Prevention of enteroxigenic Escherichia coli infections in pigs by dairy-based nutrition

Abstract Postweaning diarrhea (PWD) is a significant enteric disease causing considerable economic losses for the pig industry. Among several aetiological risk factors, enterotoxigenic Escherichia coli (ETEC) is considered to be a major cause. After being routinely used for several decades to control bacterial disease outbreaks in piglet, the use of antibiotics at subtherapeutic concentrations has been banned in the European Union because of the increasing prevalence of resistance to antibiotics in pigs. The removal of in-feed antibiotics from piglet diets has negative economic consequences as it dramatically increases the rate of morbidity and mortality due to ETEC as well as the use of antibiotics for therapeutic purposes. Other than subtherapeutic antibiotics, zinc oxide (ZnO) had been reported to ameliorate and/or prevent the development of PWD in piglets, but its excretion may have negative impacts on the environment. Thus, other alternatives that control ETEC infections in piglets postweaning will be of great advantage. A number of nutritional strategies have been proposed as alternative means of preventing ETEC infections, of which feeding dairy-based products to piglets could be one of such strategies. It is apparent that colostrums, milk and milk fractions such as whey and casein contain several biologically active compounds with anti-microbial and immunomodulatory properties. Recently, these dairy products and their isolated compounds such as lactoferrin and oligosaccharides have been employed as anti-infective agents against ETEC infections in iglets postweaning. The dairy by-products (e.g. whey or whey permeate) may also be fermented to further improve the anti-infective potential of the products. Overall, the anti-infective activities of dairy-based products against ETEC could be attributed to the improvement of the intestinal barrier functions, microbial ecosystem and immunity of the piglets. Keywords : Dairy-based product; Anti-microbial; Immunomodulation; Anti-infective; Enterotoxigenic Escherichia coli; Postweaning diarrhea; Pigle

Passive phloem loading and long-distance transport in a synthetic tree-on-a-chip

Vascular plants rely on differences of osmotic pressure to export sugars from regions of synthesis (mature leaves) to sugar sinks (roots, fruits). In this process, known as M\"unch pressure flow, the loading of sugars from photosynthetic cells to the export conduit (the phloem) is crucial, as it sets the pressure head necessary to power long-distance transport. Whereas most herbaceous plants use active mechanisms to increase phloem concentration above that of the photosynthetic cells, in most tree species, for which transport distances are largest, loading seems to occur via passive symplastic diffusion from the mesophyll to the phloem. Here, we use a synthetic microfluidic model of a passive loader to explore the nonlinear dynamics that arise during export and determine the ability of passive loading to drive long-distance transport. We first demonstrate that in our device, phloem concentration is set by the balance between the resistances to diffusive loading from the source and convective export through the phloem. Convection-limited export corresponds to classical models of M\"unch transport, where phloem concentration is close to that of the source; in contrast, diffusion-limited export leads to small phloem concentrations and weak scaling of flow rates with the hydraulic resistance. We then show that the effective regime of convection-limited export is predominant in plants with large transport resistances and low xylem pressures. Moreover, hydrostatic pressures developed in our synthetic passive loader can reach botanically relevant values as high as 10 bars. We conclude that passive loading is sufficient to drive long-distance transport in large plants, and that trees are well suited to take full advantage of passive phloem loading strategies

Pain-related beliefs among Chinese patients with chronic pain: The construct and concurrent predictive validity of the Chinese version of the survey of pain attitudes-14 (ChSOPA-14)

Context: Pain beliefs as indexed by the Survey of Pain Attitudes (SOPA) have been consistently shown to predict pain adjustment outcomes in Western populations. However, its utility in non-Western populations is unclear. Objectives: We evaluated the construct and predictive validity of the Chinese version of the 14-item SOPA (ChSOPA-14) in a sample of Chinese patients with chronic pain. Methods: A total of 208 Chinese patients with chronic musculoskeletal pain completed the ChSOPA-14, the Chronic Pain Grade questionnaire, the Pain Catastrophizing Scale, the Center for Epidemiological Studies-Depression Scale, and measures of sociodemographic characteristics. Results: Except Medical Cure, all ChSOPA-14 scales were significantly correlated with validity criterion measures (all P < 0.05) in expected directions. The present Chinese sample scored the highest on the Medical Cure scale (mean = 2.98, standard deviation [SD] = 1.05) but the lowest on the Disability scale (mean = 1.75, SD = 1.67). Results of hierarchical multiple regression analyses showed that the ChSOPA-14 scales predicted concurrent depression (F(7,177) = 14.51, P < 0.001) and pain disability (F(7,180) = 8.77, P < 0.001). Pain Control (stdβ [standardized beta coefficient] = -0.13; 95% confidence interval [CI]: -3.41, -0.13; P < 0.05) and Emotion (stdβ = 29; 95% CI: 1.76, 5.02; P < 0.001) emerged as significant independent predictors of concurrent depression whereas Disability (stdβ = 0.19; 95% CI: 1.33, 7.88; P < 0.01), Emotion (stdβ = 16; 95% CI: 0.08, 7.59; P < 0.05), and Solicitude (stdβ = -0.14; 95% CI: -7.05, -0.04; P < 0.05) significantly associated with concurrent disability. Conclusion: The findings offer preliminary evidence for the construct and concurrent predictive validity of the ChSOPA-14. This makes available a suitable instrument for chronic pain in the Chinese population and will facilitate future cross-cultural research on pain beliefs. © 2011 U.S. Cancer Pain Relief Committee Published by Elsevier Inc. All rights reserved.postprin

