Duplicate Experiments Research Articles

Evaluation of Arsenic Leaching Potential in Gold Mine Tailings Amended with Peat and Mine Drainage Treatment Sludge.

Peat and mine drainage treatment sludge can be valorized as amendments on mine sites to stabilize gold mine tailings and reduce the potential leaching of contaminants in pore water. However, the influence of organic amendments on the mobility of metalloids and/or metals in the tailings must be validated, as the leached contaminants may vary according to their type, nature, and origin. The objective of the present study was to evaluate over time the effect of peat- and/or Fe-rich sludge amendments on the mobility of As and metallic cations in the drainage water of tailings potentially producing contaminated neutral drainage. Ten duplicated weathering cell experiments containing tailings alone or amended with peat and/or Fe-rich sludge (5-10% dry weight) were performed and monitored for 112 d. The results showed that as low as 5% peat amendment would promote As mobility in tailings' pore water, with As concentrations exceeding Quebec discharge criteria (>0.2 mg L). In addition, As(III), the most mobile and toxic form, was predominant with 10% peat, whereas organic species were negligible in all cells. The use of peat alone as organic amendment for the stabilization of tailing contaminants could increase the risk of generating As-rich contaminated neutral drainage. Conversely, the mix of only 5% Fe-rich sludge with or without peat decreased As concentrations in leachates by 65 to 80%. Further studies on the use of "peat" or "peat + Fe-rich sludge" as cover or amendment should be conducted with a focus on Fe/As and Ca/As ratios.

Experimental Evaluation of Surface Water Sampling Variability for Environmental Monitoring in Iron Ore Operations

Environmental self-monitoring is a government requirement for Swedish process industries. This includes sampling and analysis of recipient water that might be adversely affected by emissions. The requirements for accredited analytical methods are strict, with well-defined measurement uncertainties, but estimations of the attendant sampling variability are seldom required, presented, or evaluated in environmental surface water sampling. The goal of this study was to perform an initial evaluation of the measurement variability for surface water sampling within the self-monitoring program for a large mining company in northern Sweden. The results indicate that the method for evaluation of sampling and measurement variability itself affects the results obtained. Therefore, the evaluation scope must be clearly defined in advance, so that the most appropriate approach, resulting in a realistic quantification of total variability, can be selected. This study shows that duplicate sampling experiments result in significantly larger sampling variability estimates when accounting for ambiguities in the sampling protocol than similar experiments under repeatability conditions. This is due to large temporal variations in stream flux and analyte concentrations in the evaluated sampling targets. The ambiguities in different sampling protocols must be fully described and considered when designing empirical evaluation experiments to allow valid evaluation of the total sampling and measurement system variability. An automated sampler using volume-proportional sampling to collect increments for composite samples is recommended to reduce unnecessary sampling variability and address significant temporal changes in stream flux and analyte concentrations appropriately.

Carcinogenicity of intermediate frequency magnetic field in Tg.rasH2 mice.

Although the likelihood of exposure to leaking intermediate frequency magnetic fields (MFs) from electronic devices, such as induction‐heating and wireless power transfer systems, has increased, biological data assessing the health risks associated with human exposure remain insufficient. We examined the carcinogenicity of a 20 kHz MF, a typical frequency produced by induction‐heating cookers, using a transgenic rasH2 mouse model. Twenty‐five male and female CByB6F1‐Tg(HRAS)2Jic mice were exposed to a 0.20 mT, 20 kHz MF (22 h/day) or sham‐exposed for 26 weeks. As a positive control, 10 male and female rasH2 mice from the same batch were administered a single intraperitoneal injection of 75 mg/kg N‐methyl‐N‐nitrosourea. A blinded histopathological evaluation was performed, and the same experiments were conducted twice, independently, to confirm the reproducibility of the results. Histopathological examination revealed that spontaneous neoplastic lesions, such as splenic hemangiosarcomas and gastric squamous cell papillomas, were less (1–3 per group) in the MF‐ and sham‐exposed groups. The frequency of the neoplastic lesions was not significantly different between the groups. Eight to ten mice in each positive‐control group exhibited malignant lymphoma. The outcomes were consistent between duplicated experiments, which indicates lack of carcinogenicity of 20 kHz MF in the rasH2 mouse model. Bioelectromagnetics. © 2019 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc.

