Effects of carbaryl, permethrin, 4-nonylphenol, and copper on muscarinic cholinergic receptors in brain of surrogate and listed fish species

Advances in understanding the pathogenesis of multiple sclerosis have already identified treatments that modestly modify the course of the disease. Future efforts will depend increasingly on how well we apply the insights of therapeutic immunology to the inhibition of the sequence of events which generates an inflammatory process within the central nervous system and targets this to myelinated axons. The timing and choice of treatments will be increasingly determined by correlations between the sequence of events that leads to inflammation, demyelination and axon degeneration and the clinical course of the disease. Successful limitation of the disease processes may have the unexpected dividend of also promoting repair of intact axons; but, if not, parallel efforts will have to be directed at remyelination through applied neurobiology and it makes sense to explore strategies for both limiting and repairing the damage.     

Transient lectin binding by white matter tract border zone microglia in the foetal rabbit brain

Axonal growth cones of developing white matter tracts are guided through the cerebrum by interactions with cell surface and extracellular matrix molecules expressed by glial cells that mediate cell adhesion and contact-dependent inhibition. Specific carbohydrates are considered essential for the proper functioning of these molecular complexes. We studied developmental aspects of complex carbohydrate expression by white matter glia in the foetal rabbit brain using the tomato lectin Lycopersicon esculentum, which has affinity for components of the extracellular matrix proteins and cell surface proteins (N-acetylglucosamine) and activated lysosomal membrane glycoproteins (N-acetyllactosamine). Concentrations of the lectin-positive glia were transiently found immediately adjacent to developing white matter tracts of the foetal rabbit brain from 22 to 32 days' gestation. The number of positive cells markedly diminished by the fourth post-natal day and in the adult brain. The lectin-positive glia did not react with antibody to glial fibrillary acidic protein. However, they did express the macrophage surface antigen, Mac-1, indicating that the lectin binding reflected the presence of microglial activated lysosomal membranes. These data suggest that, in addition to their role as central nervous system scavengers, microglia are involved in a specifically timed function in the neurodevelopmental programme of white matter tract formation.     

Methylguazone, vindesine and cisplatin for the treatment of patients with relapsed or refractory malignant lymphoma: an Eastern Cooperative Oncology Group Study (PA482)

A new regimen not cross-resistant with standard regimens was developed for patients with relapsed or refractory Hodgkin's disease and non-Hodgkin's lymphoma. The regimen consisted of cisplatin, 70 mg/M2 given intravenously on day 1, vindesine, 3 mg/M2 given intravenously on days 1 and 8 (and also on day 15 of the first cycle only), and methylguazone, 600 mg/M2 given intravenously on days 8 and 15. Courses were repeated every 21 days. Thirty-nine patients (35 with non-Hodgkin's and 4 with Hodgkin's lymphoma) were treated and all were evaluable for response and toxicity. There were 5 complete and 14 partial responses for a total response rate of 49% (C.I. = 35%-63%). The median durations of partial and complete response were only 2.8 and 4.2 months, respectively. Only one patient remained in complete response for more than a year. There was one treatment-related death from renal failure on the study. Although this regimen was, in general. well tolerated the results are disappointing and seem no better than those obtained with many other salvage regimens for lymphoma.     

New helper cells and matched early region 1-deleted adenovirus vectors prevent generation of replication-competent adenoviruses

The presence of replication-competent adenoviruses (RCAs) in batches of replication-defective adenovirus (Ad) vectors is a major problem for the application of these vectors in gene therapy. RCAs are generated by recombination between sequences in the Ad vector and homologous Ad sequences in the helper cells, resulting in the acquisition by the vector of early region 1. To prevent the formation of RCAs, we have developed helper cell lines, which we named PER, and matched Ad vectors that do not have sequence overlap. PER cells contain the Ad serotype 5 (Ad5) E1A- and E1B-encoding sequences (Ad5 nucleotides 459-3510) under the control of the human phosphoglycerate kinase (PGK) promoter. We demonstrate that PER cells synthesize high levels of the Ad5 E1A and E1B proteins. The yields from PER cells of E1-deleted Ads are similar to those obtained from earlier helper cells, such as 911 and 293 cells. Propagation of matched Ad vectors, which lack Ad5 nucleotides 459-3510, in one of the PER clones, PER.C6, does not result in the generation of RCAs, in contrast to propagation in 293 cells. We conclude that the combination of PER.C6 cells and nonoverlapping E1-deleted adenoviral vectors eliminates the problem of RCA generation by homologous recombination, and allows cost-effective production of safe, clinical-grade batches of recombinant Ad vectors.     

Crystallization and preliminary X-ray diffraction analysis of gingipain R2 from Porphyromonas gingivalis in complex with H-D-Phe-Phe-Arg-chloromethylketone

Gingipain R2 is a 50 kDa proteinase from the oral pathogenic bacterium Porphyromonas gingivalis. This proteinase, which displays no significant sequence homology to any protein previously analyzed by X-ray crystallography, has been crystallized using the vapor diffusion method. Two different crystal forms were obtained from a solution containing polyethylene glycol (MW 8,000) (space group P2(1)2(1)2(1)) or magnesium sulfate (space group R3) as precipitating agent. Complete diffraction data sets have been collected up to 2.0 and 2.9 A resolution, respectively. Cell dimensions are a = 51.9 A, b = 79.9 A, and c = 99.6 A (P2(1)2(1)2(1)), and a = b = 176.6 A, and c = 143.4 A (R3). Considerations of the possible values of Vm accounts for the presence of one monomer per asymmetric unit in the case of the orthorhombic crystal form, whereas the rhombohedral crystal form, together with the analysis of the self-rotation function, could accommodate a tetramer in the asymmetric unit.     

Effect of ultrasound on the release of micro-encapsulated drugs

Although ultrasound is used extensively in medical therapies and diagnostics, it has been recognized only recently as a method for external controlled diversity of drugs. In this paper, firstly, a literature review on drug delivery and the combination with ultrasound is given. Then an experiment is described on measuring the release of a model drug (hexabrix) under ultrasound irradiation, from a polymer carrier.     

Transjugular intrahepatic portosystemic shunt: midterm clinical and angiographic follow-up

The synthesis of a series of azabicyclic indole esters is described and their potency reported as 5-HT4 receptor antagonists. Optimization of the most potent compound (19) by preparing the corresponding oxazino[3,2-a]indole ester afforded 34, which had a pIC50 of 9.5 in the guinea pig distal colon longitudinal muscle myenteric plexus preparation.