Lipids as carriers of anthropogenic signals from prehistory

Studies performed during the last two decades have shown that lipids are preserved in association with a wide range of artefacts and ecofacts recovered from archaeological sites, e.g. pottery vessels and skeletal remains. The majority of work in this area has focused on the use of molecular structures (''biomarkers'') and distributions (''fingerprints'') to assess the nature and origin of commodities associated with past cultural, economic and agricultural practices. However, since lipids, like all other classes of biomolecule, are affected by degradation (both pre- and post-burial), emphasis is now being placed on the complementary use of diagenetically robust, compound-specific stable isotope measurements to enhance the scope and reliability of archaeological interpretations. A feature of the δ¹³C values of individual lipids, rather than bulk measurements of biochemically more heterogeneous materials, lies in their capacity to reflect differences in both the isotopic composition of the carbon sources used in their biosynthesis and the routing of dietary lipids and their metabolites in consumer organisms. This isotopic information, accessible by gas chromatography-combustion-isotope ratio mass spectrometry, has opened up new avenues of investigation concerning human activity in prehistory.     

Hydrocarbons preserved in a ~2.7 Ga outcrop sample from the Fortescue Group,Pilbara Craton,Western Australia

The hydrocarbons preserved in an Archean rock were extracted, and their composition and distribution in consecutive slices from the outside to the inside of the rock were examined. The 2.7 Ga rock was collected from the Fortescue Group in the Pilbara region, Western Australia. The bitumen I (solvent‐extracted rock) and bitumen II (solvent‐extracted hydrochloric acid‐treated rock) fractions have different hydrocarbon compositions. Bitumen I contains only trace amounts of aliphatic hydrocarbons and virtually no aromatic hydrocarbons. In contrast, bitumen II contains abundant aliphatic and aromatic hydrocarbons. The difference seems to reflect the weathering history and preservational environment of the investigated rock. Aliphatic hydrocarbons in bitumen I are considered to be mainly from later hydrocarbon inputs, after initial deposition and burial, and are therefore not indigenous. The lack of aromatic hydrocarbons in bitumen I suggests a severe weathering environment since uplift and exposure of the rock at the Earth's surface in the Cenozoic. On the other hand, the high abundance of aromatic hydrocarbons in bitumen II suggests that bitumen II hydrocarbons have been physically isolated from removal by their encapsulation within carbonate minerals. The richness of aromatic hydrocarbons and the relative scarcity of aliphatic hydrocarbons may reflect the original compositions of organic materials biosynthesised in ancient organisms in the Archean era, or the high thermal maturity of the rock. Cyanobacterial biomarkers were observed in the surficial slices of the rock, which may indicate that endolithic cyanobacteria inhabited the surface outcrop. The distribution of aliphatic and aromatic hydrocarbons implies a high thermal maturity, which is consistent with the lack of any specific biomarkers, such as hopanes and steranes, and the prehnite–pumpellyite facies metamorphic grade.     

Variabilité de l’industrie lithique entre les structures de l’habitation no 1 de Mezhyrich,site du Paléolithique supérieur d’Ukraine

The investigation of the lithic assemblages from three archaeological structures of the Upper Palaeolithic Mezhyrich site, mammoth bone dwelling no. 1, nearby located pit no. 7 and workshop with a portion of cultural layer situated on the border of the pit, exhibits a sufficient diversity of the main indexes of flint assemblages. According to the latter, the main flint resources, cores and large pieces of flint, as well as blades and several tools (scrapers), were kept just in the dwelling. At the same time, the remains of “debitage” and the modification products of several tools (burin spalls) are more numerous in the pit and the workshop. The higher percentages of backed microliths, included the forms with diagnostic projectile impact fracture, and burins with several working edges are also observed in the assemblages of the last two archaeological structures.     

