Impact of Arbuscular Mycorrhizal Species on Heterodera glycines.

Soybean cyst nematode (SCN, Heterodera glycines) is a widely occurring pest and the leading cause of soybean yield losses in the U.S.A. There is a need to find additional SCN management strategies as sources of SCN resistance have become less effective in managing SCN populations. Arbuscular mycorrhizal fungi (AMF) form symbiotic relationships with roots of most plants including soybean. Research has shown that AMF can reduce disease severity in plants caused by pathogens and pests, including plant parasitic nematodes. The goal of this study was to evaluate the impact of AMF on SCN cyst production, SCN juveniles in roots, and SCN egg hatching. In one experiment, all five AMF species tested (Claroideoglomus claroideum, Diversispora eburnean, Dentiscutata heterogama, Funneliformis mosseae, and Rhizophagus intraradices) reduced (P < 0.05) the number of cysts on soybean roots by 59 to 81%, compared with soybean roots not inoculated with AMF. Inoculation with F. mosseae reduced SCN J2-J3 stage juveniles in soybean roots by 60% at 7 days post inoculation. A separate experiment showed that egg hatch was reduced (P < 0.05) in the presence of F. mosseae spores and their exudates by 27% and 62%, respectively. Further research is needed to evaluate the potential usefulness of AMF in field conditions and to determine the usefulness and potential of the exudates associated with SCN hatching suppression by F. mosseae. Making AMF a more effective biological control agent would provide another management tool to reduce the negative impact of SCN on soybean production.

Evaluation of Soybean for Resistance to Neohyadatothrips variabilis (Thysanoptera: Thripidae) Noninfected and Infected With Soybean Vein Necrosis Virus.

Soybean vein necrosis virus (SVNV) was first identified in Arkansas and Tennessee in 2008 and is now known to be widespread in the United States and Canada. Multiple species of thrips transmit this and other tospoviruses with Neohydatothrips variabilis (Beach) (soybean thrips) cited as the most efficient vector for SVNV. In this study, 18 soybean, Glycine max (L.) Merr., genotypes were evaluated in four experiments by infesting plants with noninfected and SVNV-infected thrips using choice and no-choice assays. In both choice experiments with noninfected and SVNV-infected thrips, the lowest number of immature soybean thrips occurred on plant introductions (PIs) 229358 and 604464 while cultivars Williams 82 and Williamsfield Illini 3590N supported higher counts of mature thrips. The counts between the two assays (noninfected and SVNV-infected thrips) were positively correlated. In both no-choice experiments with noninfected and SVNV-infected thrips, counts of thrips did not differ by soybean genotypes. Further studies are needed to characterize the inheritance and mechanisms involved in the resistance found in the choice assay.

Study of the absorption coefficient of graphene-polymer composites.

In this work, we have prepared a series of polydimethylsiloxane (PDMS) composites containing various graphene flakes loadings (0.02-2 wt%), and their broadband optical properties are being investigated. We demonstrate the tunability and evolution of transmittance and reflection spectra of the composites in a wide spectral range (0.4-200 µm) as a function of graphene content. Using these data we derive the broadband wavelength-dependent absorption coefficient (α) values. Our results show that α is roughly constant in the visible and IR ranges, and, surprisingly, is approximately one order of magnitude lower in the terahertz regime, suggesting different terahertz radiation scattering mechanism in our composite. Our material could be useful for applications in optical communication, sensing or ultrafast photonics.

Comparison of methods applied in photoinduced transient spectroscopy to determining the defect center parameters: The correlation procedure and the signal analysis based on inverse Laplace transformation.

The procedure for determination of trap parameters by photo-induced transient spectroscopy is based on the Arrhenius plot that illustrates a thermal dependence of the emission rate. In this paper, we show that the Arrhenius plot obtained by the correlation method is shifted toward lower temperatures as compared to the one obtained with the inverse Laplace transformation. This shift is caused by the model adequacy error of the correlation method and introduces errors to a calculation procedure of defect center parameters. The effect is exemplified by comparing the results of the determination of trap parameters with both methods based on photocurrent transients for defect centers observed in tin-doped neutron-irradiated silicon crystals and in gallium arsenide grown with the Vertical Gradient Freeze method.

