Ruxolitinib Adherence in Myelofibrosis and Polycythemia Vera: the “RAMP” Italian multicenter prospective study

Ruxolitinib is beneficial in patients with myelofibrosis (MF) and polycythemia vera (PV). Information on ruxolitinib adherence is scant. The Ruxolitinib Adherence in Myelofibrosis and Polycythemia Vera (RAMP) prospective multicenter study (NCT06078319) included 189 ruxolitinib-treated patients. Patients completed the Adherence to Refills and Medications Scale (ARMS) and Distress Thermometer and Problem List (DTPL) at the earliest convenience, after registration in the study, and at later timepoints. At week-0, low adherence (ARMS > 14) and high distress (DT ≥ 4) were declared by 49.7% and 40.2% of patients, respectively. The main reason for low adherence was difficult ruxolitinib supply (49%), intentional (4.3%) and unintentional (46.7%) non-take. In multivariable regression analysis, low adherence was associated to male sex (p = 0.001), high distress (p < 0.001), and treatment duration ≥ 1 year (p = 0.03). Over time, rates of low adherence and high distress remained stable, but unintentional non-take decreased from 47.9% to 26.0% at week-48. MF patients with stable high adherence/low distress were more likely to obtain/maintain the spleen response at week-24. Low adherence to ruxolitinib represents an unmet clinical need that require a multifaceted approach, based on reason behind it (patients characteristics and treatment duration). Its recognition may help distinguishing patients who are truly refractory and those in need of therapy optimization

In vitro mycorrhization of micropropagated plants: studies on Castanea sativa Mill.

In vitro mycorrhization can be made by several axenic and nonaxenic techniques but criticism exists about their artificiality and inability to reproduce under natural conditions. However, artificial mycorrhization under controlled conditions can provide important information about the physiology of symbiosis. Micropropagated Castanea sativa plants were inoculated with the mycorrhizal fungus Pisolithus tinctorius after in vitro rooting. The mycorrhizal process was monitored at regular intervals in order to evaluate the mantle and hartig net formation, and the growth rates of mycorrhizal and nonmycorrhizal plants. Plant roots show fungal hyphae adhesion at the surface after 24 hours of mycorrhizal induction. After 20 days a mantle can be observed and a hartig net is forming although the morphology of the epidermal cells remains unaltered. At 30 days of root–fungus contact the hartig net is well developed and the epidermal cells are already enlarged. After 50 days of mycorrhizal induction, growth was higher for mycorrhizal plants than for nonmycorrhizal ones. The length of the major roots was lower in mycorrhizal plants after 40 days. Fresh and dry weights were higher in mycorrhizal plants after 30 days. The growth rates of chestnut mycorrhizal plants are in agreement with the morphological development of the mycorrhizal structures observed at each mycorrhizal time. The assessment of symbiotic establishment takes into account the formation of a mantle and a hartig net that were already developed at 30 days, when differences between fresh and dry weights of mycorrhizal and nonmycorrhizal plants can be quantified. In vitro conditions, mycorrhization influences plant physiology after 20 days of root–fungus contact, namely in terms of growth rates. Fresh and dry weights, heights, stem diameter and growth rates increased while major root growth rate decreased in mycorrhizal plants.Springe

Effect of some plant flavonoids on in vitro behaviour of an arbuscular mycorrhizal fungus

