Gain- and Loss-of-Function CFTR Alleles Are Associated with COVID-19 Clinical Outcomes

Carriers of single pathogenic variants of the CFTR (cystic fibrosis transmembrane conductance regulator) gene have a higher risk of severe COVID-19 and 14-day death. The machine learning post-Mendelian model pinpointed CFTR as a bidirectional modulator of COVID-19 outcomes. Here, we demonstrate that the rare complex allele [G576V;R668C] is associated with a milder disease via a gain-of-function mechanism. Conversely, CFTR ultra-rare alleles with reduced function are associated with disease severity either alone (dominant disorder) or with another hypomorphic allele in the second chromosome (recessive disorder) with a global residual CFTR activity between 50 to 91%. Furthermore, we characterized novel CFTR complex alleles, including [A238V;F508del], [R74W;D1270N;V201M], [I1027T;F508del], [I506V;D1168G], and simple alleles, including R347C, F1052V, Y625N, I328V, K68E, A309D, A252T, G542*, V562I, R1066H, I506V, I807M, which lead to a reduced CFTR function and thus, to more severe COVID-19. In conclusion, CFTR genetic analysis is an important tool in identifying patients at risk of severe COVID-19

Carriers of ADAMTS13 Rare Variants Are at High Risk of Life-Threatening COVID-19

Thrombosis of small and large vessels is reported as a key player in COVID-19 severity. However, host genetic determinants of this susceptibility are still unclear. Congenital Thrombotic Thrombocytopenic Purpura is a severe autosomal recessive disorder characterized by uncleaved ultra-large vWF and thrombotic microangiopathy, frequently triggered by infections. Carriers are reported to be asymptomatic. Exome analysis of about 3000 SARS-CoV-2 infected subjects of different severities, belonging to the GEN-COVID cohort, revealed the specific role of vWF cleaving enzyme ADAMTS13 (A disintegrin-like and metalloprotease with thrombospondin type 1 motif, 13). We report here that ultra-rare variants in a heterozygous state lead to a rare form of COVID-19 characterized by hyper-inflammation signs, which segregates in families as an autosomal dominant disorder conditioned by SARS-CoV-2 infection, sex, and age. This has clinical relevance due to the availability of drugs such as Caplacizumab, which inhibits vWF-platelet interaction, and Crizanlizumab, which, by inhibiting P-selectin binding to its ligands, prevents leukocyte recruitment and platelet aggregation at the site of vascular damage

Malattie fungine della vite

Sintesi della biologia e sintomatologia delle principali malattie fungine della vite e difesa. Esattamente peronospora, oidio, botrite, marciume acido, marciume nero, escoriosi e mal dell'esca

La difesa antiperonosporica per uve di qualità: nuovi prodotti ed evoluzione delle strategie.

La recente registrazione in Italia di tre nuovi antiperonosporici (nell’ordine fl uopicolide, valifenalate e mandipropamid) ha segnato un’ulteriore tappa della moderna evoluzione di tale categoria di fungicidi iniziata nei primi anni Ottanta del secolo scorso. Come è noto, i nuovi antiperonosporici introdotti in tale periodo hanno consentito di superare il tradizionale modello dei prodotti di «copertura» grazie alle innovative caratteristiche tecniche, che hanno sostanzialmente modifi cato l’approccio della difesa antiperonosporica della vite seguito nei primi cento anni della sua storia europea. Alla base di tale cambiamento vi era, innanzitutto, la capacità delle nuove molecole di penetrare nei tessuti vegetali e poiché..................

Oidio delle cucurbitacee: quali strategie di difesa

È una malattia diffusa sulle cucurbitacee in coltura protetta e in pieno campo e richiede spesso l’applicazione di trattamenti specifi ci. L’attuale disponibilità di sostanze attive è relativamente ampia, ma occorre prestare attenzione al rispetto del periodo di sicurezza e gestire correttamente l’impiego dei prodotti al fi ne di limitare il rischio di riduzione di sensibilità dei patogeni ai fungicid

Comparison of Alternaria spp. collected in Italy from apple with A. mali and other AM-toxin producing strains.

