Search

While conducting a review of published archaeobotanical remains from southern and central England, it became apparent that contamination (intrusion and residuality) was a notable, recurring theme in many assemblages. This problem is most acute in some key periods in which plant assemblages are generally less abundant than in others, such as the Neolithic and the early medieval (Saxon) periods. While most archaeobotanists are aware of the potential for contamination, without direct dates it is often difficult to demonstrate and it is likely to have obscured the true patterns in the data. Contamination becomes particularly problematic once poorly or incorrectly phased data enter the secondary literature. A number of case studies are presented, including newly dated material from a high profile excavation at Durrington Walls, Wiltshire. The importance of direct dating of plant remains is discussed. [ABSTRACT FROM AUTHOR]

Background: The thyroid hormone triiodothyronine (T3) is known to affect energy balance. Recent evidence points to an action of T3 in the hypothalamus, a key area of the brain involved in energy homeostasis, but the components and mechanisms are far from understood. The aim of this study was to identify components in the hypothalamus that may be involved in the action of T3 on energy balance regulatory mechanisms. Methods: Sprague Dawley rats were made hypothyroid by giving 0.025% methimazole (MMI) in their drinking water for 22 days. On day 21, half the MMI-treated rats received a saline injection, whereas the others were injected with T3. Food intake and body weight measurements were taken daily. Body composition was determined by magnetic resonance imaging, gene expression was analyzed by in situ hybridization, and T3-induced gene expression was determined by microarray analysis of MMI-treated compared to MMI-T3-injected hypothalamic RNA. Results: Post mortem serum thyroid hormone levels showed that MMI treatment decreased circulating thyroid hormones and increased thyrotropin (TSH). MMI treatment decreased food intake and body weight. Body composition analysis revealed reduced lean and fat mass in thyroidectomized rats from day 14 of the experiment. MMI treatment caused a decrease in circulating triglyceride concentrations, an increase in nonesterified fatty acids, and decreased insulin levels. A glucose tolerance test showed impaired glucose clearance in the thyroidectomized animals. In the brain, in situ hybridization revealed marked changes in gene expression, including genes such as Mct8, a thyroid hormone transporter, and Agrp, a key component in energy balance regulation. Microarray analysis revealed 110 genes to be up- or downregulated with T3 treatment (±1.3-fold change, p<0.05). Three genes chosen from the differentially expressed genes were verified by in situ hybridization to be activated by T3 in cells located at or close to the hypothalamic ventricular ependymal layer and differentially expressed in animal models of long- and short-term body weight regulation. Conclusion: This study identified genes regulated by T3 in the hypothalamus, a key area of the brain involved in homeostasis and neuroendocrine functions. These include genes hitherto not known to be regulated by thyroid status. [ABSTRACT FROM AUTHOR]

Pseudobasophilia is an analyzer phenomenon whereby abnormal cells in the peripheral blood are counted as basophils. Previously described on the Technicon H-series hematology analyzers, pseudobasophilia is also a technical consideration on the Advia 120. Sometimes seen as a hindrance to inexperienced users, an understanding of the basophil (baso) method and baso cytogram produced by the Advia 120 can be utilized to alert the laboratory scientist and clinician to the possible presence of an abnormal cell population in the peripheral blood. Cytogram analysis should form part of routine laboratory practice and the present annotation aims to offer some assistance to users of the Advia 120 and Advia 2120. [ABSTRACT FROM AUTHOR]

The onset of prehistoric farming brought unprecedented changes to landscapes and their biodiversity. Past biodiversity patterns are broadly understood for different parts of Europe, and demonstrate trajectories that have been linked to prehistoric and historic demographic transitions, and associated land-use practices. To our knowledge, this paper is the first attempt to directly link evidence of agricultural practice from the archaeological record to biodiversity patterns. Records of fossil pollen are used to estimate plant and landscape diversity patterns, and novel approaches are employed to analyse 1194 harmonised archaeobotanical samples (plant macrofossil remains) spanning the prehistoric and Roman periods, from southern England. We demonstrate changes in the use of crops and gathered edible plants and non-linear trends in cultivation practices. Whilst, overall, cereal production is characterised by ever larger and extensive regimes, different trajectories are evident for most of early prehistory, the Middle Iron Age and the Late Roman period. Comparisons with the Shannon diversity of fossil pollen records from the same region suggest a positive relationship between developing agricultural regimes and landscape scale biodiversity during the prehistoric period. The Roman period represents a tipping point in the relationship between expanding agriculture and pollen diversity, with declining pollen diversity evident in the records from the region. [ABSTRACT FROM AUTHOR]

Archaeological evaluations in advance of the installation of a new garden in the area previously known as the Privy Garden, now the Princess Beatrice garden, at Carisbrooke Castle revealed the first prehistoric feature from the site and established a northern continuation of a Conquest-period ringwork ditch. The main discovery, a 12th century high status, masonry, cellared structure, probably a chamber block of two-storeys, is identified as the 'chamber next the chapel' mentioned in a 13th century account. Further structures added in the 13th-15th century are discussed. The demolition of these buildings in the late 16th century and the re-ordering of the site are seen in the context of major works by Sir George Carey. Environmental sampling, particularly of yard surfaces and a midden developed to the east and south of the chamber block, has greatly enhanced understanding of the medieval and early post-medieval diet and economy at the castle. [ABSTRACT FROM AUTHOR]

