Alternative Pathways of Glucose Utilization in Brain; Changes in the Pattern of Glucose Utilization in Brain Resulting from Treatment of Rats with 6-Aminonicotinamide

The effect of 6-aminonicotinamide (6AN) treatment on the activities of alternative pathways of glucose metabolism in 20-day-old rat brain was evaluated by measurements of yields of 14CO2 from glucose labeled with 14C on carbons 1, 2, 3 + 4, or 6 and uniformly labeled glucose, and from the incorporation of 14C from specifically labeled glucose into lipids by brain slices from cerebral hemispheres and cerebellum. At the highest dose of 6AN used (35 mg/kg body weight) there was a significant decrease in the 14CO2 yields via the pentose phosphate pathway, the glycolytic route, tricarboxylic acid (TCA) cycle, and via the glutamate-gamma-aminobutyric acid pathway. Giving a graded series of doses (20-35 mg 6AN/kg body weight) revealed a hierarchy of responses in which the pentose phosphate pathway, lactate, glyceride-glycerol, and fatty acid formation were most sensitive, followed, in sequence, by the pyruvate dehydrogenase reaction, the glutamate-gamma-aminobutyrate route and, finally, the TCA cycle. The nature of the blocks in the various pathways was examined by the use of metabolite profiles.     

The multi-locus H-2D w16 region has an organization distinct from the D d region

Genomic DNA blot analyses using probes derived from the BALB/c 3 flanking region of the L ^d gene (L ^d 3 fl-C) and from near the BALB/c D3 ^d gene (50.2A) indicate that the B10.GAA37 mouse strain has a multi-locus D (D ^w16) region distinct from the five-gene organization observed in the D ^d and D ^q regions. To isolate the D ^w16 region class I genes, a genomic B10. GAA37-EMBL3 library was generated and screened with probes that preferentially hybridize to K and D region class I genes. Hybridization analyses of the isolated clones with L ^d derived oligonucleotide probes suggested that one of the clones contained the L ^w16 gene, whereas several other clones contained the L ^w16 gene. The sequence of the D ^w16 gene is most similar to that of the D ^p gene, particularly in the 3 half. Furthermore, the L ^w16 gene is quite similar in the 5 half and virtually identical in the 3 half to the L ^d gene, indicating that L ^w16, but not D ^w16, is a member of the L ^d gene family. Collectively, these data suggest that, through a D region recombination event, the novel D ^w16 region may have been assembled from primordial counterparts of the D ^p and L ^d genes.The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession number M60774-M60776, and M62759.     

The role of stress and level of burnout in job performance among nurses

Nurses' empathy for and connection with patients demonstrates core professional values which are essential but, consequently, attract certain factors capable of inducing stress. Studies of the roles and responsibilities associated with nursing have implicated multiple and conflicting demands which might not be without some resultant effects. However, little research has been conducted on these work characteristics in developing economies to determine how these might impact the nurse employees' performance. There is need for evidence-based empirical findings to facilitate improvement in healthcare services. This study examined stress and level of burnout among Nigerian nurses (n = 2245) who were selected using stratified random sampling. The participants were measured using an 'abridged measures booklet' adopted from the Maslach Burnout Inventory-General Survey (MBI-GS), Job Autonomy Questionnaire (JAQ), Questionnaire on Organisational Stress-Doetinchem (VOS-D) and Job Diagnostic Survey (JDS). The roles of work-home interference (WHI) and home-work interference (HWI), with respect to work characteristics and burnout (paying special attention to gender), were examined. Analyses using t-tests and linear regression showed no gender differences in burnout levels among Nigerian nurses, who experience medium to high levels of emotional exhaustion, medium levels of depersonalisation and high levels of personal accomplishment. WHI and HWI were found to mediate the relationship between work characteristics and burnout. The meditational relationship differs between genders. This study calls for further research into gender and burnout among the caring professions, especially in under-developed and developing economies of the world.     

Alternative Pathways of Glucose Utilization in Brain: Changes in the Pattern of Glucose Utilization and of the Response of the Pentose Phosphate Pathway to 5-Hydroxytryptamine During Aging

Abstract: The oxidation of differentially labelled glucose, pyruvate and glutamate in brain slices from rats aged 20 days to 26 months has been studied and the partition of the glucose used into the glycolytic-tricarboxylic acid cycle pathway, the pentose phosphate pathway and the glutamate-GABA shunt has been calculated. Over the time range 4 to 26 months, there is an approximately 20% decrease in the production of CO₂ via the glycolytic-tricarboxylic acid cycle route, as there is in the rate of glucose phosphorylation. The glutamate-GABA pathway falls by about 50% over this same time span. The broad activity of the pentose phosphate pathway falls rapidly and cannot be detected in the brains of rats aged 18 months or more, whereas the fully stimulated pathway, i.e. in the presence of the artificial electron acceptor phen-azine methosulphate, declines only marginally over this period, falling sharply only after 23 months. The pentose phosphate pathway is stimulated by the presence of 5-hy-droxytryptamine and this stimulation appears to increase with age.