Persistent membrane translocation of protein kinase C alpha during 12-0-tetradecanoylphorbol-13-acetate-induced apoptosis of LNCaP human prostate cancer cells

Others have reported that the phorbol ester 12-0-tetradecanoylphorbol-13-acetate (TPA), an activator and down-regulator of most protein kinase C (PKC) isozymes, can induce apoptotic cell death of androgen-sensitive LNCaP but not androgen-insensitive PC-3 or DU 145 human prostate cancer cells. As a first step toward uncovering the mechanism by which TPA induces apoptosis of LNCaP cells, we quantified expression of PKC isozyme mRNAs in unmodified and TPA-resistant LNCaP cells and in naturally TPA-resistant PC-3, PC-3M, and DU 145 cells. All of the cell lines and normal prostate expressed RNAs for PKC alpha, delta, epsilon, eta, and mu; only DU 145 cells and normal prostate expressed PKC beta and theta RNAs, and none expressed PKC gamma. The amount of PKC alpha RNA and protein was 6- to 38-fold lower, and PKC mu RNA was 4.5- to 16.5-fold higher in unmodified and TPA-resistant LNCaP cells than in the androgen-independent cells. We examined the effects of TPA on PKC alpha and mu mRNA levels and on membrane translocation of PKC alpha. Incubation with TPA for 6 h or more induced 95% inhibition of cell growth, a transient 12-fold increase and 5-fold decrease in PKC alpha and mu mRNA levels, respectively, and prolonged translocation of PKC alpha to non-nuclear membranes in unmodified LNCaP cells and in TPA-resistant LNCaP cells from which TPA had been removed for 10 days. TPA-resistant LNCaP cells in the continuous presence of TPA, or 24 h after removal of TPA, had down-regulated PKC alpha and remained resistant to re-addition of TPA. These data demonstrate a strong correlation of the presence and absence of membrane PKC alpha with apoptosis and resistance to apoptosis, respectively.     

Ultrastructure of spermiogenesis of Dipylidium caninum (Cestoda, Cyclophyllidea, Dipylidiidae), an intestinal parasite of Canis familiaris

We describe for the first time the ultrastructure of spermiogenesis of a representative of the family Dipylidiidae, Dipylidium caninum. Spermiogenesis begins with the formation of a differentiation zone. This conical area presents two centrioles with associated striated roots. One of the centrioles develops a flagellum and posteriorly a proximodistal fusion is produced between the axoneme and a median cytoplasmic process. In a final stage of spermiogenesis a condensation of electron-dense material between cortical microtubules is observed in the anterior part of the differentiation zone. This is the origin of the crest-like body that appears at the end of spermiogenesis. The presence of striated roots associated with centrioles constitutes the first report of these structures in the spermiogenesis of a cyclophyllidean cestode.     

A system for the analysis of seat support surfaces using surface shape control and simultaneous measurement of applied pressures

Chronic aspiration in the neurologically impaired child is associated with significant medical and social complications. Traditional surgical management has often relied on tracheotomy. This may well fail to control aspiration. The purpose of this retrospective study was to determine which neurologically impaired children would benefit from a laryngotracheal separation (LTS), as opposed to tracheotomy, as the primary surgical procedure to control chronic salivary aspiration. Patient selection was based on neurologic status, verbal communication ability, likelihood of neurologic recovery, and failure of previous treatments to control aspiration. Nineteen neurologically impaired children aged 8-172 months with chronic salivary aspiration underwent LTS. A total of 73.6% of these patients had prior tracheotomies, yet they continued to aspirate. Two early and three late complications were noted. No instances of fistula formation were noted. There were no deaths related to complications of the surgery or persistent aspiration. Follow-up 1-62 months after surgery demonstrated that complete control of the aspiration was achieved in all of these children. Two of the children who had achieved verbal communication prior to the procedure lost this ability. Improved general health and ability to resume oral intake was noted in all patients. This, combined with a decrease in the need of frequent suctioning, was felt by the families of these children to be a major improvement in the quality of life. Laryngotracheal separation appears to be a simple and effective means of controlling chronic aspiration. It should be considered as a primary treatment of aspiration in the properly selected child with neurologic disease.