Trend of sexually transmitted infections during the Covid-19 age. What was the impact of the pandemic and the social distancing measures?

Covid-19 pandemic has led to social distancing guidelines andresource allocation with subsequent impairment of sexual healthservices. The impact of such measures and the recommendationsregarding changes of sexual behaviour is a matter of debate

Seiricardine-b and Seiricardine-c, Phytotoxic Sesquiterpenes From 3 Species of Seiridium Pathogenic For Cypress

Seiricardines B and C, two tricyclic toxic sesquiterpenes, were isolated from culture filtrates of Seiridium cardinale, S. cupressi and S. unicorne, three fungi associated with canker disease of cypress (Cupressus sempervirens) in the Mediterranean area. These new toxic compounds are produced in addition to the already known toxins: seiridin, isoseiridin, seiricuprolide, cyclopaldic acid and seiricardine A. Seiricardine B and C are epimeric diastereomers; their structures and those of some key derivatives were established by spectral studies. Assayed on severed twigs of cypress, seiricardine B and C caused leaf chlorosis followed by browning, and chlorosis, respectively; whereas on tomato and bean cuttings they caused chlorosis and necrosis, and chlorosis, respectively. After injection of seiricardine B and C into cortical tissues of young cypress plants, a hypertrophic reaction of the tissues adjacent to the site of injection and a reddish discolouration of distal leaves, and a reddening and longitudinal lesions, respectively, were observed. In the antimicrobial assay, seiricardine B, in comparison to seiricardine C, showed a higher inhibitory effect on mycelial growth of three test fungi

Degradazione di resveratrolo ed acido tannico da parte di Phaeomoniella chlamydospora, Phaeocremonium aleophilum e Fomitiporia mediterranea, funghi associati al mal dell’esca della vite

Numerose prove d’infezione hanno portato ad attribuire un ruolo di patogeni primari, nella sindrome del mal dell’esca, a tre funghi più comuni nelle condizioni dei nostri vigneti: Phaeomon iella chlamydospora (Pch) e Phaeoacremonium aleophilum (telomorfo: Togninia minina) (Paf) per le “venature brune” e Fomit4poria mediterranea (Fme) per la carie del legno. E’ noto che la vite è pianta ricca di polifenoli. Questi composti possono subire variazioni in seguito all’esposizione dei tessuti all’azione di agenti biotici o abiotici sfavorevoli od essere il prodotto (fitoalessine) di meccanismi di resistenza. Ad esempio, la concentrazione di flavanoli e stilbeni aumenta nelle viti che hanno subito infezioni di varia natura, rispetto alle viti sane. Non si conosce l’effetto che questi composti hanno sui funghi colonizzatori del legno, e tantomeno se gli stessi composti partecipino in qualche modo all’espressione dei sintomi. E’ però probabile che questi ed altri prodotti di reazione della pianta, accumulandosi nel legno attorno alle zone invase o traslocati nelle foglie, formino barriere chimiche limitanti lo sviluppo di funghi ad essi sensibili. I dati presentati in questa Nota riguardano le ricerche condotte sui tre più importanti funghi associati al mal dell’esca, al fme di verificare le loro capacità di degradare il transresveratrolo (RES) nei calli di vite, di utilizzare RES e acido tannico (AT) in colture liquide o agarizzate come unica fonte di carbonio organico ed infine di produrre fitotossine (isosclerone e scitalone) in colture liquide contenente RES o in associazione con glucosio. E’ stata determinata la concentrazione di RES nelle foglie di due varietà di viti ‘Italia’ e ‘Matilde’, in tre diversi stadi fenologici e si è constatato che la cv. Italia contiene più RES della cv. Matilde. Analogamente è stata calcolata la concentrazione di RES nei calli delle stesse varietà. Anche nei calli, la concentrazione di RES della cv. Italia è risultata maggiore di quella della cv. Matilde. Inòltre, il contenuto di RES nei calli di ‘Italia’ inoculati con Pal, Pc/i e Fme è risultato minore di quello dei relativi controlli; nel caso della ‘Matilde’, solo nei calli inoculati con Palla concentrazione di RES è stata maggiore del controllo. Pc/i, Pal e Fme coltivati in coltura liquida o agarizzata contenente RES, nell’intervallo di concentrazioni 10—220 ug/mL, hanno degradato lo stilbene. Il RES (a concentrazioni >50 ug/ml) ha causato la riduzione del tasso di crescita dei tre funghi. Pch, Pa! e Fme sono stati coltivati anche in colture liquide o agarizzate contenenti solo AT o AT e glucosio. E’ stato osservato che l’AT come unica fonte carboniosa è sufficiente a sostenere la crescita dei tre funghi. In presenza di glucosio nel mezzo nutritivo, l’AT ha esercitato una riduzione del tasso di crescita delle tre specie fungine, a mano a mano crescente, a partire dalla concentrazione di 1 mg ml. Pal e Pch hanno prodotto scitalone ed isosclerone in colture liquide contenenti solo RES o RES e glucosio come uniche fonti carboniose. La produzione dei due pentachetidi èiniziata a partire dal settimo giorno d’incubazione. Pal ha prodotto scitalone in quantità maggiori di quelle del Pch; il RES ha ridotto drasticamente la produzione di scitalone da parte di Pa! e Pc/i. 11 RES da solo o insieme al glucosio ha stimolato la produzione di isosclerone in entrambi i funghi. Sembra che la presenza di RES nel substrato riduca la produzione di scitalone ed incrementi quella di isosclerone. Questo dato conforta l’ipotesi che essendo inibita o rallentata la via biosintetica delle melanine, si formi strada facendo più isosclerone, prodotto di ossidazione dell’intermedio l,3,8-triidrossinaftalene

