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The Serra Geral Group has high Cu concentrations in southern Brazil, including the Realeza (Paraná) region where Au and Ag also occur. The basalts (46.7-50.8 wt.% SiO2) have breccias at the top of 10 out of 31 studied flows in the Realeza section and at the top of 5 out of 7 analyzed flows in the Capanema section. Sand injectites occur at the top of basalts in 18 out of 23 flows from the Realeza section. The average content of Cu in three samples of mineralized breccias is 3788 ppm. One sample from a silicified sandstone sill intruded at the top of a basalt flow has up to 0.66 ppm Au. K2O was not leached during basalt alteration. The hydrothermal breccias, particularly when sand is present, show enrichment in U which leads to higher values of scintillometry (rate of emission of K, U and Th). In the basalts, breccias and sandstones, Pd (17.5 ± 8.4 ppb) is higher than Pt (12.5 ± 5 ppb), suggesting a hydrothermal remobilization of the metals. The Serra Geral Group is thus shown to have high potential for precious and base metal deposits. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to investigate biological effects and potential health risks due to two different metal-inert-gas (MIG) welding fumes (MIG welding of aluminium and MIG soldering of zinc coated steel) in healthy humans. In a threefold cross-over design study 12 male subjects were exposed to three different exposure scenarios. Exposures were performed under controlled conditions in the Aachener Workplace Simulation Laboratory (AWSL). On three different days the subjects were either exposed to filtered ambient air, to welding fumes from MIG welding of aluminium, or to fumes from MIG soldering of zinc coated materials. Exposure was performed for 6h and the average fume concentration was 2.5mgm−3. Before, directly after, 1 day after, and 7 days after exposure spirometric and impulse oscillometric measurements were performed, exhaled breath condensate (EBC) was collected and blood samples were taken and analyzed for inflammatory markers. During MIG welding of aluminium high ozone concentrations (up to 250μgm−3) were observed, whereas ozone was negligible for MIG soldering. For MIG soldering, concentrations of high-sensitivity CRP (hsCRP) and factor VIII were significantly increased but remained mostly within the normal range. The concentration of neutrophils increased in tendency. For MIG welding of aluminium, the lung function showed significant decreases in Peak Expiratory Flow (PEF) and Mean Expiratory Flow at 75% vital capacity (MEF 75) 7 days after exposure. The concentration of ristocetin cofactor was increased. The observed increase of hsCRP during MIG-soldering can be understood as an indicator for asymptomatic systemic inflammation probably due to zinc (zinc concentration 1.5mgm−3). The change in lung function observed after MIG welding of aluminium may be attributed to ozone inhalation, although the late response (7 days after exposure) is surprising. [Copyright &y& Elsevier]

Abstract: We compute the analytic torsion of a cone over a sphere of dimensions 1, 2, and 3, and we conjecture a general formula for the cone over an odd dimensional sphere. [Copyright &y& Elsevier]

Abstract: The molecular dynamics in thin films of isotactic poly(methylmethacrylate) is investigated by broadband dielectric spectroscopy. No shifts in the mean relaxation time of the dynamic glass transition are detected down to a film thickness of 6.6nm. These results are compared to previous measurements on thin films of isotactic poly(methylmethacrylate) [L. Hartmann et al., Eur. Phys. J. E 8 (2002) 145]. We show that in the latter case, the shifts in the dynamic glass transition are caused by an erroneous analysis of the experimental results. [Copyright &y& Elsevier]