Efficacy and safety of simultaneous vaccination with two modified live virus vaccines against porcine reproductive and respiratory syndrome virus types 1 and 2 in pigs.

The objective of the study was to compare responses of pigs vaccinated with a PRRS MLV vaccine against PRRSV-1 or PRRSV-2 with the responses of pigs vaccinated simultaneously with both vaccines. Furthermore, the efficacy of the two PRRSV MLV vaccination strategies was assessed following challenge. The experimental design included four groups of 4-weeks old SPF-pigs. On day 0 (DPV0), groups 1-3 (N=18 per group) were vaccinated with modified live virus vaccines (MLV) containing PRRSV-1 virus (VAC-T1), PRRSV-2 virus (VAC-T2) or both (VAC-T1T2). One group was left unvaccinated (N=12). On DPV 62, the pigs from groups 1-4 were mingled in new groups and challenged (DPC 0) with PRRSV-1, subtype 1, PRRSV-1, subtype 2 or PRRSV-2. On DPC 13/14 all pigs were necropsied. Samples were collected after vaccination and challenge. PRRSV was detected in all vaccinated pigs and the majority of the pigs were positive until DPV 28, but few of the pigs were still viremic 62 days after vaccination. Virus was detected in nasal swabs until DPV 7-14. No overt clinical signs were observed after challenge. PRRSV-2 vaccination resulted in a clear reduction in viral load in serum after PRRSV-2 challenge, whereas there was limited effect on the viral load in serum following challenge with the PRRSV-1 strains. Vaccination against PRRSV-1 had less impact on viremia following challenge. The protective effects of simultaneous vaccination with PRRSV Type 1 and 2 MLV vaccines and single PRRS MLV vaccination were comparable. None of the vaccines decreased the viral load in the lungs at necropsy. In conclusion, simultaneous vaccination with MLV vaccines containing PRRSV-1 and PRRSV-2 elicited responses comparable to single vaccination and the commercial PRRSV vaccines protected only partially against challenge with heterologous strains. Thus, simultaneous administration of the two vaccines is an option in herds with both PRRSV types.

Effectiveness of immunotherapy in children depends on place of living - A pilot study

BACKGROUND: It is considered that farm areas protect young patients from allergy and asthma due to high exposure to endotoxins. Allergen immunotherapy (AIT) is the only treatment of allergy modifying the immune response with the potential to change the natural history of allergic diseases. It seems that studies evaluating the efficacy of immunotherapy in large cohorts of allergic patients living in farm areas are needed to understand the influence of environment on immune response during AIT. AIM: To compare the clinical effectiveness of immunotherapy between children living in farm versus urban areas. MATERIALS AND METHODS: This was a retrospective analysis of 87 children living in farm area (n=42) and city area (n=45), aged 8-16, who completed three years of subcutaneous immunotherapy due to allergic rhinitis/asthma. An AIT efficacy questionnaire has been designed to be filled in by the allergy specialist during a regular immunotherapy visit before and after AIT. RESULTS: We observed significantly higher improvement in total score among children from farm area compared to children from city area (p < 0.001). Between-group differences in symptoms and drug scores did not reached the level of significance. Multivariate logistic regression analysis (adjustment for the effect of gender and type of allergy) showed that living in farm areas was independently associated with significant improvement in total score after immunotherapy (OR: 10.9; 95%CI: 3.7-32.2). CONCLUSION: The current analysis of the better AIT effectiveness in the farm population has shown the protective influence of environmental exposures on asthma and allergic rhinitis in our children

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Effectiveness of immunotherapy in children depends on place of living - A pilot study.

