A Comparison of Fresh Frozen vs. Formalin-Fixed,Paraffin-Embedded Specimens of Canine Mammary Tumors via Branched-DNA Assay

Mammary neoplasms are the tumors most affecting female dogs and women. Formalin-fixed, paraffin-embedded (FFPE) tissues are an invaluable source of archived biological material. Fresh frozen (FF) tissue is considered ideal for gene expression analysis. However, strategies based on FFPE material offer several advantages. Branched-DNA assays permit a reliable and fast workflow when analyzing gene expression. The aim of this study was to assess the comparability of the branched-DNA assay when analyzing certain gene expression patterns between FF and FFPE samples in canine mammary tumors. RNA was isolated from 109 FFPE samples and from 93 FF samples of different canine mammary tissues. Sixteen (16) target genes (Tp53; Myc; HMGA1; Pik3ca; Mcl1; MAPK3; FOXO3; PTEN; GATA4; PFDN5; HMGB1; MAPK1; BRCA2; BRCA1; HMGA2; and Her2) were analyzed via branched-DNA assay (b-DNA). ACTB, GAPDH, and HPRT1 were used as data normalizers. Overall, the relative gene expression of the two different origins of samples showed an agreement of 63%. Still, care should be taken, as FFPE specimens showed lower expression of the analyzed targets when compared to FF samples. The fact that the gene expression in FFPE proved to be lower than in FF specimens is likely to have been caused by the effect of storage time. ACTB had the best performance as a data normalizer.     

Blends of Two Perylene Derivatives: Mesogenic Properties and Application As Emitter Materials in OLEDs

Blends consisting of two components, namely a liquid crystalline perylene ester and a bilaterally extended perylene ester, were studied. The liquid crystalline properties of these blends were investigated in detail by means of polarized optical microscopy and differential scanning calorimetry. The resulting phase diagram was used to explore the potential of these blends as emitter layers in OLEDs, which were prepared via thermal evaporation in a vacuum and spin coating of solutions.     

Druids' Knowledge in Chemical Engineering: Analysis of the Illustrated Literature by Goscinny and Uderzo

The illustrated literature series Asterix (and Obelix) is commonly known as entertainment and distraction, but behind that mask, case studies for chemical production in small medium enterprises and the crucial role of research and development can be discovered. The series rightly puts chemistry and chemical engineering at the heart of success and prosperity. Overall, the motives exemplified are of high relevance today for chemical industry.     

Different Enzymatic Processing of γ‐Phosphoramidate and γ‐Phosphoester‐Modified ATP Analogues

Monitoring the activity of ATP‐consuming enzymes provides the basis for elucidating their modes of action and regulation. Although a number of ATP analogues have been developed for this, their scope is restricted because of the limited acceptance by respective enzymes. In order to clarify which kind of phosphate‐modified ATP analogues are accepted by the α‐β‐phosphoanhydride‐cleaving ubiquitin‐activating enzyme 1 (UBA1) and the β‐γ‐phosphoanhydride‐cleaving focal adhesion kinase (FAK), we tested phosphoramidate‐ and phosphoester‐modified ATP analogues. UBA1 and FAK were able to convert phosphoramidate‐modified ATP analogues, even with a bulky modification like biotin. In contrast, a phosphoester‐modified analogue was poorly accepted. These results demonstrate that minor variations in the design of ATP analogues for monitoring ATP utilization have a significant impact on enzymatic acceptance.     

Detection near 1-nm with a laminar-flow,water-based condensation particle counter

Presented is a laminar-flow, water-based condensation particle counter capable of particle detection near 1 nm. This instrument employs a three-stage, laminar-flow growth tube with a “moderator” stage that reduces the temperature and water content of the output flow without reducing the peak supersaturation, and makes feasible operation at the large temperature differences necessary for achieving high supersaturations. The instrument has an aerosol flow of 0.3 L/min, and does not use a filtered sheath flow. It is referred to as a “versatile” water condensation particle counter, or vWCPC, as operating temperatures can be adjusted in accordance with the cut-point desired. When operated with wall temperatures of ～2°C, >90°C, and ～22°C for the three stages, respectively, the vWCPC detects particles generated from a heated nichrome wire with a 50% efficiency cut-point near 1.6 nm mobility diameter. At these operating temperatures, it also detects 10–20% of large molecular ions formed from passing filtered ambient air through a bipolar ion source. Decreasing the temperature difference between the first two stages, with the first and second stages operated at 10 and 90°C, respectively, essentially eliminates the response to charger ions, and raises the 50% efficiency cut-point for the nichrome wire particles to 1.9 nm mobility diameter. The time response, as measured by rapid removal of an inlet filter, yields a characteristic time constant of 195 ms.