14C release from irradiated stainless steel

ABSTRACTRadiocarbon (14C or carbon-14, half-life 5730 yr) is a key radionuclide in the assessment of the safety of a geological disposal facility (GDF) for radioactive waste. In particular, the radiological impact of gaseous carbon-14 bearing species has been recognized as a potential issue. Irradiated steels are one of the main sources of carbon-14 in the United Kingdom’s radioactive waste inventory. However, there is considerable uncertainty about the chemical form(s) in which the carbon-14 will be released. The objective of the work was to measure the rate and speciation of carbon-14 release from irradiated 316L(N) stainless steel on leaching under high-pH anoxic conditions, representative of a cement-based near field for low-heat generating wastes. Periodic measurements of carbon-14 releases to both the gas phase and to solution were made in duplicate experiments over a period of up to 417 days. An initial fast release of carbon-14 from the surface of the steel is observed during the first week of leaching, followed by a drop in the rate of release at longer times. Carbon-14 is released primarily to the solution phase with differing fractions released to the gas phase in the two experiments: about 1% of the total release in one and 6% in the other. The predominant dissolved carbon-14 releases are in inorganic form (as 14C-carbonate) but also include organic species. The predominant gas-phase species are hydrocarbons with a smaller fraction of 14CO (which may include some volatile oxygen-containing carbon-species). The experiments are continuing, with final sampling and termination planned after leaching for a total of two years.

The discovery of chemically produced mass independent isotope effects: The physical chemistry basis and applications to the early solar system, planetary atmospheres, and the origin of life

The discovery of chemically produced mass independent isotope effects: The physical chemistry basis and applications to the early solar system, planetary atmospheres, and the origin of life

In vitro screening of cell bioenergetics to assess mitochondrial dysfunction in drug development

Drug-induced mitochondrial toxicity is considered as a common cellular mechanism that can induce a variety of organ toxicities. In the present manuscript, 17 in vitro mitochondrial toxic drugs, reported to induce Drug-Induced Liver Injury (DILI) and 6 non-mitochondrial toxic drugs (3 with DILI and 3 without DILI concern), were tested in HepG2 cells using a bioenergetics system. The 17 mitochondrial toxic drugs represent a wide variety of mitochondrial dysfunctions as well as DILI and include 4 pairs of drugs which are structurally related but associated with different DILI concerns in human. Cell bioenergetics were measured using the XF96e analyzer which simultaneous monitor oxygen consumption rate (OCR) and extracellular acidification rate (ECAR), indirect measurements of oxidative phosphorylation and glycolysis, respectively. OCR associated with ATP production, maximal respiration, proton leak and spare respiratory capacity, were also assessed. Duplicate experiments resulted in a sensitivity of 82% (14/17) and specificity of 83% (5/6). The addition of stressors improved specificity considerably. Cut-offs, statistics and rules are clearly discussed to facilitate the use of this assay for screening purposes. Overall, the authors consider that this assay should be part of the battery of safety screening assays at early stages of drug development.

Rates and multiple sulfur isotope fractionations associated with the oxidation of sulfide by oxygen in aqueous solution

