No description available.

No description available.

No description available.

The wound healing response within corneal epithelium cells is controlled by the purinergic P2X7 receptor, purinergic P2Y2 receptor, and Pannexin1 transmembrane proteins. The response is initiated by the release of ATP into the extracellular space by damaged cells and by the Pannexin1 channel protein and limited by the hydrolysis of extracellular ATP by ecto-ATPases. P2X7 and P2Y2 receptors are necessary for the initiation of cell migration, actin reorganization, and cell to cell communication required for the sheet like migration found within the corneal epithelium wound response. ARL 67156 Trisodium Salt Hydrate, an inhibitor for human and murine ecto-ATPases, was used to inhibit the hydrolysis of extracellular ATP during the wound response to prolong and further elevate extracellular ATP concentrations to increase the cellular activity and cell to cell communication of the wound response. The goal was to compare primary diabetic murine and human cells. However, there were issues with culturing these cells and diabetic murine and non-diabetic primary and established human cells were used for these experiments. Significant increases in cellular activity were found in both primary human cells with a 100 ARL to 10 ATP concentration ratio while no significant changes in cellular activity were found with the murine diabetic cells at any ARL concentration. In summary, with increased ATP in the wound response due to the inhibition of hydrolysis enzymes, human cells displayed increased levels and rates of cell-to-cell communication during the delayed wound response. / 2024-01-27T00:00:00Z

In our study, the decrease of H2O2 levels in wounding-treated tissues of soybean ( Glycine Max ) hypocotyls is accompanied by the enhancement of the POD activity. The POD activity was significantly enhanced 0.5 d after wounding treatment. The laccase activity was significantly enhanced 1-2 d after wounding treatment. The enhancement of POD by mechanical wounding occurred a day earlier than laccase. The increase in activities of POD and laccase is correlated with a rise in lignin contents in wounding-treated tissues. We suggest that in control tissues, laccase might play major role on the lignin biosynthesis, hence, POD by utilizing H2O2 play the major role on the lignin biosynthesis during the wounding process.

Intact strawberry fruit did not produce detectable t-2-H which is derived from -linolenic acid (18:3). However, in response to wounding by gentle bruising, strawberry fruit emitted t-2-H with the largest quantity produced within 10 min following injury. The level of total lipid 18:3 in the fruit increased two-fold in response to wounding whereas free 18:3 declined slightly (about 30%). At 10 min following wounding, fruit exhibited a 25% increase in 13-lipoxygenase (LOX) activity, which leads to the production of 13-hydroperoxyoctadecatrienoic acid (13-HPOT) from 18:3. The activity of hydroperoxide lyase (HPL), which catalyzes formation of cis-3-hexenal (c-3-H), the precursor of t-2-H, from 13-HPOT, increased two-fold at 10 min after wounding. Thus, within 15 min after wounding, free 18:3 substrate availability and the activity of two key enzymes, LOX and HPL, changed in a manner consistent with increased t-2-H biosynthesis. The site and mode of interaction of C6 aldehydes with Botrytis cinerea, a common pathogen of many plant species, was characterized using radiolabeled six carbon (C6) aldehydes, including c-3-H and t-2-H. An approximately 25% molar conversion of 18:3 to C6 aldehydes was obtained by enzymatic manipulation with LOX and HPL extracts. Following exposure of Botrytis cultures to radiolabeled aldehydes, radiolabeled aldehydes were recovered in protein fractions, but not in the lipid fraction. They were incorporated into conidia at a 20-fold higher level than mycelia (per mg fresh weight). About 95% of the radiolabeled aldehyde was recovered in proteins on the surface (wash protein) of the fungal tissue, while 5% was from protein in internal tissue (cell wall and membrane and cytosol). Supplementing radiolabeled aldehydes with nonradiolabled C6 aldehydes to increase the vapor phase concentration affected distribution of radiolabel in each protein fraction. The t-2-H at both 5.4 and 85.6 mol affected protein expression patterns, changing the intensity of expression in over one third of all proteins. Both up- and down-regulation of specific proteins were observed. Though five proteins of interest were analyzed, their identities were not determined. However, the data indicate a clear effect of t-2-H on protein expression in Botrytis cinerea.

