Ultrafast X-Ray Diffraction Studies of the Phase Transitions and Equation of State of Scandium Shock Compressed to 82 GPa.

Using x-ray diffraction at the Linac Coherent Light Source x-ray free-electron laser, we have determined simultaneously and self-consistently the phase transitions and equation of state (EOS) of the lightest transition metal, scandium, under shock compression. On compression scandium undergoes a structural phase transition between 32 and 35 GPa to the same bcc structure seen at high temperatures at ambient pressures, and then a further transition at 46 GPa to the incommensurate host-guest polymorph found above 21 GPa in static compression at room temperature. Shock melting of the host-guest phase is observed between 53 and 72 GPa with the disappearance of Bragg scattering and the growth of a broad asymmetric diffraction peak from the high-density liquid.

Campylobacter Species and Neutrophilic Inflammatory Bowel Disease in Cats.

BACKGROUND: Inflammatory bowel disease (IBD) is a common cause of signs of gastrointestinal disease in cats. A subset of cats with IBD has neutrophilic inflammation of the intestinal mucosa. HYPOTHESIS: Neutrophilic enteritis in cats is associated with mucosal invasion by microorganisms, and specifically Campylobacter spp. ANIMALS: Seven cats with neutrophilic IBD and 8 cats with lymphoplasmacytic IBD. METHODS: Retrospective review of duodenal biopsy specimens that were collected endoscopically for histologic examination. Cases were identified and selected by searching the histopathology archive for cats with a diagnosis of neutrophilic and lymphoplasmacytic IBD. Fluorescence in situ hybridization (FISH) targeting either all eubacteria or individual Campylobacter spp. was performed on archived samples. Neutrophils were detected on the same samples using a FISH probe for neutrophil elastase. RESULTS: Campylobacter coli was present in (6/7) cats with neutrophilic IBD and in (1/8) cats with lymphoplasmacytic IBD (P = .009). Cats with neutrophilic IBD had significantly higher number of C. coli (median bacteria 0.7/hpf) in the mucosa than cats with lymphoplasmacytic IBD (median bacteria 0/hpf) (P = 0.002). Colocalization of neutrophils and C. coli was demonstrated, with C. coli closer to the neutrophils than any other bacteria (P < .001). CONCLUSIONS AND CLINICAL IMPORTANCE: Identification of C. coli associated with neutrophilic inflammation suggests that C. coli is able either to produce compounds which stimulate neutrophils or to induce feline intestinal cells to produce neutrophil chemoattractants. This association should allow a directed therapeutic approach in cats with neutrophilic IBD, potentially improving outcome and reducing any zoonotic risk.

Inelastic response of silicon to shock compression.

The elastic and inelastic response of [001] oriented silicon to laser compression has been a topic of considerable discussion for well over a decade, yet there has been little progress in understanding the basic behaviour of this apparently simple material. We present experimental x-ray diffraction data showing complex elastic strain profiles in laser compressed samples on nanosecond timescales. We also present molecular dynamics and elasticity code modelling which suggests that a pressure induced phase transition is the cause of the previously reported 'anomalous' elastic waves. Moreover, this interpretation allows for measurement of the kinetic timescales for transition. This model is also discussed in the wider context of reported deformation of silicon to rapid compression in the literature.

Endochondral fracture healing with external fixation in the Sost knockout mouse results in earlier fibrocartilage callus removal and increased bone volume fraction and strength.

