Non-Lethal Endotoxin Injection: A Rat Model of Hypercoagulability

Systemic inflammation co-activates coagulation, which unchecked culminates in a lethal syndrome of multi-organ microvascular thrombosis known as disseminated intravascular coagulation (DIC). We studied an endotoxin-induced inflammatory state in rats to identify biomarkers of hemostatic imbalance favoring hypercoagulability. Intraperitoneal injection of LPS at 15 mg/kg body weight resulted in peripheral leukopenia and widespread neutrophilic sequestration characteristic of an acute systemic inflammatory response. Early indicators of hemostatic pathway activation developed within 4 hours, including increased circulating concentrations of procoagulant extracellular vesicles (EVs), EVs expressing endothelial cell and platelet membrane markers, and high concentration of soluble intercellular adhesion molecule-1 (sICAM-1), plasminogen activator inhibitor-1 (PAI-1), and D-dimers. Inflammation persisted throughout the 48-hour observation period; however, increases were found in a subset of serum microRNA (miRNA) that coincided with gradual resolution of hemostatic protein abnormalities and reduction in EV counts. Dose-adjusted LPS treatment in rats provides a time-course model to develop biomarker profiles reflecting procoagulant imbalance and rebalance under inflammatory conditions.

How dietary cottonseed hull affects the performance of young bulls finished in a high-concentrate system

This study aimed to evaluate the effects of diets composed of cottonseed hull on feed intake, in vitro digestibility, animal performance, carcass characteristics and ingestive behaviour of young bulls (1/2 Simmental × 1/2 Nellore) fed in a high-concentrate system. Thirty crossbred young bulls (319 ± 12.5 kg of bodyweight, and 11 ± 0.8 months old) were assigned to a complete randomised experimental design of three diets (CH21: cottonseed hull 210 g/kg on a DM, basis; CH27: cottonseed hull 270 g/kg on a DM basis; CH33: cottonseed hull 330 g/kg on a DM basis) with 10 animals per group. The animals were kept in a feedlot for 162 days. The cottonseed hull diets had effects on DM intake and neutral detergent fibre intake. The CH21 diet reduced the DM and detergent fibre intakes (kg/day and kg/100 kg bodyweight) and increased the in vitro digestibility of DM. However, the in vitro digestibility of neutral detergent fibre was greater with the CH27 diet. The cottonseed hull diets did not have effects on animal performance or the carcass characteristics of young bulls. However, the CH33 diet reduced the feed efficiency of the animals. A cottonseed hull level up to 270 g/kg of dietary DM may be utilised as a non-forage fibre in high-concentrate diets for young bulls in feedlots.

Factors influencing aversive learning in the oriental fruit fly, Bactrocera dorsalis

Parameters such as the intensity of conditioned and unconditioned stimuli, the inter-trial interval, and starvation time can influence learning. In this study, the parameters that govern aversive learning in the oriental fruit fly, Bactrocera dorsalis, a serious pest of fruits and vegetables, were examined. Male flies were trained to associate the attractive odorant methyl eugenol, a male lure, with a food punishment, sodium chloride solution, and the conditioned suppression of the proboscis-extension response was investigated. We found that high methyl eugenol concentrations support a stronger association. With increasing concentrations of sodium chloride solution, a steady decrease of proboscis-extension response during six training trials was observed. A high level of learning was achieved with an inter-trial interval of 1-10 min. However, extending the inter-trial interval to 15 min led to reduced learning. No effect of physiological status (starvation time) on learning performance was detected, nor was any non-associative learning effect induced by the repeat presentation of odor or punishment alone. The memory formed after six training trials could be retained for at least 3 h. Our results indicate that aversive learning by oriental fruit flies can be affected by odor, punishment concentration and inter-trial interval.

Microstructural, mechanical, and histological evaluation of modified alginate-based scaffolds

Scaffolds are three-dimensional structures used for tissue regeneration being the base in tissue engineering. These scaffolds are obtained from natural and/or synthetic polymers and they should satisfy some specific requirements such as biocompatibility, suitable mechanical, and microstructural properties to favor cellular adhesion and neovascularization. This work shows a preclinic study about the production of low and medium molecular weight alginate through the use of calcium salts (calcium glutamate). The results showed prove that better structures, distribution, and pore sizes as well as better mechanical properties correspond to medium molecular weight alginate and higher calcium salts concentration. This type of scaffold, after muscular cells cultivation, has been proved as an excellent material for muscle growth. The histopathological analysis shows a low inflammatory response, without a foreign body reaction, suitable neovascularization and good fibroblasts incorporation. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 3107-3114, 2016.

