A leaf spot and blight of greenhouse tomato seedlings incited by a Herbaspirillum sp.

A leaf spot and blighting were observed on leaves of tomato transplants from a producer in Florida in 2001 and 2002. A nonfluorescent bacterium was isolated consistently from affected tissue. The typical bacterium was a gram negative, strictly aerobic, slightly curved rod with one or two flagella. Sequence analysis of the 16S rRNA indicated that two representative strains, F1 and SE1, had greater than 99% nucleotide sequence identity with Herbaspirillum huttiense and H. rubrisubalbicans. The cellular fatty acid composition of the total of 16 tomato strains was very similar to H. huttiense and H. rubrisubalbicans. Based on carbon utilization, six of nine strains tested with the Biolog system were identified as Herbaspirillum spp. The tomato strains were oxidase positive and grew at 40 degrees C, but were negative for levan production, pectate hydrolysis, and arginine dihydrolase activity. Based upon this polyphasic analysis, we concluded that the strains were most closely related to H. huttiense, although placement in this species would require further analyses. However, the tomato strains and H. rubrisubalbicans, but not H. huttiense, caused confluent necrosis when infiltrated at high concentrations into tomato leaves and were able to produce leaf spot symptoms on inoculated tomato seedlings in the greenhouse. Using pulsed-field gel electrophoresis, we determined that there was considerable variability between the strains collected in 2001 and 2002

Deficits in attention to emotional stimuli distinguish youth with severe mood dysregulation from youth with bipolar disorder.

Studying attention in the context of emotional stimuli may aid in differentiating pediatric bipolar disorder (BD) from severe mood dysregulation (SMD). SMD is characterized by chronic irritability, arousal, and hyper-reactivity; SMD youth frequently receive a BD diagnosis although they do not meet DSM-IV criteria for BD because they lack manic episodes. We compared 57 BD (14.4 +/- 2.9 years old, 56% male), 41 SMD (12.6 +/- 2.6 years old, 66% male), and 33 control subjects (13.7 +/- 2.5 years old, 52% male) using the Emotional Interrupt task, which examines how attention is impacted by positive, negative, or neutral distracters. We compared reaction time (RT) and accuracy and calculated attention interference scores by subtracting performance on neutral trials from emotional trials. Between-group analyses indicated that SMD subjects had significantly reduced attention interference from emotional distracters relative to BD and control subjects. Thus, attention in SMD youth was not modulated by emotional stimuli. This blunted response in SMD youth may contribute to their affective and behavioral dysregulation

Reclassification of Subspecies of \u3ci\u3eAcidovorax avenae\u3c/i\u3e as \u3ci\u3eA. Avenae\u3c/i\u3e (Manns 1905) emend., \u3ci\u3eA. cattleyae \u3c/i\u3e (Pavarino, 1911)comb.nov., \u3ci\u3eA. citrulli\u3c/i\u3e Schaad et al.,1978)comb.nov., and proposal of \u3ci\u3eA. oryzae \u3c/i\u3esp. nov.

The bacterium Acidovorax avenae causes disease in a wide range of economically important monocotyledonous and dicotyledonous plants, including corn, rice, watermelon, anthurium, and orchids.Genotypic and phenotypic relatedness among strains of phytopathogenic A. avenae sub sp. avenae, A. avenae sub sp. citrulli, A. avenae subsp. cattleyae and A. konjaci, as well as all other Acidovorax species, including A. facilis, the type strain of Acidovorax, was determined.The16s rDNA sequencing confirmed previous studies showing the environmental species to be very distant from the phytopathogenic species. DNA/DNA reassociation assays on the different strains of A. avenae revealed four(A, B, C, and D) distinct genotypes. Taxon A included six A. avenae subsp. avenaestrains from corn that had a mean reciprocal similarity of 81%; taxon B included six A. avenae sub sp. avenae strains from rice that had a mean reciprocal similarity of 97%; taxon C contained 11 A. avenae sub sp. citrulli strains from cucurbits (cantaloupe, watermelon, and pumpkin) that had a mean reciprocal similarity of 88%, and taxon D contained four A. avenae sub sp. cattleyae strains from orchids that had a mean similarity of 98%