Preliminary Psychometric Properties of the Chinese Version of the Chronic Pain Coping Inventory (ChCPCI) in a Hong Kong Chinese Population

The Chronic Pain Coping Inventory (CPCI) is a frequently used measure that assesses 8 categories of coping strategies that patients might use to cope with chronic pain. Despite its good psychometric properties and widespread use, the instrument has not been tested for its applicability and validity in non-Western populations, such as among Chinese. This study evaluated the reliability and validity of a Chinese translation of the 42-item CPCI (ChCPCI-42) in a sample of Chinese patients with chronic pain (n = 208). In addition to the ChCPCI-42, the patients were administered the Chronic Pain Grade (CPG) questionnaire, the Pain Catastrophizing Scale (PCS), the Centre for Epidemiological Studies-Depression Scale (CES-D), and questions assessing sociodemographic characteristics. Results of confirmatory factor analyses revealed that of the ChCPCI-42 8 scales, 6 demonstrated acceptable-to-good data-model fit (CFI ≥ 0.90) and 2 demonstrated medium fit (CFI ≥ 0.85). The 8 scales demonstrated adequate to good internal consistency (Cronbach α, 0.69 to 0.79) and correlated with CES-D, PCS, pain intensity, and disability in expected directions. Results of hierarchical multiple regression analyses showed that the ChCPCI-42 scales predicted concurrent depression (F (8,177) = 3.07, P < .01) and pain disability (F (1, 179) = 4.35, P < .001) scores, the Task Persistence scale being the strongest unique predictor among the 8 scales. The findings support the factorial validity and reliability of a 42-item CPCI that can be used among Chinese patients with chronic pain. Perspective: The report outlines the first validation of the CPCI for use in Hong Kong Chinese. This makes available a suitable instrument for chronic pain research in the Southern Chinese population and will help to elucidate similarities and differences in pain coping between Chinese and other ethnic groups. © 2010 American Pain Society.postprin

A computational model of the hypothalamic - pituitary - gonadal axis in female fathead minnows (Pimephales promelas) exposed to 17α-ethynylestradiol and 17β-trenbolone

© 2011 Li et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background - Endocrine disrupting chemicals (e.g., estrogens, androgens and their mimics) are known to affect reproduction in fish. 17α-ethynylestradiol is a synthetic estrogen used in birth control pills. 17β-trenbolone is a relatively stable metabolite of trenbolone acetate, a synthetic androgen used as a growth promoter in livestock. Both 17α-ethynylestradiol and 17β-trenbolone have been found in the aquatic environment and affect fish reproduction. In this study, we developed a physiologically-based computational model for female fathead minnows (FHM, Pimephales promelas), a small fish species used in ecotoxicology, to simulate how estrogens (i.e., 17α-ethynylestradiol) or androgens (i.e., 17β-trenbolone) affect reproductive endpoints such as plasma concentrations of steroid hormones (e.g., 17β-estradiol and testosterone) and vitellogenin (a precursor to egg yolk proteins). Results - Using Markov Chain Monte Carlo simulations, the model was calibrated with data from unexposed, 17α-ethynylestradiol-exposed, and 17β-trenbolone-exposed FHMs. Four Markov chains were simulated, and the chains for each calibrated model parameter (26 in total) converged within 20,000 iterations. With the converged parameter values, we evaluated the model's predictive ability by simulating a variety of independent experimental data. The model predictions agreed with the experimental data well. Conclusions - The physiologically-based computational model represents the hypothalamic-pituitary-gonadal axis in adult female FHM robustly. The model is useful to estimate how estrogens (e.g., 17α-ethynylestradiol) or androgens (e.g., 17β-trenbolone) affect plasma concentrations of 17β-estradiol, testosterone and vitellogenin, which are important determinants of fecundity in fish.The Medical Research Foundation of Oregon, U.S. Environmental Protection Agency, and the National Center for Computational Toxicology of the EPA Office of Research and Development

Groundwater recharge influenced by ephemeral river flow and land use in the semiarid Limpopo Province of South Africa

