Screening and characterization of Lactobacillus strains producing large amounts of exopolysaccharides

A total of 182 Lactobacillus strains were screened for production of extracellular polysaccharides (EPS) by a new method: growth in liquid media with high sugar concentrations. Sixty EPS-positive strains were identified; 17 strains produced more than 100 mg/l soluble EPS. Sucrose was an excellent substrate for abundant EPS synthesis. The ability to produce glucans appears to be widespread in the genus Lactobacillus. The monosaccharide composition of EPS produced by Lactobacillus reuteri strain LB 121 varied with the growth conditions (solid compared to liquid medium) and the sugar substrates (sucrose or raffinose) supplied in the medium. Strain LB 121 produced both a glucan and a fructan on sucrose, but only a fructan on raffinose. This is the first report of fructan production by a Lactobacillus species. EPS production increased with increasing sucrose concentrations and involved extracellular sucrase-type enzymes.

The pedicled omentoplasty and split skin graft (POSSG) for reconstruction of large chest wall defects. A validity study of 34 patients

The aim of this study was to evaluate retrospectively the results of pedicled omentoplasty and split skin graft (POSSG) in reconstructing (full thickness) chest wall defects, and to define its role as a palliative procedure for local symptom control. Thirty-four patients with recurrent breast cancer (n = 25), radiation-induced necrosis (n = 5) or sarcoma (n = 4) of the chest wall were selected for the study. All patients underwent curative or palliative chest wall resection with reconstruction by pedicled omentoplasty and split skin graft (POSSG), between 1986 and 1994. Reconstructive outcome, complications, local tumour and symptom control following surgery was measured. The most common complication was shown to be partial necrosis of the omental flap (35%), followed by respiratory problems (26%), facial hernia (26%) and thoracic wound problems (15%), which were mostly treated in a conservative way (68%). The 3-year local tumour-free interval after POSSG in patients curatively treated for breast cancer is 16%. Seventy per cent of the patients who underwent palliative resection had longstanding relief of local pain, bleeding or foetor due to local tumour growth. It can be concluded that large (full thickness) chest wall defects after resection of local recurrence, primary malignancy or osteoradionecrosis of the chest wall can successfully be reconstructed by POSSG. Chest wall resection in patients treated with palliative intention is effective in local symptom control

Fifty tumor necrosis factor-based isolated limb perfusions for limb salvage in patients older than 75 years with limb-threatening soft tissue sarcomas and other extremity tumors

BACKGROUND: Isolated limb perfusion (ILP) with tumor necrosis factor (TNF) and melphalan is highly effective in treating limb-threatening soft tissue sarcoma (STS) and other bulky tumors. Because of fear of TNF-associated toxicity, ILP with TNF is not offered to older patients in some cancer centers, although especially in older patients, every attempt to avoid an amputation that may end their independence must be considered. METHODS: Out of 306 TNF-based ILPs, 50 ILPs were performed for limb salvage in 43 patients >75 years old (range, 75-91 years): 29 STS and 14 melanoma patients. RESULTS: In the STS patients, a response rate of 76% and a limb-salvage rate of 76% were achieved; in the melanoma patients, a 100% response rate and a 93% limb-salvage rate were achieved. Local toxicity was mild. The three postoperative deaths that occurred in the total series of 306 TNF-based ILPs in Rotterdam (75 years old after leakage-free perfusions and were not related to TNF but to extremely high-risk profiles in these three patients. CONCLUSIONS: Older patients should not be withheld a TNF-based ILP for limb salvage, because the procedure is safe and highly effective in these patients

Linking forest cover, soil erosion and mire hydrology to late-Holocene human activity and climate in NW Spain

This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 3.0 License (http://www.creativecommons.org/licenses/by-nc/3.0/) which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access page (http://www.uk.sagepub.com/aboutus/openaccess.htm).This article has been made available through the Brunel Open Access Publishing Fund.Forest clearance is one of the main drivers of soil erosion and hydrological changes in mires, although climate may also play a significant role. Because of the wide range of factors involved, understanding these complex links requires long-term multi-proxy approaches and research on the best proxies to focus. A peat core from NW Spain (Cruz do Bocelo mire), spanning the last ~3000 years, has been studied at high resolution by physical (density and loss on ignition (LOI)), geochemical (elemental composition) and palynological (pollen and non-pollen palynomorphs) analyses. Proxies related to mineral matter fluxes from the catchment (lithogenic tracers, Glomus and Entorrhiza), rainfall (Bromine), mire hydrology (HdV-18), human pressure (Cerealia-type, nitrophilous taxa and coprophilous fungi) and forest cover (mesophilous tree taxa) were the most useful to reconstruct the evolution of the mire and its catchment. Forest clearance for farming was one of the main drivers of environmental change from at least the local Iron Age (~2685 cal. yr BP) onwards. The most intense phase of deforestation occurred during Roman and Germanic times and the late Middle Ages. During these phases, the entire catchment was affected, resulting in enhanced soil erosion and severe hydrological modifications of the mire. Climate, especially rainfall, may have also accelerated these processes during wetter periods. However, it is noteworthy that the hydrology of the mire seems to have been insensitive to rainfall variations when mesophilous forest dominated. Abrupt changes were only detected once intense forest clearance commenced during the Iron Age/Roman transition (~2190 cal. yr BP) phase, which represented a tipping point in catchment's ability to buffer impacts. Overall, our findings highlight the importance of studying ecosystems' long-term trajectories and catchment-wide processes when implementing mire habitat protection measures.This work was funded by the projects CGL2010-20672 (Plan Nacional I+D+i, Spanish Ministry of Science and Innovation) and 10PXIB200182PR (General Directorate of I+D, Xunta de Galicia). N Silva-Sánchez and L López-Merino are currently supported by a FPU predoctoral scholarship (AP2010-3264) funded by the Spanish Government and a MINT postdoctoral fellowship funded by the Brunel Institute for the Environment, respectively

