Publications by authors named "Venkatesh Balakrishnan"

Aim: The aim of this study is to compare the canal cleaning ability of S-One file (AF BLUE) system with WaveOne Gold single file system, using scanning electron microscopy (SEM).

Materials And Methods: In the present study, 40 freshly extracted permanent mandibular premolars with a single-root canal and straight roots were selected. The teeth were randomly divided into three groups.

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Aim: The aim of this in vivo study was to evaluate the revascularization procedure both in immature and mature teeth with necrotic pulp and open apices, disinfected with triple antibiotic paste followed by inducing blood clot in the root canal.

Materials And Methods: Fifteen patients were selected who presented with immature and mature permanent teeth with pulpal necrosis and open apices. In the first visit, the root canal was accessed with LA and rubber dam isolation; then the canal was disinfected using triple antibiotic paste containing ciprofloxacin, metronidazole, and clindamycin in the ratio of 1:1:1 and closed with IRM.

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Background: The yersiniae (Enterobacteriaceae) occupy a variety of niches, including some in human and flea hosts. Metabolic adaptations of the yersiniae, which contribute to their success in these specialized environments, remain largely unknown. We report results of an investigation of the transcriptome under aerobic and anaerobic conditions for Y.

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Plants have evolved efficient defense mechanisms known as priming and synergy, both of which can mobilize defense responses more extensively against successive pathogen invasion or simultaneous stimulation by different signal molecules. However, the mechanisms underlying these phenomena were largely unknown. In the present study, we used cultured rice cells and combination of purified MAMP molecules as a model system to study the mechanisms of these phenomena.

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Background: Dickeya dadantii and Pectobacterium atrosepticum are phytopathogenic enterobacteria capable of facultative anaerobic growth in a wide range of O2 concentrations found in plant and natural environments. The transcriptional response to O2 remains under-explored for these and other phytopathogenic enterobacteria although it has been well characterized for animal-associated genera including Escherichia coli and Salmonella enterica. Knowledge of the extent of conservation of the transcriptional response across orthologous genes in more distantly related species is useful to identify rates and patterns of regulon evolution.

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We present results of the first comprehensive proteomic analysis of the outer membrane of the bacterial phytopathogen Dickeya dadantii strain 3937 and its response to virulence-contributing factors such as host plant extract, acidic stress, and iron starvation. We analyzed the carbonate-insoluble membrane fractions, which are highly enriched for outer membrane proteins, using two-dimensional electrophoresis and identified the proteins by MALDI-TOF MS. Forty unique proteins were identified, some of which were differentially expressed under the above conditions.

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PAMP (pathogen-associated molecular pattern) recognition plays an important role during the innate immune response in both plants and animals. Lipopolysaccharides (LPS) derived from Gram-negative bacteria are representative of typical PAMP molecules and have been reported to induce defense-related responses, including the suppression of the hypersensitive response, the expression of defense genes and systemic resistance in plants. However, the details regarding the precise molecular mechanisms underlying these cellular responses, such as the molecular machinery involved in the perception and transduction of LPS molecules, remain largely unknown.

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The PhoPQ two-component system regulates virulence factors in Erwinia chrysanthemi, a pectinolytic enterobacterium that causes soft rot in several plant species. We characterized the effect of a mutation in phoQ, the gene encoding the sensor kinase PhoQ of the PhoPQ two-component regulatory system, on the global transcriptional profile of E. chrysanthemi using cDNA microarrays and further confirmed our results by quantitative reverse transcription-PCR analysis.

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Background: Gene expression studies on non-model organisms require open-end strategies for transcription profiling. Gel-based analysis of cDNA fragments allows to detect alterations in gene expression for genes which have neither been sequenced yet nor are available in cDNA libraries. Commonly used protocols for gel-based transcript profiling are cDNA differential display (DDRT-PCR) and cDNA-AFLP.

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