CD66 receptor specificity exhibited by neisserial Opa variants is controlled by protein determinants in CD66 N-domains

Neisseria gonorrhoeae strain MS11 is able to express 11 different opacity (Opa) proteins on its outer surface. A number of these Opa proteins have been shown to function as adhesins through binding of CD66 receptors present on human cells. CD66 antigens, or carcinoembryonic antigen family members, constitute a family of glycoproteins belonging to the immunoglobulin superfamily. Opa variants recognize this class of receptors in a differential manner such that certain Opa variants recognize up to four different CD66 receptors (CD66a, -c, -d, and -e), whereas others recognize only two (CD66a and -e) or none. We explored the basis for this receptor tropism in the present study. Our data show that glycoforms of CD66e and deglycosylated CD66e are recognized by gonococci in an Opa-specific manner. Binding by Opa variants of recombinant N-terminal domains of CD66 receptors expressed in Escherichia coli reflected the adherence specificities of Opa variants to HeLa cells expressing native CD66 molecules. These data indicate that recognition of CD66 receptors by Opa variants is mediated by the protein backbone of the CD66 N-domains. Furthermore, by using chimeric constructs between different CD66 N-domains we identified distinct binding regions on the CD66e N-domain for specific groups of Opa variants, suggesting that the differential recognition of CD66 receptors by Opa variants is dictated by the presence of specific binding regions on the N-domain of the receptor.     

Follow-up of partial seizure progression in an infant

OBJECTIVE AND MATERIAL: We are carried out a retrospective study of 43 patients, 21 males and 22 women entered during the period of infancy in the Service of Neurology of our hospital and with diagnostic of any type of partial seizure, in an intent to correlate a series of clinical parameters, electroneurophysiologics and initial therapeutics with their factors follow-up periods. RESULTS: They are a half age of 7.11 months (1-19), consecutive being controlled for a period of time of 40 months (6-96). We have settled down a relationship between the drugs utilized in the first seizure and that other that they remained in their last revision, the current state of the critical manifestations, and the existence or not of an agreement between the e diagnosis emitted to the discharge and the development of the illness. CONCLUSION: After the present study, we thought that the current classification of the epileptic seizures is insufficient in the age of the infant, with presages much more complexes.     

Visualising bioprocesses using ‘3D‐Windows of Operation’

The operation of bioprocesses involves handling many variables with complex interactions. The visualisation of interactions is vital if suitable conclusions are to be drawn. This paper extends the previously developed ‘Windows of Operation’ to three dimensions, enabling the effects of three parameters to be visualised simultaneously. A tool with a graphical user interface has been developed to enable the generation of ‘3D‐Windows of Operation’ and the visualisation of the effects of the variation of any three control variables. Its use is illustrated with simulations of enzyme production. A number of control variables and the effects of the imposition of constraints on the range of possible operating values are investigated. Changes in the range possible are related to the variation in specific constraints or variables. Finally, it is illustrated how these diagrams and operation heuristics may be used to select suitable operating conditions for the bioprocess. Copyright © 2004 Society of Chemical Industry     

The yeast spindle pole body is assembled around a central crystal of Spc42p

The spindle pole body (SPB) is the microtubule organizing center (MTOC) in the yeast Saccharomyces that plays a pivotal role in such diverse processes as mitosis, budding, and mating. We have used cryoelectron microscopy and image processing to study the structure of isolated diploid SPBs. We show that SPBs are present in two lateral-size classes, sharing a similar vertical architecture comprised of six major layers. Tomographic reconstructions of heparin-stripped SPBs reveal a central hexagonally packed layer. Overexpression of Spc42p results in the growth of a similar layer, forming a crystal that encircles the SPB. Hence, the SPB is an MTOC that utilizes crystallographic packing of subunits in its construction.     

Bcmd governs recruitment of new B cells into the stable peripheral B cell pool in the A/WySnJ mouse

BACKGROUND & AIMS: Nitric oxide is synthesized from L-arginine and is metabolized to nitrate and nitrite. This study evaluates the effects of a pharmacological blockade of NO synthesis on fluid transport by the inflamed gallbladder mucosa. METHODS: Experiments were performed in cats with cholecystitis and in control animals. NO synthase activity was measured in gallbladder tissue; the enzyme was characterized by immunoblotting techniques and localized by immunofluorescence. Fluid transport and release of nitrate and nitrite by the gallbladder mucosa and bile and bile salt secretion from the liver were registered simultaneously in vivo. RESULTS: Fluid secretion in inflamed gallbladders was reversed to a net absorption in response to the NO synthase blockers N omega-nitro-L-arginine and aminoguanidine, and formation of nitrate was reduced. The effects were reversed by L-arginine. Increased levels of inducible NO synthase in inflamed gallbladders were shown by immunoblotting, by immunofluorescence (mainly in macrophages), and by Ca(2+)-independent [3H]citrulline formation from [3H]arginine. The NO synthase blockers had no effect on gallbladder fluid transport in normal gallbladders. CONCLUSIONS: Increased levels of inducible NO synthase activity are shown in inflamed gallbladders, and a pharmacological blockade of this enzyme blocks fluid secretion and decreases nitrate release from the mucosa.