Sclerostin deficiency, via genetic knockout or anti-Sclerostin antibody treatment, has been shown to cause increased bone volume, density and strength of calluses following endochondral bone healing. However, there is limited data on the effect of Sclerostin deficiency on the formative early stage of fibrocartilage (non-bony tissue) formation and removal. In this study we extensively investigate the early fibrocartilage callus. Closed tibial fractures were performed on Sost(-/-) mice and age-matched wild type (C57Bl/6J) controls and assessed at multiple early time points (7, 10 and 14days), as well as at 28days post-fracture after bony union. External fixation was utilized, avoiding internal pinning and minimizing differences in stability stiffness, a variable that has confounded previous research in this area. Normal endochondral ossification progressed in wild type and Sost(-/-) mice with equivalent volumes of fibrocartilage formed at early day 7 and day 10 time points, and bony union in both genotypes by day 28. There were no significant differences in rate of bony union; however there were significant increases in fibrocartilage removal from the Sost(-/-) fracture calluses at day 14 suggesting earlier progression of endochondral healing. Earlier bone formation was seen in Sost(-/-) calluses over wild type with greater bone volume at day 10 (221%, p<0.01). The resultant Sost(-/-) united bony calluses at day 28 had increased bone volume fraction compared to wild type calluses (24%, p<0.05), and the strength of the fractured Sost(-/-) tibiae was greater than that that of wild type fractured tibiae. In summary, bony union was not altered by Sclerostin deficiency in externally-fixed closed tibial fractures, but fibrocartilage removal was enhanced and the resultant united bony calluses had increased bone fraction and increased strength.

Spatial control of bone formation using a porous polymer scaffold co-delivering anabolic rhBMP-2 and anti-resorptive agents.

Current clinical delivery of recombinant human bone morphogenetic proteins (rhBMPs) utilises freeze-dried collagen. Despite effective new bone generation, rhBMP via collagen can be limited by significant complications due to inflammation and uncontrolled bone formation. This study aimed to produce an alternative rhBMP local delivery system to permit more controllable and superior rhBMP-induced bone formation. Cylindrical porous poly(lactic-co-glycolic acid) (PLGA) scaffolds were manufactured by thermally-induced phase separation. Scaffolds were encapsulated with anabolic rhBMP-2 (20 µg) ± anti-resorptive agents: zoledronic acid (5 µg ZA), ZA pre-adsorbed onto hydroxyapatite microparticles, (5 µg ZA/2% HA) or IkappaB kinase (IKK) inhibitor (10 µg PS-1145). Scaffolds were inserted in a 6-mm critical-sized femoral defect in Wistar rats, and compared against rhBMP-2 via collagen. The regenerate region was examined at 6 weeks by 3D microCT and descriptive histology. MicroCT and histology revealed rhBMP-induced bone was more restricted in the PLGA scaffolds than collagen scaffolds (-92.3% TV, p < 0.01). The regenerate formed by PLGA + rhBMP-2/ZA/HA showed comparable bone volume to rhBMP-2 via collagen, and bone mineral density was +9.1% higher (p < 0.01). Local adjunct ZA/HA or PS-1145 significantly enhanced PLGA + rhBMP-induced bone formation by +78.2% and +52.0%, respectively (p ≤ 0.01). Mechanistically, MG-63 human osteoblast-like cells showed cellular invasion and proliferation within PLGA scaffolds. In conclusion, PLGA scaffolds enabled superior spatial control of rhBMP-induced bone formation over clinically-used collagen. The PLGA scaffold has the potential to avoid uncontrollable bone formation-related safety issues and to customise bone shape by scaffold design. Moreover, local treatment with anti-resorptive agents incorporated within the scaffold further augmented rhBMP-induced bone formation.

Psittacid herpesvirus 3 infection in the eclectus parrot (Eclectus roratus) in Australia.

Psittacid herpesvirus 3 (PsHV-3) has recently been implicated as the cause of a severe respiratory disease in Bourke's parrots (Neopsephotus bourkii) in the United States. In this report, the clinical manifestations and gross and microscopic lesions of PsHV-3 infection in 2 eclectus parrots (Eclectus roratus) in Australia are described. The presence of a PsHV-3 infection was confirmed by polymerase chain reaction amplification and sequencing of PsHV-3 DNA using degenerate and PsHV-3 primers. Electron microscopy of infected cells demonstrated the assembly of herpesvirus virions as well as intranuclear tubular structures. The detection of PsHV-3 in Australia in 2 eclectus parrots broadens the list of known affected species and confirms the presence of this virus in Australia.