The anticarcinogen conjugated linoleic acid (CLA) is a product of bacterial activity that isomerizes linoleic acid (LA) in the rumen of herbivores. Therefore, fatty dairy products in the human diet are enriched with CLA. Although bacteria capable of in vitro LA conjugation were detected in the human intestinal tract, CLA synthesis from dietary sunflower seed oil was not observed in gnotobiotic rats associated with these intestinal bacteria. The objective of the study was to investigate variables that affect LA conjugation. In vitro, LA conjugation was strongly inhibited by glucose and other substrates. Concentrations of 1.5 mmol glucose/L inhibited LA conjugation by 50%. Methyl-alpha-D-glucoside was a less effective inhibitor than glucose, and 2-deoxy-D-glucose did not inhibit LA conjugation at all. To analyze the concentration of carbohydrates in intestinal contents, the LA-conjugating bacterial mixed culture and human fecal microorganisms were introduced into germ-free rats. Samples of feces and cecum and colon contents of both groups exhibited in vitro LA-conjugating activity. Rats associated with human intestinal microorganisms contained 5.7 +/- 1. 3 mmol glucose/L in the cecal contents and 6.6 +/- 1.0 mmol glucose/L in the colonic contents. Rats associated with CLA-producing bacterial culture contained 3.4 +/- 1.3 mmol glucose/L in the cecal contents and 4.2 +/- 1.0 mmol glucose/L in the colonic contents. These values are within a range that may explain the observed inhibition of LA conjugation in vivo. [ABSTRACT FROM AUTHOR]

Pectin is a soluble indigestible polysaccharide that stimulates cecal polyamine formation in rats. Bacteroides and fusobacteria, two numerically dominant bacterial population groups in the large intestine, were found to synthesize in vitro high amounts of spermidine and putrescine. The purpose of this study was to elucidate the effect of pectin on the polyamine production by defined bacterial species in vivo. Germfree male Wistar rats (n = 18) were randomly assigned to one of three treatments: (i) monoassociation with Bacteroides thetaiotaomicron + fiber-free diet; (ii) diassociation with B. thetaiotaomicron + Fusobacterium varium + fiber-free diet or (iii) diassociation with B. thetaiotaomicron + F. varium + fiber-free diet + 10% pectin. The cecal contents of monoassociated rats fed fiber-free diet contained large amounts (1.51+/-0.21 micromol/dry total cecum content) of spermidine which was the major polyamine. The cecum of diassociated rats fed the fiber-free diet contained even higher concentrations of spermidine (2.53+/-0.21 micromol/dry total cecum content) and also putrescine, which was now the dominant polyamine (putrescine 0.32+/-0.28 vs. 3.01+/-0.28 micromol/dry total cecum content; monoassociation vs. diassociation). Pectin consumption by diassociated rats led to an additional increase in the cecal concentrations of all polyamines: putrescine, spermidine and spermine were 40, 37 and 100%, respectively, higher in the diassociated rats consuming the pectin diet than in those consuming the pectin-free diet. Since the microbial counts in the cecum did not differ in the diassociated treatment groups, the elevated concentrations of polyamines observed in the pectin group must have been due to stimulated bacterial polyamine synthesis. The decline of individual polyamines from cecum to feces detected at the end of the study in all treatment groups and the high microbial counts in the cecum and in feces suggest that bacterial polyamines are absorbed in cecum and colon. Pectin stimulates intestinal microbes to synthesize large amounts of polyamines which may be utilized by the host. [ABSTRACT FROM AUTHOR]

Conjugated linoleic acid (CLA) is produced from linoleic acid (LA) by bacteria in the rumen of herbivores. CLA enters the human diet mainly via milk fat and fatty beef; it acts as an effective anticarcinogen and exhibits other important physiological effects. The objective of the current study was to investigate the capability of a LA-conjugating bacterial community isolated from a human volunteer and associated with germ-free rats to supply the host with CLA. Gnotobiotic rats were fed a diet enriched with esterified LA in the form of sunflower-seed oil. The control group was fed the same diet and remained germ-free. Bacterial cell counts, in vitro LA-conjugation activities, and CLA concentration in feces and in the contents of various intestinal segments were determined. After 10 wk, various tissues were analyzed for CLA concentrations. LA-conjugation activity was found only in feces, cecum and colon content samples from associated rats, but CLA accumulation in various body tissues did not differ significantly between the two groups. The ratio of CLA to LA in feces and in cecal and colonic contents did not differ between groups, indicating that the microorganisms in the cecum and the colon do not synthesize substantial amounts of CLA in vivo and therefore, do not contribute to the CLA supplementation of the host. [ABSTRACT FROM AUTHOR]

