Nuevo registro de Brontocoris tabidus (Hemiptera: Pentatomidae) atacando larvas de Heteroperreyia hubrichi (Hymenoptera: Pergidae)

Schinus terebinthifolia Raddi (Anacardiaceae) es un árbol perenne nativo de Argentina, Brasil, Paraguay y Uruguay, considerado actualmente una de las especies invasoras más agresivas y extendidas en Florida, Hawai y Texas (Estados Unidos). La avispa sierra defoliadora, Heteroperreyia hubrichi Malaise (Hymenoptera: Pergidae), es un agente potencial de control biológico para S. terebinthifolia. Durante inspecciones de campo recientes en el área de distribución nativa de S. terebinthifolia, ninfas y adultos de Brontocoris tabidus (Signoret) (Hemiptera: Pentatomidae) fueron encontrados predando larvas de H. hubrichi y Heteroperreyia n.? sp. sobre plantas de S. terebinthifolia en Argentina (Provincia de Misiones) y Brasil (Estado de Rio Grande do Sul) respectivamente. La depredación de B. tabidus sobre larvas de especies de Heteroperreyia constituye nuevos registros.Brazilian peppertree (Schinus terebinthifolia Raddi; Anacardiaceae) is a perennial tree native to Argentina, Brazil, Paraguay and Uruguay. Brazilian peppertree is one of the most aggressive and widespread invasive species in Florida, Hawaii, and Texas (USA). The defoliating sawfly, Heteroperreyia hubrichi Malaise (Hymenoptera: Pergidae), is a potential biological control agent for S. terebinthifolia. During surveys of plant use under natural conditions in the S. terebinthifolia native range, nymphs and adults of Brontocoris tabidus (Signoret) (Hemiptera: Pentatomidae) were found attacking H. hubrichi and Heteroperreyia n.? sp. larvae feeding on S. terebinthifolia in Argentina (Misiones Province) and Brazil (Rio Grande do Sul) respectively. The attack by B. tabidus on Heteroperreyia species constitutes new records.Fil: Mc Kay, Fernando. Fundación para el Estudio de Especies Invasivas; ArgentinaFil: Dellapé, Gimena. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Dyer, Kisten. United States Department of Agriculture; Estados UnidosFil: Wheeler, Gregory. United States Department of Agriculture; Estados Unido

MRI Acquisition and Analysis Protocol for In Vivo Intraorbital Optic Nerve Segmentation at 3T

Purpose.: To present a new acquisition and analysis protocol for reliable and reproducible segmentation of the entire intraorbital optic nerve (ION) mean cross-sectional area by means of magnetic resonance imaging (MRI) at 3 tesla (T). / Methods.: Eight healthy volunteers (mean age 31, five were male) gave written informed consent and both of their IONs were imaged individually using a coronal-oblique T2-weighted fast multidynamic image acquisition scheme; the proposed acquisition scheme has its rationale in combining separately acquired volumes and registering them to account for motion-related artifacts commonly associated with longer acquisitions. Mean cross-sectional area of each ION was measured using a semiautomated image analysis protocol that was based on an active surface model previously described and used for spinal cord imaging. Reproducibility was assessed for repeated scans (scan-rescan) and repeated image analysis performance (intraobserver). / Results.: Mean and SD values of the left ION cross-sectional area for the eight healthy volunteers were 5.0 (±0.7) mm2 and for the right ION were 5.3 (±0.8) mm2. Mean scan-rescan coefficient of variation (COV) for the left ION was 4.3% and for the right was 4.4%. Mean intraobserver COV for the left ION was 2.1% and for the right was 1.8%. / Conclusions.: This study presents a new MRI acquisition and analysis protocol for reliable and reproducible in vivo measurement of the entire ION mean cross-sectional area as demonstrated in a pilot study of healthy subjects. The protocol presented here can be used in future studies of the ION in disease state

Grey and White Matter Magnetisation Transfer Ratio Measurements in the Lumbosacral Enlargement: A Pilot In Vivo Study at 3T