A modular and optimized single marker system for generating Trypanosoma brucei cell lines expressing T7 RNA polymerase and the tetracycline repressor.

Here, we present a simple modular extendable vector system for introducing the T7 RNA polymerase and tetracycline repressor genes into Trypanosoma brucei. This novel system exploits developments in our understanding of gene expression and genome organization to produce a streamlined plasmid optimized for high levels of expression of the introduced transgenes. We demonstrate the utility of this novel system in bloodstream and procyclic forms of Trypanosoma brucei, including the genome strain TREU927/4. We validate these cell lines using a variety of inducible experiments that recapture previously published lethal and non-lethal phenotypes. We further demonstrate the utility of the single marker (SmOx) TREU927/4 cell line for in vivo experiments in the tsetse fly and provide a set of plasmids that enable both whole-fly and salivary gland-specific inducible expression of transgenes.

Evaluation of a multifaceted intervention to limit excessive antipsychotic co-prescribing in schizophrenia out-patients.

OBJECTIVE: To evaluate the effect of a multifaceted educational intervention on the frequency of antipsychotic co-prescribing in adult schizophrenia out-patients. METHOD: Controlled quasi-experimental study performed in two Danish municipalities matched for baseline prevalence of antipsychotic polypharmacy, socioeconomic status and functional level of patients. The intervention was aimed at psychiatric healthcare providers and consisted of 1 day of didactic lectures, six 3-h educational outreach visits and an electronic reminder during drug prescribing. RESULTS: Between-group use of antipsychotic polypharmacy was compared at baseline (intervention group, N = 232/control group, N = 351) and after 1 year of intervention (intervention group, N = 216/control group, N = 386). The prevalence of antipsychotic polypharmacy at follow-up was not significantly different between treatment settings when adjusting for differences in case-mix (P = 0.07). CONCLUSION: This multifaceted educational intervention failed to reduce the frequency of antipsychotic co-prescribing, but it suggested that future efforts to improve prescribing practice should address organizational barriers to implementation.

N-acetyl D-glucosamine stimulates growth in procyclic forms of Trypanosoma brucei by inducing a metabolic shift.

SUMMARYThe lectin-inhibitory sugars D-glucosamine (GlcN) and N-acetyl D-glucosamine (GlcNAc) are known to enhance susceptibility of the tsetse fly vector to infection with Trypanosoma brucei. GlcNAc also stimulates trypanosome growth in vitro in the absence of any factor derived from the fly. Here, we show that GlcNAc cannot be used as a direct energy source, nor is it internalized by trypanosomes. It does, however, inhibit glucose uptake by binding to the hexose transporter. Deprivation of D-glucose leads to a switch from a metabolism based predominantly on substrate level phosphorylation of D-glucose to a more efficient one based mainly on oxidative phosphorylation using L-proline. Procyclic form trypanosomes grow faster and to higher density in D-glucose-depleted medium than in D-glucose-rich medium. The ability of trypanosomes to use L-proline as an energy source can be regulated depending upon the availability of D-glucose and here we show that this regulation is a graded response to D-glucose availability and determined by the overall metabolic state of the cell. It appears, therefore, that the growth stimulatory effect of GlcNAc in vitro relates to the switch from D-glucose to L-proline metabolism. In tsetse flies, however, it seems probable that the effect of GlcNAc is independent of this switch as pre-adaptation to growth in proline had no effect on tsetse infection rate.

Analysis of a cross between green and red fluorescent trypanosomes.

Trypanosoma brucei undergoes genetic exchange in its insect vector, but the mechanism is unknown and no one has yet seen the process. By crossing genetically engineered red and green fluorescent trypanosomes, we have been able to pinpoint the location of genetic exchange in the fly and search for intermediate stages. In experimental crosses of red and green parental trypanosomes, yellow hybrid trypanosomes first appeared in the fly salivary glands as early as 13 days after infection and were observed only in flies with a mixture of red and green trypanosomes in one or both salivary glands. Despite high numbers of flies with mixed infections, yellow trypanosomes were not detected in the fly midgut or proventriculus. The hybrid nature of yellow trypanosomes was confirmed by analysis of molecular karyotypes and microsatellite alleles. As well as yellow hybrids, hybrid trypanosomes with red, green or no fluorescence were also recovered from fly salivary glands. Analysis of microsatellite alleles in parental and progeny clones showed Mendelian inheritance. Our findings are consistent with the hypothesis that mating takes place between trypanosomes in the salivary glands of the fly before they attach to the salivary gland epithelium.