Since 1999, a disease of apple caused by an Alternaria sp. has been affecting orchards in northern Italy resulting in necrotic spots on leaves and on fruit. Forty-four single-spored isolates were obtained from diseased plant materials to investigate the diversity of this fungus in Italy and to compare these isolates to isolates of Alternaria associated with apple disease in previous studies, including A. mali, causal agent of apple blotch. All isolates, including the reference strains, were tested for pathogenicity utilizing in vitro bioassays on detached leaf or on fruit ('Golden Delicious'). In addition, morphological characterizations were conducted describing both the three-dimensional sporulation pattern and the colony morphology of each isolate. In order to assess the genetic diversity within the Italian Alternaria population, sequence characterization of specific loci and anonymous regions (endoPG, OPA1-3, OPA2-1, and OPA10-2) and genetic fingerprinting based on amplified fragment length polymorphism and inter simple sequence repeat markers were performed. The single spore isolates exhibited differential pathogenicity, which did not correlate with the morphological groupings or to groupings defined by molecular approaches. Moreover, 10 pathogenic isolates out of the 44 single-spored tested were positive for the host-specific AM-toxin gene based upon polymerase chain reaction amplification using specific primers for the AM-toxin gene. This suggests that the production of the AM-toxin may be involved in pathogenesis by some of the Italian isolates of A. alternata from apple. However, this research also suggests that a number of different Alternaria genotypes and morphotypes may be responsible for the apple disease in Italy and that a single taxon cannot be defined as the sole causal agent

First occurrence of strobilurin-resistant isolates of Stemphylium vesicarium in an Italian pear orchard

Stemphylium vesicarium (Wallr) Simm. is the causal agent of brown spot, the main fungal disease of pear in Italy (Po valley) since the late 1970s, but it is also present in other European countries such as Spain, France, The Netherlands, Portugal and Belgium. Many fungicides (mainly dithiocarbamates and dicarboximides) have been applied in field to control it. From the late 1990s new products have been introduced and among them the strobilurins kresoxim-methyl (1998), trifloxystrobin (2002) and more recently pyraclostrobin+boscalid (2006). Till 2005 S. vesicarium sensitivity to strobilurin fungicides have not shown any shift (MIC<0.5 mg/l) from baseline values both for kresoxim-methyl and trifloxystrobin according to a good efficacy in field. During the season 2006, the first strobilurin-resistant isolates of Stemphylium vesicarium were detected in a commercial pear orchard in north-eastern Italy (Emilia-Romagna region) where a heavy control failure was observed. In vitro sensitivity tests on conidial germination were carried out on this population with the 3 strobilurins. The concentrations used were 0.5 and 2 mg a.i./l and the evaluations were made after 3, 5 and 24 hours after inoculation. Already after 3 hours of incubation the population showed germination greater than 74% referred to untreated control at both the concentrations tested and towards all strobilurins. Another sensitivity test on conidial germination was carried out using the formulated compounds Stroby (kresoxim-methyl, BASF) and Flint (trifloxystrobin, Bayer) at 2, 10 and 100 mg a.i./l. Also in this case after 3 hours of incubation the germination of the population was greater than 90% of the untreated control. Finally the mitochondrial DNA of the isolates was analysed. After DNA extraction PCR was performed to amplify a gene fragment codifying for the region containing the G143A mutation. The presence of this mutation was then confirmed. In conclusion both in vitro test and genetic analysis showed that these isolates of S. vesicarium were resistant to all strobilurin fungicides tested. This is the first time where a failure in pear brown spot control in field is demonstrated to be caused by the occurrence of resistant isolates

