Antibiotikaresistenz/-toleranz und Evasion des menschlichen Immunsystem sind wesentliche Probleme persistierender chronischer Infektionen, die im Zusammenhang mit Biofilmen stehen. Eine Notwendigkeit alternativer Behandlungen liegt daher nahe. Für diese Studie wurden zehn ayurvedische Pflanzen ausgewählt, die die Produktion von Curli-Fasern und/oder pEtN-Cellulose in E. coli K-12 Makrokolonie-Biofilmen eindeutig hemmten. Eine Reihe molekularer Reporter wurde verwendet, um die molekularen Ziele im Modellorganismus E. coli zu identifizieren. Eine Kombination von mikrobiologischen, molekularbiologischen und enzymatischen Methoden und Experimenten wurde dann verwendet, um die Aktivitäten der Pflanzenextrakte weiter zu charakterisieren. Um ihre Wirkung auf Biofilme eines breiteren Spektrums von Bakterien zu testen, wurden einige relevante gramnegative Pathogene (EAEC, UPEC, P. aeruginosa) und grampositive Bakterien (B. subtilis, S. aureus) als Makrokolonie-Biofilme sowie als submerse Biofilme in Gegenwart der Pflanzenextrakte inkubiert. Die wichtigsten Ergebnisse dieser Studie sind, dass es kein „Allheilmittel“ gibt, das effektiv gegen verschiedene Biofilmstrukturen wirken kann. Es konnte gezeigt werden, dass fast alle Pflanzenextrakte die CsgA Amyloidogenese hemmen. Drei der zehn Pflanzenextrakte beeinflussten die Curli- und pEtN-Cellulose-Gene signifikant, indem sie csgB und dgcC über den Regulator CsgD herunterregulierten. Darüber hinaus wurde festgestellt, dass ein Extrakt die Expression flagellarer Gene in E. coli hochreguliert - eine neue Anti-Biofilm Strategie. Überraschenderweise wurde auch festgestellt, dass ein Pflanzenextrakt, das die Biofilmbildung des Kommensalen E. coli K-12 hemmt, während es die Biofilmbildung von UPEC fördert. Daher können Anti-Biofilm-Effekte stammspezifisch sein. Eine Strategie, bei der verschiedene Pflanzenextrakte kombiniert werden, könnte gegen Biofilme wirken, die aus mehreren Arten bestehen, erfordert jedoch weitere Forschung. / Antibiotic resistance/tolerance and evasion from the human immune system are major causes of concern associated with biofilm-related persistent chronic infections. So, the need for an alternative source of treatment is obvious. In this study, 10 Ayurvedic plants were selected as they clearly inhibited the production of curli fiber and pEtN-cellulose or of curli fibers only in E. coli K-12 macrocolony biofilms. A series of molecular reporters were used to determine the molecular targets using E. coli as model bacteria. A combination of microbiological, molecular biological, and enzymatic assays and experiments were then used to further characterize the activities of the plant extracts. To test anti-biofilm effects on a wider range of bacteria, some relevant Gram-negative pathogens (EAEC, UPEC, P. aeruginosa) and Gram-positive bacteria (B. subtilis, S. aureus) were grown in macrocolony biofilms and submerged biofilms in the presence of active plant extracts. The major findings of this study are that there is not one single “magic bullet” that can effectively work against the diverse biofilm compositions and structures. Nearly all plant extracts were found to inhibit CsgA amyloidogenesis. Three of the ten plant extracts affected the curli and pEtN-cellulose genes significantly by downregulating csgB and dgcC via the CsgD regulator. In addition, one extract was found to upregulate flagellar gene expression in E. coli - this is a new anti-biofilm strategy that had not considered before. Surprising, it was also noticed that one plant extract, which inhibits biofilm formation by commensal E. coli K-12, promotes biofilm formation by UPEC. Thus, anti-biofilm effects can be strain-specific because of the diversity of composition of the matrix within the same bacterial species. A strategy of combining different plant extracts may work to deal with biofilms involving multiple species, but requires more research and understanding.

Although thet:e has been gradual awat:eness of leat:ning disabilities aftet: Wodd Wat: II, it was in the late 1960's that compt:ehensive assessment and special education wet:e provided in schools. Specifically, in the at:ea of services for families, a reaffirmation of the fundamental rights of chilruen and families emerges. Although stress associated with the presence of a learning disabled child is an important consideration, its impact on the family is related to the family members' cognitive appraisal of the stress situation and thett copmg resources. Parents of learning disabled chilruen experience more stress, often exacerbated by faulty, misunderstood coping efforts that increase conflict in the family. Reseat:chers have investigated how: families manage stress; and cope with the multiple stt:esses of rearing a learning disabled children. It has been found that while many families cope, others cannot. Stress theory has dttected our attention to circumstances that weaken families and exacerbate distress. Preventative and ameliorative services at:e needed to assist such families. Stress and coping theory suggest that differences in families' reactions to learning disabilities may be related to amount and quality of resources available to pat:ents. This involves cognitive adaptation using coping skills, enabling them to t:e-evaluate stressful events positively. Another resource would be professionals, whose role would be of a facilitator, strengthening the ability of the family to gain access to needed services while increasing the family's mastery of coping with learning disability. Research has shown that parents' initial contact with learning disability and how to assist their learning disabled child was stressful. After parents received counselling on coping with their stress and stress management, and after the child's psycho-educational assessment and remedial measures were implemented, there has been significant positive feedback from parents and children. Research would embrace relationships between perceptions and family well-being using Ellis's rational-emotive therapy, thereby contributing to better understanding of how families cope with stress. Ayurvedic principles would be used to adopt a holistic approach to life. By using RET and A yurvedics the researcher was able to assist parents with learning disabled children to cope better with their stresses and effectively manage their child's learning disability. / Psychology of Education / D. Ed. (Psychology of Education)

Although thet:e has been gradual awat:eness of leat:ning disabilities aftet: Wodd Wat: II, it was in the late 1960's that compt:ehensive assessment and special education wet:e provided in schools. Specifically, in the at:ea of services for families, a reaffirmation of the fundamental rights of chilruen and families emerges. Although stress associated with the presence of a learning disabled child is an important consideration, its impact on the family is related to the family members' cognitive appraisal of the stress situation and thett copmg resources. Parents of learning disabled chilruen experience more stress, often exacerbated by faulty, misunderstood coping efforts that increase conflict in the family. Reseat:chers have investigated how: families manage stress; and cope with the multiple stt:esses of rearing a learning disabled children. It has been found that while many families cope, others cannot. Stress theory has dttected our attention to circumstances that weaken families and exacerbate distress. Preventative and ameliorative services at:e needed to assist such families. Stress and coping theory suggest that differences in families' reactions to learning disabilities may be related to amount and quality of resources available to pat:ents. This involves cognitive adaptation using coping skills, enabling them to t:e-evaluate stressful events positively. Another resource would be professionals, whose role would be of a facilitator, strengthening the ability of the family to gain access to needed services while increasing the family's mastery of coping with learning disability. Research has shown that parents' initial contact with learning disability and how to assist their learning disabled child was stressful. After parents received counselling on coping with their stress and stress management, and after the child's psycho-educational assessment and remedial measures were implemented, there has been significant positive feedback from parents and children. Research would embrace relationships between perceptions and family well-being using Ellis's rational-emotive therapy, thereby contributing to better understanding of how families cope with stress. Ayurvedic principles would be used to adopt a holistic approach to life. By using RET and A yurvedics the researcher was able to assist parents with learning disabled children to cope better with their stresses and effectively manage their child's learning disability. / Psychology of Education / D. Ed. (Psychology of Education)