in African villages

Background Malaria transmission is complex, involving a range of hydroclimatological, biological, and environmental processes. The high degree of non-linearity in these processes makes it difficult to predict and intervene against malaria. This study seeks both to define a minimal number of malaria transmission determinants, and to provide a theoretical basis for sustainable environmental manipulation to prevent malaria transmission. Methods Using a field-tested mechanistic malaria model, HYDREMATS, a theoretical study was conducted under hypothetical conditions. Simulations were conducted with a range of hydroclimatological and environmental conditions: temperature (t), length of wet season (Twet), storm inter-arrival time (Tint), persistence of vector breeding pools (Ton), and distribution of houses from breeding pools and from each other (Xdist and Ydist, respectively). Based on the theoretical study, a malaria time scale, To, and a predictive theory of malaria transmission were introduced. The performance of the predictive theory was compared against the observational malaria transmission data in West Africa. Population density was used to estimate the scale that describes the spatial distribution of houses. Results The predictive theory shows a universality in malaria endemic conditions when plotted using two newly-introduced dimension-less parameters. The projected malaria transmission potential compared well with the observation data, and the apparent differences were discussed. The results illustrate the importance of spatial aspects in malaria transmission. Conclusions The predictive theory is useful in measuring malaria transmission potential, and it can also provide guidelines on how to plan the layout of human habitats in order to prevent endemic malaria. Malaria-resistant villages can be designed by locating houses further than critical distances away from breeding pools or by removing pools within a critical distance from houses; the critical distance is described in the context of local climatology and hydrology. Keywords: Malaria transmission; Hydrology; Spatial impact; Characteristic time scal

Wind: a neglected factor in the spread of infectious diseases – Authors' reply

We thank Joel Ellwanger and José Chies for their Correspondence regarding our Article. This Correspondence resonates with theirs and highlights a neglected approach in One Health from a larger perspective. After unprecedented momentum and success in global malaria control in the first decade of 21st century, progress appears to have stalled.1 The easier goals have been achieved, but the remaining challenges require more sustainable and substantial investment in health-related infrastructure in resource-limited countries

The Inhibitory Effect of Conjugated and Polyunsaturated Fatty Acids on the Growth of Human Cancer Cell Lines

arachidonic acidconjugated fatty acidcytotoxicitydocosahexaenoic acideicosapentaenoic acidhuman cancer cerllpolyunsaturated fatty aci

Factors associated with enrollment and adherence of outpatient cardiac rehabilitation in Japan

博士（医学）福島県立医科大

Advanced Java-based application to process thermoluminescence digital color images

Dielectric minerals that interact with ionizing radiation emit thermoluminescence when heated. The color of the emitted thermoluminescence varies among different samples, even for the same minerals. TL color analysis can be used to study mineral provenance. Thermoluminescence color images (TLCI) can be obtained using a digital camera. Inagaki et al. (2010) created a Java application to handle RGB (red-green-blue) information of each pixel. This Java application is able to visually represent thermoluminescence color on a CIE (Commission Internationale de l’Eclairage) chromaticity diagram. Here, we report an improved Java application that enables the numerical treatment of TLCI of various image sizes and resolutions. This application allows for the handling of many digital TLCI in a short time and it is useful for statistical color analyses

Frequent Mutations in the β-Catenin Gene in Cholangiocarcinoma

The molecular pathogenesis of cholangiocarcinoma (CC) remains unclear. β-Catenin functions in both intercellular adhesion and signal transduction. As a signaling molecule, mutations in exon 3 of the β-catenin gene encoding the regions phosphorylated by glycogen synthase kinase (GSK)-3β stabilize this protein in cytoplasm. Subsequently, accumulated β-catenin protein translocates to nuclei and up-regulates the transcriptional activity of genes involved in oncogenesis. Recently, mutations in exon 3 of the β-catenin gene were detected in various carcinomas. Using polymerase chain reaction (PCR)-single-strand conformational polymorphism (SSCP) analysis, direct sequencing and subcloning-sequencing, we investigated mutations of exon 3 of the β-catenin gene in CC. Mutations were found in 26 out of 33 (78.8%) CC tumor samples. All of the mutations were heterozygous 1-base deletions at codon 15, resulting in a stop codon at codon 46. This is the first study demonstrating the presence of β-catenin gene mutations in CC. However, it was suggested that this mutation might not be involved in deregulation of β-catenin signaling, because no correlation was observed between the β-catenin mutation and immunolocalization of β-catenin protein

Analysis of 39 drugs and metabolites, including 8 glucuronide conjugates, in an upstream wastewater network via HPLC-MS/MS

© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Foppe, K. S., Kujawinski, E. B., Duvallet, C., Endo, N., Erickson, T. B., Chai, P. R., & Matus, M. Analysis of 39 drugs and metabolites, including 8 glucuronide conjugates, in an upstream wastewater network via HPLC-MS/MS. Journal of Chromatography B, 1176, (2021): 122747, https://doi.org/10.1016/j.jchromb.2021.122747.Pharmaceutical compounds ingested by humans are metabolized and excreted in urine and feces. These metabolites can be quantified in wastewater networks using wastewater-based epidemiology (WBE) methods. Standard WBE methods focus on samples collected at wastewater treatment plants (WWTPs). However, these methods do not capture more labile classes of metabolites such as glucuronide conjugates, products of the major phase II metabolic pathway for drug elimination. By shifting sample collection more upstream, these unambiguous markers of human exposure are captured before hydrolysis in the wastewater network. In this paper, we present an HPLC-MS/MS method that quantifies 8 glucuronide conjugates in addition to 31 parent and other metabolites of prescription and synthetic opioids, overdose treatment drugs, illicit drugs, and population markers. Calibration curves for all analytes are linear (r2 > 0.98), except THC (r2 = 0.97), and in the targeted range (0.1–1,000 ng mL−1) with lower limits of quantification (S/N = 9) ranging from 0.098 to 48.75 ng mL−1. This method is fast with an injection-to-injection time of 7.5 min. We demonstrate the application of the method to five wastewater samples collected from a manhole in a city in eastern Massachusetts. Collected wastewater samples were filtered and extracted via solid-phase extraction (SPE). The SPE cartridges are eluted and concentrated in the laboratory via nitrogen-drying. The method and case study presented here demonstrate the potential and application of expanding WBE to monitoring labile metabolites in upstream wastewaterThis work was supported by the National Institute on Drug Abuse of the National Institutes of Health award number R44DA051106 to MM and PC. TE, PC and MM are funded by research grants from the Massachusetts Consortium on Pathogen Readiness and NIH R44DA051106. PRC is funded by NIH K23DA044874, independent research grants from e-ink corporation and Hans and Mavis Lopater Psychosocial Foundation