Tracing the genetic origin of Europe's first farmers reveals insights into their social organization

Farming was established in Central Europe by the Linearbandkeramik culture (LBK), a well-investigated archaeological horizon, which emerged in the Carpathian Basin, in today''s Hungary. However, the genetic background of the LBK genesis is yet unclear. Here we present 9 Y chromosomal and 84 mitochondrial DNA profiles from Mesolithic, Neolithic Starčevo and LBK sites (seventh/sixth millennia BC) from the Carpathian Basin and southeastern Europe. We detect genetic continuity of both maternal and paternal elements during the initial spread of agriculture, and confirm the substantial genetic impact of early southeastern European and Carpathian Basin farming cultures on Central European populations of the sixth–fourth millennia BC. Comprehensive Y chromosomal and mitochondrial DNA population genetic analyses demonstrate a clear affinity of the early farmers to the modern Near East and Caucasus, tracing the expansion from that region through southeastern Europe and the Carpathian Basin into Central Europe. However, our results also reveal contrasting patterns for male and female genetic diversity in the European Neolithic, suggesting a system of patrilineal descent and patrilocal residential rules among the early farmers.     

A Human Deciduous Tooth and New 40Ar/39Ar Dating Results from the Middle Pleistocene Archaeological Site of Isernia La Pineta,Southern Italy

Isernia La Pineta (south-central Italy, Molise) is one of the most important archaeological localities of the Middle Pleistocene in Western Europe. It is an extensive open-air site with abundant lithic industry and faunal remains distributed across four stratified archaeosurfaces that have been found in two sectors of the excavation (3c, 3a, 3s10 in sect. I; 3a in sect. II). The prehistoric attendance was close to a wet environment, with a series of small waterfalls and lakes associated to calcareous tufa deposits. An isolated human deciduous incisor (labelled IS42) was discovered in 2014 within the archaeological level 3 coll (overlying layer 3a) that, according to new ⁴⁰Ar/³⁹Ar measurements, is dated to about 583–561 ka, i.e. to the end of marine isotope stage (MIS) 15. Thus, the tooth is currently the oldest human fossil specimen in Italy; it is an important addition to the scanty European fossil record of the Middle Pleistocene, being associated with a lithic assemblage of local raw materials (flint and limestone) characterized by the absence of handaxes and reduction strategies primarily aimed at the production of small/medium-sized flakes. The faunal assemblage is dominated by ungulates often bearing cut marks. Combining chronology with the archaeological evidence, Isernia La Pineta exhibits a delay in the appearance of handaxes with respect to other European Palaeolithic sites of the Middle Pleistocene. Interestingly, this observation matches the persistence of archaic morphological features shown by the human calvarium from the Middle Pleistocene site of Ceprano, not far from Isernia (south-central Italy, Latium). In this perspective, our analysis is aimed to evaluate morphological features occurring in IS42.     

Multi-Mode Binding of Cellobiohydrolase Cel7A from Trichoderma reesei to Cellulose

Enzymatic hydrolysis of recalcitrant polysaccharides like cellulose takes place on the solid-liquid interface. Therefore the adsorption of enzymes to the solid surface is a pre-requisite for catalysis. Here we used enzymatic activity measurements with fluorescent model-substrate 4-methyl-umbelliferyl-β-D-lactoside for sensitive monitoring of the binding of cellobiohydrolase TrCel7A from Trichoderma reesei to bacterial cellulose (BC). The binding at low nanomolar free TrCel7A concentrations was exclusively active site mediated and was consistent with Langmuir''s one binding site model with K _d and A _max values of 2.9 nM and 126 nmol/g BC, respectively. This is the strongest binding observed with non-complexed cellulases and apparently represents the productive binding of TrCel7A to cellulose chain ends on the hydrophobic face of BC microfibril. With increasing free TrCel7A concentrations the isotherm gradually deviated from the Langmuir''s one binding site model. This was caused by the increasing contribution of lower affinity binding modes that included both active site mediated binding and non-productive binding with active site free from cellulose chain. The binding of TrCel7A to BC was found to be only partially reversible. Furthermore, the isotherm was dependent on the concentration of BC with more efficient binding observed at lower BC concentrations. The phenomenon can be ascribed to the BC concentration dependent aggregation of BC microfibrils with concomitant reduction of specific surface area.     

Hyperostosis frontalis interna: archaeological evidence of possible microevolution of human sex steroids?