Sexual communication in day-flying Lepidoptera with special reference to castniids or 'butterfly-moths'

Butterflies and moths are subject to different evolutionary pressures that affect several aspects of their behaviour and physiology, particularly sexual communication. Butterflies are day-flying insects (excluding hedylids) whose partner-finding strategy is mainly based on visual cues and female butterflies having apparently lost the typical sex pheromone glands. Moths, in contrast, are mostly night-flyers and use female-released long-range pheromones for partner-finding. However, some moth families are exclusively day-flyers, and therefore subject to evolutionary pressures similar to those endured by butterflies. Among them, the Castniidae, also called 'butterfly-moths' or 'sun-moths', behave like butterflies and, thus, castniid females appear to have also lost their pheromone glands, an unparallel attribute in the world of moths. In this paper, we review the sexual communication strategy in day-flying Lepidoptera, mainly butterflies (superfamily Papilionoidea), Zygaenidae and Castniidae moths, and compare their mating behaviour with that of moth families of nocturnal habits, paying particular attention to the recently discovered butterfly-like partner-finding strategy of castniids and the fascinating facts and debates that led to its discovery.

Influence of collagen concentration and glutaraldehyde on collagen-based scaffold properties

Several studies have shown the influence of the physical properties of scaffolds on their mechanical properties. An initial characterization of a type of collagen protein was carried out by studying its composition andits solubility at different pH values and infrared spectroscopy. Subsequently, porosity and scaffold pore size were studied, assessing how varying the composition of the initial solution (increasing the protein concentration or adding glutaraldehyde) changed the properties of the final scaffolds obtained. Lastly, rheological measurements were performed to evaluate the mechanical strength of the scaffolds. The initial characterization revealed that the type I collagen protein used is considerably denatured. In addition, increasing the protein content in the scaffold decreases the porosity, related to an increase in the elastic modulus producing an enhancement of its mechanical strength, while adding glutaraldehyde to the scaffold increases its mechanical strength without lowering its pore size or porosity. The results obtained are useful in that they demonstrate that it is possible to design a scaffold with specific properties, by just controlling the collagen concentration or adding glutaraldehyde to the initial solution. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1462-1468, 2016.

Effect of the type of dietary fat when added as an energy source on animal performance, carcass characteristics and meat quality of intensively reared Friesian steers

The effects of different fats in the diet were evaluated on the basis of animal performance, carcass and meat-quality traits. Four groups of eight Friesian steers were intensively finished with concentrate and cereal straw given ad libitum. Four different types of fats were included at a 4% level in the diet, namely, palm oil, sunflower oil, tallow and hydrogenated fat. The feeding trial lasted for 84 days. There were no differences on animal performance or carcass characteristics, except for animals from the hydrogenated-fat diet, which had the greatest percentage of muscle and moisture, and the lowest percentage of fat in a 6th rib dissection. Meat colour, texture, lipid oxidation and consumer acceptability did not differ among the diets. Nevertheless, the effects of ageing or display time were more important than those of the source of fat. Intramuscular fatty acid profile was hardly influenced by the fat source. In conclusion, the type of fat added at the final stage of the rearing process, at a 4% of inclusion level, did not produce noticeable variations on productive parameters or product quality. This would allow to formulate rations for cattle, using the most profitable source of fat (added at low levels), without having variability on the product quality.

High sensitivity flow cytometry of membrane vesicles

Extracellular vesicles (EVs) are attracting attention as vehicles for inter-cellular signaling that may have value as diagnostic or therapeutic targets. EVs are released by many cell types and by different mechanisms, resulting in phenotypic heterogeneity that makes them a challenge to study. Flow cytometry is a popular tool for characterizing heterogeneous mixtures of particles such as cell types within blood, but the small size of EVs makes them difficult to measure using conventional flow cytometry. To address this limitation, a high sensitivity flow cytometer was constructed and EV measurement approaches that allowed them to enumerate and estimate the size of individual EVs, as well as measure the presence of surface markers to identify phenotypic subsets of EVs. Several fluorescent membrane probes were evaluated and it was found that the voltage sensing dye di-8-ANEPPS could produce vesicle fluorescence in proportion to vesicle surface area, allowing for accurate measurements of EV number and size. Fluorescence-labeled annexin V and anti-CD61 antibody was used to measure the abundance of these surface markers on EVs in rat plasma. It was shown that treatment of platelet rich plasma with calcium ionophore resulted in an increase in the fraction of annexin V and CD61-positive EVs. Vesicle flow cytometry using fluorescence-based detection of EVs has the potential to realize the potential of cell-derived membrane vesicles as functional biomarkers for a variety of applications.

