Clinical usefulness of continuous administration ofNocardia rubra cell wall skeleton (N-CWS) in diffuse panbronchiolitis (DPB)

Eight patients with diffuse panbronchiolitis (DPB) who had repeated intractable airway infections were continuously treated withNocardia rubra cell wall skeleton (N-CWS), a biological response modifier. As a result, subjective symptoms were reduced in 6 patients. Antibiotics therapy could be discontinued completely in two patients and the dose of antibiotics could be reduced considerably in two other patients. No adverse reactions in relation to N-CWS were observed. These results suggest that N-CWS is effective in treating erythromycin-resistant DPB.Abbreviations BRM Biological response modifier - DPB Diffuse panbronchiolitis - EM erythromycin - N-CWS Nocardia rubra cell wall skeleton     

Large scale preparation and crystallization of neuron-specific enolase

A simple method has been developed for the large scale purification of neuron-specific enolase [EC 4.2.1.11]. The method consists of ammonium sulfate fractionation of brain extract, and two subsequent column chromatography steps on DEAE Sephadex A-50. The chromatography was performed on a short (25 cm height) and thick (8.5 cm inside diameter) column unit that was specially devised for the large scale preparation. The purified enolase was crystallized in 0.05 M imidazole-HCl buffer containing 1.6 M ammonium sulfate (pH 6.39), with a yield of 0.9 g/kg of bovine brain tissue.     

Flower-Inducing Activity of Phloem Exudates from Pharbitis cotyledons Exposed to Various Photoperiods

The phloem exudate prepared from the cotyledons of Pharbitisseedlings that had been exposed to a single dark period (oflonger than 10 h) induced flowering in cultured apices excisedfrom non-induced seedlings. The flower-inducing activity ofthe exudate increased as the seedlings were exposed to longerperiods of darkness. The highest activity was associated withthe exudate taken from cotyledons exposed to a single 16-h darkperiod. The activity of the exudate taken from cotyledons exposedto an inductive dark period was clearly reduced by interruptionof the dark period. The addition of exudate taken from threecotyledons to 10 ml of medium resulted in the highest flower-inducingactivity. About 50% of cultured apex explants formed floralbuds, even when the concentration of the exudate was reducedto 0.1 cotyledon equivalents per 10 ml of medium. The flower-inducingactivity of the exudate appeared to be heat-stable. (Received December 13, 1991; )     

Optical microscopy of Arabidopsis seedlings fixed in non-fresh FAA using Kennedy Fixation Tubes.

Samples will be kept in non-fresh fixative for longer period than usual in Kennedy Space Center Fixation Tubes (KFT) when they will be fixed for microscopy in the International Space Station (ISS). It is necessary to examine characteristics of samples prepared under such conditions and to improve preservation of the samples. In this study, morphology of Arabidopsis tissues prepared under such conditions was examined under a light microscope. Deformation of cell shape was observed in tissues with well-developed intercellular spaces when they were fixed in non-fresh fixative for longer period in KFTs.     

MHC interaction and T cell recognition of carbohydrates and glycopeptides.

The T cell independence of complex polysaccharide Ag has suggested the possibility that carbohydrates may be incapable of T cell recognition because of a failure to interact with MHC restriction elements and/or a failure of MHC/carbohydrate complexes to interact with and be recognized by Ag-specific TCR. We have used two approaches to obtain information about T cell recognition of carbohydrate. First, we have determined the capacity of a series of oligosaccharides and glycolipids to bind a murine class II MHC molecule, IAd. No significant binding was observed with the 26 compounds tested, but the limitation to these studies was that there was a relatively limited collection of synthetic carbohydrate and glycolipid structures of limited complexity available for analysis. The second approach involved the study of the effect of glycosylation of a known peptide T cell epitope (OVA 323-339) on MHC binding of the peptide and on T cell recognition. Three patterns of effects were observed: 1) no effect on either binding or T cell recognition. This pattern was observed when the carbohydrate was located at residues removed from the core MHC-binding region. When the carbohydrate was located within the core MHC-binding regions, either 2) glycosylation destroyed both MHC binding and T cell recognition; or 3) glycosylation did not ablate MHC binding or T cell recognition. In this latter instance, there was evidence to indicate that the carbohydrate moiety was an important part of the antigenic determinant recognized by T cells.     

Different forms of membrane-associated herpes simplex virus glycoproteins induce functionally distinct subsets of herpes simplex virus-specific suppressor T cells.

Previous studies have shown that two types of virus-specific suppressor T cells (Ts) are induced in mice made tolerant with herpes simplex virus (HSV)-infected spleen cells (SC). One type of Ts blocks the afferent phase of the delayed hypersensitivity response to HSV (Ts-aff), and the other blocks the efferent or effector phase (Ts-eff). In this report we show that the induction requirements for these suppressor populations differ. Injection of SC infected for 6 h with HSV at a multiplicity of infection of 5 or less or treated with heat-inactivated virus induced only Ts-aff. Similar results were seen with SC incubated for 90 min in virus-free preparations containing only viral proteins. In contrast, the Ts-eff population was induced only by SC treated for 6 h with infectious HSV at a multiplicity of infection of 10. Collectively, these data indicate that Ts-aff are induced by adsorbed HSV antigens on SC, whereas Ts-eff are induced by nascent HSV antigens expressed on infected SC. In addition to their induction requirements, the two types of regulatory cells differ in their expression of effector function. Ts-eff but not Ts-aff require a cyclophosphamide-sensitive target cell in the immune recipient for suppressor function. The possible identity of this target cell and the significance of the different induction requirements between the two types of Ts are discussed.     

CoaSim: A flexible environment for simulating genetic data under coalescent models

Background  

Coalescent simulations are playing a large role in interpreting large scale intra-specific sequence or polymorphism surveys and for planning and evaluating association studies. Coalescent simulations of data sets under different models can be compared to the actual data to test the importance of different evolutionary factors and thus get insight into these.