The focal point in this study is the pastoral counselling and care of the heavy-hearted or depressed teenager who struggles with fear. The basic-theoretical perspective (chapter 2) emphasises the importance of counselling of the teenager from a Biblical viewpoint to be a testimony of the greatness of God. The fear that the teenager suffers from, is also described as the enemy who poses a threat to the inner being of the person. Therefore this type of threat can often lead to the total destruction of the inner being of a teenager. An intimate relationship with God enables a person to seek refuge in God from any problem he or she might experience. This relationship with God will guarantee the person of His full protection. It is of the utmost importance for an adolescent to seek wisdom and follow their parental guidelines. It is also important for young people to make the correct choices to enjoy the protection and guidance of God. They must also continually ponder over and treasure the guidance of their parents. The meta-theoretical perspective (chapters 3 and 4) focusses on the contribution and applicability of neighbouring sciences such as psychology, sociology and criminology. It was proven among other aspects that emotional hurt in different areas, was the reason for serious damage to the inner being of teenagers. In many cases the result was amongst others an identity crisis as well as a low self-esteem. At the end of this section temporary guidelines are suggested to aid the counselling of the depressed teenager who suffers from excessive fear. The section on empirical research (chapter 4) as a sub-section of the meta-theoretical research, introduced four case-studies regarding teenagers who had traumatic experiences and as a result suffered from multiple negative emotions. In all four cases it became evident that these emotions were eventually the result of a life without any joy or meaning. A very important factor regarding their negative self-image or self-perception seemed to be the absence of role-models. The further result repeatedly seemed to be a distorted relationship with God and fellow-men. In the section on practical-theoretical perspectives (chapter 5) an attempt is made to formulate an adapted practice theory through a hermeneutical interaction between basis-theoretical guidelines and meta-theoretical perspectives that can be applied to the guidance of the emotionally wounded teenager who is wrestling with fear. Included hereby is then a proposed model with some practical guidelines. / Thesis (MA (Pastoral Studies))--North-West University, Potchefstroom Campus, 2013.

The focal point in this study is the pastoral counselling and care of the heavy-hearted or depressed teenager who struggles with fear. The basic-theoretical perspective (chapter 2) emphasises the importance of counselling of the teenager from a Biblical viewpoint to be a testimony of the greatness of God. The fear that the teenager suffers from, is also described as the enemy who poses a threat to the inner being of the person. Therefore this type of threat can often lead to the total destruction of the inner being of a teenager. An intimate relationship with God enables a person to seek refuge in God from any problem he or she might experience. This relationship with God will guarantee the person of His full protection. It is of the utmost importance for an adolescent to seek wisdom and follow their parental guidelines. It is also important for young people to make the correct choices to enjoy the protection and guidance of God. They must also continually ponder over and treasure the guidance of their parents. The meta-theoretical perspective (chapters 3 and 4) focusses on the contribution and applicability of neighbouring sciences such as psychology, sociology and criminology. It was proven among other aspects that emotional hurt in different areas, was the reason for serious damage to the inner being of teenagers. In many cases the result was amongst others an identity crisis as well as a low self-esteem. At the end of this section temporary guidelines are suggested to aid the counselling of the depressed teenager who suffers from excessive fear. The section on empirical research (chapter 4) as a sub-section of the meta-theoretical research, introduced four case-studies regarding teenagers who had traumatic experiences and as a result suffered from multiple negative emotions. In all four cases it became evident that these emotions were eventually the result of a life without any joy or meaning. A very important factor regarding their negative self-image or self-perception seemed to be the absence of role-models. The further result repeatedly seemed to be a distorted relationship with God and fellow-men. In the section on practical-theoretical perspectives (chapter 5) an attempt is made to formulate an adapted practice theory through a hermeneutical interaction between basis-theoretical guidelines and meta-theoretical perspectives that can be applied to the guidance of the emotionally wounded teenager who is wrestling with fear. Included hereby is then a proposed model with some practical guidelines. / Thesis (MA (Pastoral Studies))--North-West University, Potchefstroom Campus, 2013.

No description available.

Stress-induced changes in the emissions of volatiles from many economically-important plants have been demonstrated in studies over the past decade. Plants such as cotton and corn change both the composition and concentration of their emissions when subjected to wounding, herbivory and pathogen attack. Terpene-accumulating plants have been overlooked as potential objects of such studies although work on conifers has shown that species rich in constitutive defences can also exhibit induced responses. The aim of this study was to investigate whether terpene-accumulating plants respond to stress by altering their foliar emissions qualitatively and/or quantitatively. Species examined included Salvia officinalis (common sage), Melaleuca alternifolia (Australian tea tree) and Ocimum minimum (Bush basil). An experimental design was developed to eliminate factors such as leaf ontogeny that can affect the obtained results and complicate their interpretation. Small-scale solvent extraction and HS-SPME-based techniques were also developed; they enabled the quantitative determination of treatment-induced changes over periods ranging from 10 minutes to 6 months. Treatment of plants included mechanical wounding, herbivory, pathogen attack and chemical elicitation. Overall, statistically significant induced-changes were observed for both leaf-oil composition and concentration. The response of the different species used varied. O. minimum exhibited the greatest compositional changes whilst M. alternifolia was the only species for which oil-concentration changes were observed. The demonstrated changes were not as great as those reported in similar studies with non-terpene producing plants. The results indicate that the high metabolic costs associated with the production and storage of constitutive defences may be responsible for the limited induction of further defensive responses / Doctor of Philosophy (PhD)