When guard cell protoplasts (GCPs) of tree tobacco [Nicotiana glauca (Graham)] are cultured at 32°C with an auxin (1-napthaleneacetic acid) and a cytokinin (6-benzylaminopurine), they reenter the cell cycle, dedifferentiate, and divide. GCPs cultured similarly but at 38°C and with 0.1 m Ϯ -cis,trans-abscisic acid (ABA) remain differentiated. GCPs cultured at 38°C without ABA dedifferentiate partially but do not divide. Cell survival after 1 week is 70% to 80% under all of these conditions. In this study, we show that GCPs cultured for 12 to 24 h at 38°C accumulate heat shock protein 70 and develop a thermotolerance that, upon transfer of cells to 32°C, enhances cell survival but inhibits cell cycle reentry, dedifferentiation, and division. GCPs dedifferentiating at 32°C require both 1-napthaleneacetic acid and 6-benzylaminopurine to survive, but thermotolerant GCPs cultured at 38°C Ϯ ABA do not require either hormone for survival. Pulse-labeling experiments using 5-bromo-2-deoxyuridine indicate that culture at 38°C Ϯ ABA prevents dedifferentiation of GCPs by blocking cell cycle reentry at G1/S. Cell cycle reentry at 32°C is accompanied by loss of a 41-kD polypeptide that cross-reacts with antibodies to rat (Rattus norvegicus) extracellular signal-regulated kinase 1; thermotolerant GCPs retain this polypeptide. A number of polypeptides unique to thermotolerant cells have been uncovered by Boolean analysis of two-dimensional gels and are targets for further analysis. GCPs of tree tobacco can be isolated in sufficient numbers and with the purity required to study plant cell thermotolerance and its relationship to plant cell survival, growth, dedifferentiation, and division in vitro.At high temperatures, some plant species develop a thermotolerance that enables them to survive until cooler temperatures return (for review, see Francis and Barlow, 1988). Little is known about the molecular mechanisms by which high temperature alters the growth of thermotolerant plants, nor are the signal transduction pathways that activate plant thermotolerance understood. A few studies with meristems and seeds indicate that sublethal high temperatures (30°C-35°C) affect cell cycle progression, lengthening the cycle or certain of its phases in some tissues, but shortening them in others (Francis and Barlow, 1988). Both heat shock proteins (Hsps) and mitogen-activated protein kinases (MAPKs or extracellular signal-regulated kinases [ERKs]) have been implicated in development of thermotolerance. Arabidopsis plants underexpressing Hsp 101 have a diminished capacity to develop thermotolerance, whereas those overexpressing this protein have an enhanced capacity to survive abrupt shifts to extreme high temperatures (Queitsch et al., 2000). Evidence for the involvement of MAPK in thermotolerance comes mainly from studies with yeast (Saccharomyces cerevisiae; Trotter et al., 2001). Still, we do not know how these proteins and others with which they interact signal the development of plant thermotolerance and thereby affect cell survival, gr...

Objective: Children and adolescents with restless legs syndrome (RLS) are commonly diagnosed with comorbid attention defi cit hyperactivity disorder and behavioral disturbances. Uncertainty exists over the signifi cance of other co-occurring psychiatric disorders and their pharmacologic management in children with RLS. The purpose of this study was to determine the prevalence and nature of psychiatric disorders in children with RLS and to describe the use of psychotropic medications in our study cohort. Methods:The electronic medical records of children younger than 18 years of age who had been diagnosed with RLS between January 1, 2003, and December 31, 2009, were reviewed. Only those patients whose fi ndings were consistent with the 2003 NIH workshop diagnostic criteria for probable or defi nite restless legs syndrome were included in this study. The medical records were cross-referenced for encounters with a child psychiatrist or psychologist. Likewise, only psychiatric diagnoses whose medical records explicitly refl ected DSM-IV diagnostic criteria for psychiatric disorder(s) were included. Demographic data, serum ferritin, psychotropic medications, and in some cases, the results of pharmacogenomic testing were included in the data analysis in an ad hoc fashion. Results: We found 374/922 patients who met diagnostic criteria for childhood onset RLS. The mean age of the subjects was 10.6 years (range 0 to 18) and the male to female ratio was approximately 1:1. Overall, 239/374 (64%) patients with RLS had one or more comorbid psychiatric disorders. Attention defi cit hyperactivity disorder was found in 94/374 (25%) patients, mood disturbances were found in 109/374 (29.1%) patients, anxiety disorders in 43/374 (11.5%) patients, and behavioral disturbances in 40/374 (10.9%) patients. Attention defi cit hyperactivity disorder and disruptive behavior disorders were more common in males (OR = 1.94 for both), whereas mood disturbances and anxiety disorders were more common in females (OR = 1.6 and 1.26, respectively). Mean serum ferritin levels derived from all patients without any psychiatric disorder were compared to all patients with one or more psychiatric disorder. No differences were found. The number of new psychotropic medication trials increased significantly with increase in patient age. Stimulants and antidepressant medications were the most commonly prescribed agents. As a part of clinical care, 15 of these patients underwent pharmacogenomic testing. Metabolic abnormalities were predicted by genotyping in 12/15 (80%) patients. Conclusion: Comorbid psychiatric conditions occurred in twothirds of children with RLS, underscoring the need for multidisciplinary management of this condition. An important relationship might exist between psychotropic medication, and possibly pharmacogenomic factors, in children and adolescents with symptoms of restless legs syndrome. These fi ndings are consistent and build on those reported in the adult literature. keywords: Childhood onset restless legs syndrome, attention def...

