Fucoidan Hydrogels Significantly Alleviate Oxidative Stress and Enhance the Endocrine Function of Encapsulated Beta Cells

Microencapsulating pancreatic islets in immunoprotective alginate hydrogels is a promising strategy for treatment of type 1 diabetes. However, this strategy is limited by inflammation and hypoxia mediated oxidative stress, due to encapsulation and the hydrogel itself, leading to impaired insulin secretion and limited short and long term cell survival. Herein, the antioxidant effect of fucoidan, an algae derived polysaccharide, on beta cells, and its positive effects on encapsulated beta cell viability and function is presented. Fucoidan from Fucus vesiculosus (FF) exhibits a high total antioxidant capacity, and free radical scavenging activity, and is able to significantly alleviate intracellular oxidative stress in rat insolinoma beta cells (INS1E). In addition, FF significantly increases insulin secretion in a dose- and time-dependent manner. When FF is incorporated in ultrapure alginate used for microencapsulation of primary rat islets, both viability and glucose responsiveness of rat islets in these socalled Fucogel microcapsules (Fucocaps) are found to be significantly higher compared to islets encapsulated in alginate alone. Similar results are obtained with INS1E pseudoislets and neonatal pig islets. Fucocaps can provide a redox-modulatory niche and an immune barrier for islets and beta cells in the same time leading to significantly improved survival and endocrine function by mitigating oxidative stress.     

Photochemical Generation of Light Responsive Surfaces

The preparation of patterned photoswitchable surfaces by employing the nitrile imine‐mediated tetrazole ene cycloaddition (NITEC) photoinduced reaction in the presence of dipolarophiles based on photoresponsive azobenzene moieties is reported. The dipolarophile used is a maleimide carrying either an azobenzene unit or a first generation dendron containing two azobenzene units. X‐ray photoelectron spectroscopy (XPS) is employed to analyze the functionalized silicon wafers, while time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) evidences the spatial control of the functionalization of the surface achieved by using a micropatterned shadow mask. Water contact angle measurements and optical inspection observing the behavior of a water droplet demonstrate the photoinduced change on wettability of the structured functionalized surfaces due to the reversible trans‐to‐cis isomerization of the azobenzene moities.     

Evaluation of alternatives to cautery disbudding of dairy goat kids using physiological measures of immediate and longer-term pain

We evaluated alternatives to cautery disbudding of goat kids using physiological measures of immediate and longer-term pain. Fifty Saanen doe kids were randomly assigned to 1 of 5 treatments (n = 10/treatment): (1) cautery disbudding (CAUT), (2) caustic paste disbudding (CASP), (3) liquid nitrogen disbudding (CRYO), (4) clove oil injected into the horn bud (CLOV), or (5) sham disbudding (SHAM). Serum cortisol and haptoglobin concentrations were measured from blood samples collected immediately before treatment (baseline) and at 15, 30, 60, and 120 min and then again at 6 and 24 h post-treatment. An infrared thermography camera was used to take images of the horn buds 24 h pre- and 24, 48, and 72 h post-treatment to measure skin temperature. Body weight was measured daily for 1 wk to assess weight change post-treatment. Images of the horn buds were taken at d 1, 2, and 7 and at 6 wk post-treatment to assess tissue damage and wound healing. Mean cortisol concentrations were elevated in CASP kids 1 h post-treatment relative to CAUT kids. Cortisol concentrations of CRYO kids were higher than those of CAUT kids 30 min post-treatment; concentrations for CLOV kids were similar to CAUT kids post-treatment. Mean haptoglobin concentrations were similar across treatments over time; however, CLOV kids had higher concentrations at 24 h post-treatment than all other treatments. Skin temperatures of CASP and CLOV kids were elevated relative to CAUT kids at all time points post-treatment, and all disbudded kids had skin temperatures above those of SHAM kids at 72 h post-treatment. Treatment did not influence weight gain. The CAUT kids had large, open wounds exposing bone; small scabs were still evident 6 wk post-treatment. The CASP kids had red and open, raw wounds that generated large eschars, apparent for up to 6 wk. The CRYO kids had closed, dry wounds initially, but over time lesions appeared that caused open wounds; small scabs were present 6 wk post-treatment. The CLOV kids had closed, dry wounds with blackened skin; healed skin and minimal scabs were present 6 wk post-treatment. Caustic paste and cryosurgical disbudding appeared to cause more pain compared with cautery disbudding; thus, these methods may not provide good alternatives to cautery disbudding. Clove oil appeared to cause a similar pain response as cautery disbudding and smaller wounds with earlier tissue repair; this method shows promise as an alternative to cautery disbudding.     