Neural circuitry engaged during unsuccessful motor inhibition in pediatric bipolar disorder

Objective: Deficits in motor inhibition may contribute to impulsivity and irritability in children with bipolar disorder (BPD). Therefore, studies of the neural circuitry engaged during failed motor inhibition in pediatric BPD may contribute to our understanding of the pathophysiology of the illness. We tested the hypothesis that children with BPD and controls would differ in ventral prefrontal cortex (vPFC), striatal, and anterior cingulate activation during unsuccessful motor inhibition. We also compared activation in medicated vs. unmedicated children with BPD, and in children with BPD and ADHD (BPD+ADHD) vs. those with BPD but without ADHD (BPD-ADHD). Method: Event-related fMRI study comparing neural activation in children with BPD and controls while they performed a motor inhibition task. The sample included 26 children with BPD (13 unmedicated, 15 with ADHD) and 17 age, gender, and IQ matched controls. Results: On failed inhibitory trials, controls showed greater bilateral striatal and right vPFC activation than did patients. While our findings were somewhat more prominent in unmedicated than medicated, patients, and in BPD+ADHD than BPD-ADHD, the findings did not differ significantly (?) among these subgroups of children with BPD. Conclusions: Compared to controls, children with BPD may have deficits in their ability to engage striatal structures and right vPFC during unsuccessful inhibition. (this reads confusingly to me—they’re deficient in their capacity to engage structures when they’re behaviorally unsuccessful? Perhaps reword?) Further research is needed to determine whether these deficits play a role in the emotional and behavioral dysregulation characteristic of BPD

Pediatric Bipolar Disorder Versus Severe Mood Dysregulation: Risk for Manic Episodes on Follow-Up

OBJECTIVE: An important question in pediatric bipolar research is whether marked nonepisodic irritability is a manifestation of bipolar disorder in youth. This study tests the hypothesis that youth with severe mood dysregulation (SMD), a category created for the purpose of studying children presenting with severe nonepisodic irritability, will be significantly less likely to develop (hypo-)manic or mixed episodes over time than will youth with bipolar disorder (BD). METHOD: Patients with SMD (N = 84) and narrowly defined BD (N = 93) at baseline were followed up in 6-monthly intervals using the relevant K-SADS modules to ascertain (hypo-)manic or mixed episodes. RESULTS: Only one of 84 SMD subjects (1/84 [1.2%]; 95% confidence interval CI = 0.0003 to 0.064) experienced a (hypo-)manic or mixed episode during the study (median follow-up = 28.7 months). The frequency of such episodes was more than 50 times higher in those with narrowly defined BD (58/93 [62.4%]; 95% CI 0.52 to 0.72). CONCLUSIONS: These data suggest that, over an approximately 2-year follow-up period, youth with SMD are unlikely to develop (hypo-)manic or mixed episodes

Irritability in youth: A critical integrative review

Irritability, defined as proneness to anger that may reach an impairing extent, is common in youth. There has been a recent upsurge in relevant research. We combine systematic and narrative review approaches to integrate the latest clinical and translational findings and provide suggestions to address research gaps. Clinicians and researchers should assess irritability routinely; specific assessment tools are now available. Informant effects are prominent, stable, and vary by age and gender. The prevalence of irritability is particularly high in attention deficit hyperactivity disorder, autism spectrum disorder, and mood and anxiety disorders. Irritability is associated with impairment and suicidality risk independent of co-occurring diagnoses. Irritability trajectories have been identified that are differentially associated with clinical outcomes; some begin early in life. Youth irritability is associated with increased risk later in life for anxiety, depression, behavioral problems, and suicidality. Irritability is moderately heritable and genetic associations differ based on age and comorbid illnesses. Parent management training is effective for constructs related to irritability, but its efficacy in irritability should be tested rigorously, as should novel mechanism-informed interventions (e.g., those targeted to frustration exposure). Associations between irritability and suicidality and the impact of cultural context are important, under-researched topics. Large, diverse, longitudinal samples that extend into adulthood are needed. Data from both animal and human research indicate that aberrant responses to frustration and threat are central to the pathophysiology of irritability, thus affording important translational opportunities