Sulfide oxidation is a major component of the global sulfur cycle that requires consideration in isotope-based models of aquatic and sedimentary systems, but the isotope fractionations based on analyses of all three isotope ratios of sulfur (33S/32S, 34S/32S, 36S/32S) have yet to be documented for abiological sulfide oxidation processes. We present experimental determinations of the reaction rates and sulfur isotope fractionations associated with the oxidation of aqueous sulfide (principally HS−) by molecular oxygen (‘autoxidation’) in high pH (≈9.8), low ionic strength carbonate/bicarbonate buffered solutions as a function of temperature (5–45 °C) and trace metal catalysis (ferrous iron, added [Fe2+] ∼50–150 nM). Rates and isotope fractionations are quantified via the analysis of sulfide as a function of reaction progress over relatively low extents of reaction (ca. 33–47%). The oxidation of sulfide at pH = 9.8 and 25 °C without any catalyst added is associated with a computed second order rate constant (k) of lnk = 3.49 ± 0.38 (k in M−1 hr−1; 2 s.d., quadruple experiments) and major sulfur isotope discrimination of 34εP-R = −5.85 ± 0.43‰ (2 s.d., duplicate experiments) that are both consistent with previous studies, and a corresponding minor sulfur isotope fractionation relationship of 33/34θ = 0.509 ± 0.004 that translates to Δ33SP-R = 0.033 ± 0.018‰ (2 s.d.). The dependence of 34εP-R on reaction rate due to either temperature or ferrous iron catalysis over the ranges we have studied is small (<∼1‰ in 34εP-R) and similar values for 33/34θ and Δ33SP-R are obtained for all conditions studied (e.g., mean of all 7 experiments: 33/34θ = 0.5082 ± 0.0031 and Δ33SP-R = 0.037 ± 0.014‰; 2 s.d.). These results indicate that the process of sulfide autoxidation has a mass dependence that is resolvable from the expectations of typical equilibrium isotope exchange. Values for 36/34θ and Δ36SP-R may also exhibit deviations from typical equilibrium isotope exchange but are not resolved under all conditions studied. The shift in values of 33/34θ and Δ33S (and potentially 36/34θ and Δ36S) is consistent with the hypotheses that kinetic isotope effects can be associated with different mass laws than equilibrium processes or with reversibility occurring in the initial parts of the reaction network leading to oxidation products, but both hypotheses will likely require further investigation. We provide an example of how our experimentally calibrated ‘signature’ for sulfide autoxidation may be identified in natural data using the previously published δ34S and Δ33S values of dissolved sulfide in proximity to the oxic-sulfidic interface in the water column of the Cariaco Basin. The observation that the autoxidation of aqueous sulfide in high pH media is associated with a non-zero Δ33SP-R will influence how chemical oxidation processes are treated in environmental and global scale models of the sulfur cycle based on multiple sulfur isotopes.

English

Amylase enzymes are industrially important enzymes used in food, sugar, textile, pharmaceutical, paper and detergent industries. The main objective of this study was to isolate, produce and optimize α-amylase enzyme using a fungal strain isolated from fruit peel soil wastes. Media optimization was done by one-factor at a time method. Average values of duplicate experiments were taken. Microsoft office Excel worksheet 2010 was used for data analysis. Soil samples were collected from three places and a total of 89 fungal isolates were isolated. All isolates were screened for their potential to produce amylase based on the clear zone formation on starch agar media, of which isolate FAB-211 showed the maximum potential to produce amylase and considered for further study. The isolate was further characterized based on colony morphology and microscopic mount and the isolate FAB-211 was Aspergillus niger. Important process parameters affecting amylase activity with the fungal isolate were optimized. The maximum activity (0.483 U/ml) was observed at pH of 6.0 and temperature at 45°C was found to be the best for amylase activity (1.241 U/ml). The highest and least alpha-amylase production was found when 6 and 2 discs spore of A. niger FAB-211 were used, respectively. Maximum yield of alpha amylase (0.281 U/ml) was observed on the 3rd day of incubation period followed by 4, 6 and 5th days. Maltose and yeast extract were found to be the best carbon and nitrogen sources, respectively. Therefore, further optimization of parameters and characterization of A. niger FAB-211 amylase is important for their application in industries. Key words: Fungi, amylase enzyme, Aspergillus niger, FAB-211.

A Simple Emulsification-Assisted Extraction Method for the GC–MS/SIM Analysis of Wine Markers of Aging and Oxidation: Application for Studying Micro-Oxygenation in Madeira Wine

Sotolon and the heterocyclic acetals of glycerol are known as potential aging and oxidation markers in fortified wines such as Madeira, Port, and Sherry. Thus, determining the evolution of these compounds under different oxidative aging conditions is important for fortified wine quality purposes. This study proposes a new methodology based on a miniaturized emulsification extraction followed by GC–MS/SIM, which was developed and optimized to follow the formation of sotolon and heterocyclic acetals in fortified wines that were submitted to traditional accelerated aging and micro-oxygenation. The optimization was achieved by means of a mixed-level factorial design, considering 3 factors: sample volume, extractant volume, and concentrated extract volume, by performing 19 experiments in duplicate. The extraction was optimized using 8 mL of wine sample, 5 mL of dichloromethane, concentrating the extract up to 10-fold. The method performance was evaluated for sotolon, using a matrix-matched calibration between 10 and 2000 μg/L. The selectivity was confirmed through the analysis of real samples. The methodology showed good linearity (R2 = 0.999), high sensitivity (LOQ = 6.8 μg/L), recovery about 105%, and good precision (less than 8 and 9%, evaluated by the variation of intra- and inter-day measurements, respectively). This is the first methodology that revealed to be an excellent tool to simultaneously follow the formation of sotolon and heterocyclic acetals in Madeira wines, using an inexpensive, simple, efficient, and effective experimental layout. Indeed, it was shown that traditional accelerated aging and micro-oxygenation have impact on the formation of such molecules.