Liquid Chromatography-Tandem Mass Spectrometry Determination and Depletion Profile of Chlortetracycline,Doxycycline, and Oxytetracycline in Broiler Chicken Muscle After Oral Administration

A simple and fast method based on liquid chromatography–electrospray ionization-tandem mass spectrometry (LC–ESI-MS/MS) was developed and validated for determination of tetracyclines in broiler chicken muscle. Sample preparation was performed using extraction with acetonitrile, followed by low-temperature purification (at ??20 °C) and further concentration. The chromatographic analysis was carried out using a Zorbax SB-C18 column with gradient elution using water and methanol both acidified with 0.025 M of formic acid. Mass spectrometry with electrospray ionization was operated in positive polarity using selected reaction monitoring (SRM) analysis mode, achieving the requirements of four identification points for each compound. Demeclocycline was used as internal standard. The method validation was done according to the criteria of Commission Decision 2002/657/EC. Parameters such as recovery, matrix effects, selectivity/specificity, linearity, precision (intra- and inter-day precision), accuracy, limits of detection (LOD) and quantification (LOQ), decision limit (CCα), detection capability (CCβ), and robustness were determined. Intra-day precision values were within the range 2.2–5.8% and inter-day precision was less than 10% for all analytes. Accuracy ranged from 98.2 to 103.2%. The method was successfully applied for depletion studies of chlortetracycline, doxycycline, and oxytetracycline in broiler chicken tissues after multiple oral administrations. After the depletion studies, the present study support more prudent use of CTC, DOX, and OTC for treatment of chickens and suggest a dose of 60 mg kg^?1 body weight for CTC and OTC and 20 mg kg^?1 body weight for DOX, orally administrated for five consecutive days.     

Biochemical composition of two red seaweed species grown on the Brazilian coast

BACKGROUND: Algae species have been used as an important source of food because they are highly nutritive considering their vitamin, protein, mineral, fiber, essential fatty acid and carbohydrate contents. However, a large number of seaweeds have been poorly studied, especially Brazilian species. Two red macroalgae species from the Brazilian coast (Plocamium brasiliense and Ochtodes secundiramea) were assessed with respect to their total lipid, fatty acid, total nitrogen, protein, amino acid and total carbohydrate contents. RESULTS: The total lipid contents (dry weight) were 36.3 and 35.4 g kg^?1; fatty acid contents were 9.3 and 12.1 g kg^?1; total nitrogen contents were 37.4 and 24.9 g kg^?1; protein contents were 157.2 and 101.0 g kg^?1; amino acid contents were 127.5 and 91.4 g kg^?1; and total carbohydrate contents were 520.3 and 450.7 g kg^?1 for P. brasiliense and O. secundiramea, respectively. CONCLUSION: Considering these compositions, both algae species were determined to have sources of protein, essential amino acids and carbohydrates similar to the edible seaweeds Laminaria japonica and Palmaria palmata. Copyright © 2011 Society of Chemical Industry     

Equivalence salting and temporal dominance of sensations analysis for different sodium chloride substitutes in cream cheese

The purpose of the study was to determine the potency and equivalence of salt substitutes (potassium chloride, magnesium chloride, monosodium glutamate, potassium lactate, calcium lactate and potassium phosphate monobasic) in cream cheese and to evaluate sensory flavour profiles. The methods used were magnitude estimation and temporal dominance of sensations (TDS). Equivalent salting of cream cheese containing 1% sodium chloride was obtained using: 1.2% potassium chloride, 2.56% monosodium glutamate, 2.5% magnesium chloride and 2.98% potassium phosphate. The TDS revealed that, other than salty taste, the most significant flavours produced were sour and bitter. The potencies of salt substitutes are much lower than that of sodium chloride.     

Information-theoretic feature selection for functional data classification

The classification of functional or high-dimensional data requires to select a reduced subset of features among the initial set, both to help fighting the curse of dimensionality and to help interpreting the problem and the model. The mutual information criterion may be used in that context, but it suffers from the difficulty of its estimation through a finite set of samples. Efficient estimators are not designed specifically to be applied in a classification context, and thus suffer from further drawbacks and difficulties. This paper presents an estimator of mutual information that is specifically designed for classification tasks, including multi-class ones. It is combined to a recently published stopping criterion in a traditional forward feature selection procedure. Experiments on both traditional benchmarks and on an industrial functional classification problem show the added value of this estimator.