Hyperostosis frontalis interna is a restricted bilateral thickening of the frontal endocranial surface, which is frequently found in postmenopausal females today. Surprisingly, this condition had a higher male prevalence in its rare archaeological records. This is again highlighted by the oldest known male European hyperostosis frontalis interna case in an adult Celtic from 100 BC presented here. This unique specimen supports earlier suggestions of the possible microevolution of human endocrine regulation, e.g. by sex steroids, and its pathoanatomical impact.     

In search of the last common ancestor: new findings on wild chimpanzees

Modelling the behaviour of extinct hominins is essential in order to devise useful hypotheses of our species'' evolutionary origins for testing in the palaeontological and archaeological records. One approach is to model the last common ancestor (LCA) of living apes and humans, based on current ethological and ecological knowledge of our closest living relations. Such referential modelling is based on rigorous, ongoing field studies of the chimpanzee (Pan troglodytes) and the bonobo (Pan paniscus). This paper reviews recent findings from nature, focusing on those with direct implications for hominin evolution, e.g. apes, using elementary technology to access basic resources such as food and water, or sheltering in caves or bathing as thermoregulatory adaptations. I give preference to studies that directly address key issues, such as whether stone artefacts are detectible before the Oldowan, based on the percussive technology of hammer and anvil use by living apes. Detailed comparative studies of chimpanzees living in varied habitats, from rainforest to savannah, reveal that some behavioural patterns are universal (e.g. shelter construction), while others show marked (e.g. extractive foraging) or nuanced (e.g. courtship) cross-populational variation. These findings allow us to distinguish between retained, primitive traits of the LCA versus derived ones in the human lineage.     

Downregulation of MTAP promotes Tumor Growth and Metastasis by regulating ODC Activity in Breast Cancer

5''-Methylthioadenosine phosphorylase (MTAP) is a key enzyme in the methionine salvage pathway and has been reported to suppress tumorigenesis. The MTAP gene is located at 9p21, a chromosome region often deleted in breast cancer (BC). However, the clinical and biological significance of MTAP in BC is still unclear. Here, we reported that MTAP was frequently downregulated in 41% (35/85) of primary BCs and 89% (8/9) of BC cell lines. Low expression of MTAP was significantly correlated with a poor survival of BC patients (P=0.0334). Functional studies showed that MTAP was able to suppress both in vitro and in vivo tumorigenic ability of BC cells, including migration, invasion, angiogenesis, tumor growth and metastasis in nude mice with orthotopic xenograft tumor of BC. Mechanistically, we found that downregulation of MTAP could increase the polyamine levels by activating ornithine decarboxylase (ODC). By treating the MTAP-repressing BC cells with specific ODC inhibitor Difluoromethylornithine (DFMO) or treating the MTAP-overexpressing BC cells with additional putrescine, metastasis-promoting or -suppressing phenotype of these MTAP-manipulated cells was significantly reversed, respectively. Taken together, our data suggested that MTAP has a critical metastasis-suppressive role by tightly regulating ODC activity in BC cells, which may serve as a prominent novel therapeutic target for advanced breast cancer treatment.     

Un exemple de gestion des géo-ressources au Paléolithique supérieur en moyenne montagne : le Badegoulien de la grotte du Rond-du-Barry (Sinzelles,Polignac, Haute-Loire)

