Feed supplementation with biochar may reduce poultry pathogens, including Campylobacter hepaticus, the causative agent of Spotty Liver Disease

Increased global regulation and restrictions on the non-therapeutic use of antibiotics in the poultry industry means that there is a need to identify alternatives that prevent infection while still conveying the growth and performance benefits afforded by their use. Biochars are produced by the incomplete pyrolysis of organic materials, with reports of use as a feed supplement and activity against pathogenic bacteria. In the current study the dose-dependent effects of biochar dietary inclusion in layer diets at 1%, 2% and 4% w/w were investigated to determine a) the efficacy of biochar as an anti-pathogenic additive on the intestinal microbiota and b) the optimal inclusion level. Biochar inclusion for anti-pathogenic effects was found to be most beneficial at 2% w/w. Poultry pathogens such as Gallibacterium anatis and campylobacters, including Campylobacter hepaticus, were found to be significantly lower in biochar fed birds. A shift in microbiota was also associated with the incorporation of 2% w/w biochar in the feed in two large scale trials on two commercial layer farms. Biochar inclusion for anti-pathogenic effects was found to be most beneficial at 2% w/w. Differential effects of the timing of biochar administration (supplementation beginning at hatch or at point of lay) were also evident, with greater impact on community microbial structure at 48 weeks of age when birds were fed from hatch rather than supplemented at point of lay.Nicky-Lee Willson, Thi T.H. Van, Surya P. Bhattarai, Jodi M. Courtice, Joshua R. McIntyre, Tanka P. Prasai, Robert J. Moore, Kerry Walsh, Dragana Stanle

The Cholecystectomy As A Day Case (CAAD) Score: A Validated Score of Preoperative Predictors of Successful Day-Case Cholecystectomy Using the CholeS Data Set

Background Day-case surgery is associated with significant patient and cost benefits. However, only 43% of cholecystectomy patients are discharged home the same day. One hypothesis is day-case cholecystectomy rates, defined as patients discharged the same day as their operation, may be improved by better assessment of patients using standard preoperative variables. Methods Data were extracted from a prospectively collected data set of cholecystectomy patients from 166 UK and Irish hospitals (CholeS). Cholecystectomies performed as elective procedures were divided into main (75%) and validation (25%) data sets. Preoperative predictors were identified, and a risk score of failed day case was devised using multivariate logistic regression. Receiver operating curve analysis was used to validate the score in the validation data set. Results Of the 7426 elective cholecystectomies performed, 49% of these were discharged home the same day. Same-day discharge following cholecystectomy was less likely with older patients (OR 0.18, 95% CI 0.15–0.23), higher ASA scores (OR 0.19, 95% CI 0.15–0.23), complicated cholelithiasis (OR 0.38, 95% CI 0.31 to 0.48), male gender (OR 0.66, 95% CI 0.58–0.74), previous acute gallstone-related admissions (OR 0.54, 95% CI 0.48–0.60) and preoperative endoscopic intervention (OR 0.40, 95% CI 0.34–0.47). The CAAD score was developed using these variables. When applied to the validation subgroup, a CAAD score of ≤5 was associated with 80.8% successful day-case cholecystectomy compared with 19.2% associated with a CAAD score >5 (p < 0.001). Conclusions The CAAD score which utilises data readily available from clinic letters and electronic sources can predict same-day discharges following cholecystectomy

Whole-genome sequencing reveals host factors underlying critical COVID-19

Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease

Determination Of Thermodynamic And Kinetic Parameters From Isothermal Heat Conduction Microcalorimetry: Applications To Long-term-reaction Studies

The application of heat conduction isothermal microcalorimetry has been proposed for some time as a rapid and general technique for the determination of both thermodynamic and kinetic parameters of chemical reactions. These applications have been suggested as being of particular relevance to solid-state reactions and, industrially important, to the prediction of long-term stability and of compatibility data for pharmaceutical materials. However, there has yet to be the development of a general procedure that does not require additional noncalorimetric data and that is free of assumptions, which can be used to determine the thermodynamic and kinetic parameters for a reaction, from calorimetric data. It is the purpose of this paper to describe such a general approach which does not depend upon knowledge of initial concentrations (quantity), enthalpy, or any predetermined reaction order. Equations have been developed which incorporate calorimetrically accessible data (Φ, the power, and q, the heat output) and which also include the rate constant, k, the change in enthalpy of the reaction, ΔH, and the order of reaction. A second procedure is also described which depends only on the analysis of the calorimetric signal and which involves no formal chemical kinetic based equations. The methods described allow estimation of, for example, the annual extent of degradation of a solid compound. The methods developed have been tested through examination of both calculated and experimental data. The experimental work examined very slow reactions (lifetime of years) of known order (there are little reliable enthalpy data available for slow reactions) and involved calorimetric observation of these reactions for up to 50 h. In all cases, the method yielded the appropriate, i.e., conforms to literature data, rate constant, reaction order, and, where available, reaction enthalpy. Some situations in which this microcalorimetric approach and subsequent data analysis will be of utility are discussed. © 1995 American Chemical Society.99187108711

A possible mechanism for the action of the novel anthelmintic emodepside, using Ascaris suum body wall muscle preparations

