Alkaloid Quantities in Endophyte-Infected Tall Fescue are Affected by the Plant-Fungus Combination and Environment

Many grass species are symbiotic with systemic, vertically-transmitted, asymptomatic Epichloë endophytic fungi. These fungi often produce alkaloids that defend the host against herbivores. We studied how environmental variables affect alkaloids in endophyte-infected tall fescue (Schedonorus phoenix) from three Northern European wild origins and the widely planted US cultivar ‘Kentucky-31’ (KY31). The plants were grown in identical common garden experiments in Finland and Kentucky for two growing seasons. Plants were left as controls (C) or given water (W), nutrient (N) or water and nutrient (WN) treatments. For 8–10 replications of each plant origin and treatment combination in both experiments, we analyzed ergot alkaloids, lysergic acid, and lolines. In Finland, tall fescue plants produced 50 % more ergot alkaloids compared to plants of the same origin and treatments in Kentucky. Origin of the plants affected the ergot alkaloid concentration at both study sites: the wild origin plants produced 2–4 times more ergot alkaloids than KY31, but the ergot alkaloid concentration of KY31 plants was the same at both locations. Overall lysergic acid content was 60 % higher in plants grown in Kentucky than in those grown in Finland. Nutrient treatments (N, WN) significantly increased ergot alkaloid concentrations in plants from Finland but not in plants from Kentucky. These results suggest that the success of KY31 in US is not due to selection for high ergot alkaloid production but rather other traits associated with the endophyte. In addition, the environmental effects causing variation in alkaloid production of grass-endophyte combinations should be taken into account when using endophyte-infected grasses agriculturally.

Evidence for the role of EPHX2 gene variants in anorexia nervosa

Anorexia nervosa (AN) and related eating disorders are complex, multifactorial neuropsychiatric conditions with likely rare and common genetic and environmental determinants. To identify genetic variants associated with AN, we pursued a series of sequencing and genotyping studies focusing on the coding regions and upstream sequence of 152 candidate genes in a total of 1205 AN cases and 1948 controls. We identified individual variant associations in the Estrogen Receptor-ß (ESR2) gene, as well as a set of rare and common variants in the Epoxide Hydrolase 2 (EPHX2) gene, in an initial sequencing study of 261 early-onset severe AN cases and 73 controls (P=0.0004). The association of EPHX2 variants was further delineated in: (1) a pooling-based replication study involving an additional 500 AN patients and 500 controls (replication set P=0.00000016); (2) single-locus studies in a cohort of 386 previously genotyped broadly defined AN cases and 295 female population controls from the Bogalusa Heart Study (BHS) and a cohort of 58 individuals with self-reported eating disturbances and 851 controls (combined smallest single locus P<0.01). As EPHX2 is known to influence cholesterol metabolism, and AN is often associated with elevated cholesterol levels, we also investigated the association of EPHX2 variants and longitudinal body mass index (BMI) and cholesterol in BHS female and male subjects (N=229) and found evidence for a modifying effect of a subset of variants on the relationship between cholesterol and BMI (P<0.01). These findings suggest a novel association of gene variants within EPHX2 to susceptibility to AN and provide a foundation for future study of this important yet poorly understood condition.

Measurement of the T + T neutron spectrum using the national ignition facility

Neutron time-of-flight spectra from inertial confinement fusion experiments with tritium-filled targets have been measured at the National Ignition Facility. These spectra represent a significant improvement in energy resolution and statistics over previous measurements, and afford the first definitive observation of a peak resulting from sequential decay through the ground state of (5)He at low reaction energies E(c.m.) 100 </~ keV. To describe the spectrum, we have developed an R-matrix model that accounts for interferences from fermion symmetry and intermediate states, and show these effects to be non-negligible. We also find the spectrum can be described by sequential decay through ℓ=1 states in (5)He, which differs from previous interpretations.

Influence of tegaserod on proximal gastric tone and on the perception of gastric distention in functional dyspepsia

BACKGROUND

Abnormalities in gastric sensorimotor function (hypersensitivity to distention and impaired meal accommodation) have been implicated in the pathophysiology of functional dyspepsia (FD). To study the effect of the 5-HT(4) agonist tegaserod on sensitivity to gastric distention and gastric accommodation in FD.

METHODS

Thirty FD patients (7 males, mean age 42 ± 2 years) underwent a gastric barostat study on two separate occasions, 2 weeks apart, after 5 days of pretreatment with placebo or tegaserod 6 mg b.i.d. in a double-blind randomized order. After introduction of the barostat bag, graded isobaric distentions (2 mmHg increments/2 min) were performed to determine gastric compliance and sensitivity to distention. Subsequently, the pressure level was set at intra-abdominal pressure [minimal distending pressure (MDP)] + 2 mmHg for 90 min, with administration of a liquid meal (200 mL; 300 kcal) after 30 min.

