Short-term salivary acetaldehyde increase due to direct exposure to alcoholic beverages as an additional cancer risk factor beyond ethanol metabolism

<p>Abstract</p> <p>Background</p> <p>An increasing body of evidence now implicates acetaldehyde as a major underlying factor for the carcinogenicity of alcoholic beverages and especially for oesophageal and oral cancer. Acetaldehyde associated with alcohol consumption is regarded as 'carcinogenic to humans' (IARC Group 1), with sufficient evidence available for the oesophagus, head and neck as sites of carcinogenicity. At present, research into the mechanistic aspects of acetaldehyde-related oral cancer has been focused on salivary acetaldehyde that is formed either from ethanol metabolism in the epithelia or from microbial oxidation of ethanol by the oral microflora. This study was conducted to evaluate the role of the acetaldehyde that is found as a component of alcoholic beverages as an additional factor in the aetiology of oral cancer.</p> <p>Methods</p> <p>Salivary acetaldehyde levels were determined in the context of sensory analysis of different alcoholic beverages (beer, cider, wine, sherry, vodka, calvados, grape marc spirit, tequila, cherry spirit), without swallowing, to exclude systemic ethanol metabolism.</p> <p>Results</p> <p>The rinsing of the mouth for 30 seconds with an alcoholic beverage is able to increase salivary acetaldehyde above levels previously judged to be carcinogenic in vitro, with levels up to 1000 μM in cases of beverages with extreme acetaldehyde content. In general, the highest salivary acetaldehyde concentration was found in all cases in the saliva 30 sec after using the beverages (average 353 μM). The average concentration then decreased at the 2-min (156 μM), 5-min (76 μM) and 10-min (40 μM) sampling points. The salivary acetaldehyde concentration depends primarily on the direct ingestion of acetaldehyde contained in the beverages at the 30-sec sampling, while the influence of the metabolic formation from ethanol becomes the major factor at the 2-min sampling point.</p> <p>Conclusions</p> <p>This study offers a plausible mechanism to explain the increased risk for oral cancer associated with high acetaldehyde concentrations in certain beverages.</p

Accelerated and Improved Quantification of Lymphocytic Choriomeningitis Virus (LCMV) Titers by Flow Cytometry

Lymphocytic choriomeningitis virus (LCMV), a natural murine pathogen, is a member of the Arenavirus family, may cause atypical meningitis in humans, and has been utilized extensively as a model pathogen for the study of virus-induced disease and immune responses. Historically, viral titers have been quantified by a standard plaque assay, but for non-cytopathic viruses including LCMV this requires lengthy incubation, so results cannot be obtained rapidly. Additionally, due to specific technical constraints of the plaque assay including the visual detection format, it has an element of subjectivity along with limited sensitivity. In this study, we describe the development of a FACS-based assay that utilizes detection of LCMV nucleoprotein (NP) expression in infected cells to determine viral titers, and that exhibits several advantages over the standard plaque assay. We show that the LCMV-NP FACS assay is an objective and reproducible detection method that requires smaller sample volumes, exhibits a ∼20-fold increase in sensitivity to and produces results three times faster than the plaque assay. Importantly, when applied to models of acute and chronic LCMV infection, the LCMV-NP FACS assay revealed the presence of infectious virus in samples that were determined to be negative by plaque assay. Therefore, this technique represents an accelerated, enhanced and objective alternative method for detection of infectious LCMV that is amenable to adaptation for other viral infections as well as high throughput diagnostic platforms

Indigenous knowledges and development: a postcolonial caution

As a result of the failure of formal top-down development, there has recently been increased interest in the possibilities of drawing upon the indigenous knowledges of those in the communities involved, in an attempt to produce more effective development strategies. The concept of indigenous knowledge calls for the inclusion of local voices and priorities, and promises empowerment through ownership of the process. However, there has been little critical examination of the ways in which indigenous knowledges have been included in the development process. Drawing upon postcolonial theory, this article suggests that indigenous knowledges are often drawn into development by both theorists and development institutions in a very limited way, failing to engage with other ways of perceiving development, and thus missing the possibility of devising more challenging alternatives

Kinetic formulation and global existence for the Hall-Magneto-hydrodynamics system

This paper deals with the derivation and analysis of the the Hall Magneto-Hydrodynamic equations. We first provide a derivation of this system from a two-fluids Euler-Maxwell system for electrons and ions, through a set of scaling limits. We also propose a kinetic formulation for the Hall-MHD equations which contains as fluid closure different variants of the Hall-MHD model. Then, we prove the existence of global weak solutions for the incompressible viscous resistive Hall-MHD model. We use the particular structure of the Hall term which has zero contribution to the energy identity. Finally, we discuss particular solutions in the form of axisymmetric purely swirling magnetic fields and propose some regularization of the Hall equation

Explicit kinetic heterogeneity: mechanistic models for interpretation of labeling data of heterogeneous cell populations