BACKGROUND: It is considered that farm areas protect young patients from allergy and asthma due to high exposure to endotoxins. Allergen immunotherapy (AIT) is the only treatment of allergy modifying the immune response with the potential to change the natural history of allergic diseases. It seems that studies evaluating the efficacy of immunotherapy in large cohorts of allergic patients living in farm areas are needed to understand the influence of environment on immune response during AIT. AIM: To compare the clinical effectiveness of immunotherapy between children living in farm versus urban areas. MATERIALS AND METHODS: This was a retrospective analysis of 87 children living in farm area (n=42) and city area (n=45), aged 8-16, who completed three years of subcutaneous immunotherapy due to allergic rhinitis/asthma. An AIT efficacy questionnaire has been designed to be filled in by the allergy specialist during a regular immunotherapy visit before and after AIT. RESULTS: We observed significantly higher improvement in total score among children from farm area compared to children from city area (p<0.001). Between-group differences in symptoms and drug scores did not reached the level of significance. Multivariate logistic regression analysis (adjustment for the effect of gender and type of allergy) showed that living in farm areas was independently associated with significant improvement in total score after immunotherapy (OR: 10.9; 95%CI: 3.7-32.2). CONCLUSION: The current analysis of the better AIT effectiveness in the farm population has shown the protective influence of environmental exposures on asthma and allergic rhinitis in our children.

Ghrelin modulates encoding-related brain function without enhancing memory formation in humans.

Ghrelin regulates energy homeostasis in various species and enhances memory in rodent models. In humans, the role of ghrelin in cognitive processes has yet to be characterized. Here we show in a double-blind randomized crossover design that acute administration of ghrelin alters encoding-related brain activity, however does not enhance memory formation in humans. Twenty-one healthy young male participants had to memorize food- and non-food-related words presented on a background of a virtual navigational route while undergoing fMRI recordings. After acute ghrelin administration, we observed decreased post-encoding resting state fMRI connectivity between the caudate nucleus and the insula, amygdala, and orbitofrontal cortex. In addition, brain activity related to subsequent memory performance was modulated by ghrelin. On the next day, however, no differences were found in free word recall or cued location-word association recall between conditions; and ghrelin's effects on brain activity or functional connectivity were unrelated to memory performance. Further, ghrelin had no effect on a cognitive test battery comprising tests for working memory, fluid reasoning, creativity, mental speed, and attention. In conclusion, in contrast to studies with animal models, we did not find any evidence for the potential of ghrelin acting as a short-term cognitive enhancer in humans.

Low-jitter wide-range integrated time interval/delay generator based on combination of period counting and capacitor charging.

We present the design, operation, and test results of a new time interval/delay generator that provides the resolution of 0.3 ps, jitter below 10 ps (rms), and wide delay range of 10 s. The wide range has been achieved by counting periods of a reference clock while the high resolution and low jitter have been obtained through the two-time use of inner interpolation. This interpolation, based on charging of a single capacitor, provides both the precise external trigger synchronization and accurate generation of residual time interval. A combination of both processes virtually eliminates triggering indeterminacy. The jitter between the trigger and output is below 1 ps, which ensures a high performance delay. The generator is integrated in a single application specific integrated circuit chip using a standard cost-effective 0.35 µm CMOS process.

A Cut-Stem Inoculation Technique to Evaluate Soybean for Resistance to Macrophomina phaseolina.

Charcoal rot of soybean is caused by the fungal pathogen Macrophomina phaseolina. Effective and reliable techniques to evaluate soybean for resistance to this fungus are needed to work toward a management scheme that would utilize host resistance. Three experiments were conducted to investigate the use of a cut-stem inoculation technique to evaluate soybean genotypes for resistance to M. phaseolina. The first experiment compared aggressiveness of M. phaseolina isolates collected from soybean on different soybean genotypes. Significant (P < 0.05) differences among the isolates and genotypes for relative area under disease progress curve (RAUDPC) were found without a significant isolate-genotype interaction. The second experiment compared 14 soybean genotypes inoculated with M. phaseolina in multiple trials conducted in two environments, the greenhouse and growth chamber. Significant (P < 0.05) differences among environments and highly significant (P < 0.001) differences among soybean genotypes for RAUDPC were found. The environment-genotype interaction was nonsignificant (P > 0.05). Soybean genotypes DT97-4290, DT98-7553, DT98-17554, and DT99-16864 had significantly (P < 0.05) lower RAUDPC than 7 of the 14 genotypes. The third experiment evaluated resistance in selected Phaseolus spp. and soybean genotypes. The range of RAUDPC for Phaseolus spp. was similar to that of soybean. The Phaseolus lunatus 'Bush Baby Lima' had significantly (P < 0.05) lower RAUDPC than P. vulgaris genotypes evaluated. The cut-stem inoculation technique, which has several advantages over field tests, successfully distinguished differences in aggressiveness among M. phaseolina isolates and relative differences among soybean genotypes for resistance to M. phaseolina comparable with results of field tests.