Copyright © 2017 American Association for Aerosol Research     

Multi-photon imaging of amine-functionalized silica nanoparticles

A convenient and simple strategy for preparing water soluble, photoluminescent functionalized silica nanoparticles (M-dots) in the absence of fluorophores or metal doping is demonstrated. These M-dots can be used for bioimaging using one and two-photon microscopy. Because of their high photostability, low toxicity and high biocompatibility compared with Lumidot? CdSe/ZnS quantum dots, functionalized silica particles are superior alternatives for current bioimaging platforms. Moreover, the presence of a free amine group at the surface of the M-dots allows biomolecule conjugation (e.g. with antibodies, proteins) in a single step for converting these photoluminescent SiO(2) nanoparticles into multifunctional efficient vehicles for theragnostics.     

Effects of dietary α-linolenic acid on the conversion and oxidation of13C-α-linolenic acid

The effects of a diet rich in α-linolenic acid vs. one rich in oleic acid on the oxidation of uniformly labeled¹³C-α-linolenic acid and its conversion into longer-chain polyunsaturates (LCP) were investigatedin vivo in healthy human subjects. Volunteers received a diet rich in oleic acid (n=5) or a diet rich in α-linolenic acid (n=7; 8.3 g/d) for 6 wk before and during the study. After 6 wk, subjects were given 45 mg of¹³C-α-linolenic acid dissolved in olive oil. Blood samples were collected att=0, 5, 11, 24, 96, and 336 h. Breath was sampled and CO₂ production was measured each hour for the first 12 h. The mean (±SEM) maximal absolute amount of¹³C-eicosapentaenoic acid (EPA) in plasma total lipids was 0.04 ±0.01 mg in the α-linolenic acid group, which was significantly lower (P=0.01) than the amount of 0.12±0.03 mg¹³C-EPA in the oleic acid group. Amounts of¹³C-docosapentaenoic acid (DPA) and¹³C-docosahexaenoic acid (DHA) tended to be lower as well. The mean proportion of labeled α-linolenic acid (ALA) recovered as¹³CO₂ in breath after 12 h was 20.4% in the ALA and 15.7% in the oleic acid group, which was not significantly different (P=0.12). The cumulative recovery of¹³C from¹³C-ALA in breath during the first 12 h was negatively correlated with the maximal amounts of plasma¹³C-EPA (r=−0.58,P=0.047) and¹³C-DPA (r=−0.63,P=0.027), but not of¹³C-DHA (r=−0.49,P=0.108). In conclusion, conversion of¹³C-ALA into its LCP may be decreased on diets rich in ALA, while oxidation of¹³C-ALA is negatively correlated with its conversion into LCP. In a few pilot samples, low¹³C enrichments of n−3 LCP were observed in a diet rich in EPA/DHA as compared to oleic acid.     

Results of an inter-laboratory comparison of methods for quantitative clay analysis

In a comparison of analytical methods in clay mineralogy, two clay samples (from Hennersdorf and Freydegg) of different clay composition were analyzed by 19 laboratories mainly by XRD. Participants used different methods of pre-treatment, preparation, analysis and evaluation.In spite of the diversity of analytical methods applied, reasonable conformity in quantitative results was obtained for the associated minerals (quartz, calcite and dolomite). On the other hand, qualitative identification of the clay minerals showed considerably stronger divergencies, causing a stronger deviation of quantitative data; analysis of the Freydegg sample proved to have been particularly difficult. The evaluation methods of the different participants were examined to determine whether similar methods provided results that could be more easily compared.In addition, the authors calculated the clay mineral composition according to three different recognized methods, using the same diffractograms and same preparation and measuring conditions. In spite of this, different results were obtained.In the next phase of the programme, an inter-laboratory comparison of methods will be achieved under exactly defined conditions of preparation and analysis.     

In vitro and in vivo Staining Characteristics of Small,Fluorescent, Aβ42‐Binding D‐Enantiomeric Peptides in Transgenic AD Mouse Models

Plaque visualisation : We identified three different D ‐enantiomeric peptides that bind to Alzheimer's amyloid β (Aβ1‐42). As there is currently no definitive pre‐mortem diagnosis for Alzheimer's disease, we investigated the peptides' suitability as molecular probes for in vivo imaging in transgenic mouse models.