Impact and process evaluation of a primary-school Food Education and Sustainability Training (FEAST) program in 10-12-year-old children in Australia: pragmatic cluster non-randomized controlled trial

BACKGROUND

Environmentally sustainable food initiatives accompanying nutrition education, such as the Food Education and Sustainability Training (FEAST) program, have gained traction in school settings. The aim of this trial was to conduct an impact and process evaluation of FEAST, to evaluate its effect on children's fruit and vegetable (F&V) intakes, and secondary outcomes: F&V variety consumed, nutrition knowledge, food preparation/cooking skills, self-efficacy and behaviours, food waste knowledge and behaviours, and food production knowledge.

METHODS

FEAST was a 10-week curriculum-aligned program, designed to educate children about healthy eating, food waste, and sustainability, while teaching cooking skills. It was implemented by classroom teachers, face-to-face and online, during COVID-19 school closures, in Australia in 2021. A custom designed survey was used to collect baseline and post-intervention data from students. Generalised linear mixed models (GLMM) estimated group differences in pre-post changes for primary and secondary outcomes. Surveys were also administered to students and teachers to evaluate intervention implementation.

RESULTS

Twenty schools participated and self-selected to be either intervention schools (n = 10) or wait-list control (WLC) schools (n = 10). A total of 977, 5th and 6th grade children participated in the trial with a mean age of 11.1 years (SD ± 0.7). The FEAST intervention, compared to WLC, did not result in significant increases in primary outcomes nor secondary outcomes. The process evaluation revealed FEAST was well-received by students and teachers, but COVID-19 school closures hindered implementation fidelity with a less intense program delivered under the constraints of pandemic lockdowns.

CONCLUSIONS

This is the first cluster non-randomized controlled trial designed to independently evaluate FEAST in the primary-school setting. No evidence was found for improved F&V intakes in children, nor secondary outcomes. However, the positive process evaluation results suggest that further trials of the program are warranted. If implemented as originally designed (pre-pandemic), with increased duration and complemented by supporting school policies, such programs have the potential to improve children's daily F&V intakes, cooking skills and food waste behaviours. This would support the Australian curriculum and contribute to: health promotion within schools and sustainable schools initiatives, the national agenda to reduce food waste and sustainable development goals. AUSTRALIAN AND NEW ZEALAND CLINICAL TRIALS REGISTRY: [ACTRN12620001347954]- Registered prospectively on 14/12/2020.

Oxylipin profiling by LC-ESI-MS/MS in canine serum and plasma to investigate ovulation-specific changes

New biomarkers that are directly associated with canine ovulation would be of value to ensure mating on optimal days of heat. In this study, canine plasma and serum were analyzed with liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) to quantify a broad range of oxylipins for the purpose of developing a method for biomarker discovery studies in canine reproduction. A majority of the 67 oxylipins probed for were detected at comparable levels in both sample types, but more oxylipins at higher concentrations were detected in serum than in plasma. Nine of the oxylipins were detected in a pilot study of serum at levels that significantly differed (p ≤ 0.1) between time-points before (n = 10), during (n = 10) and after (n = 10) ovulation, and might serve as putative biomarkers for canine ovulation. One oxylipin (20-HETE) was significantly altered after adjusting for multiple comparisons. In conclusion, the results showed that the LC-ESI-MS/MS method was suitable for quantification of canine oxylipins, revealing important similarities and differences between plasma and serum profiles as well as preliminary ovulation-specific changes in a subset of the investigated oxylipins.

Effects of conventionally treated and ozonated wastewater on the damselfly larva oxylipidome in response to on-site exposure

Pharmaceutical residues discharged through insufficiently treated or untreated wastewater enter aquatic environments, where they may adversely impact organisms such as aquatic invertebrates. Ozonation, an advanced wastewater treatment technique, has been successfully implemented to enhance the removal of a broad range of pharmaceuticals, however diverse byproducts and transformation products that are formed during the ozonation process make it difficult to predict how ozonated wastewater may affect aquatic biota. The aim of this study was to investigate effects on fatty acid metabolites, oxylipins, in a common invertebrate species, damselfly larvae, after on-site exposure to conventional wastewater treatment plant (WWTP) effluent and additionally ozonated effluent at a full-scale WWTP. Subsequent ozonation of the conventionally treated wastewater was assessed in terms of i) removal of pharmaceuticals and ii) potential sub-lethal effects on the oxylipidome. Northern damselfly (Coenagrion hastulatum) larvae were exposed for six days in the treatment plant facility to either conventional WWTP effluent or ozonated effluent and the effects on pharmaceutical levels and oxylipin levels were compared with those from tap water control exposure. Ozonation removed pharmaceuticals at an average removal efficiency of 67% (ozone dose of 0.49 g O₃/g DOC). Of 38 pharmaceuticals detected in the effluent, 16 were removed to levels below the limit of quantification by ozonation. Levels of two oxylipins, 12(13)-EpODE and 15(16)-EpODE, were reduced in larvae exposed to the conventionally treated wastewater in comparison to the tap water control. 15(16)-EpODE was reduced in the larvae exposed to ozonated effluent in comparison to the tap water control. One oxylipin, 8-HETE, was significantly lower in larvae exposed to conventional WWTP effluent compared to ozonated effluent. In conclusion, the study provides proof-of-principle that damselfly larvae can be used on-site to test the impact of differentially treated wastewater.