Plasma glucose after stomach or jejunum glucose infusion in Roux-en-Y gastric bypass patients--a possible implication for early satiety mechanism.

BACKGROUND: Morbidly obese patients undergoing gastric bypass surgery experience early satiety soon after the surgery; the mechanism of this effect is poorly understood. As blood glucose concentration plays a role in appetite regulation in humans, we hypothesized that after gastric bypass surgery glucose absorbed mainly in jejunum leads to a greater rise in plasma glucose that if it is ingested in stomach. MATERIAL AND METHODS: 24 non-diabetes morbidly obese patients (15 women, 9 men, mean age [± SD] 35.6 ± 11.9 years, body weight 140.7 ± 33.1 kg, BMI 46.8 ± 8.3 kg/m²) undergoing Roux-en-Y gastric bypass surgery were given 10 ml of 40% glucose solution to the stomach before its size reduction and to the jejunum after gastro-jejunal anastomosis was formed. RESULTS: After jejunal infusion blood glucose increased more rapidly and was ∼30% higher than after stomach infusion. Moreover, this increase was less pronounced in more obese patients. CONCLUSION: In patients after Roux-en-Y gastric bypass surgery glucose absorbed in jejunum leads to greater rise in plasma glucose concentration than if it is ingested in stomach. This phenomenon may help explain satiety feeling occurring early in gastric bypass surgery patients.

Decreasing concentration of interstitial glucose in REM sleep in subjects with normal glucose tolerance.

AIMS: Sleep is divided into two major stages, non-rapid eye movement (NREM) and rapid eye movement (REM), which are distinct in various neuroendocrine respects. NREM/REM cycles influence insulin and glucagon secretion; however, glucose concentrations in REM compared with NREM have not been directly explored. The aim was to investigate the differences in glucose concentrations in interstitial fluid (IGC) between NREM/REM cycles using a continuous glucose monitoring system (CGMS). METHODS: Thirteen subjects were eligible for analysis out of the 28 enrolled. All underwent standard polysomnography for the assessment of sleep stages and the exclusion of sleep apnoea syndrome with CGMS and subsequent morning oral glucose tolerance test (exclusion of glucose intolerance or diabetes). RESULTS: The IGC in REM fell in 12 out of the 13 subjects, whereas the IGC in NREM increased in eight out of the 13 subjects. Therefore, the mean change of IGC differed in direction between sleep stages: -0.028 (-0.045 to -0.011) for REM vs. 0.005 (-0.012 to 0.017) for NREM [median (QR), P = 0.007, n = 13], with the mean difference of 0.038 mmol/l x 5 min(-1) (95% confidence interval 0.012, 0.064). The mean glucose concentration in REM sleep was lower than in NREM: 4.29 +/- 1.00 vs. 4.53 +/- 0.90 mmol/l (mean +/- sd, P = 0.003, n = 13). CONCLUSIONS: The decrease in IGC in REM compared with NREM sleep, with lower absolute values, may arise from different physiological events observed in these sleep stages. The REM-related decline in glucose concentrations may be a risk factor for nighttime hypoglycaemia.

Spectral behavior of thin film coated cascaded tapered long period gratings in multiple configurations.

In this work the spectral response of cascaded tapered long period gratings coated by nano-sized polymeric films has been investigated as function of the surrounding medium refractive index (SRI). The investigation was aimed to identify the best configuration in terms of coated/not coated areas in order to fully benefit of the SRI sensitivity enhancement due to the modal transition mechanism of nano-coated long period gratings while preserving the fringes visibility.

G/A polymorphism at -258 of the hepatic glucokinase promoter is not associated with decreased birth weight in preterm neonates.

