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Identification of the Neurobiological Basis of Hemodynamic Responses Correlated with Cognitive Stroop Task Performance After an Acute Bout of Aerobic Exercise

Description: Cardiovascular activities may increase the brain blood flow improving neuronal activities leading to improved cognition. Consequently, the effects of an acute bout of moderate intensity aerobic exercise on brain hemodynamics and its correlation with cognitive color-word Stroop task performance were tested. The Stroop tasks were congruent (color matches word) and incongruent (color does not match word). Prefrontal (PFC) and motor cortex (MC) blood flow was recorded by fNIRS (functional near-infrared spectroscopy) while the subject was performing the Stroop tasks before and after the 30 minutes of exercise or equivalent time of rest controls (checking for practice effects). Ninety human subjects of age 24± 6, 20 ADHD (attention-deficit hyper-activity disorder), 27 High-BMI (>25), 29 males were recruited. Reaction time ‘RT' decreased (p<0.05) after exercise for both the congruent (12%) and incongruent (10%) Stroop tasks, compared to 8% with practice alone. Accuracy did not change after practice or exercise. HR changes after exercise correlated (p<0.05) with better accuracy and faster RT for the incongruent Stroop task. In general, a metabolic lag occurred in the neuronal deoxy- hemoglobin (Hb) signals behind the systemic oxy-Hb signals. PFC showed the highest effect sizes of Stroop task-responsive systemic hemodynamic changes compared to baseline irrespective of rest or exercise. Yet, PFC showed most significant (p<0.001) neuronal hemodynamic changes between the before and after exercise sessions, and these changes were opposite for right and left PFC, and opposite for congruent and incongruent Stroop tasks. Correlating the RT and mistakes with hemodynamics for both the Stroop tasks revealed that, after exercise, neuronal hemodynamic changes occurred at both PFC and MC associated with faster RT (p<0.05), and systemic hemodynamic responses occurred at PFC correlated (p<0.05) with mistakes. Overall, it was concluded that exercise changed the neuronal hemodynamic changes affecting speed; however, neuronal metabolic changes did not occur sufficiently to help ...
Date: May 2018
Creator: Pal, Amrita
Partner: UNT Libraries

Microbial actinomycete population studies in lacustrine substrates

Description: The discovery of the production of antibiotic materials by certain members of the Actinomycetales has stimulated the study of these organisms over the last two decades, raising them from a position of little significance to one of noticeable importance. These studies include investigations concerning the physiology and biochemistry of the actinomycetes.
Date: August 1968
Creator: Brothers, James Walker
Partner: UNT Libraries

Physical characterization and restriction mapping of the SAL plasmid from Pseudomonas putida

Description: Physical and restriction mapping of the salicylate catabolic plasmid SAL from Pseudomonas putida strain PpG 2119 was carried out by standard multiple restriction analysis and by cross hybridization studies using radioactively labeled restriction fragment probes. The total numbers of fragments produced, their respective sizes, the arrangement of the restriction fragments on the plasmid and the map locations of the enzyme recognition sites for Hpal, Xhol, Dral and Smal are given.
Date: December 1987
Creator: Asghari, Abdolkarim
Partner: UNT Libraries

Fumarase from Ascaris suum: partial purification and characterization

Description: One molecular form of fumarase from Ascaris suum was demonstrated by cellulose acetate electroporesis and isoelectric focusing. The enzyme was partially purified by ammonium sulfate fractionation and ion-exchange chromatography to a specific activity of 49 units per mg protein. Enzymatic assay of the partially purified by ammonium sulfate fractionation amd ion-exchange chromatography to a specific activity of 49 units per mg protein. Enzymatic assay of the partially purified preparation showed glyceraldehyde-3-phosphate dehydrongenase to be the major preparative contaminant.
Date: May 1976
Creator: Powley, David G.
Partner: UNT Libraries

Purification and characterization of Ascaris suum hexokinase

Description: A procedure for purifying hexokinase from Ascaris muscle has been developed. The physical and catalytic properties of the enzyme are comparable to mammalian hexokinases. The enzyme is a monomer with a molecular weight of 100,000 as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis and gel filtration.
Date: August 1975
Creator: Supowit, Scott C.
Partner: UNT Libraries

Effects of lysolecithin on macrophages

Description: The effect of lysolecithin on the macrophage was studied using five macrophage function assays. The results of indicate that lyso lecithin is a macrophage activating agent which causes enhanced cell spreading, increased phagocytosis of sheep erythrocytes, heightened membrane activity in the presence of damaged autologous red blood cells, chemotaxis, and vigorous phagocytosis and intracellular killing of Staphylococcus albus.
Date: May 1988
Creator: Swee, Mei Hua
Partner: UNT Libraries