Heavy metal pollution and element speciation in sediments of the rivers Mulde and Elbe with particular consideration of arsenic and lead

Anhand von Sedimenten wurde die Belastung der Mulde und Elbe mit Schwermetallen und Arsen untersucht. Für die Abschätzung des Einflusses der Mulde auf die Sedimentqualität der Elbe wurden Tiefenprofile in einem Abschnitt von oberhalb der Muldemündung bis unterhalb der Stadt Magdeburg abgeteuft. Außerdem wurden die Flüsse Freiberger, Zwickauer und Vereinte Mulde beprobt. Die Sedimente der Freiberger Mulde sind mit Arsen, Blei und Cadmium stark angereichert, während sich diejenigen der Zwickauer Mulde hauptsächlich durch hohe Cadmium- und Uran-Gehalte auszeichnen. In den Elbesedimenten liegen bereits oberhalb der Muldemündung erhöhte Konzentrationen von Blei und Cadmium vor. Nach dem Zufluss der Mulde findet jedoch ein rascher Rückgang der Schwermetallbelastung statt. Die Bindungsformen der Schwermetalle und von Arsen wurden anhand von sequentiellen Elutionsverfahren in Anlehnung an FÖRSTNER [1982] und KEON [2001] ermittelt. Arsen, Blei und Cadmium liegen in den Muldesedimenten in sehr instabilen Verbindungen vor und sind somit potenziell mobilisierbar. Außerdem sind Teile des Arsens in der toxischen dreiwertigen Form enthalten. Dagegen liegen in der Elbe Bindungen hoher Stabilität vor. Insgesamt geht daher von den Sedimenten der Freiberger und Zwickauer Mulde ein hohes Gefährdungspotenzial durch die Freisetzung der Schadstoffe aus, während dieses Risiko in der Elbe als gering zu bewerten ist. Die Sedimente sowohl der Freiberger als auch der Zwickauer Mulde sind durch den ehemaligen Bergbau im Erzgebirge geprägt. Dies wird durch die Änderung der Bleiisotopenverhältnisse im Tiefenprofil bestätigt. In der Elbe wird die Bleiisotopie durch die Zufuhr anthropogenen Bleis aus der Verbrennung von Benzin bestimmt. Die Mündung der Mulde führt zu einer unwesentlichen Veränderung der Bleiisotopenverhältnisse in der Elbe. Insbesondere die Bleiisotopenverhältnisse belegen eine nur geringe Auswirkung der stark belasteten Muldesedimente auf die Wasser- und Sedimentqualität der Elbe.On the basis of sediment analyses the pollution of the rivers Mulde and Elbe with heavy metals and arsenic was investigated. To assess the influence of the Mulde on the sediment quality in the Elbe depth profiles were taken in a section upstream the mouth of the Mulde to downstream the city of Magdeburg. In addition the rivers Freiberger, Zwickauer and Vereinte Mulde were sampled. The sediments of the Freiberger Mulde are highly enriched with arsenic, lead and cadmium whereas those of the Zwickauer Mulde are characterised by high amounts of cadmium and uranium. In the sediments of the Elbe increased concentrations of lead and cadmium already occur upstream of the mouth of the Mulde. After the Mulde confluence an initial increase followed by a rapid decrease of the heavy metal pollution occurs. The bonding forms of the heavy metals and arsenic were determined by sequential extraction methods. The applied methods followed those of FOERSTNER [1982] and KEON [2001]. In the Mulde sediments arsenic, cadmium and lead occur in very unstable bonding forms and are potentially mobile. A substantial amount of arsenic occurs in the toxic trivalent form. In contrast in the Elbe the bonding forms are of high stability. Due to a the possible release of pollutants from the sediments the Freiberger and Zwickauer Mulde must be considered as highly hazardous to the environment. In the Elbe this hazard can be ranked as rather low. The sediments of the Freiberger and Zwickauer Mulde are affected by the former mining in the Ore Mountains. This is corroborated by the change of the lead isotope ratios in the depth profiles. In the Elbe the lead isotopes are characterised by the supply of anthropogenic lead from the fuel combustion. The confluence of the Mulde causes only minor changes of the lead isotope ratios in the Elbe. Especially the isotope ratios document an only slight environmental influence of the highly polluted sediments of the Mulde on the water and sediment quality of the Elbe

Gestão de riscos na cadeia de suprimentos por meio da visão baseada em recursos

ResumoO objetivo deste artigo  é  salientar  que  os riscos da cadeia de suprimentos podem ser transformados em vantagem competitiva segundo a Visão Baseada em Recursos.  O aperfeiçoamento dos processos, a otimização dos recursos, a melhoria do desempenho da organização, adequada administração dos riscos da cadeia de suprimentos podem resultar em maiores lucros para as organizações. O artigo de caráter qualitativo propõe, a partir de uma revisão bibliográfica,  adaptar  a ferramenta visão baseada em recursos na cadeia de suprimentos e relatar os possíveis benefícios. O presente artigo apresenta que a estratégia que consiste  em  explorar seus  potenciais internos e capacidades próprias é possível e viável.  Palavras-chave: Riscos, Cadeia de Suprimentos, Visão Baseada em Recursos, Vantagem competitiva. Abstract:The aim of this paper is to highlight the risks of supply chain can be transformed into competitive advantage according to the Resource Based View. The process improvement, optimization of resources, improvement of organizational performance, proper management of risks in the supply chain can result in higher profits for organizations. The article proposes a qualitative nature, from a literature review, adapt the tool resource-based view in the supply chain and report the possible benefits. This paper presents the strategy  of exploiting its potential internal and capabilities is possible and feasible.Key-words: Risk, Supply Chain, Resource-Based View, Competitive Advantage