Estudio comparativo de la calidad de la canal y la carne de lechales de raza Churra Tensina y dos tipos ovinos comerciales amparados bajo marcas de calidad

Se estudió la calidad de la canal y la carne de lechales ovinos comerciales de raza Churra Tensina (n= 26) según la época de cría y sacrificio (primavera vs. otoño). Estos corderos se compararon con otros tipos comerciales amparados bajo marcas de calidad reconocidas en el mercado con denominación de Indicación Geográfica Protegida (IGP): Lechazo de Castilla-León (n= 13) y Ternasco de Aragón (n= 13). Todos los corderos fueron criados, seleccionados y sacrificados en condiciones comerciales. Tras el sacrificio, se valoró la calidad de la canal y de la carne en el músculo Longissimus thoracis y lumborum (LTL). Los lechales de Churra Tensina presentaron diferencias según la época de producción, fundamentalmente en las variables relacionadas con la composición tisular de la canal, presentando, los lechales de primavera, un mayor porcentaje de músculo y hueso, y menor de grasa que los de otoño (p≤0,001), así como una mayor proporción de los ácidos grasos C 12:0, CLA, C 20:2 n-3 o C 22:0 (p≤0,001) en la grasa intramuscular. Estas diferencias de composición no se reflejaron en el análisis sensorial, ya sea mediante panel entrenado o consumidores. La carne de los lechales de la raza Churra Tensina presentó una terneza superior (p≤0,001) a la de los productos IGP con los que se comparó, tanto instrumentalmente como sensorialmente (panel entrenado) y una mayor aceptabilidad tanto general, como del sabor y de la terneza (consumidores) (p≤0,001). Los resultados obtenidos reflejarían el potencial de dicha raza para la producción de lechales de calidad, en ambas estaciones del año.

Biosynthetic infochemical communication

There is an ever-increasing demand for data to be embedded in our environment at ever-decreasing temporal and spatial scales. Whilst current communication and storage technologies generally exploit the electromagnetic properties of media, chemistry offers us a new alternative for nanoscale signaling using molecules as messengers with high information content. Biological systems effectively overcome the challenges of chemical communication using highly specific biosynthetic pathways for signal generation together with specialized protein receptors and nervous systems. Here we consider a new approach for information transmission based upon nature's quintessential example of infochemical communication, the moth pheromone system. To approach the sensitivity, specificity and versatility of infochemical communication seen in nature, we describe an array of biologically-inspired technologies for the production, transmission, detection, and processing of molecular signals. We show how it is possible to implement each step of the moth pheromone pathway for biosynthesis, transmission, receptor protein binding/transduction, and antennal lobe processing of monomolecular and multimolecular signals. For each implemented step, we discuss the value, current limitations, and challenges for the future development and integration of infochemical communication technologies. Together, these building blocks provide a starting point for future technologies that can utilize programmable emission and detection of multimolecular information for a new and robust means of communicating chemical information.

Genetic characterization of Vibrio vulnificus strains isolated from oyster samples in Mexico

Vibrio vulnificus strains were isolated from oysters that were collected at the main seafood market in Mexico City. Strains were characterized with regard to vvhA, vcg genotype, PFGE, multilocus sequence typing (MLST), and rtxA1. Analyses included a comparison with rtxA1 reference sequences. Environmental (vcgE) and clinical (vcgC) genotypes were isolated at nearly equal percentages. PFGE had high heterogeneity, but the strains clustered by vcgE or vcgC genotype. Select housekeeping genes for MLST and primers that were designed for rtxA1 domains divided the strains into two clusters according to the E or C genotype. Reference rtxA1 sequences and those from this study were also clustered according to genotype. These results confirm that this genetic dimorphism is not limited to vcg genotyping, as other studies have reported. Some environmental C genotype strains had high similarity to reference strains, which have been reported to be virulent, indicating a potential risk for oyster consumers in Mexico City.

Identification and characterization of a fatty acyl reductase from a Spodoptera littoralis female gland involved in pheromone biosynthesis

Fatty acyl-CoA reductases (FARs), the enzymes that catalyse reduction of a fatty acyl-CoA to the corresponding alcohol in insect pheromone biosynthesis, are postulated to play an important role in determining the proportion of each component in the pheromone blend. For the first time, we have isolated and characterized from the Egyptian cotton leaf worm Spodoptera littoralis (Lepidoptera: Noctuidae) a FAR cDNA (Slit-FAR1), which appeared to be expressed only in the pheromone gland and was undetectable in other female tissues, such as fat body, ovaries, wings, legs or thorax. The encoded protein has been successfully expressed in a recombinant system, and the recombinant enzyme is able to produce the intermediate fatty acid alcohols of the pheromone biosynthesis of S. littoralis from the corresponding acyl-CoA precursors. The kinetic variables Km and Vmax, which have been calculated for each acyl-CoA pheromone precursor, suggest that in S. littoralis pheromone biosynthesis other biosynthetic enzymes (e.g. desaturases, acetyl transferase) should also contribute to the final ratio of components of the pheromone blend. In a phylogenetic analysis, Slit-FAR1 appeared grouped in a cluster of other FARs involved in the pheromone biosynthesis of other insects, with little or non-specificity for the natural pheromone precursors.