Modulation of defense genes and phenolic compounds in wild blueberry in response to Botrytis cinerea under field conditions.

Botrytis blight is an important disease of wild blueberry [(Vaccinium angustifolium (Va) and V. myrtilloides (Vm))] with variable symptoms in the field due to differences in susceptibility among blueberry phenotypes. Representative blueberry plants of varying phenotypes were inoculated with spores of B. cinerea. The relative expression of pathogenesis-related genes (PR3, PR4), flavonoid biosynthesis genes, and estimation of the concentration of ten phenolic compounds between uninoculated and inoculated samples at different time points were analyzed. Representative plants of six phenotypes (brown stem Va, green stem Va, Va f. nigrum, tall, medium, and short stems of Vm) were collected and studied using qRT-PCR. The expression of targeted genes indicated a response of inoculated plants to B. cinerea at either 12, 24, 48 or 96 h post inoculation (hpi). The maximum expression of PR3 occurred at 24 hpi in all the phenotypes except Va f. nigrum and tall stem Vm. Maximum expression of both PR genes occurred at 12 hpi in Va f. nigrum. Chalcone synthase, flavonol synthase and anthocyanin synthase were suppressed at 12 hpi followed by an upregulation at 24 hpi. The expression of flavonoid pathway genes was phenotype-specific with their regulation patterns showing temporal differences among the phenotypes. Phenolic compound accumulation was temporally regulated at different post-inoculation time points. M-coumaric acid and kaempferol-3-glucoside are the compounds that were increased with B. cinerea inoculation. Results from this study suggest that the expression of PR and flavonoid genes, and the accumulation of phenolic compounds associated with B. cinerea infection could be phenotype specific. This study may provide a starting point for understanding and determining the mechanisms governing the wild blueberry-B. cinerea pathosystem.

Elucidation of the molecular responses during the primary infection of wild blueberry phenotypes with Monilinia vaccinii-corymbosi under field conditions.

BACKGROUND: Monilinia blight caused by Monilinia vaccinii-corymbosi (Reade) Honey (M.vc) is a major disease of wild blueberry that can result in severe crop losses in the absence of an integrated disease management programme. The fungus causes blight in the emerging floral and vegetative buds, but the degree of susceptibility varies among the different wild blueberry phenotypes, ranging from the highly susceptible V. a. f. nigrum to the moderately susceptible V. angustifolium and the least susceptible V. myrtilloides. RESULTS: The present study evaluated the defense responses of these major phenotypes during their primary infection (floral buds) with M.vc. The temporal expression profiles of PR genes (PR3 and PR4) and the flavonoid pathway structural genes (CHS, ANS, ANR, DFR and FLS) were analysed. The PR3 and PR4 gene expression profiles revealed that V. myrtilloides responded to M.vc infection by activating the expression of both PR genes. V. a. f. nigrum, on the other hand, failed to activate these genes, while V. angustifolium, exhibited an intermediate response. Our study with the flavonoid pathway genes indicated variability in activation of the genes during post-infection time points with ANS and ANR in V. myrtilloides, FLS in V. angustifolium and no response observed in V. a. f. nigrum. CONCLUSIONS: Altogether, this study highlights that the degree of phenotype susceptibility is associated with the timely activation of host defense responsive genes. Data obtained in this study provided a starting point for a better understanding of the wild blueberry- M. vaccinii-corymbosi pathosystem.

Idiopathic Gingival Fibromatosis in a Pediatric Patient.

Idiopathic gingival fibromatosis (IGF) is a rare, benign, slow-growing proliferation of the gingival tissues involving both maxillary and mandibular gingiva. It is exacerbated during the eruptive phase of both primary and permanent dentitions. The purpose of this article is to report the case of a 10-year-old boy who presented with IGF whose gingival enlargement covered the occlusal surfaces of many teeth and displaced the erupting dentition, compromising the patient's cosmetics, function, speech and development. The treatment involved gingivectomy and gingivoplasty, combining both surgical and laser methods. The case showed remarkable esthetic and functional im provement, without signs of recurrence one year post-treatment.

