High resolution slab gel electrophoresis of 8-amino-1,3, 6-pyrenetrisulfonic acid (APTS) tagged oligosaccharides using a DNA sequencer

A novel electrophoretic method for the analysis of oligosaccharides using DNA sequencer technology is illustrated using malto-oligosaccharide distributions obtained following isoamylase digestion of glycogen, wheat starch and potato starch. The debranched starches were derivatized at the reducing and with the charged fluorophore 8-amino-1,3,6-pyrenetrisulfonic acid (APTS). This highly reproducible method provides baseline resolution of oligomers from chain lengths of 3 to more than 80 glucose units, and exhibits high sensitivity with detection thresholds of one femtomole per resolved band. In addition, the reductive amination procedure attaches a single fluorophore per oligosaccharide, allowing calculation of the results on either a mass or a molar basis. The efficacy of the method is illustrated through the determination of the profile of individual oligosaccharides of chain length with a degree of polymerization (DP) < 80, derived from loading less than 15 ng per analysis of glycogen, wheat and potato starches. While the results obtained were superior in resolution and sensitivity to previously reported observations using a range of techniques, they were nonetheless consistent with the overall differences between these polysaccharides. The resolution, sensitivity, reproducibility and high throughput of the method provides substantial advantages over existing methods for the analysis of linear oligosaccharide chain length distributions.     

Social support and coping strategies as mediators of adult adjustment following childhood maltreatment

Structural equation modelling (SEM) was used to examine whether coping efforts and social support mediate the long-term sequelae of child maltreatment. The hypothesized SEM fit the data well and indicated that the association between previous childhood sexual and physical maltreatment and current psychological adjustment appeared to be strongly mediated by social support and coping strategies. In this sample of 302 female and male university students, most of whom reported at least one episode of childhood maltreatment, perceived social support and ways of coping with earlier maltreatment appeared essential to an understanding of the relationship between childhood maltreatment and later adjustment.     

Rapid detection of different RNA respiratory virus species by multiplex RT-PCR: application to clinical specimens

Inconsistent findings from recent mortality studies of workers exposed to magnetic fields have led to calls for more detailed understanding of exposure distributions and metrics in various industries. The authors undertook personal monitoring at an automobile transmission plant to (a) learn if magnetic field exposure differences were present, (b) make assignments for a brain cancer study, and (c) compare two exposure indices. A wide range of average exposures occurred (i.e., 0.016-4.6 microtesla). Within-day variability was also large, and it reached 4 orders of magnitude for some workers. Unexpectedly, demagnetizers were found among the strong sources that contributed to elevated exposures. The authors used conventional summary measures to assign job groups to exposure categories, and they used a new index of exposure irregularity to make alternative assignments. These new assignments appeared to differ from the original ones with respect to work time in each exposure group (i.e., 54% of the work time fell into different exposure categories).     

Role of the brain in interleukin-6 modulation

High levels of interleukin 6 (IL-6) have been found in the brain tissue or cerebrospinal fluid (CSF) in several CNS disorders including Alzheimer's disease, AIDS dementia complex, multiple sclerois, stroke, Parkinson's disease, traumatic brain injuries, brain tumors and CNS infections. In these diseases, IL-6 is also found in blood showing that CNS conditions can elicit a peripheral immune response. A direct secretion of IL-6 from brain to blood has been shown to be a major mechanism by which the brain activates peripheral metabolic, endocrine and immune responses. However, this communication is not straightforward and other regulatory mechanisms are likely to be there. Several lines of evidence obtained in the laboratory have shown that the brain significantly modulates IL-6 production in the periphery. Evidence will be given that: (i) central inflammatory stimuli efficiently induce peripheral IL-6; (ii) central opioids are effective modulators of peripheral IL-6, and (iii) the sympathetic nervous system represents an inhibitory pathway to peripheral IL-6.     

The current state of health care in the former Soviet Union: implications for health care policy and reform

OBJECTIVE: To study planning of movement in Parkinson's disease. METHODS: The spatiotemporal pattern of movement related desynchronisation (MRD) preceding a self paced voluntary wrist flexion was compared between two groups of 10 untreated right and left hemiparkinsonian patients receiving no treatment and 10 control subjects. The MRD was computed in the 9 to 11 Hz frequency band from 11 source derivations covering the frontocentral, central, and parietocentral areas, during two successive left and right experimental conditions. RESULTS: In the two patient groups the desynchronisation appeared over the primary sensorimotor area contralateral to the affected side with a shorter latency (750 ms before movement onset for the right hemiparkinsonian group and 875 ms for the left hemiparkinsonian group) than in the control group (1750 ms), only when the movements were performed with the akinetic hand. For the non-affected hand, the same latency as in the control group was noted (1750 ms). CONCLUSION: The delay of appearance of MRD in Parkinson's disease confirmed that the programming of movement is affected, thus partially explaining akinesia.     

Determination of free malonaldehyde formed in liver microsomes upon CCl4 oxidation

Free malonaldehyde formed in the microsomes prepared from livers of monkey, rat, rabbit, mouse, cow, pig, dog, sheep and horse upon CCl4 oxidation was derivatized by reaction with N-methylhydrazine to form 1-methylpyrazole which was subsequently analyzed by capillary gas chromatography. Among the livers from animals tested, the monkey and rat livers produced the most malonaldehyde upon CCl4 treatment. Horse liver showed the greatest resistance to CCl4 oxidation. The gas chromatography method used in the present study exhibited an accurate and specific measurement of free malonaldehyde that might provide an understanding of the biochemical process of in vitro lipid peroxidation.     

Site-directed mutations in the third domain of Bacillus thuringiensis delta-endotoxin CryIAa affect its ability to increase the permeability of Bombyx mori midgut brush border membrane vesicles

A series of mutant Bacillus thuringiensis CryIAa delta-endotoxin proteins was prepared by replacing the first, second, and last arginine residues of the conserved third-domain sequence, R-521 YRVRIR-527, with other amino acids. The stable mutant proteins were bioassayed against Bombyx mori larvae and found to all be approximately half as active as wild-type CryIAa. The toxins were also tested by means of a light-scattering assay for their ability to increase permeability of larval B. mori midgut brush border membrane vesicles. Three of the mutant toxins were as active as the wild-type toxin in the vesicle permeability assay.