Tomato apical stunt viroid (TASVd) was initially discovered in the Ivory Coast (2). It was later reported in Indonesia and more recently was found to be responsible for severe outbreaks in protected tomatoes in Israel (1) and Tunisia (3). Although not of quarantine status, TASVd is included in the EPPO alert list. In 2005, severe arrest of apical growth and leaf chlorosis were observed in tomato samples from northern Sénégal. Tomato yellow leaf curl virus was initially identified in some samples, but since the symptoms observed were reminiscent of those associated with viroid infection, samples were analyzed by return-polyacrylamide gel electrophoresis and molecular hybridization with a Potato spindle tuber viroid (PSTVd) probe. Positive results prompted a reanalysis by reverse transcription-PCR assays specific for PSTVd or TASVd. Positive amplification was only obtained with the TASVd-specific primers (Vir+ GGGGAAACCTGGAGGAA and Vir- GGGGATCCCTGAAGGAC), and the identity of the viroid confirmed by sequencing of the amplified fragment. The complete genome sequence obtained (GenBank Accession No. EF051631) shows 94 to 96% identity with other TASVd sequences in the databases, the highest homology being with the original Ivory Coast isolate (96%, 11 mutations, and 4 indels for the 362-nt genome). These results provide new information on the diversity of TASVd and of its detrimental potential for tomato crops and represent, to our knowledge, the first report of the presence of TASVd in Sénégal. References: (1) Y. Antignus et al. Phytoparasitica 30:502, 2002. (2) C. R. Walter. Acad. Sci. 292:537, 1981. (3) J. Th. J. Verhoeven et al. Plant Disease 90:528, 2006.
During the COVID-19 pandemic, people across the globe have been exposed to large amounts of statistical data. Previous studies have shown that individuals' mathematical understanding of health-related information affects their attitudes and behaviours. Here, we investigate the relation between (i) basic numeracy, (ii) COVID-19 health numeracy, and (iii) COVID-19 health-related attitudes and behaviours. An online survey measuring these three variables was distributed in Canada, the United States (US) and the United Kingdom (UK) (
n
= 2032). In line with predictions, basic numeracy was positively related to COVID-19 health numeracy. However, predictions, neither basic numeracy nor COVID-19 health numeracy was related to COVID-19 health-related attitudes and behaviours (e.g. follow experts’ recommendations on social distancing, wearing masks etc.). Multi-group analysis was used to investigate mean differences and differences in the strength of the correlation across countries. Results indicate there were no between-country differences in the correlations between the main constructs but there were between-country differences in latent means. Overall, results suggest that while basic numeracy is related to one's understanding of data about COVID-19, better numeracy alone is not enough to influence a population's health-related attitudes about disease severity and to increase the likelihood of following public health advice.
Silver-Russell syndrome (SRS) is a rare imprinting disorder characterized by prenatal and postnatal growth retardation. The two principal causes of SRS are loss of methylation on chromosome 11p15 (11p15 LOM) and maternal uniparental disomy of chromosome 7 (UPD(7)mat). Knowledge of the neuropsychological profile of SRS remains sparse and incomplete even if several difficulties related to attention and learning have been reported both in the literature and by patients with SRS. These difficulties could be the result of troubles in different cognitive domains, but also of executive dysfunction. Nevertheless, executive functioning has never been investigated, even though executive functions play an essential role in psychological development, and are extensively involved in daily life. The present study explored the executive functioning of individuals with SRS due to UPD(7)mat or 11p15 LOM. A battery of executive tasks assessing cognitive flexibility, inhibitory control, and working memory, together with a task assessing sustained attention, was administered to 19 individuals with SRS (13–39 years) and 19 healthy controls. The Behavior Rating Inventory of Executive Function was also completed by the participants’ families. The results showed that participants with SRS had similar performance (z-scores) to our controls, in a context of normal intellectual efficiency. Group comparisons with Bayesian statistics showed a single difference between the 11p15 LOM and control groups: the completion time for part A of the Trail Making Test appeared to be longer in the 11p15 LOM group than in the control group. However, at the clinical level, several participants with SRS had clinically significant scores on various measures of EFs. Thus, the cognitive phenotype of SRS did not appear to be characterized by executive dysfunction, but individuals with SRS could be at high risk of developing executive dysfunction or attention-deficit/hyperactivity disorder. These results provide new insights into the neuropsychological profile of individuals with SRS.
La maladie des tubercules fusiformes de la pomme de terre est due au Potato spindle tuber viroid (PSTVd), microorganisme qui ne peut être détecté par des méthodes sérologiques classiques. En France, le Laboratoire National de la Protection des Végétaux (Station de Quarantaine Pomme de Terre) a débuté les tests de détection du viroïde avec une méthode « reverse-PAGE», ne nécessitant pas de réactif spécifique mais peu adaptée aux grandes séries d'analyses. Il a ensuite maîtrisé une technique d'hybridation moléculaire qui, associée à une technique d'extraction permettant de travailler de grandes séries d'échantillons frais ou lyophilisés en flux continu, supporte la comparaison avec une technique RT-PCR encore en phase de validation. Malgré la relative lourdeur de la technique d'hybridation moléculaire (comparée aux techniques sérologiques classiques), la méthode a pu être transférée dans deux laboratoires partenaires qui réalisent une partie des tests des programmes officiels français de surveillance, confirmant la fiabilité et la robustesse de la méthode mise au point.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.