Mild dietary zinc deprivation in humans and rodents has little effect on blood plasma zinc levels, and yet cellular consequences of zinc depletion can be detected in vascular and other tissues. We proposed that a zinc-regulated humoral factor might mediate the effects of zinc deprivation. Using a novel approach, primary rat vascular smooth muscle cells (VSMCs) were treated with plasma from zinc-deficient (<1 mg Zn/kg) or zinc-adequate (35 mg Zn/kg, pair-fed) adult male rats, and zinc levels were manipulated to distinguish direct and indirect effects of plasma zinc. Gene expression changes were analyzed by microarray and qPCR, and incubation of VSMCs with blood plasma from zinc-deficient rats strongly changed the expression of > 2500 genes, compared to incubation of cells with zinc-adequate rat plasma. We demonstrated that this effect was caused by a low-molecular-weight (~2-kDa) zinc-regulated humoral factor but that changes in gene expression were mostly reversed by adding zinc back to zinc-deficient plasma. Strongly regulated genes were overrepresented in pathways associated with immune function and development. We conclude that zinc deficiency induces the production of a low-molecular-weight humoral factor whose influence on VSMC gene expression is blocked by plasma zinc. This factor is therefore under dual control by zinc. [ABSTRACT FROM AUTHOR]

Roseburia inulinivorans is a recently identified motile representative of the Firmicutes that contributes to butyrate formation from a variety of dietary polysaccharide substrates in the human large intestine. Microarray analysis was used here to investigate substrate-driven gene-expression changes in R. inulinivorans A2-194. A cluster of fructo-oligosaccharide/inulin utilization genes induced during growth on inulin included one encoding a β-fructofuranosidase protein that was prominent in the proteome of inulin-grown cells. This cluster also included a 6-phosphofructokinase and an ABC transport system, whereas a distinct inulin-induced 1-phosphofructokinase was linked to a fructose-specific phosphoenolpyruvate-dependent sugar phosphotransferase system (PTS II transport enzyme). Real-time PCR analysis showed that the β-fructofuranosidase and adjacent ABC transport protein showed greatest induction during growth on inulin, whereas the 1-phosphofructokinase enzyme and linked sugar phosphotransferase transport system were most strongly up-regulated during growth on fructose, indicating that these two clusters play distinct roles in the use of inulin. The R. inulinivorans β-fructofuranosidase was overexpressed in Escherichia coli and shown to hydrolyze fructans ranging from inulin down to sucrose, with greatest activity on fructo-oligosaccharides. Genes induced on starch included the major extracellular a-amylase and two distinct a-glucanotransferases together with a gene encoding a flagellin protein. The latter response may be concerned with improving bacterial access to insoluble starch particles. [ABSTRACT FROM AUTHOR]

Abstract: The term ‘vitrified’ is used to describe the glassy appearance of some charcoals recovered in the archaeological record. It has been generally considered that this phenomenon is a result of wood being subjected to high temperatures similar to the role of temperature in the formation of glass and pottery. Charcoals displaying characteristics of vitrification from three distinct archaeological contexts were analysed using reflectance microscopy to determine their temperature of formation. Charcoal was also generated in laboratory charring experiments at temperatures of 900–1100°C for durations of 1, 6, 12 and 24h to determine if subjection to high temperature led to vitrification. None of the laboratory-produced charcoals displayed characteristics of vitrification. Mean random reflectance of the vitrified archaeological fragments indicated temperature of formation from 310 to 530°C. A charring experiment was also conducted, at 500°C for 6h, using green wood with some bark attached, and added sugars, but no evidence of vitrification was seen. Therefore vitrified charcoals do not result from high temperature charring or primarily from the use of green wood. [ABSTRACT FROM AUTHOR]

Messenger RNA trafficking, which provides a mechanism for local protein synthesis, is dependent oncis-acting sequences in the 3′ untranslated regions (3′UTRs) of the mRNAs concerned acting together withtrans-acting proteins. The C-MYC transcription factor is a proto-oncogene product involved in cell proliferation, differentiation and apoptosis. Localization of c-mycmRNA to the perinuclear cytoplasm and its association with the cytoskeleton is determined by a signal in the 3′UTR. Here we show the specific binding of atrans-acting factor to the perinuclear localization element in the 3′UTR of c-mycmRNA and identify this protein as annexin A2. Gel retardation and UV cross-linking experiments showed that proteins in fibroblast extracts formed complexes with the region of c-myc3′UTR implicated in localization; a protein of≈ 36 kDa exhibited specific, Ca2+-dependent binding. Binding was reduced by introduction of a mutation that abrogates localization. Using RNA-affinity columns followed by gel electrophoresis and mass spectrometry this protein was identified as annexin A2. The RNA–protein complex formed by cell extracts was further retarded by anti-(annexin A2). Purified annexin A2 bound to the same region of the c-myc3′UTR but binding was reduced by introduction of a mutation, as with cell extracts. It is proposed that binding of annexin A2 to the localization signal in the c-mycmRNA leads to association with the cytoskeleton and perinuclear localization. The data indicate a novel functional role for the RNA-binding properties of annexin A2 in perinuclear localization of mRNA and the association with the cytoskeleton. [ABSTRACT FROM AUTHOR]