Additive effect of TAp63 deficiency on the adrenocortical dysplasia (acd) phenotype

Adrenocortical dysplasia (acd) is a spontaneous autosomal recessive mouse mutation exhibiting caudal truncation, vertebral segmentation defects, hydronephrosis, limb hypoplasia, and perinatal lethality. Acd encodes TPP1, a component of the shelterin complex that maintains telomere integrity, and consequently acd mutant mice have telomere dysfunction and genomic instability. We previously showed that apoptosis is the primary mechanism causing the acd skeletal phenotype, and that p53 deficiency rescues the skeletal defects of the acd phenotype but has no effect on the perinatal lethality. The Trp63 gene encodes multiple isoforms, which play a role in proliferation, apoptosis, and stem/progenitor cell maintenance. Different p63 isoforms exhibit both proapoptotic (TAp63) and antiapoptotic (ΔNp63) functions. We hypothesized that deficiency of proapoptotic TAp63 isoforms might rescue the acd skeletal phenotype, similar to our previous observations with deficiency of p53. Mice heterozygous for a null allele of TAp63 were crossed to heterozygous acd mice to determine the effect of TAp63 deficiency on the acd mutant phenotype. In contrast to our results with the acd?×?p53 cross, skeletal anomalies were not rescued by deficiency of TAp63. In fact, the limb and vertebral anomalies observed in double-mutant embryos were more severe than those of embryos with the acd mutation alone, demonstrating a dose-dependent effect. These studies suggest that TAp63 isoforms do not facilitate p53-like apoptosis during development in response to acd-mediated telomere dysfunction and are consistent with the proposed roles of TAp63 in maintaining genomic stability.     

Penetrating chest wound: a case report.

An unusual penetrating chest injury was caused by a ball-point pen. Because of apparent penetration of the heart, preparations were made for an emergency open-heart procedure before emergency thoracotomy was undertaken, with the pen still in situ. The pen had bruised the epicardium but had not penetrated the pericardial sac. After removal of the pen, the wound was closed and a chest tube left in place. Recovery, apart from minor degrees of basal atelectasis, pleural effusion and wound infection, was uneventful. The outcome was consistent with that associated with current aggressive management of penetrating chest injuries. Management is based on three approaches. The primary one is intercostal thoracostomy tube drainage and fluid and blood replacement. In cases of massive hemorrhage or air leak, thoracotomy is necessary. The third approach is to prevent post-traumatic pulmonary insufficiency by using fine, high-efficiency filters during blood transfusion, avoiding excessive administration of intravenous fluids, performing tracheostomy after prolonged endotracheal intubation, and using a volume respirator with positive end-expiratory pressure. The average mortality for penetrating wounds of the heart is 25%.     

Differential gene expression from microarray analysis distinguishes woven and lamellar bone formation in the rat ulna following mechanical loading

Formation of woven and lamellar bone in the adult skeleton can be induced through mechanical loading. Although much is known about the morphological appearance and structural properties of the newly formed bone, the molecular responses to loading are still not well understood. The objective of our study was to use a microarray to distinguish the molecular responses between woven and lamellar bone formation induced through mechanical loading. Rat forelimb loading was completed in a single bout to induce the formation of woven bone (WBF loading) or lamellar bone (LBF loading). A set of normal (non-loaded) rats were used as controls. Microarrays were performed at three timepoints after loading: 1 hr, 1 day and 3 days. Confirmation of microarray results was done for a select group of genes using quantitative real-time PCR (qRT-PCR). The micorarray identified numerous genes and pathways that were differentially regulated for woven, but not lamellar bone formation. Few changes in gene expression were evident comparing lamellar bone formation to normal controls. A total of 395 genes were differentially expressed between formation of woven and lamellar bone 1 hr after loading, while 5883 and 5974 genes were differentially expressed on days 1 and 3, respectively. Results suggest that not only are the levels of expression different for each type of bone formation, but that distinct pathways are activated only for woven bone formation. A strong early inflammatory response preceded an increase in angiogenic and osteogenic gene expression for woven bone formation. Furthermore, at later timepoints there was evidence of bone resorption after WBF loading. In summary, the vast coverage of the microarray offers a comprehensive characterization of the early differences in expression between woven and lamellar bone formation.     

Control of Echinothrips americanus on lima bean by Franklinothrips vespiformis crawford using supplemental food

BioControl - Supplemental food application to crops as a resource for generalist predators has shown utility for promoting their establishment and persistence leading to enhanced biological control...     

The presence of SV40 T-antigen is not required for cytochalasin B-induced multinucleation

Two cell lines temperature-sensitive for the expression of SV40 virus T-antigen were studied to determine if T-antigen is responsible for the uncontrolled nuclear division found in transformed cells treated with cytochalasin B. Multinucleation is found at temperatures at which T-antigen is not immunologically detectable suggesting that T-antigen is not necessary for cytochalasin B-induced multinucleation.