Determining the sustainability of groundwater use in drylands with high climate variability is complex. Central to this determination is an understanding of groundwater recharge and associated processes and controls. Groundwater recharge in drylands can occur by diffuse and focused recharge (focused recharge being associated with intense episodic rainfall events and ephemeral river flow, predicted to increase and intensify with climate change). This study evaluated the relative significance and dominant controls on these two recharge processes. Ten groundwater hydrographs with multidecadal observations were collated from the Limpopo Province, South Africa, based on their proximity to river channels and rain gauges, representing diversity in local climate, landscape, vegetation, and hydrogeological conditions. The hydrographs showed that groundwater-level rises are sensitive to rainfall intensity during the rainy season, with generally larger increases after years with large episodic rainfall events, which disproportionately contribute to groundwater replenishment. Recharge processes and annual recharge volumes were quantified using the water-table fluctuation method and the numerical model HYDRUS-1D. This allowed for the inference of additional recharge contributions from focused recharge in proximity to ephemeral rivers, up to a factor of five relative to diffuse recharge. The analysis revealed synchronicity and linear correlation between annual river discharge and recharge close to the river, substantiating the importance of focused recharge close to the river network. The study showed that recharge in drylands is subject to large spatial and temporal variation and that consideration of focused and episodic recharge is critically important for managing groundwater resources at various scales in these regions

Universal description of the rotational-vibrational spectrum of three particles with zero-range interactions

A comprehensive universal description of the rotational-vibrational spectrum for two identical particles of mass $m$ and the third particle of the mass $m_1$ in the zero-range limit of the interaction between different particles is given for arbitrary values of the mass ratio $m/m_1$ and the total angular momentum $L$. If the two-body scattering length is positive, a number of vibrational states is finite for $L_c(m/m_1) \le L \le L_b(m/m_1)$, zero for $L>L_b(m/m_1)$, and infinite for $L<L_c(m/m_1)$. If the two-body scattering length is negative, a number of states is either zero for $L \ge L_c(m/m_1)$ or infinite for $L<L_c(m/m_1)$. For a finite number of vibrational states, all the binding energies are described by the universal function $\epsilon_{LN}(m/m_1) = {\cal E}(\xi, \eta)$, where $\xi=\displaystyle\frac{N-1/2}{\sqrt{L(L + 1)}}$, $\eta=\displaystyle\sqrt{\frac{m}{m_1 L (L + 1)}}$,and $N$ is the vibrational quantum number. This scaling dependence is in agreement with the numerical calculations for $L > 2$ and only slightly deviates from those for $L = 1, 2$. The universal description implies that the critical values $L_c(m/m_1)$ and $L_b(m/m_1)$ increase as $0.401 \sqrt{m/m_1}$ and $0.563 \sqrt{m/m_1}$, respectively, while a number of vibrational states for $L \ge L_c(m/m_1)$ is within the range $N \le N_{max} \approx 1.1 \sqrt{L(L+1)}+1/2$

Poroelastic Modelling of CSF circulation via the incorporation of experimentally derived microscale water transport properties

We outline how multicompartmental poroelasticity is applied to the study of dementia. We utilize a 3D version of our poroelastic code to investigate the effects within parenchymal tissue. This system is coupled with multiple pipelines within the VPH-DARE@IT project which account for patient/subject-specific boundary conditions in the arterial compartment, in addition to both an image segmentation-mesh and integrated cardiovascular system model pipeline respectively. This consolidated template allows for the extraction of boundary conditions to run CFD simulations for the ventricles. Finally, we outline some experimental results that will help inform the MPET system

The influence of groundwater abstraction on interpreting climate controls and extreme recharge events from well hydrographs in semi-arid South Africa

There is a scarcity of long-term groundwater hydrographs from sub-Saharan Africa to investigate groundwater sustainability, processes and controls. This paper presents an analysis of 21 hydrographs from semi-arid South Africa. Hydrographs from 1980 to 2000 were converted to standardised groundwater level indices and rationalised into four types (C1–C4) using hierarchical cluster analysis. Mean hydrographs for each type were cross-correlated with standardised precipitation and streamflow indices. Relationships with the El Niño–Southern Oscillation (ENSO) were also investigated. The four hydrograph types show a transition of autocorrelation over increasing timescales and increasingly subdued responses to rainfall. Type C1 strongly relates to rainfall, responding in most years, whereas C4 notably responds to only a single extreme event in 2000 and has limited relationship with rainfall. Types C2, C3 and C4 have stronger statistical relationships with standardised streamflow than standardised rainfall. C3 and C4 changes are significantly (p < 0.05) correlated to the mean wet season ENSO anomaly, indicating a tendency for substantial or minimal recharge to occur during extreme negative and positive ENSO years, respectively. The range of different hydrograph types, sometimes within only a few kilometres of each other, appears to be a result of abstraction interference and cannot be confidently attributed to variations in climate or hydrogeological setting. It is possible that high groundwater abstraction near C3/C4 sites masks frequent small-scale recharge events observed at C1/C2 sites, resulting in extreme events associated with negative ENSO years being more visible in the time series