Succinate receptor 1 inhibits mitochondrial respiration in cancer cells addicted to glutamine

Cancer cells display metabolic alterations to meet the bioenergetic demands for their high proliferation rates. Succinate is a central metabolite of the tricarboxylic acid (TCA) cycle, but was also shown to act as an oncometabolite and to specifically activate the succinate receptor 1 (SUCNR1), which is expressed in several types of cancer. However, functional studies focusing on the connection between SUCNR1 and cancer cell metabolism are still lacking. In the present study, we analyzed the role of SUCNR1 for cancer cell metabolism and survival applying different signal transduction, metabolic and imaging analyses. We chose a gastric, a lung and a pancreatic cancer cell line for which our data revealed functional expression of SUCNR1. Further, presence of glutamine (Gln) caused high respiratory rates and elevated expression of SUCNR1. Knockdown of SUCNR1 resulted in a significant increase of mitochondrial respiration and superoxide production accompanied by an increase in TCA cycle throughput and a reduction of cancer cell survival in the analyzed cancer cell lines. Combination of SUCNR1 knockdown and treatment with the chemotherapeutics cisplatin and gemcitabine further increased cancer cell death. In summary, our data implicates that SUCNR1 is crucial for Gln-addicted cancer cells by limiting TCA cycle throughput, mitochondrial respiration and the production of reactive oxygen species, highlighting its potential as a pharmacological target for cancer treatment

Loss of Xenopus cadherin-11 leads to increased Wnt/β-catenin signaling and up-regulation of target genes c-myc and cyclin D1 in neural crest

AbstractXenopus cadherin-11 (Xcadherin-11) is an exceptional cadherin family member, which is predominantly expressed in cranial neural crest cells (NCCs). Apart from mediating cell–cell adhesion it promotes cranial NCC migration by initiating filopodia and lamellipodia formation. Here, we demonstrate an unexpected function of Xcadherin-11 in NCC specification by interfering with canonical Wnt/β-catenin signaling. Loss-of-function experiments, using a specific antisense morpholino oligonucleotide against Xcadherin-11, display a nuclear β-catenin localization in cranial NCCs and a broader expression domain of the proto-oncogene cyclin D1 which proceeds c-myc up-regulation. Additionally, we observe an enhanced NCC proliferation and an expansion of specific NCC genes like AP2 and Sox10. Thereby, we could allocate NCC proliferation and specification to different gene functions. To clarify which domain in Xcadherin-11 is required for early NCC development we tested different deletion mutants for their rescue ability in Xcadherin-11 morphants. We identified the cytoplasmic tail, specifically the β-catenin binding domain, to be necessary for proper NCC development. We propose that Xcadherin-11 is necessary for controlled NCC proliferation and early NCC specification in tuning the expression of the canonical Wnt/β-catenin target genes cyclin D1 and c-myc by regulating the concentration of the nuclear pool of β-catenin

Intravenous vitamin C in the treatment of allergies: an interim subgroup analysis of a long-term observational study

Objective Oxidative stress appears to be a key factor in the pathogenesis of allergic diseases and a potential therapeutic target in allergy treatment. Allergic diseases are reportedly associated with reduced plasma levels of ascorbate, which is a key physiological antioxidant. Ascorbate prevents excessive inflammation without reducing the defensive capacity of the immune system. Methods An interim analysis of a multicenter, prospective, observational study was conducted to investigate the change in disease-specific and nonspecific symptoms (fatigue, sleep disorders, depression, and lack of mental concentration) during adjuvant treatment with intravenous vitamin C (Pascorbin®; Pascoe, Giessen, Germany) in 71 patients with allergy-related respiratory or cutaneous indications. Results Between the start and end of treatment, the mean sum score of three disease-specific symptoms decreased significantly by 4.71 points and that of four nonspecific symptoms decreased significantly by 4.84 points. More than 50% of patients took no other allergy-related medication besides vitamin C. Conclusions Our observations suggest that treatment with intravenous high-dose vitamin C reduces allergy-related symptoms. Our observations form a basis for planning a randomized controlled clinical trial to obtain more definitive evidence of the clinical relevance of our findings. We also obtained evidence of ascorbate deficiency in allergy-related diseases

Radon Adsorption in Charcoal

Radon is pervasive in our environment and the second leading cause of lung cancer induction after smoking. Therefore, the measurement of radon activity concentrations in homes is important. The use of charcoal is an easy and cost-efficient method for this purpose, as radon can bind to charcoal via Van der Waals interaction. Admittedly, there are potential influencing factors during exposure that can distort the results and need to be investigated. Consequently, charcoal was exposed in a radon chamber at different parameters. Afterward, the activity of the radon decay products 214Pb and 214Bi was measured and extrapolated to the initial radon activity in the sample. After an exposure of 1 h, around 94% of the maximum value was attained and used as a limit for the subsequent exposure time. Charcoal was exposed at differing humidity ranging from 5 to 94%, but no influence on radon adsorption could be detected. If the samples were not sealed after exposure, radon desorbed with an effective half-life of around 31 h. There is also a strong dependence of radon uptake on the chemical structure of the recipient material, which is interesting for biological materials or diffusion barriers as this determines accumulation and transport