Simultaneous Genotyping of Multiple Somatic Mutations by Using a Clamping PNA and PNA Detection Probes

It has been very difficult to detect and quantify multiple somatic mutations simultaneously in single‐tube qPCR. Here, a novel method for simultaneous detection of multiple mutations and a melting curve analysis was developed by using clamping PNA and detection PNA probes. Each PNA probe was designed to have a specific melting temperature by the introduction of γ‐PNA monomer. This technique was successfully applied to the detection of six genotypes in two different mutations of K‐RAS at the same time. Such simultaneous analysis of an amplified curve and a melting curve in qPCR can be widely used for the early diagnosis of cancer and determining the prognosis of drug treatments.     

Sex Pheromone of the Spanish Population of the Beet Armyworm <Emphasis Type=Italic>Spodoptera exigua</Emphasis>

The pheromone composition of the Spanish population of the beet armyworm (BAW), Spodoptera exigua (Lepidoptera: Noctuidae), was identified. Analysis of female gland extracts showed the presence of compounds Z9,E12–14:Ac (1), Z9–14:Ac (2), Z11–16:Ac (3), Z9,E12–14:OH (4), Z9–14:OH (5), and Z11–16:OH (6) in a ratio of 26:11:1:22:31:9. The amount of compound per gland ranged from 2.08 ng for 5 to 0.09 ng for 3. However, analysis of female volatiles by SPME revealed only the presence of compounds, 1, 2, 3, and 5 in a 34:40:4:22 ratio. In electroantennogram assays, compound 1 elicited the highest response, and the C14 acetates evoked higher electrophysiological responses than the corresponding alcohols or C16 isomers. In a wind tunnel, no behavioral difference was observed between formulations based on the gland extracts and female volatiles. In both cases, males responded as when virgin females were used as the attractant source. Compound 1 alone elicited upwind flight by males, but required the presence of compound 5 in a 80:20 to 40:60 ratio for full activity. Ternary mixtures of 1, 5 and the minor components did not improve the performance of the 1+5 blend in a 60:40 ratio. In the field, the mixture 1+5+3 in a 56:37:7 ratio was the most attractive formulation, and is expected to be useful in future pest control strategies.     

Influence of concentration and temperature on the flow behavior of oil-in-water emulsions stabilized by sucrose palmitate

To study the influence that concentration and temperature exert on the viscous behavior of emulsions stabilized by a sucrose ester (SE) of high hydrophilic-lipophilic balance (HLB), flow curves and droplet size distributions were determined. Flow curves of presheared emulsions always exhibited a shear-thinning behavior at intermediate shear rates, a tendency to a limiting viscosity at high shear rates, and a metastable region at low rates. This behavior can be fitted to a Carreau model. Both SE and oil concentrations increase emulsion viscosity as a result of a more structured system with a lower droplet size and polydispersity. An increase in temperature usually leads to a decrease in emulsion viscosity. However, at high oil concentration, coalescence and phase separation take place at low temperature. On the other hand, at high temperature, droplet bursting due to shear forces, leading to an increase in viscosity, may result. Despite the strong structural breakdown caused by steady shear, master flow curves may be obtained by using superposition methods.     

Influence of Complexion Transitions on Microstructure Evolution in Specialty Aluminas

The concept of grain‐boundary complexions has been extended to specialty alumina powders with the goal of deconvoluting the effects of second phase and complexion transitions on microstructure evolution. Two powder compositions with significantly different impurity levels were examined to study the effect of second phase content. The changes in grain size distribution after postsintering annealing for the two compositions were analyzed in order to identify complexion transitions. An analysis technique was developed using probability plots to separate distinct populations of grains of different size regimes. There was evidence of multiple transitions in each material as evidenced by multiple grain size populations. A higher amount of second phase in one powder suppressed the effects of the transitions making the microstructural inhomogeneities less pronounced.     

Preferential attachment of contaminants to filter media in oil

In oil filtration, particles must attach to the filter medium, typically fibres. Attachment is a function of the chemical and physical properties of both the contaminant and the filter medium. Cellulose and synthetic filter media are commonly used in oil filtration. The contaminants include wear metal particles, silica and soot. Because of differences in size and in physical and chemical characteristics, significant differences in contaminant attachment and removal are expected. Experiments were conducted in which filters were challenged with contaminants exhibiting different physical and chemical characteristics. It was found that contaminant shape, roughness and size distribution influence removal. Indirect evidence suggests that chemical interactions also influence removal. The structure of the filter medium mediates these effects.     

