Truncatella angustata associated with grapevine trunk disease in northern Iran

In recent years, grapevine trunk diseases have gained growing attentions due to worldwide incidence of the disease. In a survey on fungal agents associated with grapevine trunk diseases in northern Iran, wood samples were collected from grapevines having the symptoms of declination. Isolation was made using routine plant pathology methods. A coelomycetous fungus with appendage-bearing conidia was recovered from symptomatic tissues. Based on morphological and cultural characteristics, the causal agent of the disease was identified as Truncatella angustata. The identity of the species was further confirmed by sequence data of internal transcribed spacer-rDNA region. A phylogeny inferred using sequence data obtained in this study, together with the sequences from GenBank, clustered our isolates together with T. angustata known from other host plant species. Pathogenicity tests performed on detached shoots of grapevines led to the same symptoms as observed in field conditions. This is first study on the pathogenicity of T. angustata on grapevine in Iran and first report on the occurrence of T. angustata on grapevine in Iran.     

Microsporum fulvum, an Ignored Pathogenic Dermatophyte: A New Clinical Isolation from Iran

Misidentifying with Microsporum gypseum has for a long time been accounted for less prevalence of the geophilic species, Microsporum fulvum in human dermatophytosis. We describe a new case of infection with the species in an Iranian young man. Direct examination of skin scrapings revealed a tinea corporis, and morphological study of the recovered isolate from the culture resulted in the identification of M. gypseum. However, PCR amplification of ITS1-5.8S rDNA-ITS2 region and subsequent ITS-RFLP and sequencing were indicative of M. fulvum as the true causative agent. To recognize M. fulvum in human infections and to validate the morphologically distinguished isolates of M. gypseum, the genetic-based identification is strongly recommended.     

Probing the interaction of silver nanoparticles with tau protein and neuroblastoma cell line as nervous system models

Interestingly pharmaceutical sciences are using nanoparticles (NPs) to design and develop nanomaterials-based drugs. However, up to recently, it has not been well realized that NPs themselves may impose risks to the biological systems. In this study, the interaction of silver nanoparticles (AgNPs) with tau protein and SH-SY5Y neuroblastoma cell line, as potential nervous system models, was examined with a range of techniques including intrinsic fluorescence spectroscopy, circular dichroism (CD) spectroscopy, 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and acridine orange/ethidium bromide (AO/EB) dual staining method. Fluorescence study showed that AgNPs with a diameter of around 10–20 nm spontaneously form a static complex with tau protein via hydrogen bonds and van der Waals interactions. CD experiment revealed that AgNPs did not change the random coil structure of tau protein. Moreover, AgNPs showed to induce SH-SY5Y neuroblastoma cell mortality through fragmentation of DNA which is a key feature of apoptosis. In conclusion, AgNPs may induce slight changes on the tau protein structure. Also, the concentration of AgNPs is the main factor which influences their cytotoxicity. Since, all adverse effects of NPs are not well detected, so probably additional more specific testing would be needed.     

Effet du climat et de l’exposition sur la dynamique des populations de la cochenille violette,Parlatoria oleae Colvée (Hemiptera : Diaspididae), en conditions arides

Résumé

Ce travail a pour objectif l’étude de quelques aspects bio-écologiques de la cochenille violette, Parlatoria oleae Colvée 1880, bio-agresseur des cultures de l’Olivier en régions arides. Le suivi du cycle biologique ainsi que la démo-écologie de ce ravageur ont été réalisés grâce à des dénombrements périodiques des populations sur les différents organes de l’arbre (méthodes de Vasseur &; Schvester) de décembre 2010 à décembre 2011 dans la région d’Ain Touta (nord-est algérien). L’espèce y a montré deux générations par an : une génération printanière se développant entre avril et juillet et une génération automnale évoluant entre août et octobre. La ponte débuta en avril et s’échelonna jusqu‘à la fin septembre. L’exposition nord est la plus favorable à cette diaspine qui y trouve des conditions microclimatiques optimales pour son développement. La ponte moyenne est de 8 à 9 ?ufs par femelle. L’analyse statistique de l’effet des conditions climatiques étudiées (températures minimale, maximale et moyenne ; précipitations, gelée et indice d’aridité De Martone) sur les effectifs des différents stades, montre une grande variabilité d’un stade à un autre. L’analyse statistique établie révèle également que les effectifs de l’espèce présentent des variations très hautement significatives selon l’orientation dans l’arbre d’olive colonisé.     

Measurement of some Benzylisoquinoline Alkaloids in Different Organs of Persian Poppy during Ontogenetical Stages

Papaver bracteatum, a perennial species, has been known as a rich source of thebaine and a potential alternative to Papaver somniferum for the production of codeine and some semisynthetic antagonist drugs. In this study, ion mobility spectrum (IMS) of the root, leaf, bottom part of stem, upper part of stem, capsule wall, petal, and capsule content during developmental stages of P. bracteatum including annual rosette, perennial rosette, bud initiation, pendulous bud, preflowering, and lancing were investigated. The IMS revealed thebaine, papaverine, and noscapine as the major components of the extracted alkaloids. Based on the results of the study it appears that, at least in part, there is a competition among the biosynthesis pathways of papaverine, noscapine, and morphinan alkaloids from a common source . Root and capsule wall were the most potent organs for extraction of thebaine, while lancing stage was the best developmental stage for thebaine exploitation. However, it seems that total biomass of root and capsule wall plays a key role in the final selection of favorite organ. Although papaverine and noscapine in the stem at preflowering stage had the most quantity, significant amounts were found in the capsule wall. In general, total alkaloid content of leaf was lower than the other plant parts.