Rond-du-Barry cave is situated in the centre of the Cenozoïc sedimentary basin of Puy-en-Velay in a mountainous environment. It contains Middle Palaeolithic, Badegoulian, Magdalenian and more recent occupation levels. Lying between two major river corridors (the Loire to the west and the Allier to the east), this site provides a special opportunity for defining exploitation and management modalities linked to the territory occupied by the prehistoric humans who inhabited the cave and the role played by the landscape's structural elements in human behavior at the end of the Upper Pleistocene. Lithic raw material analysis of the archaeological assemblages allowed us to define the dispersal of raw materials used in the site. Such dispersal has for some time been considered to provide a reliable reflection of actual movements of human groups. Our study, based on a modified methodology incorporating the concept of a chaine évolutive for flint, focused on the lithic artifacts from Rond-du-Barry unit F2, which are attributed to the Badegoulian. The results of our study differ from those of previous studies in terms of the diversity of the raw material being used and the frequency of occurrence for each type. Our conclusion is that Badegoulian humans were not physically constrained by a familiar territory, but traveled and/or traded widely in their quest for suitable raw materials. The diversity in the lithic raw materials, gathered locally and semi-locally from different primary and secondary outcrops demonstrates this territorial range. Importation of siliceous raw material originating from the meridional edge of the Paris basin (Berry, Touraine) suggests a planned resource-use strategy for obtaining large pieces of flint, which are rare in the regional outcrops. However, unraveling the resource use strategies to this degree of intention lies beyond what can be revealed by the lithic material alone.     

Topographic controls on black carbon accumulation in Alaskan black spruce forest soils: implications for organic matter dynamics

There is still much uncertainty as to how wildfire affects the accumulation of burn residues (such as black carbon (BC)) in the soil, and the corresponding changes in soil organic carbon (SOC) composition in boreal forests. We investigated SOC and BC composition in black spruce forests on different landscape positions in Alaska, USA. Mean BC stocks in surface mineral soils (0.34 ± 0.09 kg C m^?2) were higher than in organic soils (0.17 ± 0.07 kg C m^?2), as determined at four sites by three different ¹³C Nuclear Magnetic Resonance Spectroscopy-based techniques. Aromatic carbon, protein, BC, and the alkyl:O-alkyl carbon ratio were higher in mineral soil than in organic soil horizons. There was no trend between mineral soil BC stocks and fire frequencies estimated from lake sediment records at four sites, and soil BC was relatively modern (<54–400 years, based on mean Δ¹⁴C ranging from 95.1 to ?54.7‰). A more extensive analysis (90 soil profiles) of mineral soil BC revealed that interactions among landscape position, organic layer depth, and bulk density explained most of the variance in soil BC across sites, with less soil BC occurring in relatively cold forests with deeper organic layers. We suggest that shallower organic layer depths and higher bulk densities found in warmer boreal forests are more favorable for BC production in wildfire, and more BC is integrated with mineral soil than organic horizons. Soil BC content likely reflected more recent burning conditions influenced by topography, and implications of this for SOC composition (e.g., aromaticity and protein content) are discussed.     

Metabolic flux analysis of Gluconacetobacter xylinus for bacterial cellulose production

Metabolic flux analysis was used to reveal the metabolic distributions in Gluconacetobacter xylinus (CGMCC no. 2955) cultured on different carbon sources. Compared with other sources, glucose, fructose, and glycerol could achieve much higher bacterial cellulose (BC) yields from G. xylinus (CGMCC no. 2955). The glycerol led to the highest BC production with a metabolic yield of 14.7 g/mol C, which was approximately 1.69-fold and 2.38-fold greater than that produced using fructose and glucose medium, respectively. The highest BC productivity from G. xylinus CGMCC 2955 was 5.97 g BC/L (dry weight) when using glycerol as the sole carbon source. Metabolic flux analysis for the central carbon metabolism revealed that about 47.96 % of glycerol was transformed into BC, while only 19.05 % of glucose and 24.78 % of fructose were transformed into BC. Instead, when glucose was used as the sole carbon source, 40.03 % of glucose was turned into the by-product gluconic acid. Compared with BC from glucose and fructose, BC from the glycerol medium showed the highest tensile strength at 83.5 MPa, with thinner fibers and lower porosity. As a main byproduct of biodiesel production, glycerol holds great potential to produce BC with superior mechanical and microstructural characteristics.     