KEY RESULTS

Tegaserod had no influence on MDP (7.9 ± 0.4 vs 7.4 ± 0.4 mmHg) or fasting gastric compliance (44 ± 10 vs 61 ± 6 mL mmHg(-1)) and on fasting thresholds for first perception (3.6 ± 0.4 vs 4.2 ± 0.2 mmHg above MDP) or discomfort (9.9 ± 0.7 vs 10.5 ± 0.5 mmHg above MDP). Tegaserod did not alter intra-balloon volumes before and after the meal [respectively 146 ± 14 vs 120 ± 11 and 297 ± 28 vs 283 ± 29 mL, not significant (NS)], or the amplitude of the meal-induced gastric relaxation (151 ± 23 vs 162 ± 23 mL, NS). In the subgroup with normal gastric emptying (n = 22), tegaserod significantly enhanced meal-induced accommodation (126 ± 23 vs 175 ± 29 mL, ANOVA P < 0.001).

CONCLUSIONS & INFERENCES

Tegaserod does not alter gastric sensorimotor function in FD patients as a group. In the subgroup with normal gastric emptying, tegaserod 6 mg b.i.d enhanced gastric accommodation.

A behavioral analysis of peaking in residential electrical-energy consumers

This study was concerned with "peaking", which is the tendency for electrical-energy users to consume at high rates for brief periods during the day. Peaking results in the inefficient use of generating facilities, which may lead to unfavorable effects on the environment, such as the construction of new energy producing facilities or the activation of older, less safe, generating units. A continuous data collection system to monitor consumption of electrical energy was installed in the homes of three volunteer families. Information, feedback, and incentives were evaluated for their effects on peak energy consumption. A combination of feedback plus incentives was most effective and reduced peaking about 50%. Removal of experimental treatments resulted in a return to pre-treatment patterns of consumption.

Reinforcement and rate of litter depositing

A study was conducted concerning the frequency of litter deposits in a single experimental trash receptacle located in a high-use, urban park setting. There were four two-week periods of alternating no-contingency, contingency conditions during which reinforcement and incentive were evaluated. It was found that reinforcement resulted in the highest rates of behavior and improvements in the aesthetic appearance of the area.

In vitro antibacterial effects of antilipopolysaccharide DNA aptamer-C1qrs complexes

DNA aptamers were developed against lipopolysaccharide (LPS) from E. coli O111:B4 and shown to bind both LPS and E. coli by a colorimetric enzyme-based microplate assay. The polyclonal aptamers were coupled to human C1qrs protein either directly using a bifunctional linker or indirectly using biotinylated aptamers and a streptavidin-C1qrs complex. Both systems significantly reduced colony counts when applied to E. coli O111:B4 and K12 strains across a series of 10x dilutions of the bacteria in the presence of human serum; it was diluted 1: 10(3) in order to avoid significant bacterial lysis by the competing alternate pathway of complement activation. A number of candidate DNA aptamer sequences were cloned and sequenced from the anti-LPS aptamer library for future screening of antibacterial or "antibiotic" potential and to aid in eventual development of an alternative therapy for antibiotic-resistant bacterial infections.

TLR engagement prevents transplantation tolerance

In many experimental models, heart, pancreas and kidney allografts are accepted long-term following costimulation-targeting therapies, whereas skin, lung and intestine resist the induction of tolerance under the same regimens. We noted that a common feature of the resistant organs is their constant exposure to commensal microbes and hypothesized that these microorganisms may stimulate Toll-like receptors (TLRs), promote alloresponses and prevent tolerance induction. This hypothesis prompts the predictions that TLR engagement at the time of transplantation should avert tolerance to heart allografts in animals treated with costimulation-targeting therapies, whereas inhibition of TLR signaling should promote tolerance to skin allografts under the same conditions. Indeed, engagement of a single TLR was sufficient to prevent anti-CD154-mediated long-term cardiac allograft acceptance and correlated with abolished intragraft recruitment of CD4+/FoxP3+ regulatory T cells and the development of linked-suppression. Conversely, a lack of donor and recipient MyD88-dependent signaling led to successful skin allograft acceptance in anti-CD154-treated animals. Thus, the status of TLR signaling contributes to the resistance versus susceptibility of organs to transplantation tolerance.

