Effect of Pasteurization and Retort Processing on Spectral Characteristics,Morphological, Thermal,Physico‐Mechanical,Barrier and Optical Properties of Nylon‐Based Food Packaging Materials

The effect of pasteurization and retort processing on spectral, morphological, thermal, physico‐mechanical, barrier and optical properties of three different packaging materials viz., PP/N6/PP, PET/N6/cPP and SiO_x‐PET/N6/cPP were studied. These packaging materials were packed with distilled water, which acted as a food simulant. Subsequently, these pouches were subjected to different thermal processing conditions such as pasteurization and retort processing. Both the processing techniques found to have retained the mechanical properties of all packaging materials. Water vapour transmission rate (WVTR) and oxygen transmission rate (OTR) of nylon‐based combinations were increased after processing. Gloss found to decrease invariably irrespective of the material and increases with the severity of the treatment. XRD diffractogram shows changes in crystal structure as a result of thermal processing, and SEM analysis shows the crystal fragmentation. Absorption of water by the amide group of nylon 6 was observed, which could be a reason for the increase in OTR and WVTR. Copyright © 2014 John Wiley & Sons, Ltd.     

In vivo microdialysis and gas chromatography/mass spectrometry for studies on release of N-acetylaspartlyglutamate and N-acetylaspartate in rat brain hypothalamus

Microdialysis and gas chromatography/mass spectrometry was used for the measurement of extracellular N-acetylaspartate (NAA) and N-acetylaspartylglutamate (NAAG) in rat hypothalamus. The sensitivity of the method for each of these compounds was approximately 5 pmol/30 microliters of dialysate. Baseline NAA concentrations in dialysate were estimated to be approximately 25 pmol/36 microliters, while that for NAAG was at or below the detection limit of 5 pmol/ 36 microliters. In vivo and in vitro calibrations of microdialysis probes showed that the recovery for NAA was approximately 10 percent. For NAAG, the in vitro recovery was 6.3%, and in vivo recovery, 11%. Depolarization stimulation using 100 mM KCl in the microdialysis perfusate was employed to measure extracellular NAA and NAAG concentrations. Extracellular NAA was elevated to approximately 70 pmol/36 microliters dialysate following depolarization. No significant elevation of NAAG was observed. By infusing known amounts of stable isotopically labeled NAAG-d3 via the microdialysis probe and measuring the isotopically labeled catabolic product, NAA-d3, in collected microdialysate, we were able to confirm the existence of one or more hydrolytic enzymes active towards NAAG in the hypothalamus. This finding suggest the possible involvement of active metabolic processes in the relationship between NAAG and NAA releases.     

Performance of children with ADHD on the Rey-Osterrieth complex figure: a pilot neuropsychological study

This study evaluates the performance of boys with Attention Deficit Hyperactivity Disorder (ADHD) on the Rey-Osterrieth Complex Figure (ROCF) taking into consideration familiality and comorbid psychiatric and learning disorders (LD). Sixty-five children with ADHD performed at developmentally lower levels of Copy Organization and Recall Style than did 45 controls. ADHD children with LD scored significantly lower on Copy Organization than did ADHD children without LD, whereas psychiatric comorbidity and familiality had no effect. These results suggest that a developmental analysis of the ROCF identifies organizational difficulties associated with ADHD and that these impairments cannot simply be attributed to comorbidities associated with ADHD.     

Modulation of the voltage-gated sodium current in rat striatal neurons by DARPP-32, an inhibitor of protein phosphatase

DARPP-32 is a cyclic adenosine monophosphate-regulated inhibitor of protein phosphatase 1, highly enriched in striatonigral neurons. Stimulation of dopamine D1 receptors increases phosphorylation of DARPP-32, whereas glutamate acting on N-methyl-D-aspartate receptors induces its dephosphorylation. Yet, to date, there is little direct evidence for the function of DARPP-32 in striatal neurons. Using a whole cell patch-clamp technique, we have studied the role of DARPP-32 in the regulation of voltage-gated sodium channels in rat striatal neurons maintained in primary culture. Injection of phospho-DARPP-32, but not of the unphosphorylated form, reduced the sodium current amplitude. This effect was similar to those induced by okadaic acid, with which there was no additivity and by tautomycin. Our results indicate that, in striatal neurons, sodium channels are under dynamic control by phosphorylation/dephosphorylation, and that phospho-DARPP-32 reduces sodium current by stabilizing a phosphorylated state of the channel or an associated regulatory protein. We propose that the DARPP-32-mediated modulation of sodium channels, via inhibition of phosphatase 1, contributes to the regulation of these channels by D1 receptors and other neurotransmitters which influence the state of phosphorylation of DARPP-32.