Methods and method evaluation for mycotoxins

Mycotoxins are metabolites of molds frequently found on and in agricultural commodities, food and feeds. Owing to their demonstrated acute, sub-acute and, in some cases, chronic toxicity, an effort has been made, worldwide, to control human and animal exposure to these toxic chemicals. This effort depends upon the availability of validated analytical methods for their detection and quantitation. This paper outlines the methodology available, and the procedures used to validate, i.e. evaluate, these methods based on the use of interlaboratory collaborative studies and the application of the HORRAT.     

Biological activity of Manduca sexta allatotropin-like peptides,predicted products of tissue-specific and developmentally regulated alternatively spliced mRNAs

The insect neuropeptide, allatotropin (Manse-AT), exerts multiple functions including the stimulation of juvenile hormone (JH) biosynthesis in adults and the inhibition of active ion transport across the midgut epithelium of feeding larvae. The Manse-AT gene is expressed in multiple regions of the nervous system as three mRNAs that differ by alternative splicing. The specific mRNA isoform present differs in a tissue- and developmental-specific manner thus providing a mechanism for the regulated production of peptides specific to each isoform. These peptides are predicted to include three allatotropin-like (Manse-ATL) peptides that exhibit limited structural identity to Manse-AT and overlapping biological activities.     

Retinoblastoma: from bench to bedside

Retinoblastoma (Rb) is the most common primary ocular malignancy of children and is caused by a mutation in the gene RB1. Approximately 40% of cases are associated with one or more constitutional mutations, and are therefore heritable, whereas the other 60% are sporadic. Rb is exclusively found in young children. In some cases, Rb tumours metastasise to extraocular organs including bone, lung and brain. Although there is no effective treatment for metastatic disease, non-metastatic cases can be cured by removal of the eye(enucleation). Newer treatment strategies emphasise salvaging the affected eye whenever possible. Animal models of Rb have been developed with xenograft and transgenic techniques. Each model has both strengths and weaknesses for exploring the mechanisms of disease development and progression and the efficacy of new treatment strategies.     

Harmonic analysis of perfusion pumps

The controversy over the use of nonpulsatile versus pulsatile pumps for maintenance of normal organ function during ex vivo perfusion has continued for many years, but resolution has been limited by lack of a congruent mathematical definition of pulsatility. We hypothesized that the waveform frequency and amplitude, as well as the underlying mean distending pressure are all key parameters controlling vascular function. Using discrete Fourier Analysis, our data demonstrate the complexity of the pulmonary arterial pressure waveform in vivo and the failure of commonly available perfusion pumps to mimic in vivo dynamics. In addition, our data show that the key harmonic signatures are intrinsic to the perfusion pumps, are similar for flow and pressure waveforms, and are unchanged by characteristics of the downstream perfusion circuit or perfusate viscosity.     

Updated classification of hemangiomas and other vascular anomalies

Vascular anomalies comprise a widely heterogenous group of tumors and malformations. Great confusion has arisen because of the term hemangioma has been and is continued to be used to represent a multitude of vascular entities. This review presents the updated classification of vascular anomalies with the goal of clarifying the term hemangioma. In addition, newer clinical concepts in hemangiomas and other vascular tumors is presented. Hemangioma subtypes and hemangioma variants are also discussed, and a brief review of pyogenic granuloma and Kaposiform hemangioendothelioma is provided. Finally, the immunohistochemical marker GLUT1 is reviewed, a marker that heralds a new era in vascular anomalies research.