L'espace minéral au Paléolithique moyen dans le Sud du Massif central : premiers résultats pétroarchéologiques

The Middle Palaeolithic mineral environment in the South of the Massif Central: preliminary petroarchaeological results. Five Middle-Palaeolithic assemblages coming from archaeological sites in the Haute-Loire and Ardèche dated to isotopic stages 7 to 5 have been studied using a petroarchaeological method based on the optimization of observation techniques at different scales with respect to genetic and postgenetic characteristics of flint raw materials. The method reveals a relatively large collection area for the middle mountain sites (Sainte-Anne I, Baume-Vallée, Le Rond-de-Saint-Arcons, Rochelimagne), but apparently a smaller one for the site of Payre, located nearby the side of the Rhône Valley. For all sites, gathering is predominantly local, but some distant sources are utilised too. The rare exogenous materials, for example the Bedoulian flint from Ardèche identified in the Velay assemblages (Sainte-Anne I, Baume-Vallée) are in fact located in the heart of the massif as well as in secondary deposits and thus do not allow one to establish firm circulation routes for, or certain contact between the relevant human groups. To cite this article: P. Fernandes et al., C. R. Palevol 5 (2006).     

Roles of Thermophiles and Fungi in Bitumen Degradation in Mostly Cold Oil Sands Outcrops

Oil sands are surface exposed in river valley outcrops in northeastern Alberta, where flat slabs (tablets) of weathered, bitumen-saturated sandstone can be retrieved from outcrop cliffs or from riverbeds. Although the average yearly surface temperature of this region is low (0.7°C), we found that the temperatures of the exposed surfaces of outcrop cliffs reached 55 to 60°C on sunny summer days, with daily maxima being 27 to 31°C. Analysis of the cooccurrence of taxa derived from pyrosequencing of 16S/18S rRNA genes indicated that an aerobic microbial network of fungi and hydrocarbon-, methane-, or acetate-oxidizing heterotrophic bacteria was present in all cliff tablets. Metagenomic analyses indicated an elevated presence of fungal cytochrome P450 monooxygenases in these samples. This network was distinct from the heterotrophic community found in riverbeds, which included fewer fungi. A subset of cliff tablets had a network of anaerobic and/or thermophilic taxa, including methanogens, Firmicutes, and Thermotogae, in the center. Long-term aerobic incubation of outcrop samples at 55°C gave a thermophilic microbial community. Analysis of residual bitumen with a Fourier transform ion cyclotron resonance mass spectrometer indicated that aerobic degradation proceeded at 55°C but not at 4°C. Little anaerobic degradation was observed. These results indicate that bitumen degradation on outcrop surfaces is a largely aerobic process with a minor anaerobic contribution and is catalyzed by a consortium of bacteria and fungi. Bitumen degradation is stimulated by periodic high temperatures on outcrop cliffs, which cause significant decreases in bitumen viscosity.     

First Direct Evidence of Chalcolithic Footwear from the Near Eastern Highlands

In 2008, a well preserved and complete shoe was recovered at the base of a Chalcolithic pit in the cave of Areni-1, Armenia. Here, we discuss the chronology of this find, its archaeological context and its relevance to the study of the evolution of footwear. Two leather samples and one grass sample from the shoe were dated at the Oxford Radiocarbon Accelerator Unit (ORAU). A third leather sample was dated at the University of California-Irvine Accelerator Mass Spectrometry Facility (UCIAMS). The R_Combine function for the three leather samples provides a date range of 3627–3377 Cal BC (95.4% confidence interval) and the calibrated range for the straw is contemporaneous (3627–3377 Cal BC). The shoe was stuffed with loose, unfastened grass (Poaceae) without clear orientation which was more than likely used to maintain the shape of the shoe and/or prepare it for storage. The shoe is 24.5 cm long (European size 37), 7.6 to 10 cm wide, and was made from a single piece of leather that wrapped around the foot. It was worn and shaped to the wearer''s right foot, particularly around the heel and hallux where the highest pressure is exerted in normal gait. The Chalcolithic shoe provides solid evidence for the use of footwear among Old World populations at least since the Chalcolithic. Other 4^th millennium discoveries of shoes (Italian and Swiss Alps), and sandals (Southern Israel) indicate that more than one type of footwear existed during the 4^th millennium BC, and that we should expect to discover more regional variations in the manufacturing and style of shoes where preservation conditions permit.     