Selection and validation of reliable reference genes for gene expression studies from Monilinia vaccinii-corymbosi infected wild blueberry phenotypes.

Monilinia blight disease caused by Monilinia vaccinii-corymbosi (Reade) Honey (M.vc) causes severe damage and economic losses in wild blueberry growing regions. Molecular mechanisms regulating defence responses of wild blueberry phenotypes towards this causal fungus are not yet fully known. A reliable quantification of gene expression using quantitative real time PCR (qPCR) is fundamental for measuring changes in target gene expression. A crucial aspect of accurate normalisation is the choice of appropriate reference genes. This study evaluated the expression stability of seven candidate reference genes (GAPDH, UBC9, UBC28, TIP41, CaCSa, PPR and RH8) in floral tissues of diploid and tetraploid wild blueberry phenotypes challenged with M.vc. The expression stability was calculated using five algorithms: geNorm, NormFinder, BestKeeper, deltaCt and RefFinder. The results indicated that UBC9 and GAPDH were the most stable reference genes, while RH8 and PPR were the least stable ones. To further validate the suitability of the analyzed reference genes, the expression level of a pathogenesis related protein gene (i.e., PR3) was analysed for both phenotypes at four time points of infection. Our results may be beneficial for future studies involving the quantification of relative gene expression levels in wild blueberry species.

Effects of different dentinal drying methods on the adhesion of glass ionomer restorations to primary teeth.

BACKGROUND: Glass ionomer cements that form an inevitable part of pediatric restorative dentistry are inherently sensitive to moisture. The influence of different drying techniques on the shear bond strength of glass ionomer cements to primary teeth dentin has not been established. AIMS: The purpose of the study was to evaluate the effects of different drying methods for different drying time periods on the shear bond strength of GC Fuji IX to primary tooth dentine. SUBJECTS AND METHODS: A total of 135 caries-free primary teeth were selected and ground to a flat dentinal surface. Specimens were randomly divided into three groups - air dry, blot dry, and suction dry of 45 specimens each. Of these, 15 specimens each were dried for 2 s, 5 s, and 10 s. GC Fuji IX was condensed into Teflon molds, and the specimens were subjected to shear bond strength testing. RESULTS: The mean shear bond strength values for the different time intervals were analyzed with analysis of variance test. In the air-dry group, the maximum shear bond strength values were obtained when the specimens were dried for 5 s and the least when dried for 2 s (P = 0.00). In the blot-dry and suction-dry groups, the highest values were obtained when the specimens were dried for 10 s and least for 2 s (P = 0.039 and 0.000, respectively). CONCLUSIONS: Among the three drying methods employed in the study, the maximum shear bond strength of the glass ionomer restoration was observed in the air-dry group.

Blandin and Nuhn mucocele in a pediatric patient.

Oral mucoceles are benign lesions that may appear in any location on the mucosal surfaces of the oral cavity where underlying minor salivary glands are found. The lower lip is the most frequently affected and the most widely reported location. Mucoceles involving the glands of Blandin and Nuhn are infrequent and constitute only about 1.9%-10.3% of the reported cases. Superficial mucoceles are a rare subtype of the Blandin and Nuhn mucoceles and are found only in 4.3%-10% of the mucocele excisions. The purpose of this report is to present a case of a superficial mucocele in the ventral surface of the tongue in a 7-year-old child. The lesion was treated with excisional biopsy.

Traumatic sublingual ulceration in a newborn

Natal and neonatal teeth are those which are present in the oral cavity at the time of birth and within thirty days of birth. They are likely to be associated with traumatic sublingual ulceration caused to the suckling as well as movements of the tongue. The treatment of choice is mostly conservative whenever possible. The purpose of this report is to present a case of traumatic sublingual ulceration in a twenty days old baby. The lesion resolved soon after the offending tooth was removed.