Natural variation of submergence tolerance among Arabidopsis thaliana accessions.

• The exploitation of natural variation in Arabidopsis thaliana (Arabidopsis) provides a huge potential for the identification of the molecular mechanisms underlying this variation as a result of the availability of a vast array of genetic and genomic resources for this species. Eighty-six Arabidopsis accessions were screened for natural variation in flooding tolerance. This forms the first step towards the identification and characterization of the role of candidate genes contributing to flooding tolerance. • Arabidopsis accessions at the 10-leaf stage were subjected to complete submergence in the dark. Survival curves were plotted to estimate median lethal times as a measure of tolerance. Flooding-associated survival parameters, such as root and shoot oxygen content, initial carbohydrate content and petiole elongation under water, were also measured. • There was a significant variation in submergence tolerance among Arabidopsis accessions. However, the order of tolerance did not correlate with root and shoot oxygen content or initial amounts of shoot starch and total soluble sugars. A negative correlation was observed between submergence tolerance and underwater petiole elongation. • Arabidopsis accessions show considerable variation in the ability to tolerate complete submergence, making it a good species in which to identify and characterize genes and to study mechanisms that contribute to survival under water.

Characteristics of perpetrators in homicide-followed-by-suicide incidents: National Violent Death Reporting System--17 US States, 2003-2005.

Homicide-followed-by-suicide (referred to as "homicide-suicide") incidents are rare events but can have a profound impact on families and communities. A better understanding of perpetrator characteristics and how they compare with those of other homicide suspects and suicide decedents might provide insight into the nature of these violent acts. This report is based on 2003-2005 data from 17 US states participating in the National Violent Death Reporting System, a unique, incident-based, active surveillance system that integrates data on violent deaths from multiple sources. Of the 408 homicide-suicide incidents identified, most incidents were committed with a firearm (88.2%) and perpetrated by males (91.4%), those over 19 years of age (97.6%), and those of white race (77.0%); however, just over half of filicide (killing of children)-suicides (51.5%) were perpetrated by females. Over 55% of male homicide-suicide perpetrators versus 26.4% of other male suicide decedents had prior intimate partner conflicts (P < 0.001). In fact, having a history of intimate partner conflicts was even common among homicide-suicide perpetrators who did not victimize their intimate partners. Recognition of the link between intimate partner conflicts and homicide-suicide incidents and strategies involving collaboration among the court/legal and mental health systems might prevent these incidents.

Inhaled steroids and the risk of adrenal suppression in children.

Corticosteroids are the mainstay of treatment of all asthma severity levels in adults and children. With their widespread use comes a responsibility to monitor, understand, and balance their efficacy and safety. Systemic adverse effects such as adrenal suppression have been clearly associated with the use of oral corticosteroids and to a lesser degree with the use of inhaled corticosteroids (ICS). In clinical trials, adrenal suppression is more evident when ICS are used in long-term therapy and at higher doses. However, monitoring adrenal suppression during short-term therapy and at lower doses is still of value in order to ascertain the lower limit of an inhaled corticosteroid's safety profile. Significant adrenal suppression at conventional ICS doses appears to be rare in clinical practice. When evaluating the effect of ICS on the hypothalamo-pituitary-adrenal-axis (HPA-axis), one must consider sources of variability both within and among trials including test sensitivity, systemic bioavailability, degree of airway obstruction, and delivery devices. All of these factors have the potential to effect the level of adrenal suppression detected and must be considered when interpreting HPA-axis test results in research or practice. This review will discuss adrenal suppression found with common ICS.

Transfer of cytoplasm from newBeta CMS sources to sugar beet by asymmetric fusion : 1. Shoot regeneration from mesophyll protoplasts and characterization of regenerated plants.

For our program on the transfer of cytoplasmic male sterility (CMS) by cybridization inBeta vulgaris L. (sugar beet), we have developed a procedure for the isolation and culture of mesophyll protoplasts of sugar beet followed by shoot regeneration. A prerequisite proved to be the presence in the media of n-propylgallate (nPG), a lipoxygenase inhibitor. Sustained divisions were found in all accessions that were tested. Plating efficiencies and regeneration ability varied greatly from one experiment to the other and appeared to be accession-dependent. Shoots could be easily transferred to soil. A majority of the regenerants (72%) retained the diploid chromosome number. Somaclonar variation in phenotype was low (4.9%). Mitochondrial DNA probes, capable of discriminating different cytoplasms ofBeta spp. showed no rearrangements due to the protoplast and in vitro culture phase, indicating that these probes can be used to identify cybrids after asymmetric fusions. The data presented here open up possibilities for genetic engineering using protoplasts in one of the world's most important arable crops.