EVOLUZIONE DELLA SENSIBILITÀ DI STEMPHYLIUM VESICARIUM, AGENTE DELLA MACULATURA BRUNA DEL PERO AI FUNGICIDI IN ITALIA

Riassunto E’ stata osservata una diffusa resistenza di Stemphylium vesicarium ai dicarbossimidici e la sua regressione, in seguito all’interruzione dei trattamenti, in tempi variabili a seconda della frequenza di individui resistenti selezionati nel frutteto. Si è riscontrata una resistenza incrociata del patogeno tra dicarbossimidici e fludioxonil, presente però solo in un fenotipo raro e che pertanto non costituisce un reale problema in campo. La sensibilità di S. vesicarium agli analoghi delle strobilurine, dopo circa dieci anni dalla loro introduzione in campo, non ha subito modifiche sostanziali, anche se sono stati recentemente riscontrati sporadici isolati resistenti. I noti ditiocarbammati e il recente boscalid non hanno evidenziato variazioni di sensibilità. Evolution in Italy of the sensitivity to fungicides in Stemphylium vesicarium, the causal agent of pear brown spot Abstract The control of Stemphylium vesicarium, the causal agent of pear brown spot, needs many treatments from petal fall to fruit ripening, therefore a knowledge of the effectiveness of fungicides is important. After the occurrence of the first problems in pear brown spot control in the early 1990s with procymidone, in vitro studies have demonstrated the occurrence of pathogen resistance in Italy. Further studies identified four phenotypes of S. vesicarium with different degrees of sensitivity to dicarboximides: the sensitive (S), the S+ slightly resistant to procymidone and iprodione, the R1 highly resistant to procymidone and moderately resistant to the other dicarboximides and the R2 highly resistant to all dicarboximides. These phenotypes are spread in all pear growing areas of Po valley. Fortunately the sensitive phenotype is still the most frequent followed by the R1 phenotype. The other resistant phenotypes are very rarely found in the field. Another important aspect considered was the possibility of the resistance to regress. The frequency of the phenotypes inside the populations of each orchard influences the time of resistance regression. If the resistant frequency is high more years of interruption of treatments are needed. The cross resistance between dicarboximides and phenylpyrroles was observed only in R2 phenotype, therefore it does not represent a real problem in the field because of their rarity. A wide monitoring was carried out also to evaluate the sensitivity of S. vesicarium to strobilurins. Ten years after their introduction in the field, they are still active and with EC50 values comparable to baseline ones, albeit the first few resistant isolates have been found since 2006. Only one of these cases was linked to a failure of strobilurins in pear brown spot control and it has appeared after several years of intense use of these compounds. Nevertheless this is an interesting information, because it demonstrates that S. vesicarium is able to develop strobilurin resistance and therefore it underlines again the importance of following strictly anti-resistance strategies. No changes in sensitivity were noted in S. vesicarium to dithiocarbamates, multi-site fungicides with a low resistance risk but widely used against pear brown spot since its appearance in the late 1970s. The study of S. vesicarium sensitivity to boscalid had the same result, in fact two years after its registration on pear in Italy, the level of sensitivity is comparable to that of populations collected before its introduction in the field

Baseline sensitivity of Stemphylium vesicarium, the causal agent of pear brown spot, to boscalid

INTRODUCTION The control of Stemphylium vesicarium (Wallr.) Simm., the causal agent of pear brown spot, is a true concern for pear growers in Italy because many fungicide treatments are required from petal fall to fruit ripening (Ponti et al.,1996; Brunelli et al., 2004). The occurrence of resistance to dicarboximides in the early 1990’s (Brunelli et al., 1997) and to strobilurins in 2006 (Collina et al., 2007) complicated the control of this pathogen even more. The introduction in the field of new fungi-cides with different mechanisms of action is thus fundamental in order to enlarge the range of effective fungicides against pear brown spot and to reduce the risk of further resistances. At the end of the 2006 season boscalid was registered in Italy for pear. It belongs to the carboxamide-fungicide group and inhibits the respiratory chain acting on the enzyme succinate dehydrogenase in complex II (Stammler et al., 2007). This mode of action is different from that of both dicarboximide and strobilurin fungicides and it could be used in cases of field resistance to these compounds. Nevertheless, boscalid is considered by the FRAC to have a medium risk of resistance for its spe-cific target (www.frac.info). In order to evaluate the sensitivity of S. vesicarium to this fungicide, an in vitro assay was developed comparing different methods (on mycelial growth with differ-ent media and on conidial germination). Baseline sensitivity was then determined for isolates which have never been exposed to boscalid