Objective Substance use is a significant and common problem among school-aged youths throughout Africa. Like other countries on this continent, the West-African nation of Liberia is recovering from civil war. A well-educated population of young people is critical to the recovery efforts and long-term success of Liberia. Substance use by school-aged youths has important public health consequences that could undermine Liberia’s post-conflict recovery efforts. We wanted to better understand the culturally significant themes and subthemes related to substance use among youths attending public schools in Monrovia, Liberia. Methods A qualitative research design was used to collect data from 72 students attending public school in Monrovia, Liberia. Nine focus groups of 6–8 students from three public schools were facilitated using a semi-structured format to guide discussions on substance use. Student narratives were translated and re-occurring themes and subthemes were coded and analyzed. Results Four emergent themes described in this study were: Behaviors associated with substance use Consequences associated with individual use Consequences of substance use that affected the school milieu School-related factors that were protective from substance use. Subthemes associated with substance use included concealment of substances, intoxication and disruption of the classroom environment, expulsion from school, school drop-out, and school as protective against substance use. Conclusion Liberian school-aged youths described important themes and subthemes associated with substance use occurring within the school milieu. These data have germane public health ramifications, and could help inform larger epidemiologic study methods and public health interventions for Liberia and countries with similar profiles.

Oocyte maturation is dependent on a complex program of morphological, ultrastructural, and biochemical signaling events, and if disrupted could lead to decreased fertility and population decline. The in vitro sensitivity of amphibian oocytes and oocyte maturation to plant growth factor and widely used hormonal herbicide, 2,4-dichlorophenoxyacetic acid (2,4-D), was examined in this study to determine its potential impact on early development and possible contribution to the global amphibian decline. Progesterone, which acts through a membrane receptor, triggers meiotic maturation in full grown (stage VI) Xenopus oocytes, characterized by cytoskeletal reorganization, nuclear dissolution, chromosome condensation, and spindle formation. Biochemically, the Mos/MAPK/MPF signaling pathway is activated, in part dependent on translational activation of specific maternal mRNAs such as c-Mos. Light microscopy revealed unusual asymmetric morphotypes in oocytes exposed to 2,4-D alone characterized by a white spot and bulge, termed coning, in the animal pole where the germinal vesicle (nucleus) persisted intact. Treatment of oocytes with cytochalasin B, a microfilament inhibitor, blocked these morphotypes but nocodazole, a microtubule depolymerizing agent, did not. Confocal microscopy showed that 2,4-D, itself, caused substantial depolymerization of perinuclear microtubules. Importantly, 2,4-D blocked progesterone-induced maturation as measured by the lack of nuclear breakdown, confirmed by the lack of Mos expression, MPF activation, and cytoplasmic polyadenylation of cyclin B1 mRNA. However, Western blot analysis and U0126 inhibitor studies showed that 2,4-D, either alone or in the presence of progesterone, induced MAPK phosphorylation through MAPKK. These results show that 2,4-D disrupts oocyte cytoskeletal organization and blocks maturation while stimulating an independent MAPK signaling pathway.

Despite widely published speculation regarding a potential potency advantage of short-wavelength (blue-appearing) light for Seasonal Affective Disorder (SAD) treatment, there have been few systematic studies. Those comparing short-wavelength to broad-wavelength (white) light under actual clinical conditions suggest equivalent effectiveness. This multicenter, parallel-group design trial was undertaken to compare the effects of light therapy on SAD using blue (~465nm) versus blue-free (595–612nm) LED lights. Fifty-six medication-free subjects aged 21–64 years who met DSM-IV-TR criteria for recurrent major depression with winter-type seasonal pattern were enrolled in this blinded study at 5 participating centers between January and March 2012. Thirty-five subjects met criteria for randomization to 30 minutes of either blue (~465nm) or blue-free (595–612nm) daily morning light therapy. Twenty-nine subjects completed the study; three subjects withdrew due to treatment-related adverse events, including migraines, and three withdrew for non-study-related reasons. The primary effectiveness variable was depression score (SIGH-ADS) after six weeks of daily light treatment. Secondary effectiveness variables included Quality of Life and suicidality ratings. Using an intent-to-treat analysis, mean depression scores were different at baseline for the blue group (29±5 vs. 26±5, p=0.05 blue vs. blue-free, respectively), and initial score was used as a covariate. Baseline scores were not significantly different between treatment groups among those who completed the study, and no significant differences in depression scores were observed after 6 weeks (mean ± s.d. scores at 6 weeks: 5.6±6.1 vs. 4.5±5.3, p=0.74, blue vs. blue-free, respectively). In addition, the proportion of subjects who met remission criteria, defined as a depression score ≤8, was not significantly different between the two groups (p=0.41); among the 29 subjects who completed the study, 76% of subjects experienced remission by the end of the trial, which coincided with the beginning of spring. Quality of Life and suicidality ratings were also significantly improved from pre- to post-treatment, with no significant difference between treatments. No subject experienced worsening or non-improved symptoms over the 6-week trial. The main finding of this study is that subjects treated with blue light did not improve more than subjects treated with blue-free light; both showed substantial improvement on multiple measures. Failure to find differences may have resulted from methodological constraints, including a small sample size. Recruitment began mid-winter during an unusually mild season, and the trial was terminated earlier than planned by the study sponsor due to a failure to detect difference. However, if confirmed in a larger randomized sample, these results suggest that blue wavelengths are not necessary for successful SAD treatment.