Background: The objective of the study was to evaluate completion rates and toxic effects of an i.p. chemotherapy regimen in a cross-section of nonselected patients with ovarian cancer (OC). Patients and methods: All patients with stage IIIC OC consecutively operated at our institution from January 2006 to December 2007 were prospectively collected and analyzed. Results: Eighty-nine patients with stage IIIC OC optimally debulked were evaluated for this study. An i.p. port was primarily placed in 53 of 89 (60%), and i.p. chemotherapy was recommended in 55 patients. Reasons for not recommending i.p. chemotherapy in patients optimally debulked included postoperative complications (n = 7: 8%), poor nutritional/functional status (n = 5: 6%), and extensive surgery including bowel resection (n = 9: 10%). Thirty-three patients (33/55: 60%) recommended to receive i.p. chemotherapy-initiated i.p. treatment. Fifty-two percent of those beginning i.p. therapy (17/33) received three or more cycles with 36% (12/33) successfully completing six cycles. Reasons for discontinuation included grade 3-4 nephrotoxicity in 3 of 21 (14%), febrile neutropenia/sepsis in 3 of 21 (14%), port infection or malfunction in 8 of 21 (38%). Conclusions: The i.p. chemotherapy regimen used in a consecutive cohort of patients carries could be completed in only a small percentage of patients. Less toxic regimens with higher acceptability should be considered. [ABSTRACT FROM AUTHOR]

Abstract: Bitelechelic polydimethylsiloxanes (PDMS) and 2-hydroxyethylacrylate (HEA)/acrylic acid(AA) were photopolymerized to give nanophase separated amphiphilic 20-μm-thin coatings covalently attached to glass. The coatings quickly take up the antimicrobial surfactant cetyltrimethylammonium chloride (CTAC). After a 30 min loading period the release of CTAC in water was followed by simultaneously measuring both the antimicrobial activity of the coating''s surface against Staphylococcus aureus and the release of the structurally related dye Rhodamine B. Depending on the composition the antimicrobial activity remained up to 3 weeks. The influence of different pH, varying sodium chloride concentrations, and the surfactant Pluronic was investigated. However, even in the cases of 160 mM NaCl and 1 wt.% Pluronic as release medium, the antimicrobial activity remained more than 6 days in case of a coating consisting of 45 wt.% PDMS, 31 wt.% PHEA, and 25 wt.% PAA. Mechanistic investigations revealed that the CTAC-loaded coatings act like contact-active surfaces, i.e., they do not kill microbes in the surrounding solution but only on their surface. This supports our hypothesis that the antimicrobial action is due to a concentration gradient of CTAC on the surface, allowing it to be antimicrobial on contact and to release only very low concentration of the biocide into the surrounding. [Copyright &y& Elsevier]

Abstract: Water and polymer dynamics in hydrogels based on random copolymers of hydrophilic poly(hydroxyl ethyl acrylate) (PHEA) and hydrophobic poly(ethyl acrylate) (PEA), in wide ranges of composition, were investigated by means of two dielectric techniques, thermally stimulated depolarization currents (TSDC) and, mainly, broadband dielectric relaxation spectroscopy (DRS) at several levels of relative humidity/water content. Water sorption of the hydrogels was studied by equilibrium sorption isotherms (ESI). Two secondary relaxations (γ and βsw ) and the primary (segmental) α relaxation associated with the glass transition of the copolymer matrix were followed and analyzed against copolymer composition and water content. The results show that the copolymers are homogeneous at nm scale, except at very high PEA content. Correlations were observed between results on the organization of water in the hydrogels and on water effects on polymer dynamics. Distinct changes in the dielectric response, in particular in the time scale and the dielectric strength of the βsw relaxation, at the water content of the completion of the first hydration layer indicate that water molecules themselves contribute to the dielectric response at higher water contents. Proton conductivity of the hydrogels at various levels of water content was also studied and correlation to segmental dynamics (decoupling) was analyzed. [Copyright &y& Elsevier]

