[I]Vasoactive intestinal peptide binding in rodent suprachiasmatic nucleus: Developmental and circadian studies

The suprachiasmatic nucleus (SCN) of rat and hamster have been studied extensively and shown to play critical roles in circadian rhythmicity. [¹²⁵I]Vasoactive intestinal peptide (VIP) binding levels are high in the rat SCN, suggesting that VIP receptors may be an important component of SCN function. In contrast to previously demonstrated diurnal variations in VIP immunoreactivity and VIP mRNA, the present study found [¹²⁵I]VIP binding to be stable across the light-dark cycle in both rat and hamster SCN. High [¹²⁵I]VIP labeling appeared to be coextensive with the rat SCN but extended somewhat beyond the cytoarchitectonic boundaries of the hamster SCN. Binding density in hamster SCN was slightly higher than in rat. In the developing rat SCN, [¹²⁵I]VIP binding levels distinguished the SCN on embryonic day 18, and appeared to increase to postnatal day 10 before declining to adult levels. The early presence of [¹²⁵I]VIP binding suggests possible involvement of VIP receptors in fetal entrainment of circadian rhythms.     

Guidelines for dispensing medications

Federal and state codes exist regarding administering and dispensing medications and there is variation between the two. Recognition of the differences is imperative for the athletic trainer, who has traditionally dispensed these agents in compliance with established legal and professional guidelines. Statutes that apply to classifying, documenting, prescribing, dispensing, labeling, and housing medications by athletic trainers are presented as a baseline for this article. State and local regulations should be consulted to clarify differences existing at various governmental levels. These guidelines are provided to assist athletic trainers in properly dispensing medications.     

Honeybee colony integration: worker-worker interactions mediate hormonally regulated plasticity in division of labor.

Adult workers in honeybee (Apis mellifera) colonies exhibit plasticity in hormonally regulated, age-based division of labor by altering their pattern of behavioral development in response to changes in colony conditions. One form of this plasticity is precocious development: levels of juvenile hormone increase prematurely and bees begin foraging as much as 2 weeks earlier than average. We used two experimental paradigms inspired by developmental biology to study how bees obtain information on changing colony needs that results in precocious foraging. An analog of "cell culture," with bees reared outside of colonies in different sized groups, revealed that worker-worker interactions exert quantitative effects on endocrine and behavioral development. "Transplants" of older bees to colonies otherwise lacking foragers demonstrated that worker-worker interactions also affect behavioral development in whole colonies. These results provide insights to a long-standing problem in the biology of social insects and further highlight similarities in the integration of activity that exist between individuals in insect colonies and cells in metazoans.     

Acute lymphocytosis after trauma--early recognition of the high-risk patient?

An absolute lymphocyte count is included in the routine results provided by most automated blood cell counters, providing a prompt indication of peripheral blood lymphocytosis. Transient lymphocytosis is seen in many acutely ill patients, including those with multiple injuries. We have observed a significantly higher death rate among trauma patients with lymphocytosis at presentation; patients with lymphocytosis, on subsequent assessment of injury, proved to have higher Injury Severity Scores than those without lymphocytosis. Investigation of lymphocyte subsets in nine patients with lymphocytosis showed an increase in T cells, reversal of the CD4:CD8 ratio, and, in seven patients, an increase in "natural killer" cells. The presence of lymphocytosis and its early detection as part of a routine blood count may supply a readily available means of identifying a high-risk trauma patient.     

Genotypic and phenotypic variability of 22q11.2 microduplications: An institutional experience

Duplications in the 22q11.2 region can cause 22q11.2 duplication syndrome and encompass a variety of phenotypes including developmental delays, facial abnormalities, cardiovascular defects, central nervous system delays, and other congenital abnormalities. However, the contribution of these contiguous duplicated regions to the clinical phenotypes has not been fully elucidated. In this study, we identified nine patients carrying different 22q11.2 microduplications detected by chromosomal microarray. Of these patients, seven pediatric patients presented with various clinical features including two neonate cases died shortly after birth, and two healthy adults. We examined region specific genotype–phenotype associations and found unpredictability associated with 22q11.2 duplications in these nine patients.     

ETV6/RUNX1 fusion at diagnosis and relapse: some prognostic indications

This study was undertaken in order to compare the interphase and metaphase cytogenetics of 28 patients with ETV6/RUNX1 positive acute lymphoblastic leukemia, at diagnosis and relapse. The median time to relapse was 26 months. The significant fusion positive population heterogeneity revealed at interphase by a commercial probe for ETV6/RUNX1 fusion has not been described before. Six diagnostic samples had a single abnormal population; others had up to five each, which differed in the numbers of RUNX1 signals, and in the retention or loss of the second ETV6 signal. In contrast, the number of fusion signals was more constant. At relapse, there were fewer populations; the largest or unique clone was sometimes a re-emergence of a minor, diagnostic one, with a retained copy of ETV6 and the most RUNX1 signals. Abnormal, fusion negative clones were identified in bone marrow samples at extra-medullary relapse. Variant three or four-way translocations, which involved chromosomes 12 and 21, were prominent among the complex rearrangements revealed by metaphase FISH. The frequency of their occurrence at diagnosis and reappearance at relapse, sometimes accompanied by minor clonal evolution, was another new observation. Other recurrent cytogenetic features included a second copy of the fusion signal in six cases, partial duplication of the long arm of the X chromosome in two cases, and trisomy 10 in three cases. In comparing our data with previously reported cases, a picture is beginning to emerge of certain diagnostic features, which may provide circumstantial evidence of an increased risk of relapse.