Sucrose and proton cotransport in Ricinus cotyledons

In Ricinus cotyledons, evidence for proton extrusion came from observation of direct acidification of the medium in the presence of potassium salts. Increasing K⁺ influx with increasing pH suggested a link between K⁺ influx and H⁺ efflux by an H⁺ pump. The kinetics of K⁺ influx and H⁺ efflux were consistent with a 1:1 stoichiometry K⁺:H⁺, which may indicate either electrical coupling or carrier mediated exchange. The results were consistent with an H⁺ pump setting up an electrochemical potential gradient which provides the driving force for an H⁺-sucrose cotransport and the movement of K⁺. With reference to this, a model for phloem loading is suggested.     

Dynamic Localization of Tat Protein Transport Machinery Components in Streptomyces coelicolor

The Tat pathway transports folded proteins across the bacterial cytoplasmic membrane and is a major route of protein export in the Streptomyces genus of bacteria. In this study, we have examined the localization of Tat components in the model organism Streptomyces coelicolor by constructing enhanced green fluorescent protein (eGFP) and mCherry fusions with the TatA, TatB, and TatC proteins. All three components colocalized dynamically in the vegetative hyphae, with foci of each tagged protein being prominent at the tips of emerging germ tubes and of the vegetative hyphae, suggesting that this may be a primary site of Tat secretion. Time-lapse imaging revealed that localization of the Tat components was highly dynamic during tip growth and again demonstrated a strong preference for apical sites in growing hyphae. During aerial hypha formation, TatA-eGFP and TatB-eGFP fusions relocalized to prespore compartments, indicating repositioning of Tat components during the Streptomyces life cycle.     

Tension headaches

In order to assess the effectiveness of verbal relaxation instructions and EMG relaxation training on the relief of tension headaches, 18 medically documented tension-headache sufferers were randomly assigned to one of three conditions:(1) Jacobson-Wolpe autogenic-relaxation training,(2) EMG relaxation training, or(3) EMG relaxation training combined with Jacobson-Wolpe autogenic instructions. The two EMG-assisted groups showed significantly better results, compared to the verbal group, in terms of reduction of headache activity and the rate at which reduction took place. Thus, EMG-assisted relaxation procedures seem the treatment method of choice for relief of tension headaches.     

Synthesis and evaluation of alkoxy-phenylamides and alkoxy-phenylimidazoles as potent sphingosine-1-phosphate receptor subtype-1 agonists

In the design of potent and selective sphingosine-1-phosphate receptor agonists, we were able to identify two series of molecules based on phenylamide and phenylimidazole analogs of FTY-720. Several designed molecules in these scaffolds have demonstrated selectivity for S1P receptor subtype 1 versus 3 and excellent in vivo activity in mouse. Two molecules PPI-4621 (4b) and PPI-4691 (10a), demonstrated dose responsive lymphopenia, when administered orally.     

Lymphocyte proliferative responses to separated bovine herpesvirus 1 proteins in immune cattle.

The immune response to bovine herpesvirus 1 (BHV-1) infection can protect cattle from subsequent challenge with the virus. This protection involves a variety of defensive strategies, and the activation of most of these defenses requires the recognition of viral proteins by the cellular immune system. To identify some of the BHV-1 proteins recognized by T lymphocytes, we measured in vitro proliferative responses to individual proteins. Viral proteins were separated by gel electrophoresis followed by Western immunoblotting, and immunoblots were evaluated for serological reactions. Unstained blotted fractions were processed into antigen-bearing particles for analysis in blastogenesis assays. Purified BHV-1 proteins obtained by immunoadsorbent chromatography were processed and included for comparison in both enzyme-linked immunosorbent and proliferation assays. The tegument protein VP8 and the glycoprotein gIV appeared to be the antigens which most consistently stimulated the proliferation of lymphocytes from BHV-1-immunized animals. Positive blastogenic responses were also detected to gI, gIII, and to one or more uncharacterized, low-molecular-weight proteins in some of the cattle tested. These results indicate that T-lymphocyte proliferative responses to BHV-1 proteins are detectable in immune cattle and may be important in protection from BHV-1 infection.     

Protocol of a prospective study on the diagnostic value of transcranial duplex scanning of the substantia nigra in patients with parkinsonian symptoms

Background  

Parkinson's disease (PD) is the second most common neurodegenerative disorder. As there is no definitive diagnostic test, its diagnosis is based on clinical criteria. Recently transcranial duplex scanning (TCD) of the substantia nigra in the brainstem has been proposed as an instrument to diagnose PD. We and others have found that TCD scanning of substantia nigra duplex is a relatively accurate diagnostic instrument in patients with parkinsonian symptoms. However, all studies on TCD so far have involved well-defined, later-stage PD patients, which will obviously lead to an overestimate of the diagnostic accuracy of TCD.     

Dispersal in a stream dwelling salmonid: Inferences from tagging and microsatellite studies

We used both direct (mark-recapture) andindirect (microsatellite analysis)methodologies to investigate dispersal betweentwo putative populations of brook charr (Salvelinus fontinalis) in Freshwater River,Cape Race, Newfoundland, Canada. Over a 5-yearstudy period, mark-recapture data revealed somemovement by fish, but the proportion ofrecaptured fish migrating from one populationarea to another was low (0–4.1%).Additionally, during sampling periods in thespawning seasons, no fish was found in thealternate population area to that of its firstcapture. Despite this pattern of limitedmovement, microsatellite analysis based onsixteen polymorphic loci provided no evidenceof genetic differentiation. Indirect estimatesof dispersal parameters varied greatly betweendifferent methods of analysis. While use of acoalescent-based model yielded estimatedmigration rates congruent with the results ofthe mark-recapture study, other methodsresulted in much higher estimates of migrationbetween the populations. In particular, thelack of genetic differentiation coupled withlikely violations of the assumed island modelprevented generation of meaningful estimates ofdispersal using F_st. The disparitiesbetween migration rates estimated from themark-recapture work and from the differentindirect methods highlight the difficulties ofusing indirect methods to estimate dispersal onan ecological timescale. However,mark-recapture methods can fail to detecthistorical or episodic movement that isimportant in an evolutionary context, and wetherefore argue that a combination of directand indirect methods can provide a morecomplete picture of dispersal than eitherapproach alone.     

Draft genome sequence of Streptomyces strain S4, a symbiont of the leaf-cutting ant Acromyrmex octospinosus

Streptomyces spp. are common symbionts of the leaf-cutting ant species Acromyrmex octospinosus, which feeds on basidiomycete fungus leaf matter and harvests the lipid- and carbohydrate-rich gongylidia as a food source. A. octospinosus and other ant genera use antifungal compounds produced by Streptomyces spp. and other actinomycetes in order to help defend their fungal gardens from parasitic fungi. Herein, we report the draft genome sequence of Streptomyces strain S4, an antifungal-producing symbiont of A. octospinosus.