Imaging dielectric relaxation in nanostructured polymers by frequency modulation electrostatic force microscopy

We have developed a method for imaging the temperature-frequency dependence of the dynamics of nanostructured polymer films with spatial resolution. This method provides images with dielectric compositional contrast well decoupled from topography. Using frequency-modulation electrostatic-force-microscopy, we probe the local frequency-dependent (0.1–100 Hz) dielectric response through measurement of the amplitude and phase of the force gradient in response to an oscillating applied electric field. When the phase is imaged at fixed frequency, it reveals the spatial variation in dielectric losses, i.e., the spatial variation in molecular/dipolar dynamics, with 40 nm lateral resolution. This is demonstrated by using as a model system; a phase separated polystyrene/polyvinyl-acetate (PVAc) blend. We show that nanoscale dynamic domains of PVAc are clearly identifiable in phase images as those which light-up in a band of temperature, reflecting the variations in the molecular/dipolar dynamics approaching the glass transition temperature of PVAc

Modern and fossil non-pollen palynomorphs from the Basque mountains (western Pyrenees, France): the use of coprophilous fungi to reconstruct pastoral activity

International audienceThis paper presents results from a modern dataset of non-pollen palynomorphs and its application to aca. 2,000 year peat record from the same area in the western Pyrenees (Basque Country, France). The modern dataset is composed of 35 surface samples (moss polsters) from a mountainous pasture-woodland landscape. Airborne fungal spores (ascospores and conidia), found dominant in the dataset, are linked to the degree of landscape openness and grazing pressure. The complete spectrum of 13 selected spore-types of dung-related Ascomycetes is positively linked with grazing pressure. However, different dung affinities between the spore-types have been identified. These are types clearly related to high grazing pressure and types with no or unclear dung indicative value. The modern dataset is used to aid interpretation of the local fossil pollen record as an independent 'proxy' to assess past pastoral dynamics. This study confirms the utility of modern nonpollen palynomorphs from terrestrial ecosystems in the reconstruction of historical local pastoral activities but also shows their limitation. It may be necessary to extend such study to wetland ecosystems and to investigate the spatial dimension of some fungal spores

Palaeoecological study of a Weichselian wetland site in the Netherlands suggests a link with Dansgaard-Oeschger climate oscillation

Botanical microfossils, macroremains and oribatid mites of a Weichselian interstadial deposit in the central Netherlands point to a temporary, sub-arctic wetland in a treeless landscape. Radiocarbon dates and OSL dates show an age between ca. 54.6 and 46.6 ka cal BP. The vegetation succession, starting as a peat-forming wetland that developed into a lake, might well be linked with a Dansgaard-Oeschger climatic cycle. We suggest that during the rapid warming at the start of a D-O cycle, relatively low areas in the landscape became wetlands where peat was formed. During the more gradual temperature decline that followed, evaporation diminished; the wetlands became inundated and lake sediments were formed. During subsequent sub-arctic conditions the interstadial deposits were covered with wind-blown sand. Apart from changes in effective precipitation also the climate-related presence and absence of permafrost conditions may have played a role in the formation of the observed sedimentological sequence from sand to peat, through lacustrine sediment, with coversand on top. The Wageningen sequence may correspond with D-O event 12, 13 or 14. Some hitherto not recorded microfossils were described and illustrated

Middeleeuws Urk onder Wijk 6-6

Het gedurende twee jaar nauwkeurig volgen van graafwerkzaamheden onder de woning Wijk 6-6 in de oude dorpskern van Urk leverde een schat aan archeologische vondsten en waarnemingen op. Duidelijk werd dat op of nabij deze locatie van 1381 tot midden 15de eeuw het befaamde ‘Huze tot Orck’ stond. Een Sterkte die met soldaten, kruisbogen en kerkers de zeeroverij op de vaargeulen langs Urk moest bestrijden. Ook bleek dat er vanaf de 12de eeuw, misschien zelfs al eerder, op deze plek een grote boerderij stond. Die boerderij stond in een vrijwel boomloos landschap en maakte deel uit van een uitgestrekt lint van boerderijen dat langs de noordflank van de bult van Urk liep. De weg die de boerderijen verbond, is te herkennen in de nu nog bestaande Oude Straat van Urk en is de enige nog bestaande en functionerende middeleeuwse straat van Flevoland