Multiple effects of the lectin-inhibitory sugars D-glucosamine and N-acetyl-glucosamine on tsetse-trypanosome interactions.

We are studying early events in the establishment of Trypanosoma brucei in the tsetse midgut using fluorescent trypanosomes to increase visibility. Feeding flies with the lectin-inhibitory sugars D-glucosamine (GlcN) or N-acetyl-glucosamine (GlcNAc) has previously been shown to enhance fly susceptibility to infection with trypanosomes and, as expected, we found that both sugars increased midgut infection rates of Glossina morsitans morsitans with T. brucei. However, GlcNAc did not show the inhibitory effect on salivary gland infection rate reported previously for GlcN. Both sugars significantly slowed the movement of the bloodmeal along the midgut. GlcN also significantly increased the size of the bloodmeal taken and fly mortality. The most surprising finding was that GlcNAc stimulated trypanosome growth not only in the midgut, but also in vitro in the absence of any factor derived from the fly. Thus our direct comparison of the effects of GlcN and GlcNAc on the trypanosome-tsetse interaction has shown that these sugars impact on trypanosome growth and tsetse physiology in different ways and are not interchangeable as suggested in the literature. The sugars cause multiple effects, not restricted solely to the inhibition of midgut lectins. These findings have implications for current models of tsetse susceptibility to trypanosome infection.

Volatile compounds from Salix spp. varieties differing in susceptibility to three willow beetle species.

The volatile compounds emitted by leaves of 10 willow varieties that differ in their susceptibility to damage by blue (Phratora vulgatissima), brassy (P. vitellinae), and brown (Galerucella lineola) willow beetles were examined both before and after mechanical damage and correlated with feeding preferences of these beetles determined under laboratory conditions. Three compounds were identified from intact undamaged leaves of six willow varieties, namely cis-3-hexenyl acetate, cis-3-hexenol, and benzaldehyde. After mechanical damage, the yield and number of volatile compounds increased for all varieties. There were significant differences among willow varieties for both the concentration of cis-3-hexenyl acetate and the relative proportion of this compound to cis-3-hexenol (green leaf volatile ratio). The 10 varieties collectively showed a significant negative correlation between the relative resistance of each variety to blue and brown willow beetles and the yield of cis-3-hexenyl-acetate from damaged plants. The green leaf volatile ratio of damaged plants was also negatively correlated with the relative resistance of willow variety to these two beetle species.

Aberrant behavioral effects of a dopamine D1 receptor antagonist and agonist in monkeys: evidence of uncharted dopamine D1 receptor actions.

BACKGROUND: Basic research indicates a role for dopamine (DA) D1 antagonism in the treatment of schizophrenia. Clinical trials have not confirmed any role. Besides the defining second messenger (adenylyl cyclase [AC]), DA D1 receptors are linked to other effectors (e.g., phospholipase C [PLC]). Differing actions of DA D1 antagonists upon differing effectors could explain conflicting results between the lab/clinic. METHODS: In a monkey model in which behavioral effects of DA D1 antagonists/agonists have been well characterized we examined: 1) SKF 83959, biochemically, a DA D1 antagonist, behaviorally a DA D1 agonist, and 2) SKF 83822, biochemically, a DA D1 agonist, which, unlike all previously tested DA D1 agonists, does not also stimulate PLC. SKF 83959 and SKF 83822 were given alone and combined with DA D1 and D2 agonists, antagonists, and dextroamphetamine (AMP). RESULTS: SKF 83959 acted as a DA D1 agonist (induced oral dyskinesia given alone, counteracted DA D1 antagonist [NNC 756], induced dystonia, and did not inhibit AMP induced behaviors). SKF 83822, unlike previously studied DA D1 agonists, did not induce dyskinesia, but resulted in a state of extreme arousal and locomotor activation without stereotypy, effectively counteracted by NNC 756, but not by SKF 83959 nor raclopride (DA D2 antagonist). CONCLUSIONS: It is hypothesized that: 1) dyskinesia is linked to PLC stimulation; 2) DA D1 agonism can play a role in the induction of psychosis, via a mechanism linked neither to AC nor PLC, and 3) DA D1 antagonists differ in antipsychotic potential, possibly via this unidentified mechanism.