Abstract: The reggies/flotillins were discovered as proteins upregulated during axon regeneration. Here, we show that expression of a trans-negative reggie-1/flotillin-2 deletion mutant, R1EA, which interferes with oligomerization of the reggies/flotillins, inhibited insulin-like growth factor (IGF)-induced neurite outgrowth in N2a neuroblastoma cells and impaired in vitro differentiation of primary rat hippocampal neurons. Cells expressing R1EA formed only short and broad membrane protrusions often with abnormally large growth cones. R1EA expression strongly perturbed the balanced activation of the Rho-family GTPases Rac1 and cdc42. Furthermore, focal adhesion kinase (FAK) activity was also enhanced by R1EA expression, while other signaling pathways like ERK1/2, PKC or PKB signaling were unaffected. These severe signaling defects were caused by an impaired recruitment of the reggie/flotillin-associated adaptor molecule CAP/ponsin to focal contacts at the plasma membrane. Thus, the reggies/flotillins are crucial for coordinated assembly of signaling complexes regulating cytoskeletal remodeling. [Copyright &y& Elsevier]

Ex vivo expansion of human CD34+ hematopoietic stem and progenitor cells (HSPCs) remains challenging due to induction of rapid cellular differentiation after detachment from the supporting bone marrow stem cell niche. However, a few leukemia-related chimeric transcription factors, including MLL fusion proteins, confer remarkable CD34+ ex vivo expansion capacity. In this study, we fused the coding sequence of a FKBP12-derived destabilization domain (DD) to an MLL-fusion gene (MLL-X) and then retrovirally expressed the protein switch in human CD34+ progenitors derived from healthy donors. In the presence of Shield1, a chemical inhibitor of DD fusion protein turnover, the cytokines FLT3-L and IL-3 were necessary and sufficient to yield massive and long-term expansion of DD-MLL-X engineered HSPC-derived late monocytic precursors, with normal karyotype preserved. Upon removal of Shield1, the cells completely lost self-renewal capacity, lost colony-forming properties and spontaneously differentiated, even after 150 days of ex vivo expansion. In the absence of Shield1, a five-day stimulation with IFNγ, LPS, and GM-CSF triggered robust monocytic differentiation. Immunophenotypic characterization revealed upregulation of the monocytic cell surface markers CD14, CD68, CD80, CCR2, and MHC class I and II, in well-accordance with cellular morphology as judged by cytospin preparations. Upregulation of inflammatory markers such as IL-6, IL-10, and CCL2 on mRNA level was detected by qRT-PCR. In functional assays, we finally demonstrated the propensity of the obtained cells to migrate towards the chemokine CCL2, attach to tissue-culture treated plastic surfaces and VCAM-1 under flow and shear stress, to produce reactive oxygen species and engulf both bacterial and cellular particles. Moreover, we demonstrated Fc receptor recognition and phagocytosis of Raji lymphoblastic tumor cells in a daratumumab antibody-dependent manner, proving their identity as monocytes. Taken together, we demonstrate the conversion of a harmful transcription factor to a useful tool for ex vivo blood cell production. Using this engineered protein switch, we were able to produce HSPC-derived late monocytic progenitors in large-scale and differentiate those towards functional monocytes under well-defined ex vivo conditions, both efficiently and quantitatively. This controllable system could set the stage for directed generation of patient-derived monocytes for cell-based immunotherapeutic approaches. [ABSTRACT FROM AUTHOR]