Clearance of ceftazidime-avibactam in an in vitro continuous venovenous hemodialysis model

Abstract Background Optimal dosing of ceftazidime-avibactam (C-A) in critically ill patients on continuous renal replacement therapy (CRRT) is unknown. The objective of this study was to evaluate the adsorption and transmembrane clearance (CLTM) of C-A in an in vitro continuous venovenous hemodialysis (CVVHD) model to guide dosing in the absence of clinical data. Methods CVVHD was simulated with bovine blood (200 mL/minute) on a Prismaflex dialysis unit with polysulfone (HF1400) and AN69 (M150) hemofilters at dialysate flow rates (Qd) of 2 and 4 L/hours. Pre-hemofilter plasma samples were collected at 0, 5, 10, 20, 30, 45, and 60 mins after C-A addition; postfilter and dialysate samples were collected at 10 and 45 mins for saturation coefficient (SA) calculation. Adsorption was determined by total drug recovery in dialysate and plasma after 120 mins of dialysis at 2 L/hours. CLTM was calculated as the product of SA and Qd (CLTM-SA) and by elimination rate constant (CLTM-ke) derived from the slope of log-linear concentration-time plots. Results Mean (± SD) SA and CLTM values for C-A from duplicate experiments are in Table 1. CLTM was not affected by filter type, and increased linearly with Qd when calculated by two different methods. Avibactam CLTM was higher than ceftazidime CLTM with each filter and rate. Adsorption affected 17.3% and 20.2% of C-A for HF1400 and AN69 filters, respectively. Conclusion Significant Qd- dependent clearance of C-A was observed in in vitro CVVHD. CLTM of ceftazidime was slightly higher than previous reports and may reflect the larger surface area of contemporary filters in this study. The more rapid clearance of avibactam, particularly at higher flow rates, suggests that dose adjustments should focus on ensuring adequate avibactam exposure during CVVHD. Disclosures L. H. Danziger, Allergan: Investigator, Research grant.

First Report of Streptomyces turgidiscabies Causing Potato Common Scab in Spain

Potato common scab (CS) is an important crop problem worldwide. Previously, Streptomyces europaeiscabies has been considered as a predominant pathogen in the west European region. Potato (Solanum tuberosum) samples having visible CS symptoms were collected from Galicia, Spain, during 2015. Potato samples were heavily infected with CS symptoms from superficial netted scab to pitted lesions. Samples were washed with tap water before and after disinfecting with 2.8% sodium hypochlorite for 1 min. Scab lesions on the surface of infected potatoes were used to isolate Streptomyces colonies (Wanner 2006). During the survey, more than 25 Streptomyces isolates were identified as pathogenic to potatoes from different regions of Spain (data not shown). Streptomyces isolate strain AC-51 was identified after morphological and physiological characterization as S. turgidiscabies (Bouchek-Mechiche et al. 2006). Pure colonies of Streptomyces were cultured in tryptic soy broth (TSB). A Streptomyces pellet was used for genomic DNA extraction by Fast DNA kit (MP Biomedicals, U.S.A.). Purified DNA was amplified for 16S rRNA gene by using pH/pA primers (Edwards et al. 1989). The resultant 16S rDNA sequences were submitted to GenBank. NCBI BLAST analysis of S. turgidiscabies strain AC-51 (LN908786) showed 97% similarity with S. turgidiscabies (FJ546740). Streptomyces spp. was further characterized by performing a positive PCR reaction with S. turgidiscabiei-specific primers Tur-R/F (Tagawa et al. 2008) but had negative reaction with individual species-specific primers from S. scabies, S. europaeiscabies, S. stelliscabies, S. bottropensis, and S. acidiscabies (Wanner 2006). A pathogenicity island consisting of txtAB, nec1, and tomA genes was confirmed in S. turgidiscabies strain AC-51 by using different PCR primers (Bukhalid et al. 1998; Wanner 2006). The pathogenicity of strain AC-51 was tested on potatoes by pot assay in a greenhouse facility. Potato tubers (cv. Kennebec) were planted in potting soil (Compo Sana, Germany) with an average temperature maintained between 25 and 28°C. Cell suspension of strain AC-51 was prepared at concentration of 106CFU/ml. Three-week-old potato plants were drenched with 100 ml of prepared inoculum in duplicate experiments. To validate the experimental results, nonpathogenic Streptomyces sp. (KU560918) and pathogenic S. scabies RL-34 (kindly provided by Dr. J. Leiminger, DSMZ41658) were used in the same concentration as negative and positive controls, respectively. Three-month-old plants were harvested and CS symptoms on potato surface were recorded. Disease symptoms were observed from moderate to high pitted scab lesions among the pots infected with S. turgidiscabies strain AC-51 and S. scabies (Wanner 2006), while no CS symptoms were observed with nonpathogenic Streptomyces spp. Disease severity was recorded as mean surface area covered by CS symptoms as 32% for strain AC-51, 38% for S. scabies, and 0% for nonpathogenic Streptomyces spp. Pathogenic S. turgidiscabies strain AC-51 was again isolated from infected tubers in greenhouse study to confirm Koch’s postulates. To our knowledge, this is the first report of S. turgidiscabies in Galicia, Spain. This study will provide a basic knowledge about the pathogens which will helpful to develop preventive strategies against this disease.