Monitoring quality attributes for high-shear wet granulation with audible acoustic emissions

Continuing development of process analytical technology (PAT) tools is needed in the pharmaceutical industry to provide more flexible processing and achieve products of consistent quality. For high-shear wet granulation, audible acoustic emissions (AAEs) have shown potential as a PAT tool for monitoring changes in physical properties related to product quality. This article develops the relationship between AAEs and two critical quality attributes, size and density, and investigates the potential for monitoring product quality online. Condenser microphones were placed inside the air exhaust of a PMA-10 high-shear granulator to collect AAEs for a design of experiment (DOE) where particle size and density were varied by changing the grade of Avicel in the formulation. The results showed increases in particle size and density affect the observed decreases in the AAEs at granulation end-point and during over wetting. In addition, the changes in size and density could be represented by different combinations of 10 Hz frequency groups and the trends in the multivariate scores support online monitoring.     

Targeting Glycolysis in Macrophages Confers Protection Against Pancreatic Ductal Adenocarcinoma

Inflammation in the tumor microenvironment has been shown to promote disease progression in pancreatic ductal adenocarcinoma (PDAC); however, the role of macrophage metabolism in promoting inflammation is unclear. Using an orthotopic mouse model of PDAC, we demonstrate that macrophages from tumor-bearing mice exhibit elevated glycolysis. Macrophage-specific deletion of Glucose Transporter 1 (GLUT1) significantly reduced tumor burden, which was accompanied by increased Natural Killer and CD8+ T cell activity and suppression of the NLRP3-IL1β inflammasome axis. Administration of mice with a GLUT1-specific inhibitor reduced tumor burden, comparable with gemcitabine, the current standard-of-care. In addition, we observe that intra-tumoral macrophages from human PDAC patients exhibit a pronounced glycolytic signature, which reliably predicts poor survival. Our data support a key role for macrophage metabolism in tumor immunity, which could be exploited to improve patient outcomes.     

Effective enhancement of anticorrosive properties of polystyrene by polystyrene–clay nanocomposite materials

A series of polymer–clay nanocomposite (PCN) materials consisting of polystyrene (PS) and layered montmorillonite (MMT) clay was prepared by effectively dispersing the inorganic nanolayers of MMT clay in the organic PS matrix via in situ thermal polymerization. Organic styrene monomers were first intercalated into the interlayer regions of organophilic clay hosts, followed by a typical free radical polymerization with BPO as the initiator. The as‐synthesized PCN materials were characterized by infrared spectroscopy (IR), wide‐angle powder X‐ray diffraction (XRD) and transmission electron microscopy (TEM). PCN coatings with low clay loading (1 wt %) on cold‐rolled steel (CRS) were found to be superior in anticorrosion to those of bulk PS, based on a series of electrochemical measurements of corrosion potential, polarization resistance and corrosion current in a 5 wt % aqueous NaCl electrolyte. The molecular weights of PS extracted from PCN materials and bulk PS were determined by gel permeation chromatography (GPC) with tetrahydrofuran (THF) as the eluent. The effects of material composition on molecular barrier and thermal stability of PS and PCN materials, in the form of both free‐standing films and fine powders, were also studied by molecular permeability analysis, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1970–1976, 2004     

Islet preconditioning via multimodal microfluidic modulation of intermittent hypoxia

Simultaneous stimulation of ex vivo pancreatic islets with dynamic oxygen and glucose is a critical technique for studying how hypoxia alters glucose-stimulated response, especially in transplant environments. Standard techniques using a hypoxic chamber cannot provide both oxygen and glucose modulations, while monitoring stimulus-secretion coupling factors in real-time. Using novel microfluidic device with integrated glucose and oxygen modulations, we quantified hypoxic impairment of islet response by calcium influx, mitochondrial potentials, and insulin secretion. Glucose-induced calcium response magnitude and phase were suppressed by hypoxia, while mitochondrial hyperpolarization and insulin secretion decreased in coordination. More importantly, hypoxic response was improved by preconditioning islets to intermittent hypoxia (IH, 1 min/1 min 5-21% cycling for 1 h), translating to improved insulin secretion. Moreover, blocking mitochondrial K(ATP) channels removed preconditioning benefits of IH, similar to mechanisms in preconditioned cardiomyocytes. Additionally, the multimodal device can be applied to a variety of dynamic oxygen-metabolic studies in other ex vivo tissues.