The increasing resistance of parasitic nematodes, to existing anthelmintics has encouraged the search for novel compounds. A potential anthelmintic PF1022A, a 24 membered cyclic depsipeptide, has been shown to act as a potent broad-spectrum anthelmintic (Von Samson-Himmelstjerna et al. 2000). PF1022A causes a fast onset of paralysis of the nematodes, favouring the view that it is neuropharmalogically active. This study investigates the in vitro effects of a semi-synthetic, structurally similar derivative, emodepside, on the pig intestinal parasite Ascaris suum. Ascaris dorsal muscle strips (DMS) were bathed in artificial perienteric fluid (APF) (Trim et al. 1997). Statistical comparison was by Student's paired or unpaired t test, as stated. As a control, the DMS was contracted using acetylcholine (30 µM, 10 min) and maximum contraction was normalised to 100 %. A slow relaxation of the DMS was then observed over a period of 10 min. Addition of 10 µM emodepside at the point of maximum contraction, caused a significantly (P &lt; 0.005, unpaired) faster relaxation of the DMS, 9.0 ± 0.3 % min-1 (mean ± S.E.M., n = 5), compared with the ACh control (6.1 ± 0.6 % min-1, n = 5).The effects of emodepside on Ascaris somatic muscle cells were investigated using a 2-microelectrode set-up. A 2 min perfusion of emodepside over muscle cells caused a significant (P &lt; 0.001, paired) slow hyperpolarisation of 5.5 ± 0.96 mV (n = 8), with no change in input conductance after 30 min. In the absence of calcium, 10 µM emodepside caused no significant change in membrane potential. Re-introduction of calcium resulted in a slow significant (P &lt; 0.002, paired) hyperpolarisation of 5.5 ± 1.1 mV (n = 8).Perfusion of the muscle cells with the potassium channel blockers 4-aminopyridine (4AP, 250 µM) and tetra-ethylammonium (TEA, 5 mM) resulted in a slight depolarisation of muscle cells 2.8 ± 0.5 mV (n = 5). Emodepside (10 µM) was then applied, and no significant change in the membrane potential occurred. Following wash-out of 4AP and TEA, the membrane potential hyperpolarized by 5.2 ± 2 mV (n = 5) over a 30 min period, although this effect was not significant. These results indicate that potassium is required for emodepside hyperpolarisation and this, combined with the results with calcium-free APF, suggests that this compound's relaxation effect may be mediated via a calcium-activated potassium channel. <br/

Characterization of 5-HT receptors in the parasitic nematode, Ascaris suum

The pharmacological profiles of the 5-hydroxytryptamine (5-HT) receptors on Ascaris suum pharyngeal and somatic body wall muscles were investigated. The mechanisms involved following activation of these receptors were also studied. 5-HT activated and maintained pumping in isolated pharynxes with an EC-50 value of 44±1·7?M. The 5-HT agonists, tryptamine, sumatriptan 8-OH-DPAT and 5-carboxyamidotryptamine all failed to stimulate pumping. The 5-HT2 antagonist, ketanserin, initially excited and then inhibited pumping while the 5-HT3 antagonist, ondansetron, had no effect. 5-HT and 5-HT agonists, 8-OH-DPAT, 5-carboxyamidotryptamine, ?-methyl-5-HT and tryptamine all inhibited ACh-induced contractions of a somatic body wall muscle strip. Ketanserin partially blocked the inhibitory effect of ?-methyl-5-HT and ACh-induced contractions while the 5-HT uptake blocker, fluoxetine, potentiated the effect of 5-HT on ACh-induced contractions. Basal levels of cAMP, 1540±232pmol/mg, in pharyngeal muscle and 1721±134pmol/mg, somatic body wall muscle, were both increased by forskolin. 5-HT had no effect on pharyngeal muscle cAMP levels but raised cAMP levels in somatic body wall muscle, e.g. 100?M 5-HT, raised the level to 2851±212pmol/mg and 1000?M raised levels to 4578±1234pmol/mg., 1000?M, increased inositol phosphate levels in pharyngeal muscle. These results provide some evidence for a 5-HT2-like receptor on pharyngeal muscle. In contrast, the situation on somatic body wall muscle is more confusing since the pharmacological profile partly indicates a 5-HT2-like receptor but this receptor is linked to a rise in cAMP levels. Further studies are required to resolve the position but they must be based on the rational design of ligands specifically for nematode 5-HT receptors and not simply using ligands developed for the classification of mammalian 5-HT receptors. Such a design must take into account data from molecular biology studies of nematode 5-HT receptors

The effect of the anthelmintic emodepside at the neuromuscular junction of the parasitic nematode Ascaris suum

Here we report on the action of the novel cyclo-depsipeptide anthelmintic, emodepside, on the body wall muscle of the parasitic nematode, Ascaris suum. Emodepside caused (i) muscle relaxation, (ii) inhibition of muscle contraction elicited by either acetylcholine (ACh), or the neuropeptide, AF2 (KHEYLRFamide) and (iii) a rapid relaxation of muscle tonically contracted by ACh. The inhibitory action of emodepside on the response to ACh was not observed in a denervated muscle strip, indicating that it may exert this action through the nerve cord, and not directly on the muscle. Electrophysiological recordings showed emodepside elicited a Ca++-dependent hyperpolarization of muscle cells. Furthermore, the response to emodepside was dependent on extracellular K+, similar to the action of the inhibitory neuropeptides PF1 and PF2 (SDPNFLRFamide and SADPNFLRFamide). Thus emodepside may act at the neuromuscular junction to stimulate release of an inhibitory neurotransmitter or neuromodulator, with a similar action to the PF1/PF2 neuropeptides