FD5180, a Novel Protein Kinase Affinity Probe, and the Effect of Bead Loading on Protein Kinase Identification.

The effects of compound loading on the identification of protein kinases (PKs) was examined using two previously reported sepharose-supported PK inhibitors (PKIs): bisindolylmaleimide X (S1) and CZC8004 (S2). Compound loadings of 0.1, 0.5, 2.5, 5, 10, 25, and 50% content and an ethanolamine-blocked control bead (no compound) were investigated. A 50% bead loading gave the highest level of PK identification for both S1 and S2, extracting 34 and 55 PKs, respectively, from a single cell lysate. Control beads allowed overall identification of 23 PKs, which we term the kinase beadome, whereas sepharose-supported sunitinib (S7; 50% loading) identified 20, 11 of which were common to the control beads. The reliability of bead pull-downs was examined in duplicate experiments using two independently synthesized batches each of S1 and S2. Bead S1 showed high similarity in the absolute numbers of PKs identified across two experiments, at 40 and 35 PKs, of which 26 were common across the two batches of beads, with 14 and 9 unique PKs identified in each experiment. The S2 beads extracted 61 and 64 PKs with 55 PKs common across the two bead batches examined. We also report on the development and use of a novel promiscuous PKI analogue, 2-[(5-chloro-2{[4-(piperazin-1-yl)phenyl]amino}pyrimidin-4-yl)amino]-N-methylbenzene-sulfonamide (S15), which extracted 12 additional unique PKs over the two parent compounds from which it was designed, the combination of which identifies 160 unique PKs. S15 was based on the common pyrimidine core scaffold of S9 and S10. Thus, S15 expands the utility of kinobeads by broadening the kinome coverage for bead-based pull-down. Combining the data for all beads across 90 and 180 min liquid chromatography–mass spectrometry (LC–MS)/MS analysis identified a total of 160 unique PKs.

A reproducible microcosm biofilm model of subgingival microbial communities.

To develop a reproducible subgingival microcosm biofilm model. Subgingival plaque samples were collected from four deep pockets (probing pocket depth ≥6mm) in each of seven patients with periodontitis and from shallow pockets (probing pocket depth ≤3mm) in two periodontally healthy donors. An active attachment model and a peptone medium (Thompson et. al., Appl Environ Microbiol 2015;81:8307-8314) supplemented with 30% serum was used. Biofilms were harvested at 2 and 4weeks. DNA of dead cells was blocked for amplification by propidium monoazide treatment. Composition was analyzed using 16S rRNA gene amplicon pyrosequencing. Similarities between the biofilm samples were assessed by non-metric multidimensional scaling using the Bray-Curtis similarity index and similarity percentage analysis. Data from duplicate experiments, different biofilm sources and different biofilm age were compared. The non-metric multidimensional scaling revealed a strong clustering by the inoculum source, the donor and their periodontal status. Statistically significant differences were found between the sources of inoculum (P=.0001) and biofilm age (P=.0016). Furthermore, periodontitis biofilms (P) were distinct in composition from health-derived biofilms (H) by genera: Porphyromonas (P=19%; H=0%), Filifactor (P=10%; H=0%), Anaeroglobus (P=3%; H=0%), Phocaeicola (P=1.5%; H=0%), Parvimonas (P=19%; H=14%), Fusobacterium (P=2%; H=26%), Peptostreptococcus (P=20%; H=30%), Veillonella (P=7%; H=8%) and 57 other genera. Similarity distances (Bray-Curtis) (mean 0.73, SD 0.15) and the Shannon diversity index (mean 2, SD 0.2) revealed no differences between duplicate experiments (P=.121). This biofilm model allows reproducible production of complex subgingival microbial communities.