Magnetisation transfer (MT) imaging of the central nervous system has provided further insight into the pathophysiology of neurological disease. However, the use of this method to study the lower spinal cord has been technically challenging, despite the important role of this region, not only for motor control of the lower limbs, but also for the neural control of lower urinary tract, sexual and bowel functions. In this study, the feasibility of obtaining reliable grey matter (GM) and white matter (WM) magnetisation transfer ratio (MTR) measurements within the lumbosacral enlargement (LSE) was investigated in ten healthy volunteers using a clinical 3T MRI system. The mean cross-sectional area of the LSE (LSE-CSA) and the mean GM area (LSE-GM-CSA) were first obtained by means of image segmentation and tissue-specific (i.e. WM and GM) MTR measurements within the LSE were subsequently obtained. The reproducibility of the segmentation method and MTR measurements was assessed from repeated measurements and their % coefficient of variation (%COV). Mean (± SD) LSE-CSA across 10 healthy subjects was 59.3 (± 8.4) mm2 and LSE-GM-CSA was 17.0 (± 3.1) mm2. The mean intra- and inter-rater % COV for measuring the LSE-CSA were 0.8% and 2.3%, respectively and for the LSE-GM-CSA were 3.8% and 5.4%, respectively. Mean (± SD) WM-MTR was 43.2 (± 4.4) and GM-MTR was 40.9 (± 4.3). The mean scan-rescan % COV for measuring WM-MTR was 4.6% and for GM-MTR was 3.8%. Using a paired t-test, a statistically significant difference was identified between WM-MTR and GM-MTR in the LSE (p<0.0001). This pilot study has shown that it is possible to obtain reliable tissue-specific MTR measurements within the LSE using a clinical MR system at 3T. The MTR acquisition and analysis protocol presented in this study can be used in future investigations of intrinsic spinal cord diseases that affect the LSE

The impact of the Southern Annular Mode on future changes in Southern Hemisphere rainfall

A robust positive trend in the Southern Annular Mode (SAM) is projected for the end of the 21st century under the Representative Concentration Pathway 8.5 scenario, which results in rainfall decreases in the midlatitudes and increases in the high latitudes in the Southern Hemisphere (SH). We find that this SAM trend also increases rainfall over the SH subtropics in austral summer but not in winter, leading to a pronounced wintertime poleward expansion of the subtropical dry zone. These dynamically driven rainfall changes by the SAM appear to oppose the thermodynamically driven projected rainfall changes in the SH subtropics and midlatitudes, whereas the two components reinforce each other in the high latitudes. However, we show that most climate models fall short in capturing the observed SAM component driven by the El Nino-Southern Oscillation and associated rainfall in the austral warm seasons, which limits our confidence in quantifying the contribution of the SAM to projected rainfall changes.11145Ysciescopu

ADvanced IMage Algebra (ADIMA): a novel method for depicting multiple sclerosis lesion heterogeneity, as demonstrated by quantitative MRI.

There are modest correlations between multiple sclerosis (MS) disability and white matter lesion (WML) volumes, as measured by T2-weighted (T2w) magnetic resonance imaging (MRI) scans (T2-WML). This may partly reflect pathological heterogeneity in WMLs, which is not apparent on T2w scans

Characterising hyperinsulinaemia induced insulin resistance in human skeletal muscle cells

Hyperinsulinaemia potentially contributes to insulin resistance in metabolic tissues, such as skeletal muscle. The purpose of these experiments was to characterise glucose uptake, insulin signalling and relevant gene expression in primary human skeletal muscle-derived cells (HMDCs), in response to prolonged insulin exposure (PIE) as a model of hyperinsulinaemia-induced insulin resistance. Differentiated HMDCs from healthy human donors were cultured with or without insulin (100 nM) for 3 days followed by an acute insulin stimulation. HMDCs exposed to PIE were characterised by impaired insulin-stimulated glucose uptake, blunted IRS-1 phosphorylation (Tyr612) and Akt (Ser473) phosphorylation in response to an acute insulin stimulation. Glucose transporter 1 (GLUT1), but not GLUT4, mRNA and protein increased following PIE. The mRNA expression of metabolic (PDK4) and inflammatory markers (TNF-α) was reduced by PIE but did not change lipid (SREBP1 and CD36) or mitochondrial (UCP3) markers. These experiments provide further characterisation of the effects of PIE as a model of hyperinsulinaemia-induced insulin resistance in HMDCs

Fast and reproducible in vivo T1 mapping of the human cervical spinal cord

PURPOSE: To develop a fast and robust method for measuring T1 in the whole cervical spinal cord in vivo, and to assess its reproducibility. METHODS: A spatially nonselective adiabatic inversion pulse is combined with zonally oblique-magnified multislice echo-planar imaging to produce a reduced field-of-view inversion-recovery echo-planar imaging protocol. Multi- inversion time data are obtained by cycling slice order throughout sequence repetitions. Measurement of T1 is performed using 12 inversion times for a total protocol duration of 7 min. Reproducibility of regional T1 estimates is assessed in a scan-rescan experiment on five heathy subjects. RESULTS: Regional mean (standard deviation) T1 was: 1108.5 (±77.2) ms for left lateral column, 1110.1 (±83.2) ms for right lateral column, 1150.4 (±102.6) ms for dorsal column, and 1136.4 (±90.8) ms for gray matter. Regional T1 estimates showed good correlation between sessions (Pearson correlation coefficient = 0.89 (P value < 0.01); mean difference = 2 ms, 95% confidence interval ± 20 ms); and high reproducibility (intersession coefficient of variation approximately 1% in all the regions considered, intraclass correlation coefficient = 0.88 (P value < 0.01, confidence interval 0.71-0.95)). CONCLUSIONS: T1 estimates in the cervical spinal cord are reproducible using inversion-recovery zonally oblique-magnified multislice echo-planar imaging. The short acquisition time and large coverage of this method paves the way for accurate T1 mapping for various spinal cord pathologies. Magn Reson Med, 2017. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited

