Protein metabolism in leg muscle following an endotoxin injection in healthy volunteers

A B S T R A C T The human endotoxin model has been used to study the early phase of sepsis. The aim of the present study was to assess leg muscle protein kinetics after an endotoxin challenge given to healthy human volunteers. Six healthy male subjects were studied in the post-absorptive state before and during 4 h following an intravenous endotoxin bolus (4 ng/kg of body weight). Primed continuous infusion of [ 2 H 5 ]phenylalanine and [ 2 H 3 ]3-methylhistidine in combination with sampling from the radial artery, femoral vein and muscle tissue were used to assess leg muscle protein kinetics. Both two-and three-compartment models were used to calculate protein kinetics. In addition 26S proteasome activity and protein ubiquitination were assessed. An increase in the net release of phenylalanine from the leg following the endotoxin challenge was observed; however, this phenylalanine originates from the free intracellular pool and not from protein. Net protein balance was unchanged, whereas both protein synthesis and breakdown were decreased. Degradation rates of contractile proteins were not affected by endotoxin, as indicated by an unchanged rate of appearance of 3-methylhistidine from leg muscle. In addition, proteasome activity and protein ubiquitination were unaffected by endotoxaemia. In conclusion, intravenous endotoxin administration to healthy volunteers resulted in an increased release of free phenylalanine from skeletal muscle, whereas protein balance was unaffected. Both protein synthesis and breakdown were decreased to a similar extent

Correlated conformation and charge transport in multiwall carbon nanotube - conducting polymer nanocomposites

The strikingly different charge transport behaviors in nanocomposites of multiwall carbon nanotubes (MWNTs) and conducting polymer polyethylene dioxythiophene - polystyrene sulfonic acid (PEDOT-PSS) at low temperatures are explained by probing their conformational properties using small angle X-ray scattering (SAXS). The SAXS studies indicate assembly of elongated PEDOT-PSS globules on the walls of nanotubes, coating them partially thereby limiting the interaction between the nanotubes in the polymer matrix. This results in a charge transport governed mainly by small polarons in the conducting polymer despite the presence of metallic MWNTs. At T > 4 K, hopping of the charge carriers following 1D-VRH is evident which also gives rise to a positive magnetoresistance (MR) with an enhanced localization length (~ 5 nm) due to the presence of MWNTs. However, at T < 4 K, the observation of an unconventional positive temperature coefficient of resistivity (TCR) is attributed to small polaron tunnelling. The exceptionally large negative MR observed in this temperature regime is conjectured to be due to the presence of quasi-1D MWNTs that can aid in lowering the tunnelling barrier across the nanotube - polymer boundary resulting in large delocalization.Comment: Accepted J. Phys.: Condens. Matte

Feasibility of using smart phones to estimate chlorophyll content in corn plants

New spectral absorption photometry methods are introduced to estimate chlorophyll (Chl) content of corn leaves by smart phones. The first method acquires light passing through a leaf by smartphone camera, compensating for differences in illumination conditions. In order to improve performance of the method, spectral absorption photometry (SAP) with background illumination has been considered as well. Data were acquired by smartphone camera in Iowa State University maize fields. Various indices were extracted and their correlation with Chl content were examined by Minolta SPAD-502. Hue index in SAP reached R ² value of 0.59. However, with light-aided SAP (LASAP), R ² of 0.97 was obtained. Among traits, the vegetation index gave the most accurate indication. We can conclude that the high performance of LASAP method for estimating Chl content, leads to new opportunities offered by smart phones at much lower cost. This is a highly accurate alternative to SPAD meters for estimating Chl content nondestructively.This article is published as Vesali, F., M. Omid, H. Mobli, and A. Kaleita. "Feasibility of using smart phones to estimate chlorophyll content in corn plants." Photosynthetica 55, no. 4 (2017): 603-610. DOI: 10.1007/s11099-016-0677-9. Posted with permission.</p

Feasibility of using smart phones to estimate chlorophyll content in corn plants

New spectral absorption photometry methods are introduced to estimate chlorophyll (Chl) content of corn leaves by smart phones. The first method acquires light passing through a leaf by smartphone camera, compensating for differences in illumination conditions. In order to improve performance of the method, spectral absorption photometry (SAP) with background illumination has been considered as well. Data were acquired by smartphone camera in Iowa State University maize fields. Various indices were extracted and their correlation with Chl content were examined by Minolta SPAD-502. Hue index in SAP reached R ² value of 0.59. However, with light-aided SAP (LASAP), R ² of 0.97 was obtained. Among traits, the vegetation index gave the most accurate indication. We can conclude that the high performance of LASAP method for estimating Chl content, leads to new opportunities offered by smart phones at much lower cost. This is a highly accurate alternative to SPAD meters for estimating Chl content nondestructively.This article is published as Vesali, F., M. Omid, H. Mobli, and A. Kaleita. "Feasibility of using smart phones to estimate chlorophyll content in corn plants." Photosynthetica 55, no. 4 (2017): 603-610. DOI: 10.1007/s11099-016-0677-9. Posted with permission.</p

