Acceptor specificity of the human leukocyte alpha3 fucosyltransferase: role of FucT-VII in the generation of selectin ligands

The alpha3 fucosyltransferase, FucT-VII, is one of the key glycosyltransferases involved in the biosynthesis of the sialyl Lewis X (sLex) antigen on human leukocytes. The sialyl Lewis X antigen (NeuAcalpha(2-3)Galbeta(1-4)[Fucalpha(1-3)]GlcNAc-R) is an essential component of the recruitment of leukocytes to sites of inflammation, mediating the primary interaction between circulating leukocytes and activated endothelium. In order to characterize the enzymatic properties of the leukocyte alpha3 fucosyltransferase FucT-VII, the enzyme has been expressed in Trichoplusia ni insect cells. The enzyme is capable of synthesizing both sLexand sialyl-dimeric-Lexstructures in vitro , from 3'-sialyl-lacNAc and VIM-2 structures, respectively, with only low levels of fucose transfer observed to neutral or 3'-sulfated acceptors. Studies using fucosylated NeuAcalpha(2-3)-(Galbeta(1- 4)GlcNAc)3-Me acceptors demonstrate that FucT-VII is able to synthesize both di-fucosylated and tri-fucosylated structures from mono- fucosylated precursors, but preferentially fucosylates the distal GlcNAc within a polylactosamine chain. Furthermore, the rate of fucosylation of the internal GlcNAc residues is reduced once fucose has been added to the distal GlcNAc. These results indicate that FucT-VII is capable of generating complex selectin ligands, in vitro , however the order of fucose addition to the lactosamine chain affects the rate of selectin ligand synthesis.      

The effect of salts on the kinetics of iron release from N-terminal and C-terminal monoferrictransferrins

The kinetics of iron release from N-terminal and C-terminal monoferric human transferrins has been studied using EDTA as the accepting chelate. In the absence of added salts iron release from the N-terminal site is more facile but the relative lability can be reversed by the addition of NaClO₄, NaCl and LiCl. The results indicate that both anions and cations can affect the lability of the two sites. Since the relative lability of the two monoferrictransferrins is affected by fairly moderate concentrations of NaCl and NaClO₄ we suggest that the ionic composition serum may play an important role in determining the observed distribution of iron among the sites. A new method for the preparation of N-terminal monoferrictransferrin is described.     

Application of beta-irradiation through the struts of a previously deployed stent

The application of beta-radiation in coronary arteries is a promising new technique for the treatment of in-stent restenosis. This is the first case in which the 5 F. delivery catheter of the Beta-Cath trade mark system was advanced through the struts of a stent, previously deployed in an adjacent branch, so as to deliver radiation to the target vessel.     

Morphological differences among egg nests and adult individuals of Cicadatra persica (Hemiptera,Cicadidae), distributed in Erneh,Syria

The aim of this study is determining the different patterns of egg nests and the morphological differences between the specimens of Cicadatra persica Kirkalidy, 1909 (Hemiptera: Cicadidae) distributed in fruit orchards in Erneh located on AL-Sheikh mountain south west of Syria. The appearance of 80 egg nests was studied, and the results showed that there were two basic patterns of egg nests laid by Cicadatra persica, 90% of the egg nests were of the first pattern (consists of several adjacent slits), while 10% of them were of the second pattern (consists of several divergent slits). A random sample consisting of 300 specimens (150 males and 150 females) were also studied concentrating on the differences in the color of the supra-antennal plate and in the number of spurs on the tibia of the hind legs. The results showed that there were two basic patterns of individuals based on the differences in the color of supra-antennal plate. The first pattern (individuals with yellow supra-antennal plates), constituted more than 90%, and the second one (individuals with black supra-antennal plates) constituted less than 10%. The results also showed that there were 27 different patterns based on the number of spurs on the tibia of the hind legs. One of them was a common pattern (2, 3) whose individuals have 2 spurs on the upper side of the tibia of the hind legs and 3 spurs on the lateral side of the tibia of the hind legs. The total percent of this common pattern was 76%. The other 26 patterns were different from each other, and the total percent of all these different patterns was 24%.     