The effect of 2 isoflavonoids (the soybean phytoalexin, glyceollin I, and the coumestan, coumestrol) and 1 flavonoid, quercetin, were tested on in vitro spore germination of Gigaspora margarita. Glyceollin I and coumestrol were tested at 0, 0.05, 0.5, 5 and 50 μM in water agar containing 0.5% ethanol. Quercetin was tested at 0, 0.1, 1 and 10 μM in pure water agar. All germination parameters were measured after 5 and 7 d. Germination rate was not significantly affected by any of these compounds. The number of germ tubes per spore was slightly increased by glyceollin I; mycelium length from germinated spores was increased by low concentrations of glyceollin I but was significantly decreased at the highest concentration. A positive correlation was found between coumestrol concentration and mycelium length, and vesicle number was decreased by coumestrol, quercetin and the highest concentration of glyceollin but was increased by glyceollin at 0.5 μM. Results are discussed in relation to the potential of flavonoids and isoflavonoids in acting as regulatory factors in plant-AM fungus interactions.Effet de la glycéolline I, du coumestrol et de la quercétine sur le comportement in vitro de Gigaspora margarita. Deux isoflavonoïdes (la glycéolline I et le coumestrol) et un flavonoïde (la quercétine) ont été éprouvés vis-à-vis de la germination in vitro de Gigaspora margarita. Les expériences ont été faites en utilisant les concentrations de 0, 0,05, 0,5, 5 et 50 μmol.l -1 dans l'eau gélosée contenant 0,5% d'éthanol pour les premiers et de 0, 0,1, 1, et 10 μmol.l -1 dans l'eau gélosée pure pour la quercétine. Les mesures, réalisées après 5 et 7 j de croissance ont montré que le taux de germination n'a été affecté par aucun des composés, que le nombre de tubes germinatifs a été légèrement augmenté par la glycéolline I et que la longueur du mycélium par spore germée a été augmentée par la glycéolline I aux faibles concentrations alors qu'elle a été significativement diminuée à concentration supérieure. Une corrélation positive a été trouvée entre la teneur en coumestrol et la longueur du mycélium des tubes germinatifs. Les résultats sont discutés en relation avec la potentialité des flavonoïdes et isoflavonoïdes d'agir comme régulateurs dans le processus infectieux du champignon mycorhizien

Influence of phosphate fertilization on the growth and nutrient status of micropropagated apple infected with endomycorrhizal fungi during the weaning stage

Microplants of 2 apple rootstocks (M9, M26) and one cultivar (Golden) were inoculated with VAM fungi during a very early weaning stage of acclimatization following micropropagation and supplied with nutrient solution at different P concentrations. Phosphate fertilization containing a high level of P (40 ppm) had no effect on the growth response of mycorrhizal apple plants. At the lower levels of 8 and 4 ppm P mycorrhizal plants maintained the same growth rate as with 40 ppm P. Phosphate fertilization had no influence on endomycorrhizal infection. No difference was observed in the mineral contents of mycorrhizal and nonmycorrhizal plants, or between plants receiving different levels of P. At the lower fertilization rates of P, endomycorrhizal infection not only improved growth but also homogeneity of Golden and M26 plants.Des microplantes de 2 porte-greffes de pommier (M9, M26) et d’un cultivar (Golden) ont été inoculés avec des champignons VAM pendant une phase très précoce de l’acclimatation, après la micropropagation, et ont reçu des solutions nutritives comprenant des doses variables de P. La fertilisation phosphatée à un niveau élevé de P (40 ppm) n’a pas eu d’effet sur la réponse de croissance de plantes de pommiers mycorhizées. A des niveaux plus faibles de 8 et 4 ppm (P) les plantes mycorhizées ont la même vitesse de croissance que celles recevant 40 ppm de P. La fertilisation phosphatée n’a pas eu d’influence sur l’infection mycorhizienne. On n’a observé aucune différence entre la composition minérale des plantes mycorhizées et celle des plantes qui ne l’étaient pas, ni entre celles de plantes ayant reçu différentes doses de P. Aux bas niveaux de fertilisation phosphatée, l’infection mycorhizienne a amélioré non seulement la croissance, mais aussi l’homogénéité de Golden et de M26

In vitro enhancement of spore germination and early hyphal growth of a vesicular-arbuscular mycorrhizal fungus by host root exudates and plant flavonoids

International audienc

Interazione Collemboli-funghi fitopatogeni-funghi AM: risultati preliminari.