Microbial communities and their ability to oxidize n-alkanes in the area of release of gas- and oil-containing fluids in Mid-Baikal (Cape Gorevoi Utes)

The microbial community in the area of oil seep in Mid-Baikal (Cape Gorevoi Utes) was studied. The number of microorganisms that oxidize normal hydrocarbons, petroleum, and easily accessible organic matter in the water mass of the lake, bottom sediments, and bitumen structures was studied in 2005?C2009. The high heterogeneity of the distribution of microorganisms associated with the deparaffination of oil in the areas of oil seeps was noted. The maximum concentrations of hydrocarbon-oxidizing microorganisms in the samples of bottom water above bitumen structures (up to 2200 ± 175 CFU/mL) and in bitumen structures themselves (up to 170 000 ± 13 000 CFU/g) were determined. A model experiment showed that in the conditions of low temperatures (4°C) the degradation of the fraction of oil n-alkanes by the natural microbial community reaches 90% over a period of 60 days.     

Prognostic Significance of High VEGF-C Expression for Patients with Breast Cancer: An Update Meta Analysis

BackgroundThe prognostic significance of vascular endothelial growth factor C (VEGF-C) expression in breast cancer (BC) patients remains controversial. Therefore, this meta-analysis was performed to determine the prognostic significance of VEGF-C expression in BC patients.ResultsThe present meta analysis totally included 21 eligible studies and 2828 patients with BC. The combined HRs were 1.87(95% CI 1.25–2.79, P = 0.001) for DFS and 1.96(95% CI 1.15–3.31, P = 0.001) for OS. The pooled HRs of non-Asian subgroup were 2.04(95%CI 1.36–3.05, P = 0.001) for DFS and 2.61(95%CI 1.51–4.52, P = 0.001) for OS, which were significantly higher than that of Asian subgroup. The funnel plot for publication bias was symmetrical. The further Egger''s test and Begg''s test did not detect significant publication bias (all P>0.05).ConclusionsThe present meta analysis strongly supported the prognostic role of VEGF-C expression for DFS and OS in BC patients, especially for patients in non-Asian countries. Furthermore, stratification by VEGF-C expression may help to optimize the treatments and the integrated managements for BC patients.     

Effects of Bitumen Deposit on Soil Physico-Chemical Characteristics

Soils in the bitumen deposit area of Nigeria were analyzed for the physico-chemical characteristics and element contents to determine the level of contamination by the natural resource and to provide a framework for establishing relationships between the chemistry of mineral deposit and its host soils. The physico-chemical parameters were determined using standard analytical methods, while the elemental concentrations were determined by Energy Dispersive X-ray Fluorescence Spectrometry technique. The results revealed that soils had higher concentrations of associated hydrocarbon formation elements than other Nigerian soils but lower than the sand and bitumen fractions of Nigerian bituminous sands, indicating contamination of the bitumen host soils by the mineral deposit. Strong positive correlations existed between some elements in the soils, suggesting common sources or chemical similarities. Positive correlations are shown by the results of the cross plot analysis, which establish relationships between the soils and the bitumen deposit, indicating that contamination of the soils could easily affect other components of the ecosystem, viz water and vegetation.     

Modelling the long-term response to positive and negative priming of soil organic carbon by black carbon

Observed increases in the mineralization rate of labile organic carbon (LOC) in the presence of black carbon (BC) have led to speculation that corresponding decreases in non-pyrogenic (i.e. non-BC) soil organic carbon (npSOC) could significantly reduce or negate the C sequestration benefit of BC in soils. Here we show that the potential effect of an increased LOC decomposition rate on long-term npSOC stocks is negligible, even when using assumptions that would favour large losses, potentially causing no more than 3–4 % loss of npSOC over 100 years if 50 % of above-ground crop residues were converted to BC annually. Conversely, if the BC-stimulated enhanced stabilization of npSOC that has been observed in laboratory trials is extrapolated to the long-term, it would greatly increase soil carbon stocks by 30–60 %. Annual additions of BC derived from crop residues would increase total SOC (including both BC and npSOC) by an amount five times greater than the potential increase from enhanced stabilization and an order of magnitude greater than losses of npSOC caused by annual removals of biomass to provide BC feedstock.