Collagenase predigestion on paraffin sections enhances collagen immunohistochemical detection without distorting tissue morphology

Reliable immunohistochemical detection of collagen in formalin fixed, paraffin embedded tissues requires protease digestion. While these pan-proteases (pepsin, trypsin, protease K, etc.) enhance collagen detection, they also digest many other tissue proteins and produce poor cellular morphology and unrecognizable cellular structures. Balancing the conditions (protease type, concentration, incubation time and temperature) to digest some, but not all, proteins in a tissue section while optimizing collagen detection requires one to compromise improved collagen immunolabeling with adequate cellular morphology. Furthermore, optimal conditions for digesting tissue proteins to enhance collagen detection vary among tissue types and their fixation. Although brain is not typically subject to these deleterious consequences, structures such as epithelium, spermatids, stroma etc. and other tissues with complicated histology are profoundly affected. To resolve this technical dilemma, we discovered a novel use for collagenase to enhance collagen immunodetection without affecting the noncollagen proteins, thereby preserving tissue morphology. Collagenase, which is typically used in vitro for disassociation of cells, has never been used reliably on formalin fixed, paraffin embedded tissue sections. This new use of collagenase for immunohistochemistry promotes increased collagen immunolabeling, is easy to use, is versatile, and allows preservation of tissue structure that provides maximal and accurate histological information.     

The Human Phenotype Ontology: Semantic Unification of Common and Rare Disease

The Human Phenotype Ontology (HPO) is widely used in the rare disease community for differential diagnostics, phenotype-driven analysis of next-generation sequence-variation data, and translational research, but a comparable resource has not been available for common disease. Here, we have developed a concept-recognition procedure that analyzes the frequencies of HPO disease annotations as identified in over five million PubMed abstracts by employing an iterative procedure to optimize precision and recall of the identified terms. We derived disease models for 3,145 common human diseases comprising a total of 132,006 HPO annotations. The HPO now comprises over 250,000 phenotypic annotations for over 10,000 rare and common diseases and can be used for examining the phenotypic overlap among common diseases that share risk alleles, as well as between Mendelian diseases and common diseases linked by genomic location. The annotations, as well as the HPO itself, are freely available.     

Beneficial effect of a short-acting NO donor for the prevention of neointimal hyperplasia

Nitric oxide (NO)-based therapies effectively inhibit neointimal hyperplasia in animal models of arterial injury and bypass grafting, but are not available clinically. We created a simple, effective, locally applied NO-eluting therapy to prevent restenosis after vascular procedures. We investigated the efficacy of perivascular delivery of two distinctly different diazeniumdiolate NO donors, 1-[2-(carboxylato)pyrrolidin-1-yl]diazen-1-ium-1,2-diolate (PROLI/NO) (short half-life) and diazeniumdiolated poly(acrylonitrile) (PAN/NO) (long half-life), in powder or gel form (30% poloxamer 407), at inhibiting neointimal hyperplasia using the rat carotid artery injury model. Two weeks postinjury, all of the NO-eluting therapies successfully reduced neointimal hyperplasia. However, most dramatically, PROLI/NO powder reduced intimal area by 91.2% (p<0.05) versus injury alone. PROLI/NO powder was noted to reduce the medial area (40.2% vs injury alone, p<0.05), whereas other groups showed no such effect. Three days postinjury, each NO treatment group significantly reduced cellular proliferation. However, inflammatory markers revealed a distinct pattern: PAN/NO groups displayed increased leukocyte infiltration (p<0.05), whereas PROLI/NO groups displayed less macrophage infiltration (p<0.05). In conclusion, perivascular delivery of diazeniumdiolate NO donors in powder or gel form effectively inhibits neointimal hyperplasia. Application of short-acting PROLI/NO powder most effectively inhibited neointimal hyperplasia and inflammation and may represent a simple, clinically applicable NO-eluting therapy to prevent neointimal hyperplasia and restenosis after open vascular interventions.