BACKGROUND: A high percentage of preterm neonates are born small for gestational age (SGA). These children show a high morbidity and mortality after birth and often develop insulin resistance with ensuing impaired glucose metabolism in adulthood. Since insulin is important for intrauterine growth, fetal insulin resistance might also influence birth weight of preterm neonates. OBJECTIVES: A common polymorphism in the promoter region of the human hepatic glucokinase (-258) is associated with a decreased promoter activity, an enhanced insulin secretion, and hypertension and hepatic insulin resistance in adults. In this pilot study we wanted to investigate whether the G/A polymorphism at -258 of the hepatic glucokinase promoter has an effect on birth weight of preterm neonates and therefore might constitute a genotype leading to low birth weight and metabolic defects. METHODS: We enrolled 106 preterm neonates in our study. 44 of them were SGA and 62 AGA neonates. We extracted DNA from a buccal swab and identified the polymorphism by PCR-ARMS. RESULTS: We found no difference in the prevalence of the polymorphism in either groups. CONCLUSION: The polymorphism at -258 of the fetal hepatic glucokinase promoter is most probably not of a major relevance in the pathophysiology of low birth weight in preterm neonates.

Ferromagnetic spins interaction in poly(m-p-aniline).

Alternating poly(m-p-aniline) can be oxidized to radical cations with spins S = 1/2. For high spin density, ferromagnetic spin interaction is observed, and some of the generated radical cations are found to be in a ground triplet state.

Distribution of the components of the NCEP ATP III-defined metabolic syndrome in newly diagnosed diabetes and non-diabetes caucasian subjects; implications for metabolic syndrome prevention and treatment.

UNLABELLED: The study aimed at assessing the relationship between five components of the NCEP ATP III-defined metabolic syndrome (MS) in diabetes and non-diabetes MS subjects. METHODS: Prevalence of MS and its components was assessed in 1586 adult Caucasian individuals, without known diabetes. Oral glucose tolerance test (OGTT) with 75 g glucose according to WHO protocol was conducted in all subjects. RESULTS: MS was diagnosed in 419 persons (prevalence 26.4%), including 123 subjects with newly diagnosed diabetes. Diabetes subjects presented with higher plasma triglycerides and slightly more pronounced abdominal obesity as well as higher fasting plasma insulin, which in all reflected insulin resistance-related character of MS pathophysiology. However, the distribution of MS components was largely uneven in diabetes and non-diabetes subjects. Elevated plasma triglycerides and low HDL cholesterol were the most prevalent components. The least often found component was elevated fasting plasma glucose (FPG). Non-diabetes subjects with elevated FPG were more likely to present with three or four other components than with two of them only. In contrast, those with high plasma triglycerides, low plasma HDL cholesterol or increased waist circumference were all more likely to have two rather than three or four other MS components. Subjects with diabetes presented significantly more often with four or five MS components when compared with non-diabetes subjects. CONCLUSIONS: The components of metabolic syndrome are not equally prevalent in Caucasian population. Lipid disorders are most often found and glucose intolerance is the least prevalent MS component. Glucose intolerance and diabetes occurred in a more complex setting, concomitantly with three or four other MS components, suggesting that diabetes is associated with more advanced stages of MS. These findings may have important implications for MS prevention and treatment.

[Retropharyngeal tendinitis. Differential diagnosis in the management of acute neck pain]. / Retropharyngeale Tendinitis. Differenzialdiagnose des akuten Zervikalsyndroms.

Neck pain is frequent and can be a symptom of numerous differential diagnoses with quite different diagnostic and therapeutic consequences. A 37-year-old woman reported acute neck pain aggravated by movements of the cervical spine and head and by swallowing. Clinical examination showed pronounced neck stiffness. T2-weighted MRI demonstrated high-intensity edema and effusion localized prevertebrally in the area of the superior part of the longus colli muscle. Computed tomography of this region demonstrated prevertebral calcification leading to the diagnosis of retropharyngeal tendinitis. Nonsteroidal antiphlogistic drugs led to rapid improvement of clinical signs and symptoms. Retropharyngeal tendinitis should be considered in patients with acute neck pain.