Iron sulfide formation on root surfaces controlled by the life cycle of wild rice (<Emphasis Type="Italic">Zizania palustris</Emphasis>)

Iron sulfide plaques have been observed on roots of wild rice (Zizania palustris) and other wetland plants grown in sulfur-impacted freshwater ecosystems, but the mechanism of their formation and ramifications for plants have not been investigated. We exposed a model annual wetland plant, Zizania palustris, to elevated sulfate concentrations (3.1 mM) and quantified the development of iron oxide and iron sulfide precipitates on root surfaces throughout the plant life cycle. During the onset of seed production, root surfaces amended with sulfate transitioned within 1 week from iron (hydr)oxide plaques to iron sulfide plaques. During the same week, Fe(III) decreased on roots of plants not amended with sulfate but FeS did not accumulate. Prior to FeS accumulation, sulfate-amended plants had taken up the same amount of N as unamended plants. After FeS accumulation, total plant nitrogen did not increase further on sulfate-amended plants, indicating a cessation in nitrogen uptake, whereas total plant N continued to increase in unamended plants. Sulfate-amended plants produced fewer and lighter seeds with less nitrogen than unamended plants. FeS precipitation on roots may be associated with elevated sulfide and inhibited nitrogen uptake before the end of the plant’s life cycle, thus affecting the populations of this annual aquatic plant. We propose a mechanism by which a physiologically-induced decline in radial oxygen loss near the end of a plant’s life cycle initiates a precipitous decline in redox potential at the root surface and in adjacent porewater, initiating accumulation of iron sulfide plaques. These plaques could be an important locus for iron sulfide accumulation in wetland sediments.     

The survival of rat cerebral cortical neurons in the presence of trophic APP peptides

One function of Alzheimer amyloid protein precursor (APP) is the regulation of growth and differentiation in several types of cells, including fibroblasts, PC12 cells, and neurons. This activity is represented by a small stretch of amino acids in the center of the molecule around RERMS. The APP 17-mer peptide containing the RERMS domain supported survival and neurite extension of rat cortical neurons in a dose-dependent and sequence-specific manner. The APP fragment synthesized in Escherichia coli supported the survival and neurite extension of rat cortical neurons, whereas the mutant APP fragment lacking the 30 amino acids around the RERMS domain had drastically reduced activity to support the survival and neurite extension. The current study established APP as a neuron survival factor and determined that the sequence around RERMS is important for this function. © 1994 John Wiley & Sons, Inc.     

A phi Layer in Roots of Ceratonia siliqua L

The central cylinder of the primary root of the carob tree (Ceratonia siliqua) is encircled by a layer of cells with wall thickenings, known as a phi (φ) cell layer. The development of the φ layer and the chemical composition of the cell wall thickenings have been studied in roots of C. siliqua. The results reveal the presence of condensed tannins in the mature phi thickenings and that the development of the φ layer is asynchronous: at 0–1 cm from the root tip φ thickenings appear before endodermis differentiation at the sites opposite phloem, at 1–4 cm new φ thickenings are developed at the sites opposite xylem, at 4–7 cm the φ layer consists of two layers of cells and it completely encloses the central cylinder.     

Highly potent activity of isopulegol-derived substituted octahydro-2H-chromen-4-ols against influenza A and B viruses

A set of (?)-isopulegol derived octahydro-2H-chromen-4-ols was synthesized and evaluated in vitro for antiviral activity against panel of reference influenza virus strains differing in subtype, origin (human or avian) and drug resistance. Compound (4R)-11a produced via one-pot synthesis by interaction between (?)-isopulegol and acetone was found to exhibit an outstanding activity against a number of H1N1 and H2N2 influenza virus strains with selectivity index more than 1500. (4R)-11a was shown to be most potent at early stages of viral cycle. Good correlation between anti-viral activity and calculated binding energy to hemagglutinin TBHQ active site was demonstrated.     

Seasonal changes in blood biochemical and endocrine responses of different indigenous goat breeds of tropical island agro-ecological environment

The objective of the current study was to observe the impact of two seasons viz. summer (February–May) and monsoon (June–August) on the blood biochemical and hormonal responses in different indigenous goats of tropical island agro-ecological environment maintained under extensive management system. Sixty animals of three different indigenous goat breeds were included in the study: Andaman local goat (AL, n = 20), Andaman local?×?Malabari (AL?×?M, n = 20), and Teressa goat (n = 20). Sixty serum samples (n = 10/season/breed) from the three groups of animals were analyzed. Study revealed that there was a significant increase (p ≤ 0.05) in serum total protein in Teressa goats during summer than monsoon. Serum albumin showed significant variation (p ≤ 0.05) between AL and AL?×?M during summer whereas significant variation of albumin (p ≤ 0.05) was observed between AL and Teressa, AL?×?M and Teressa during monsoon season. Significant differences in serum albumin (p ≤ 0.05) were also observed in AL and AL?×?M during summer and monsoon seasons, respectively. The serum cortisol levels were significantly higher (p ≤ 0.05) in AL goats during summer than in monsoon season. Thus, the study could able to establish the seasonal variation in biochemical and hormonal values of indigenous goat breeds in hot and humid tropical island environment.     