7'-hydroxyseiridin and 7'-hydroxyisoseiridin, 2 New Phytotoxic Delta(alpha,beta)-butenolides From 3 Species of Seiridium Pathogenic To Cypresses

Two new phytotoxic Delta(alpha,beta)-butenolides, 7'-hydroxyseiridin [1] and 7'-hydroxyisoseiridin [2], were isolated from culture filtrates of three species of Seiridium (S. cardinale, S. cupressi, and S. unicorne). These fungi are associated with the canker diseases of cypress trees (Cupressus sempervirens) in the Mediterranean area. The structures of butenolides 1 and 2 were established using spectroscopic and chemical methods in comparison with seiridin [5] and isoseiridin [6], two phytotoxic metabolites produced in higher concentration by the same fungal species. Necrotic and chlorotic symptoms were produced on cuttings of both host and non-host plants by absorption of 100 or 50 mu M solutions, respectively, of compounds 1 and 2

Effects of three esca-associated fungi on Vitis vinifera L. III. Enzymes produced by the pathogens and their role in fungus-to-plant or in fungus-to-fungus interactions

When the esca-associated fungi Phaeomoniella chlamydospora (Pch), Togninia minima (Tmi) and Fomitiporia mediterranea (Fme) were grown in liquid stationary cultures, it was seen that they were able to live in media containing resveratrol (RES) or tannic acid (TA) as the sole carbon source and that the fungi were able to convert both compounds. Particular attention is paid here to detecting RES and TA conversion. Pch, Tmi and Fme were partially inhibited by RES or TA. Pch, Tmi and Fme produced extracellular tannase, laccase and peroxidase enzymes in liquid or agarized cultures, whether glucose was present or not. When colonies of Pch, Tmi and Fme were confronted, they showed spatially and temporally heterogeneous patterns of laccase and peroxidase activity. The results indicate the nonsynergistic, competitive association of Pch and Tmi and the inhibition of Fme growth. Muconic acid, a well-known intermediate in a large number of lignin and phenol oxidative processes, can partly or completely inhibit the lignolytic agent Fme, but is tolerated by Pch and Tmi. An explanation for wood pigmentation patterns by Pch, Tmi and Fme is given

Effects of three esca-associated fungi on Vitis vinifera L. I. Characterization of secondary metabolites in culture media and host responses to the pathogens in calli

Phaeomoniella chlamydospora (Pch) and Togninia minima (Tmi) produced scytalone, isosclerone and pullulans in liquid cultures, as well as in calli. Secondary metabolites and host defense compounds were shown to occur in calli of Vitis vinifera cv. Italia and cv. Matilde infected by the esca-associated fungi Pch, Tmi and Fomitiporia mediterranea (Fme). Calli of both cvs. were grown as dual cultures with Pch, Tmi and Fme. The fungi grew well in the presence of calli of both cvs., but callus growth was reduced. Accumulation and changes of total phenolics and recurring phenolics, and of two phytotoxic pentaketides and pullulans were analyzed by HPLC. On comparing results for cv. Italia and cv. Matilde, it can be seen that concentrations of phenolics are strongly related to the cv. The paper discusses the possible relationship between melanin biosynthesis in Pch and Tmi, which utilize pentaketide metabolites as intermediates and their pathogenicity related to phytotoxity of scytalone and isosclerone

Use of fusicoccin in the early selection of durum wheat for tolerance to water stress

The use of the fungal metabolite fusicoccin (FC) to induce water stress in durum wheat for the early selection of drought-tolerant genotypes of durum wheat was investigated. The experiments were carried out in a plant-growth chamber using seedlings of two cultivars: Creso and Simeto. Several concentrations of FC (from 10-7 to 10-5 M) and different modes of application were compared. Changes in the water status of seedlings during the experiments were assessed by measuring variations in fresh weight, leaf water potential, relative water content and transpiration. The results indicated that, under the environmental conditions adopted (20°C, 65% RH, 80 µE m-2 s-1 continuous illumination), the best simulation of water stress was obtained using cuttings of durum wheat seedlings treated with 10-5 M FC solution (6.8 µg ml-1) for at least 24 hours. ‘Simeto’ tolerated FC-induced water stress better than ‘Creso’. This result agrees with previous data from both indoor and outdoor experiments in which other water stress agents were used