KNOCK-OUT DI UN GENE CODIFICANTE UNA ENDO-β1, 4-XILANASI DEL FUNGO FITOPATOGENO FUSARIUM GRAMINEARUM

Durante il processo infettivo, i funghi fitopatogeni secernono nelle cellule della pianta ospite vari enzimi degradativi tra i quali le xilanasi, che sono state dimostrate essere importanti fattori di virulenza in specifiche interazioni pianta-patogeno (Brito et al., 2006; Nguyen et al., 2011). Fusarium graminearum e' un fungo patogeno responsabile di una malattia nota come Fusariosi della spiga (FHB) che colpisce importanti specie cerealicole quali il frumento. Durante l'infezione di piante di frumento, il fungo e' stato dimostrato causare una forte degradazione enzimatica dello xilano di parete (Wanyoike et al. 2002). Recenti studi di trascrittomica e di proteomica hanno inoltre evidenziato il possibile coinvolgimento di alcune endo-ò-1,4-xilanasi di F. graminearum nelle prime fasi del processo infettivo della pianta ospite frumento. Sebbene questi studi sostengano la potenziale importanza delle xilanasi di F. graminearum, il loro ruolo resta ancora da chiarire. Dati di analisi di espressione ottenuti nel laboratorio dove ho svolto la tesi hanno inoltre dimostrato che il gene Fgsg_11487, codificante una delle endo-ò-1,4-xilanasi di F. graminearum, e' uno dei piu' espressi in spighette di frumento infette. Il lavoro svolto nella presente tesi prevede l'ottenimento di mutanti knock-out del gene Fgsg_11487 per poterne in futuro verificare il ruolo nel processo infettivo. Dai risultati ottenuti si e' concluso che solamente in un mutante (SPLIT 13) e' avvenuta la corretta trasformazione, con la distruzione del gene Fgsg_11487 e l'integrazione del gene marker di selezione (resistenza all'antibiotico igromicina) mediante un evento di ricombinazione omologa sito-specifica. L'ottenimento di un mutante knock-out vitale privato del gene d'interesse ha confermato che questa xilanasi non ha nessun ruolo essenziale nel regolare le funzioni vitali del fungo F. graminearum. Il mutante verra' in futuro caratterizzato mediante prove d'infezione su spighe di frumento per poter verificare l'effetto del knock-out di questa xilanasi sulla virulenza del mutante

Anorexia Nervosa and Body Fat Distribution: A Systematic Review

The aim of this paper was to conduct a systematic review of body fat distribution before and after partial and complete weight restoration in individuals with anorexia nervosa. Literature searches, study selection, method development and quality appraisal were performed independently by two authors, and data was synthesized using a narrative approach. Twenty studies met the inclusion criteria and were consequently analyzed. The review had five main findings. First, during anorexia nervosa adolescent females lose more central body fat, while adult females more peripheral fat. Second, partial weight restoration leads to greater fat mass deposition in the trunk region than other body regions in adolescent females. Third, after short-term weight restoration, whether partial or complete, adults show a central adiposity phenotype with respect to healthy age-matched controls. Fourth, central fat distribution is associated with increased insulin resistance, but does not adversely affect eating disorder psychopathology or cause psychological distress in female adults. Fifth, the abnormal central fat distribution seems to normalize after long-term maintenance of complete weight restoration, indicating that preferential central distribution of body fat is a transitory phenomenon. However, a discrepancy in the findings has been noted, especially between adolescents and adults; besides age and gender, these appear to be related to differences in the methodology and time of body composition assessment

Self-Care for Common Colds: The Pivotal Role of Vitamin D, Vitamin C, Zinc, and Echinacea in Three Main Immune Interactive Clusters (Physical Barriers, Innate and Adaptive Immunity) Involved during an Episode of Common Colds - Practical Advice on Dosages and on the Time to Take These Nutrients/Botanicals in order to Prevent or Treat Common Colds

Maintaining a normal healthy immune defense system lowers the incidence and/or the severity of symptoms and/or the duration of common cold (CC). Physical barriers and innate and adaptive immunity have been involved during a CC episode. Vitamins C and D, zinc, and Echinacea have evidence-based efficacy on these immune system barriers. This review includes 82 eligible studies to consider the preventive role of these nutrients in immune clusters and in CC to provide advice on dosage and assumption of these nutrients. Regarding vitamin C, regular supplementation (1 to 2 g/day) has shown that vitamin C reduces the duration (in adults by 8%, in children by 14%) and the severity of CC. Considering zinc, the supplementation may shorten the duration of colds by approximately 33%. CC patients may be instructed to try zinc within 24 hours of onset of symptoms. As for vitamin D, the supplementation protected against CC overall, considering baseline levels and age. Patients with vitamin D deficiency and those not receiving bolus doses experienced the most benefit. Regarding Echinacea, prophylactic treatment with this extract (2400 mg/day) over 4 months appeared to be beneficial for preventing/treating CC. In conclusion, the current evidence of efficacy for zinc, vitamins D and C, and Echinacea is so interesting that CC patients may be encouraged to try them for preventing/treating their colds, although further studies are needed on this topic

Anorexia Nervosa and Body Fat Distribution: A Systematic Review

The aim of this paper was to conduct a systematic review of body fat distribution before and after partial and complete weight restoration in individuals with anorexia nervosa. Literature searches, study selection, method development and quality appraisal were performed independently by two authors, and data was synthesized using a narrative approach. Twenty studies met the inclusion criteria and were consequently analyzed. The review had five main findings. First, during anorexia nervosa adolescent females lose more central body fat, while adult females more peripheral fat. Second, partial weight restoration leads to greater fat mass deposition in the trunk region than other body regions in adolescent females. Third, after short-term weight restoration, whether partial or complete, adults show a central adiposity phenotype with respect to healthy age-matched controls. Fourth, central fat distribution is associated with increased insulin resistance, but does not adversely affect eating disorder psychopathology or cause psychological distress in female adults. Fifth, the abnormal central fat distribution seems to normalize after long-term maintenance of complete weight restoration, indicating that preferential central distribution of body fat is a transitory phenomenon. However, a discrepancy in the findings has been noted, especially between adolescents and adults; besides age and gender, these appear to be related to differences in the methodology and time of body composition assessments. The PROSPERO Registry—Anorexia Nervosa and Body Fat Distribution: A Systematic Review (CRD42014008738)