Il terreno è un serbatoio di organismi che interagiscono fra di loro. Tali interazioni sono molto importanti per lo sviluppo delle piante e per il loro stato sanitario: I collemboli rappresentano una componente importante degli animali del suolo; sono prevalentemente fungivori e si nutrono, oltre che di funghi, della sostanza organica su cui i propaguli fungini si trovano. Fra i funghi del suolo, i collemboli interagiscono sia con i funghi fitopatogeni, sia con quelli micorrizici arbuscolari. Numerosi studi hanno esaminato l’interazione collemboli-funghi fitopatogeni, la maggior parte dei lavori ha evidenziato un effetto di contenimento da parte degli animali dell’attività parassitaria dei funghi patogeni. Meno studiata è l’interazione collemoli-funghi micorrizici arbuscolari (AM). Nel presente studio è stato valutato l’effetto dell’interazione del collembolo Protaphorura armata (Pa), del fungo patogeno Fusarium culmorum (Fc), e del fungo AM Glomus intraradices (Gi), su piante di frumento duro cv Creso in prove svolte in vasi di Leonard di plastica posti in ambiente controllato. In ogni vaso (1,5 l) sono stati posti 400 g di substrato costituito da terreno di campo sterile + sabbia di fiume sterile + torba sterile (1:1:0,5 vol:vol:vol), cui è stato aggiunto, quando previsto, l’inoculo commerciale di G. intraradices (1% peso). In ogni vaso sono stati trapiantati sei semenzali di frumento: Dopo 4 settimane è stato eseguito il controllo della micorrizazione, quindi sono stati aggiunti al substrato di crescita delle piante, l’inoculo del patogeno (1% in peso; cstituito da cariossidi sterili di frumento colonizzate da Fc) e 110 esemplari di Pa. Dopo due settimane, le piante sono state raccolte e sono stati determinati l’indice di malattia e il peso secco. Dal substrato sono stati estratti per flottazione gli animali che sono stati contati e successivamente fissati per l’esame del contenuto intestinale. Dai dati ottenuti è emersa compatibilità fra la presenza dei collemboli e l’effetto di biofertilizzazione e di biocontrollo del fungo AM

Interazioni Collemboli-funghi terricoli: quale effetto sulla salute delle piante?

Collembola are mostly mycophagous animals living in the upper soil layers where they interact with propagules of plant pathogenic, antagonistic and mutualistic fungi, therefore their feeding activity can indirectly influence the plant health. In the present work interactions between the collembolan Protaphorura armata and i) the arbuscula mycorrhizal fungus glomus intraradices, ii) the antagonistic fungus Trichoderma harzianum against the disease caused by the pathogenic fungi Gaeumannomyces graminis var. tritici o Fusarium culmorum respectively on wheat plants were studied in microcosms under controlled conditions

Response of plant growth to Collembola, arbuscular mycorrhizal and plant pathogenic fungi interactions

Effects of interactions of the collembolan Protaphorura armata, the arbuscular mycorrhizal fungus Glomus intraradices and the foot and root pathogenic fungus Fusarium culmorum on growth and health of wheat plants were studied in modified Leonard bottle-jars containing sterile sand and peat. The mycorrhizal colonisation, the root and shoot dry weight and the disease index were determined. Also the number of adult Collembola was determined and their gut content analysed. The presence of Collembola did not decrease the positive effect of the arbuscular mycorrhizal fungus Glomus intraradices on the plant biomass and did not reduce the biocontrol capacity of this fungus

Trophic interactions of soil fungi and Collembola

Results of our studies on interactions between different species of soil fungi and collembola in vitro, and in planta are summarised. The feeding preference of collembolan Protaphorura armata, Mesaphorura krausbaueri, Onychiurus tuberculatus, and Folsomia candida were investigated in Petri dishes, each containing contemporaneously Fusarium culmorum (Fc), Gaeumannomyces graminis var. tritici (Ggt), Bipolaris sorokiniana (Bs) and Rhizotonia cerealis (Rc) colonies. In some experiments Bs was replaced by Trichoderma harzianum (Th). All springtails grazed preferably on the mycelium of Fc, but Ggt and Rc hyphae were also consumed. Bs mycelium had repellent and/or lethal effect on animals, Th mycelium was repellent, whereas conidia of both fungi were palatable. A diet based on Fc, Ggt, and Rc mycelium or Bs conidia showed different impact on the life processes of M. krausbaueri. The fate of conidia during gut passage was also considered. The majority of Th conidia were not damaged during transit through the gut, and thus they were viable and formed colonies. On the contrary, transit through gut damaged the conidia of Fc. In planta studies have shown that P. armata significantly controlled disease caused by Fc or Ggt on wheat seedlings. The compatibility between Th and springtails in presence of Ggt was also investigated in in planta assays. It has been observed that when Th propagules coated wheat seeds, springtails showed biocontrol effect against Ggt disease. On the contrary, when Th inoculum was mixed with the substrate of plant growth, the animals were not able to control disease severity. In all experiments the biomass of wheat plants was not reduced by springtails