Abstract 4: Inhibitory effects of aprotinin on survival and local invasion of human breast cancer cell lines

Abstract Background: Aprotinin is a nonspecific serine protease inhibitor, which can inhibit kallikrein and many downstream extracellular matrix degrading enzymes. In this study, we assessed inhibitory effects of aprotinin on local invasion of human breast cancer cell lines. Methods: We assessed effects of aprotinin on local invasion and survival of human breast cancer cell lines MDA-MB231 and SK-BR-3 in vitro. CHEMICON Cell Invasion Assay Kit was used to assess local invasion of tumoral cells. MTT assay was used to determine the anti-proliferative activity of aprotinin on different cancer cell lines. Mean optical densities of duplicate experiments were calculated for both assays. HDF-1 human fibroblast cell line was used as control normal cell. In addition, local invasion and survival of tumor cell lines treated with aprotinin were compared with untreated experiments. Results: Cancer cell lines showed more invasion compared to HDF-1. Aprotinin significantly decreased the invasiveness of MDA-MB231 in concentration of 1 TIU/ml, 1.3 TIU/ml, and 1.7 TIU/ml in comparison with untreated group (ANOVA P &amp;lt;0.001). Treatment of SK-BR-3 with 1.3 TIU/ml aprotinin trended towards reduction of invasion optical density (P = 0.06). Treatment with different concentrations of aprotinin significantly decreased the surviving fraction and significantly inhibited the growth of all cell lines tested in this study (ANOVA P &amp;lt;0.001). Conclusion: Aprotinin inhibited the survival and local invasion of human breast cancer cell lines MDA-MB231 and SK-BR-3. Although the growth inhibitory effect was significant in both cell lines, inhibition of local invasion was more pronounced in case of MDA-MB231. Future molecular studies could shed further lights on mechanisms underlying anti-neoplastic effects of aprotinin and its potential therapeutic effects. Citation Format: Saeed Soleyman-Jahi, Kazem Zendehdel, Fatemeh Sadeghi, Ziba Afshari, Tahereh Barati, Samad Mohammadnezhad, Sevil Ghasemi, Saeed Amanpour. Inhibitory effects of aprotinin on survival and local invasion of human breast cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4. doi:10.1158/1538-7445.AM2017-4

Analysis of protein complexes in Arabidopsis leaves using size exclusion chromatography and label-free protein correlation profiling

Protein complexes are fundamentally important for diverse cellular functions, and create functionalities that could never be achieved by a single polypeptide. Knowledge of the protein complex assemblies that exist in plant cells are limited. To close this gap, we applied an integrative proteomic approach that combines cell fractionation, protein chromatography and quantitative mass spectrometry (MS) to analyze the oligomerization state of thousands of proteins in a single experiment. Soluble extracts from intact Arabidopsis leaves were fractionated using size exclusion chromatography (SEC), and abundance profiles across the column fractions were quantified using label-free precursor ion (MS1) intensity. In duplicate experiments, we reproducibly detected 1693 proteins, of which 983 proteins were cytosolic. Based on the SEC profiles, approximately one third of all of the soluble proteins were predicted to be oligomeric. Our dataset includes both subunits of previously known complexes as well as hundreds of new protein complexes. The label-free MS1-based quantification method described here produced a highly useful dataset for the plant biology community, and provided a foundation to incorporate orthogonal protein complex separation methods so the composition and dynamics of protein complexes can be analyzed based on LC/MS profile data alone.