Estimation of division and death rates of lymphocytes in different conditions is vital for quantitative understanding of the immune system. Deuterium, in the form of deuterated glucose or heavy water, can be used to measure rates of proliferation and death of lymphocytes in vivo. Inferring these rates from labeling and delabeling curves has been subject to considerable debate with different groups suggesting different mathematical models for that purpose. We show that the three models that are most commonly used are in fact mathematically identical and differ only in their interpretation of the estimated parameters. By extending these previous models, we here propose a more mechanistic approach for the analysis of data from deuterium labeling experiments. We construct a model of "kinetic heterogeneity" in which the total cell population consists of many sub-populations with different rates of cell turnover. In this model, for a given distribution of the rates of turnover, the predicted fraction of labeled DNA accumulated and lost can be calculated. Our model reproduces several previously made experimental observations, such as a negative correlation between the length of the labeling period and the rate at which labeled DNA is lost after label cessation. We demonstrate the reliability of the new explicit kinetic heterogeneity model by applying it to artificially generated datasets, and illustrate its usefulness by fitting experimental data. In contrast to previous models, the explicit kinetic heterogeneity model 1) provides a mechanistic way of interpreting labeling data; 2) allows for a non-exponential loss of labeled cells during delabeling, and 3) can be used to describe data with variable labeling length

Trade-offs of crop residue use in smallholder mixed farming systems in Sub-Saharan Africa and South Asia

One of the three pillars of CA is the use of crop residues (CR) for mulching. However, in smallholder farming systems that combine crop production and livestock husbandry (mixed systems), CR are usually an essential source of feed, restricting their availability for mulching. Additionally in these systems, CR fulfil other functions such as providing fuel and additional income through sale. Smallholder production in mixed systems supports the livelihoods of almost two thirds of the global population, especially in Sub-Saharan Africa and South Asia (Herrero et al., 2010). The integration between crops and animals not only enhances agricultural production, but also improves household food intake and income and provides a buffer against climate risks (Thornton, 2010). The need to cover their own food requirements and household expenses pushes smallholder farmers to favour practices with positive returns in the short term, which may affect the sustainability of the systems in the long term. Farmers‘ decisions are influenced by biophysical and socio-economic drivers including climate, population dynamics, market access and other institutional mechanisms. The focus of this paper is on the trade-offs of CR use in a range of smallholder mixed systems in Sub-Saharan Africa (SSA) and South Asia (SA). The objective of this paper is threefold: (i) to describe the different CR farmer uses in these mixed systems; (ii) to understand what biophysical and socio-economic drivers explain differences in CR allocation; and (iii) to include these findings in the broader discussion on long term sustainability issues in mixed systems and constraints for CA practices adoption

Understanding Community Perceptions of Land Use Changes in the Rangelands, Zimbabwe

The objective of this study was to investigate the user communities’ understanding and interpretation of changes in rangeland use and productivity in the communal lands of Zimbabwe. While external knowledge has been instrumental in defining the drivers and effects of ecological changes hitherto, the role of local knowledge is becoming increasingly important in explaining factors that inform user community perceptions and guide their decisions on the use of rangeland resources. Data on community perceptions were collected in four villages, using Participatory Rural Appraisals in each village and household surveys with a total of 104 households. This study showed that user communities in Nkayi district differentiate rangelands among seven categories of livestock feed resources and how these have changed over time. Communities viewed rangelands not as one continuous, designated and specialized land parcel, but differentiated the land by location, productivity, management and uses in different times of the year. Although land use changes affecting these livestock feed resources were considered to be widespread and multi-directional (both negative and positive) they did not cause widespread degradation. Rangelands converted to croplands were not completely lost, but became important dual purpose land parcels fulfilling both household food security needs and dry season livestock feed requirements. The importance of croplands as a feed resource is reflected in the emergence of new institutions governing their use for livestock grazing and to guarantee security of tenure. On the other hand institutions governing the use of common property rangelands decreased or weakened in their application. The study concludes that while this situation presents ecological challenges for the rangelands, it offers opportunities to find innovative ways of utilizing croplands as the new frontier in the provision of dry season feed resources to smallholder farmers in highly variable environments. Implications for livestock water productivity need to be investigated and water saving technologies should be promoted in the land use intensification processes

Aphrati and Kato Syme: Pottery, Continuity, and Cult in Late Archaic and Classical Crete

The analysis of ceramics from Aphrati sheds valuable new light on the history of this Cretan settlement and on its relationship with a nearby rural sanctuary at Kato Syme in the Late Archaic and Classical periods. It has long been held that Aphrati was deserted from ca. 600 to 400 B.C. A pottery deposit from the domestic quarter, however, now supports occupation of the city during this period. A ceramic classification system is presented and the morphological development and absolute chronology of several key shapes at Aphrati and Kato Syme are plotted. Historical implications of the ceramic evidence are also explored

Fully developed turbulence and the multifractal conjecture

We review the Parisi-Frisch MultiFractal formalism for Navier--Stokes turbulence with particular emphasis on the issue of statistical fluctuations of the dissipative scale. We do it for both Eulerian and Lagrangian Turbulence. We also show new results concerning the application of the formalism to the case of Shell Models for turbulence. The latter case will allow us to discuss the issue of Reynolds number dependence and the role played by vorticity and vortex filaments in real turbulent flows.Comment: Special Issue dedicated to E. Brezin and G. Paris