Acoustic startle eyeblink response after acute exercise.

The acoustic startle eyeblink response (ASER) is a useful probe for investigating central nervous system activity associated with emotional responses to aversive and appetitive stimuli. Though the ASER is sensitive to change in emotional arousal, the effect of acute physical exertion on ASER has not been reported. We examined changes in ASER amplitude and latency in 26 healthy young men (24+/-5 yr) after 20 min of cycling at light and hard intensities (40% and 75% VO2peak) and after 20 min of quiet rest. Mixed model ANCOVA, controlling precondition scores, indicated no effects for ASER amplitude or latency in either sedentary or active participants (p>.10). Our findings indicate that possible effects of acute exercise on potentiated startle or ASER responses elicited by positive or negative foreground stimuli should not be expected to be confounded by an altered baseline acoustic startle eyeblink response when measured in healthy young men.

Extrapyramidal side effects during chronic combined dopamine D1 and D2 antagonist treatment in Cebus apella monkeys.

Previous studies in non-human primates have shown that tolerance to dystonia occurs during chronic dopamine D1 (D1) but not D2 antagonism and induction/aggravation of oral dyskinesia (TD) during D2 but not D1 antagonism. We were therefore interested in determining the effects of combined chronic D1 + D2 antagonism on dystonia and dyskinesia. To this intent, 8 male Cebus apella monkeys were treated 10 weeks with gradually increasing doses of D1 antagonist (NNC 112) + a D2 antagonist (raclopride), followed by 2 weeks of treatment with the D2 antagonist alone. Due to previous neuroleptic exposure, 5 monkeys had TD and all were sensitized to dystonia. During the combined antagonist treatment, tolerance to dystonia occurred; the tolerance disappearing upon discontinuation of the D1 antagonist and continuation of the D2 antagonist alone. Parallel to these results, improvement of TD was seen during the combined antagonist treatment with worsening during the D2 antagonist alone. Both the combined antagonists and the D2 antagonist alone resulted in moderate/severe bradykinesia, with no tolerance. These findings indicate that supplementation of traditional D2 antagonism with a D1 antagonist would lessen the risk of dystonia and allow alleviation of preexisting TD, though parkinsonian side effects might still occur. The findings further indicate that separate dopaminergic mechanisms control dystonia/dyskinesia and parkinsonism.

New and old antipsychotics versus clozapine in a monkey model: adverse effects and antiamphetamine effects.

RATIONALE: Neuroleptic primed Cebus apella monkeys have proven reliable in screening antipsychotics for extrapyramidal side effect (EPS) potential in humans, and the ratio EPS liability/antiamphetamine efficacy ["therapeutic index" (TI)] has fit well with clinical results. OBJECTIVES: 1) To find the TIs of one new (quetiapine), three potential [NNC 756 (dopamine (DA) D1 antagonist), NNC 22-0031 (alpha-1 adrenergic/5-HT2 serotonergic/DA D1 and D2 antagonist) and DOD 647 (DA D1 and D2 antagonist)] and three old antipsychotics (haloperidol, melperone and clozapine), 2) to test the model further and 3) to gain more insight as to clozapine's neuropharmacology. METHODS: Seven monkeys received haloperidol daily for 2 years; all were sensitized to dystonia. All drugs were given SC, in increasing doses until two animals had dystonia/other adverse effects (AE), and in decreasing doses with a fixed dose of dextroamphetamine producing motor unrest and stereotypies, to find the minimum significant antiamphetamine dose (AA). The ratio AE/AA = TI. RESULTS: Excepting clozapine and DOD 647, all drugs induced dystonia. At 2-4 mg/kg, clozapine caused uncoordinated movements, myoclonic jerks and rough tremor; unlike dystonia, the syndrome was not alleviated but worsened by the anticholinergic, biperiden. DOD 647 up to 2 mg/kg had no adverse effects. The TIs of the new and potential antipsychotics were 3-5 versus 4 for clozapine and 1 for haloperidol and melperone, suggesting that like clozapine, these new drugs will not produce EPS at antipsychotic doses.