Nonlinear responses to waterborne cadmium exposure in zebrafish. An in vivo study

Cadmium (Cd) has proved to be associated with numerous toxic effects in aquatic organisms via waterborne exposure. With a view to investigate Cd toxicity along a broad spectrum of exposures reaching from environmental to toxic, we employed adult zebrafish (Danio rerio) for an in vivo study. A number of 10 fish per tank were placed in 40L tanks and were exposed for 30 days to 0.0, 5.0, 25, 50, 75, 100 and 1000μgCd per liter. There were 2 tanks for each Cd exposure (duplicate experiment). Mortality was recorded daily, dead fish were collected and tissue samples were obtained for histologic observation, whereas remaining tissues were stored for Cd burden determination. Surviving fish were collected at the end of the experiment. Median overall survival (OS) in days was found to be 9.0, 11.0, 8.0 and 7.0 for 25μg/L, 50μg/L, 75μg/L and 100μg/L respectively, with all of them showing mortality greater than 50%. Remarkably, fish exposed to the highest Cd concentration (1000μg/L) survived the longest exhibiting a mean OS of 29.2 days. Cd determination in fish tissue was conducted with an in house ICP-MS method and levels ranged from 3.1 to 29.1ng/mg. Log Cd tissue levels were significantly correlated with the log Cd exposure levels (r = 0.535, p < 0.001). The highest Cd burden was determined for fish exposed to 1000μgCd /L (mean = 12.2ng/mg). Histopathology supported these results. Our findings disclose a deviation in toxic responses through the range of Cd concentrations, leading to nonlinear responses. These differentiated responses, could be linked to hormesis phenomena.

PNFLBA-05 POLYURETHANES FOR URINARY STENTS: A STUDY ON MATERIALS’ STONE ENCRUSTATION PERFORMANCES

You have accessJournal of UrologyPlenary: Next Frontier (PNFLBA)1 Apr 2017PNFLBA-05 POLYURETHANES FOR URINARY STENTS: A STUDY ON MATERIALS’ STONE ENCRUSTATION PERFORMANCES Gary Li, Jun Li, Zheng Zhang, and Morgan Tierney Gary LiGary Li More articles by this author , Jun LiJun Li More articles by this author , Zheng ZhangZheng Zhang More articles by this author , and Morgan TierneyMorgan Tierney More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.03.069AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Many studies have looked at infection and encrustation resistance capabilities of commercial ‘polyurethane’ (PU) compared to silicone [Tunney et al., 1996; Gorman et al., 1998; Bithles, 2004], but few have specified the exact PU composition [Park et al., 2002] and none have considered multiple subtypes. The objective of this study was to determine the amount of encrustation formed on multiple PU subtypes compared to silicone. METHODS A continuous flow in vitro model of the bladder was built and validated, and the widely accepted artificial urine formulation by Tunney et al was chosen [5]. Experiments were done in duplicate, testing commercial polycarbonate PU, polyether PU, and polyester PU against silicone, the gold standard (n = 4). Over five days with daily solution refresh, measurements for calcium encrustation content were taken via o-Cresolphthalein (oCPC) method. One-way ANOVA and Fisher's Pairwise Comparison were used for statistical analysis. RESULTS Results showed significant reductions of encrustation on polyether PU and polyester PU compared to silicone (p-values < .0001) and similar levels of encrustation on polycarbonate PU compared to silicone (p-values < .510). CONCLUSIONS This study showed how polycarbonate PU encrusted much more than polyether and polyester PU, though all three are called ‘polyurethane.’ Furthermore, results suggest polyester and polyether PU perform better than silicone in terms of encrustation resistance. Future work includes clinical trials to confirm results. Note: The first experiment was done before the submission deadline and the duplicate experiment was done after the submission deadline to confirm findings. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e604-e605 Advertisement Copyright & Permissions© 2017MetricsAuthor Information Gary Li More articles by this author Jun Li More articles by this author Zheng Zhang More articles by this author Morgan Tierney More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Layered clays in PP polymer dispersion: the effect of the processing conditions

ABSTRACTThe effect of processing conditions of material and interfacial/ interphase properties in clay/polymer nanocomposites are usually studied through experimental results of X-ray diffraction, transmission electron microscopy and rheology mechanical tests. In this paper, the interaction of the experimental parameters and properties measure results are studied by employing multivariate analysis of variance technique. This model is used to establish relations between several material and interfacial/interphase characteristics with the processing conditions. These results are then analyzed in detail, using univariate approach (analysis of variance), to point out the existing significant relations. In general, agreement with experimental observations was found, but few other nonagreeable things are found out, which must be studied in the future. The effects of all parameters are thus determined, using these new approach, to predict the relations between material and interfacial/interphase properties, without the need to duplicate experiments in laboratory.