Reserve of strength in reinforced concrete frames : analysis of arching action

Compressive membrane (arching) action increases both the capacity and stiffness of longitudinally-restrained reinforced concrete elements; however, contribution of arching action in the loading capacity of reinforced concrete beams within framed structures has not been investigated. In this study, the formulation of a non-linear 1D finite element model is briefly explained and then verified against available experimental data. The developed formulation and analytical tool are employed to undertake a parametric study and effects of compressive strength of concrete, longitudinal reinforcing ratio, stiffness of end supports and number of spans on the ultimate capacity of beams within different types of reinforced concrete assemblages is investigated. For the analysed 2D sub-assemblies, the capacity of the beams calculated from plastic hinge analysis (according to AS3600-2009) is more than 15% below the capacity obtained from non-linear 1D finite element model and this is partially attributed to enhancing effect of arching action which cannot be captured by the model adopted in Australian standard AS3600-2009

Effect of Breastfeeding in Early Life on Cardiorespiratory and Physical Fitness: A Systematic Review and Meta-Analysis

Background: Numerous studies have reported the associations between the type of feeding during infancy and subsequent chronic diseases. Objective: The objective of this systematic review is to synthesize the available literature concerning the effect of breastfeeding in infancy on physical and cardiorespiratory fitness in children and adolescents. Materials and Methods: We performed a comprehensive search of medical bibliographic databases to identify observational studies reporting the association between breastfeeding and cardiorespiratory or physical fitness. Random effects model was used for calculating the pooled estimates. Results: Three studies with 2,792 children were included in the meta-analysis. The mean value of VO2max was similar between formula-fed and 1-3 months breastfed participants (standardized mean difference SMD: 0.1, 95% confidence intervals CI: -0.09 to 0.29, p = 0.31). There was no difference between 3 and 6 months breastfed (SMD: 0.17, 95% CI: -0.01 to 0.35, p = 0.06), &gt;6 months breastfed (SMD: 0.37, 95% CI: -0.03 to 0.78, p = 0.07), and formula-fed children. The pooled SMD in handgrip strength was 0.09 (95% CI: -0.04 to 0.23; p = 0.17) between 1 and 3 months breastfed and formula-fed children .Nevertheless, 3-6 months (SMD: 0.13; 95% CI: 0.03-0.24) and &gt;6 months (SMD: 0.19; 95% CI: 0.01-0.37) breastfeeding was associated with higher handgrip strength compared with formula-fed children. Breastfeeding for 1-3 (SMD: 0.20; 95% CI: 0.12-0.28), 3-6 (SMD: 0.27; 95% CI: 0.18-0.37), and &gt;6 months (SMD: 0.34; 95% CI: 0.11-0.58) led to a significantly higher standing long-jump performance compared with formula feeding. Conclusions: Breastfeeding shows beneficial effects on physical fitness, but further well-designed studies need to clarify effects of breastfeeding on cardiorespiratory fitness. © Copyright 2018, Mary Ann Liebert, Inc

Effect of Breastfeeding in Early Life on Cardiorespiratory and Physical Fitness: A Systematic Review and Meta-Analysis

Background: Numerous studies have reported the associations between the type of feeding during infancy and subsequent chronic diseases. Objective: The objective of this systematic review is to synthesize the available literature concerning the effect of breastfeeding in infancy on physical and cardiorespiratory fitness in children and adolescents. Materials and Methods: We performed a comprehensive search of medical bibliographic databases to identify observational studies reporting the association between breastfeeding and cardiorespiratory or physical fitness. Random effects model was used for calculating the pooled estimates. Results: Three studies with 2,792 children were included in the meta-analysis. The mean value of VO2max was similar between formula-fed and 1-3 months breastfed participants (standardized mean difference SMD: 0.1, 95% confidence intervals CI: -0.09 to 0.29, p = 0.31). There was no difference between 3 and 6 months breastfed (SMD: 0.17, 95% CI: -0.01 to 0.35, p = 0.06), &gt;6 months breastfed (SMD: 0.37, 95% CI: -0.03 to 0.78, p = 0.07), and formula-fed children. The pooled SMD in handgrip strength was 0.09 (95% CI: -0.04 to 0.23; p = 0.17) between 1 and 3 months breastfed and formula-fed children .Nevertheless, 3-6 months (SMD: 0.13; 95% CI: 0.03-0.24) and &gt;6 months (SMD: 0.19; 95% CI: 0.01-0.37) breastfeeding was associated with higher handgrip strength compared with formula-fed children. Breastfeeding for 1-3 (SMD: 0.20; 95% CI: 0.12-0.28), 3-6 (SMD: 0.27; 95% CI: 0.18-0.37), and &gt;6 months (SMD: 0.34; 95% CI: 0.11-0.58) led to a significantly higher standing long-jump performance compared with formula feeding. Conclusions: Breastfeeding shows beneficial effects on physical fitness, but further well-designed studies need to clarify effects of breastfeeding on cardiorespiratory fitness. © Copyright 2018, Mary Ann Liebert, Inc