300 IMMUNO-EXPRESSION OF POTENTIAL FACTORS REGULATING SERTOLI CELL PROLIFERATION IN THE PREPUBERTAL BOAR

Today's pork production is very dependent on reproductive efficiency. Any improvements in the production capability (e.g., number of sperm produced) of the animals involved would be invaluable. Many researchers have examined methods to improve oocyte production, but have not focused on the concentration of sperm produced from a single boar used for artificial insemination (AI). The benefit of using AI is that a greater number of females can be bred to a single boar; thus the total amount of sperm per ejaculation is the main factor in the efficiency of AI. An increase in the number of Sertoli cells leads to an increase in testis size and the number of sperm produced because there are a finite number of germ cells that can be supported by the Sertoli cell during spermatogenesis. Therefore, by examining the factors that control the growth and differentiation of Sertoli cells, the amount of sperm per ejaculation in an individual boar can be increased. The purpose of this research is to begin a systematic analysis of cell cycle regulators expressed in the Sertoli cell during testicular development in the pig. By using pigs of different ages, we will establish a baseline of what regulatory factors are present at different time points in the developing Sertoli cell. Identification of certain factors could lead to an increase in sperm production by enabling the growth of Sertoli cells or inhibition of the natural reduction of these cells. Immunohistochemistry (IHC) analysis was performed on testis tissues from different males (n = 2) at various ages (3, 7, 14, 25, and 50 days) prior to puberty. Tissues were fixed in modified Davidson's fixative, embedded in paraffin, and sectioned; slides were processed for IHC. After antigen retrieval, endogenous hydrogen peroxidase was blocked with 0.6% H2O2 and sections were incubated overnight at 4°C with the appropriate antibody. The following antibodies were used to examine the factors controlling Sertoli cell proliferation: GATA-4 (transcription factor specific for developing and adult pig Sertoli cells), Ki67 (a nuclear protein present in all phases of the cell cycle except G0), cyclin-dependent kinase inhibitor p27 (Kip1), and steroid receptors AR (androgen receptor) and LH2 (estrogen receptor). The slides were then incubated with an appropriate secondary antibody, visualized with DAB chromagen, and counterstained with Mayer's hematoxylin. Immunostaining using p27 (Kip1) revealed no positive staining in any of the days tested, as there is cell division during all of these time points. Protein expression for Ki67 stained mildly after Day 25, suggesting that Sertoli cells became more active at this stage of development. The AR weakly stained and GATA-1 stained intensely at all time points. The data for LH2 were inconclusive and the procedure needs to be performed again. These experiments only give a glimpse of the regulatory factors involved in Sertoli cell proliferation in the developing boar testis. Further studies are being planned to explore other potential factors involved.

Pregnancy outcome in women who use opiates

BACKGROUND

Opiate use in pregnancy is on the increase. There are a number of complications associated with this problem but current data from UK centres are sparse.

DESIGN

A retrospective study.

SETTING

A North of England Hospital.

METHODS

Maternal and neonatal case records were studied and a standard data set completed.

MAIN OUTCOME MEASURES

Maternal and neonatal outcomes were classified by the woman's drug usage at the end of pregnancy.

RESULTS

One hundred and ten babies born to 108 women were studied and 41% had evidence of previous exposure to the hepatitis C virus. Women who took heroin in later pregnancy were significantly more likely than women who were stabilised on methadone to have a baby who needed morphine (40% versus 19%), had higher mean maximum neonatal abstinence scores (NAS) (5.8 versus 4.7) and stayed in the neonatal unit significantly longer (mean 17.2 days versus 11.8 days). There were two neonatal deaths and the overall rate of prematurity was 29%.

CONCLUSIONS

The outcome for pregnancy in women who use opiates is complicated by high rates of prematurity and neonatal death. Women who used heroin in later pregnancy had babies who developed more severe NAS and needed a longer hospital stay than women who used only methadone.

Characterization of protective immunity induced against Schistosoma mansoni via DNA priming with the large subunit of calpain (Sm-p80) in the presence of genetic adjuvants

Despite advances in control via snail eradication and large-scale chemotherapy using praziquental, schistosomiasis continues to spread to new geographic areas particularly in sub-Saharan Africa. Presently, there is no vaccine for controlling this disease. We have concentrated on a functionally important schistosome antigen Sm-p80 as a possible vaccine candidate for schistosomiasis. Here we report the proliferation of spleen cells in response to the recombinant Sm-p80 protein and cytokine (IFN-gamma and IL-4) production by the splenocytes. These spleen cells were obtained from groups of mice that were vaccinated with a DNA vaccine formulation containing Sm-p80 and one of the Th-1 (IL-2 or IL-12) or Th-2 (GM-CSF, IL-4) enhancer cytokines. The splenocytes from the groups of mice vaccinated with Sm-p80 DNA in the presence of Th-2 enhancer cytokines showed moderate but detectable proliferation. The splenocytes obtained from mice vaccinated with Sm-p80 DNA with Th-1 enhancer cytokines IL-2 and IL-12 provided the highest proliferation. The IFN-gamma production by splenocytes was found to follow the similar pattern [(Sm-p80) < (Sm-p80 + IL-4) < (Sm-p80 + GMCSF) < (Sm-p80 + IL-12) < (Sm-p80 + IL-2)], as has been observed for the proliferation and protection data. However, the elevated IL-4 production was inversely correlated to Sm-p80-induced splenocyte proliferation or the protection. These results show again that protective immune response induced by Sm-p80 is of Th-1 type.