KINETIC EVALUATION OF ETHANOL-TOLERANT THERMOPHILE Geobacillus thermoglucosidasius M10EXG FOR ETHANOL PRODUCTION

Thermophiles are challenging to be studied for ethanol production using agricultural waste containing lignocellulosic materials rich in hexose and pentose. These bacteria have many advantages such as utilizing a wide range of substrates, including pentose (C5) and hexose (C6). In ethanol production, it is important to use ethanol tolerant strain capable in converting lignocellulosic hydrolysate. This study was aimed to investigate the growth profile of ethanol-tolerant thermophile Geobacillus thermoglucosidasius M10EXG using a defined growth medium consisted of single carbon glucose (TGTV), xylose (TXTV), and a mixture of glucose and xylose (TGXTV), together with the effect of yeast extract addition&lt;br /&gt;to the media. The experiments were conducted at the School of Biotechnology and Biomolecular Sciences of The University of New South Wales, Australia on a shake flask fermentation at 60°C in duplicate experiment. Cultures were sampled every two hours and analised for their kinetic parameters including the maximum specific growth rate (µmax), biomass yield (Yx/s), ethanol and by-product yields (acetate and L-lactate) (Yp/s), and the doubling time (Td). Results showed that this strain was capable of growing on minimal medium containing glucose or xylose as a single carbon source. This strain utilized glucose and xylose simultaneously (co-fermentation), although there was glucose repression of xylose at relatively low glucose concentration (0.5% w/v), particularly when yeast extract (0.2% w/v) was added to the medium. The highest biomass yield was obtained at 0.5 g l-1 on glucose medium; the yield increased when yeast extract was added (at 0.59 g l-1). The highest specific growth rate of 0.25 was obtained in the phase I growth when the strain was grown on a mixture of glucose and xylose (0.5% : 0.5% w/v) medium. Diauxic growth was shown on the mixture of glucose, xylose, and yeast extract. The strain produced low level of ethanol (0.1 g l-1), as well as low level (0.2 g l-1) of by-products (L-lactate and acetate) after 15 hours. The results suggests its potential application for fermenting lignocellulosic agricultural wastes for ethanol production.

KINETIC EVALUATION OF ETHANOL-TOLERANT THERMOPHILE Geobacillus thermoglucosidasius M10EXG FOR ETHANOL PRODUCTION

Thermophiles are challenging to be studied for ethanol production using agricultural waste containing lignocellulosic materials rich in hexose and pentose. These bacteria have many advantages such as utilizing a wide range of substrates, including pentose (C5) and hexose (C6). In ethanol production, it is important to use ethanol tolerant strain capable in converting lignocellulosic hydrolysate. This study was aimed to investigate the growth profile of ethanol-tolerant thermophile Geobacillus thermoglucosidasius M10EXG using a defined growth medium consisted of single carbon glucose (TGTV), xylose (TXTV), and a mixture of glucose and xylose (TGXTV), together with the effect of yeast extract addition&lt;br /&gt;to the media. The experiments were conducted at the School of Biotechnology and Biomolecular Sciences of The University of New South Wales, Australia on a shake flask fermentation at 60°C in duplicate experiment. Cultures were sampled every two hours and analised for their kinetic parameters including the maximum specific growth rate (µmax), biomass yield (Yx/s), ethanol and by-product yields (acetate and L-lactate) (Yp/s), and the doubling time (Td). Results showed that this strain was capable of growing on minimal medium containing glucose or xylose as a single carbon source. This strain utilized glucose and xylose simultaneously (co-fermentation), although there was glucose repression of xylose at relatively low glucose concentration (0.5% w/v), particularly when yeast extract (0.2% w/v) was added to the medium. The highest biomass yield was obtained at 0.5 g l-1 on glucose medium; the yield increased when yeast extract was added (at 0.59 g l-1). The highest specific growth rate of 0.25 was obtained in the phase I growth when the strain was grown on a mixture of glucose and xylose (0.5% : 0.5% w/v) medium. Diauxic growth was shown on the mixture of glucose, xylose, and yeast extract. The strain produced low level of ethanol (0.1 g l-1), as well as low level (0.2 g l-1) of by-products (L-lactate and acetate) after 15 hours. The results suggests its potential application for fermenting lignocellulosic agricultural wastes for ethanol production.