Chronic dopamine D1, dopamine D2 and combined dopamine D1 and D2 antagonist treatment in Cebus apella monkeys: antiamphetamine effects and extrapyramidal side effects.

To determine: (1) whether the apparent lack of efficacy of dopamine D1 (D1) antagonists in the clinic might be attributable to development of tolerance to antipsychotic effects; and (2) whether combined D1 and D2 antagonism might contribute to clozapine's clinical profile, eight Cebus apella monkeys were chronically treated with a D1 antagonist (NNC 756) ((+)-8-chloro-7-hydroxy-3-methyl-5-(7-(2,3- dihydrobenzofuranyl)-2,3,4,5-tetrahydro-1H-3-benzazepine), a D2 antagonist (raclopride) or a combination of the two antagonists. Prior neuroleptic exposure had resulted in oral dyskinesia in seven monkeys and sensitization to dystonia in all, yielding a model for acute and chronic extrapyramidal side effects (EPS). Dextroamphetamine-induced motoric unrest and stereotypies were used as a psychosis model. We found tolerance toward dystonic symptoms during D1 and D1 + D2 treatments but not during D2 treatment. D2 but not D1 or D1 + D2 antagonism caused exacerbation of dyskinesia. Both D1 and D1 + D2 antagonism were superior to D2 antagonism alone in counteracting the amphetamine-induced behaviors, with no tolerance to antiamphetamine effects. These findings suggest: (1) reasons other than tolerance (e.g., differences among antagonists) may explain the lack of efficacy in clinical trials with D1 antagonists; and (2) that D1 antagonism alone or combined and modest D1 and D2 antagonism offers the potential of antipsychotic efficacy with a lower risk of EPS than traditional D2 antagonism. Further clinical trials with D1 or combined D1 and D2 antagonists are, therefore, recommended.

Thermal balloon and rollerball ablation to treat menorrhagia: a multicenter comparison.

OBJECTIVE: To compare the clinical efficacy and safety of a thermal uterine balloon system with hysteroscopic rollerball ablation in the treatment of dysfunctional uterine bleeding. METHODS: Two hundred fifty-five premenopausal women were treated in a randomized multicenter study comparing thermal uterine balloon therapy with hysteroscopic rollerball ablation for the treatment of menorrhagia. Preprocedural and postprocedural menstrual diary scores and quality-of-life questionnaires were obtained. Twelve-month follow-up data are presented on 239 women. RESULTS: Twelve-month results indicated that both techniques significantly reduced menstrual blood flow with no clinically significant difference between the two groups as reflected by return to normal bleeding or less (balloon 80.2% and rollerball ablation 84.3%). Multiple quality-of-life questionnaire results were also similar, including percent of patients highly satisfied with their results (balloon 85.6% compared with rollerball 86.7%). A 90% decrease in diary scores was seen in more than 60% of patients in both groups. Procedural time was reduced significantly in the uterine balloon therapy group. Intraoperative complications occurred in 3.2% of the hysteroscopic rollerball patients, whereas no intraoperative complications occurred in the thermal balloon group. CONCLUSION: In the treatment of dysfunctional uterine bleeding, uterine balloon therapy is as efficacious as hysteroscopic rollerball ablation and may be safer.