Intracellular response to process optimization and impact on productivity and product aggregates for a high‐titer CHO cell process

A key goal in process development for antibodies is to increase productivity while maintaining or improving product quality. During process development of an antibody, titers were increased from 4 to 10 g/L while simultaneously decreasing aggregates. Process development involved optimization of media and feed formulations, feed strategy, and process parameters including pH and temperature. To better understand how CHO cells respond to process changes, the changes were implemented in a stepwise manner. The first change was an optimization of the feed formulation, the second was an optimization of the medium, and the third was an optimization of process parameters. Multiple process outputs were evaluated including cell growth, osmolality, lactate production, ammonium concentration, antibody production, and aggregate levels. Additionally, detailed assessment of oxygen uptake, nutrient and amino acid consumption, extracellular and intracellular redox environment, oxidative stress, activation of the unfolded protein response (UPR) pathway, protein disulfide isomerase (PDI) expression, and heavy and light chain mRNA expression provided an in‐depth understanding of the cellular response to process changes. The results demonstrate that mRNA expression and UPR activation were unaffected by process changes, and that increased PDI expression and optimized nutrient supplementation are required for higher productivity processes. Furthermore, our findings demonstrate the role of extra‐ and intracellular redox environment on productivity and antibody aggregation. Processes using the optimized medium, with increased concentrations of redox modifying agents, had the highest overall specific productivity, reduced aggregate levels, and helped cells better withstand the high levels of oxidative stress associated with increased productivity. Specific productivities of different processes positively correlated to average intracellular values of total glutathione. Additionally, processes with the optimized media maintained an oxidizing intracellular environment, important for correct disulfide bond pairing, which likely contributed to reduced aggregate formation. These findings shed important understanding into how cells respond to process changes and can be useful to guide future development efforts to enhance productivity and improve product quality.     

Usefulness of R-R interval and its variability in evaluation of thermal comfort

The use of R-R interval and the coefficient of variation in R-R intervals (CV_R-R) for the evaluation of thermal comfort was investigated. The experiments were carried out with ten male subjects but data from one were excluded from the analysis. Thermal sensation, comfort, and tolerance of environmental conditions were reported and mean skin temperature, R-R interval and CV_R-R were monitored during a 3 h period in a climatic chamber with the operative temperature set at 26, 20, or 30° C. Relative humidity was maintained at ca. 50% in each case. At the operative temperature of 20° C, the mean skin temperature was significantly lower, the cold sensation was significantly more intense, and discomfort was significantly greater than at 26° C and R-R interval was increased significantly. Seven of the nine subjects were unable to tolerate this thermal environment. The R-R interval and CV_R-R were increased in five and four of those seven subjects, respectively. At the operative temperature of 30° C, the mean skin temperature was significantly higher, and the sensation of warmth was significantly more intense than at 26° C. Seven of the nine subjects felt discomfort, and four of the seven reported an inability to tolerate this thermal environment. The R-R interval and CV_R-R were decreased in four and three of these four subjects, respectively. At the operative temperature of 20° C CV_R-R was significantly greater than that at 30° C. Together with the subjective indices, R-R interval and CV_R-R are considered worthy of further evaluation as objective indications of the effect on people of the thermal environment.     

Development of downstream processing to minimize beta‐glucan impurities in GMP‐manufactured therapeutic antibodies

The presence of impurities or contaminants in biological products such as monoclonal antibodies (mAb) could affect efficacy or cause adverse reactions in patients. ICH guidelines (Q6A and Q6B) are in place to regulate the level of impurities within clinical drug products. An impurity less often reported and, therefore, lacking regulatory guideline is beta‐glucan. Beta‐glucans are polysaccharides of d ‐glucose monomers linked by (1‐3) beta‐glycosidic bonds, and are produced by prokaryotic and eukaryotic organisms, including plants. They may enter manufacturing processes via raw materials such as cellulose‐based membrane filters or sucrose. Here we report the detection of beta‐glucan contamination of a monoclonal IgE antibody (MOv18), manufactured in our facility for a first‐in‐human, first‐in‐class clinical trial in patients with cancer. Since beta‐glucans have potential immunostimulatory properties and can cause symptomatic infusion reactions, it was of paramount importance to identify the source of beta‐glucans in our product and to reduce the levels to clinically insignificant concentrations. We identified beta‐glucans in sucrose within the formulation buffer and within the housing storage buffer of the virus removal filter. We also detected low level beta‐glucan contamination in two of four commercially available antibodies used in oncology. Both formulation buffers contained sucrose. We managed to reduce levels of beta‐glucan in our product 10‐fold, by screening all sucrose raw material, filtering the sucrose by Posidyne® membrane filtration, and by incorporating extra wash steps when preparing the virus removal filter. The beta‐glucan levels now lie within a range that is unlikely to cause clinically significant immunological effects. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1494–1502, 2016