Feasibility of in vivo multi-parametric quantitative magnetic resonance imaging of the healthy sciatic nerve with a unified signal readout protocol

Magnetic resonance neurography (MRN) has been used successfully over the years to investigate the peripheral nervous system (PNS) because it allows early detection and precise localisation of neural tissue damage. However, studies demonstrating the feasibility of combining MRN with multi-parametric quantitative magnetic resonance imaging (qMRI) methods, which provide more specific information related to nerve tissue composition and microstructural organisation, can be invaluable. The translation of emerging qMRI methods previously validated in the central nervous system to the PNS offers real potential to characterise in patients in vivo the underlying pathophysiological mechanisms involved in a plethora of conditions of the PNS. The aim of this study was to assess the feasibility of combining MRN with qMRI to measure diffusion, magnetisation transfer and relaxation properties of the healthy sciatic nerve in vivo using a unified signal readout protocol. The reproducibility of the multi-parametric qMRI protocol as well as normative qMRI measures in the healthy sciatic nerve are reported. The findings presented herein pave the way to the practical implementation of joint MRN-qMRI in future studies of pathological conditions affecting the PNS

Mitochondrial phylogeography and demographic history of the Vicuña: implications for conservation

The vicuña (Vicugna vicugna; Miller, 1924) is a conservation success story, having recovered from near extinction in the 1960s to current population levels estimated at 275 000. However, lack of information about its demographic history and genetic diversity has limited both our understanding of its recovery and the development of science-based conservation measures. To examine the evolution and recent demographic history of the vicuña across its current range and to assess its genetic variation and population structure, we sequenced mitochondrial DNA from the control region (CR) for 261 individuals from 29 populations across Peru, Chile and Argentina. Our results suggest that populations currently designated as Vicugna vicugna vicugna and Vicugna vicugna mensalis comprise separate mitochondrial lineages. The current population distribution appears to be the result of a recent demographic expansion associated with the last major glacial event of the Pleistocene in the northern (18 to 22°S) dry Andes 14–12 000 years ago and the establishment of an extremely arid belt known as the 'Dry Diagonal' to 29°S. Within the Dry Diagonal, small populations of V. v. vicugna appear to have survived showing the genetic signature of demographic isolation, whereas to the north V. v. mensalis populations underwent a rapid demographic expansion before recent anthropogenic impacts

The VITAH Trial-Vitamin D Supplementation and Cardiac Autonomic Tone in Patients with End-Stage Kidney Disease on Hemodialysis: A Blinded, Randomized Controlled Trial

End-stage kidney disease (ESKD) patients are at increased cardiovascular risk. Vitamin D deficiency is associated with depressed heart rate variability (HRV), a risk factor depicting poor cardiac autonomic tone and risk of cardiovascular death. Vitamin D deficiency and depressed HRV are highly prevalent in the ESKD population. We aimed to determine the effects of oral vitamin D supplementation on HRV ((low frequency (LF) to high frequency (HF) spectral ratio (LF:HF)) in ESKD patients on hemodialysis. Fifty-six subjects with ESKD requiring hemodialysis were recruited from January 2013-March 2015 and randomized 1:1 to either conventional (0.25 mcg alfacalcidol plus placebo 3×/week) or intensive (0.25 mcg alfacalcidol 3×/week plus 50,000 international units (IU) ergocalciferol 1×/week) vitamin D for six weeks. The primary outcome was the change in LF:HF. There was no difference in LF:HF from baseline to six weeks for either vitamin D treatment (conventional: p = 0.9 vs. baseline; intensive: p = 0.07 vs. baseline). However, participants who remained vitamin D-deficient (25-hydroxyvitamin D < 20 ng/mL) after treatment demonstrated an increase in LF:HF (conventional: n = 13, ∆LF:HF: 0.20 ± 0.06, p < 0.001 vs. insufficient and sufficient vitamin D groups; intensive: n = 8: ∆LF:HF: 0.15 ± 0.06, p < 0.001 vs. sufficient vitamin D group). Overall, six weeks of conventional or intensive vitamin D only augmented LF:HF in ESKD subjects who remained vitamin D-deficient after treatment. Our findings potentially suggest that while activated vitamin D, with or without additional nutritional vitamin D, does not appear to improve cardiac autonomic tone in hemodialysis patients with insufficient or sufficient baseline vitamin D levels, supplementation in patients with severe vitamin D deficiency may improve cardiac autonomic tone in this higher risk sub-population of ESKD. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01774812