The path to evidence-based guidelines for food insecurity during pregnancy

Background

Food insecurity has negative health implications during and after pregnancy, however, identifying and then assisting women who are food insecure is complex. Successful screening programs are often embedded in practice guidelines that include referral and treatment guidance. Screening for food insecurity is vital to address food insecurity, however, it is not present in Australia, nor are there any guidelines for healthcare settings. This presentation will describe the steps taken to gather evidence to inform the development of practice guidelines.

Methods

The creation of practice guidelines for screening and responding to the needs of food insecure pregnant women was informed by 1) qualitative interviews with food insecure pregnant women, and 2) qualitative interviews with clinicians about their experiences of assisting hungry and food insecure pregnant women, 3) quantitative research with a cross-section of pregnant women about their experiences managing their food supply, 4) a systematic review describing the existing interventions addressing food insecurity during pregnancy, and 5) a modified Delphi to gather the opinions of experts on the best ways to address food insecurity in pregnancy.

Results

This work highlight the potential effectiveness of a food insecurity screening tool in the antenatal setting, the readiness of clinicians to respond to this need, the breadth and depth of current interventions to address food insecurity, and the opinions of experts on how this issue needs to be addressed. The combined impact of these 5 studies is the identification of a number of responces to food insecurity and hunger during pregnancy.

Conclusions

Given the lack of screening, standard care, and treatment of food insecurity in a clinical setting in Australia, it is essentail that guidelines are created that standardise patient care and control costs through efficient use of health care resources.

Key messages

• Food insecurity during pregnancy has significant implications for both mother and baby.

• Creating supportive evidence-based mechanisms to address food insecurity will lead to positive outcomes.

Evaluating OzHarvest's primary-school Food Education and Sustainability Training (FEAST) program in 10-12-year-old children in Australia: protocol for a pragmatic cluster non-randomized controlled trial

Background

The promotion of healthy eating is a public health priority. Poor dietary behaviours, including low fruit and vegetable (F&V) consumption are of particular concern among children. Novel nutrition promotion strategies are needed to improve F&V consumption. Sustainability education could be used to support nutrition education within the school context. The purpose of this paper is to report the protocol for impact and process evaluation of the school-based Food Education and Sustainability Training (FEAST) program, designed to educate children about sustainability, food waste and nutrition, using hands-on cooking activities.

Methods

A pragmatic, parallel, cluster non-randomized controlled trial with pre- and post-measures, will be implemented among 20 primary schools (10 intervention vs 10 wait-list-control) within NSW, Australia, involving children in Grades 5–6. FEAST is a curriculum-aligned program, delivered as a 1.5-h lesson/week, for a 10-week unit of inquiry, incorporating theory and cooking. FEAST was developed using theoretical frameworks which included Social Cognitive Theory and the Precede-Proceed Planning model. Primary outcomes include children’s self-reported F&V intakes (serves/day). Food literacy constructs such as: nutrition knowledge, food preparation and cooking skills, self-efficacy and behaviours, food waste knowledge and behaviours and food production knowledge, will be assessed as secondary outcomes. Process evaluation will assess program reach, adoption, implementation, maintenance, satisfaction and perceived benefits by teachers and students. An online survey (including quantitative and qualitative questions) was developed for administration at baseline (impact evaluation) and immediately post-intervention (impact and process evaluation). Intervention effects on quantitative study outcomes will be estimated with ​generalised linear mixed models, including random effects and will follow the intention-to-treat principles. Open-ended questions embedded within the surveys will be analysed qualitatively using content and thematic analyses.

Discussion

Results from this trial will provide valuable information on the value of adding environmental sustainability strategies to nutrition education in schools. Results will inform the design of future research and programs focused on primary-school children’s nutrition, sustainability-related behaviours and experiential school-based interventions.

Trial registration

Trial registered 14th December 2020 with the Australian and New Zealand Clinical Trials Registry (ACTRN12620001347954).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10302-0.

Plasma oxylipin levels associated with preterm birth in preterm labor✰

INTRODUCTION

Preterm labor is a common clinical problem in obstetrics. Since the majority of women with preterm labor eventually deliver at full term, biomarkers are needed to more accurately predict who will deliver preterm. Oxylipins, given their importance in inflammation regulation, are highly interesting in this respect since labor is an inflammatory process.

METHODS

Eighty women with preterm labor before 34 weeks of gestation were enrolled in a prospective observational multi-center cohort study. Oxylipin levels of 67 analytes in plasma samples were analyzed by liquid chromatography coupled to tandem mass spectrometry.

RESULTS

Twenty-one (26%) of the women delivered before 34 weeks of gestation, and of those women, fourteen delivered within 48 h of admission. Logistic multivariate regression showed that lower levels of 9,10-DiHODE were associated with delivery before 34 weeks of gestation (aOR 0.12 (0.024-0.62)) and within 48 h ((aOR 0.13 (0.019-0.93)). Furthermore, higher levels of 11,12-DiHETrE were associated with delivery before 34 weeks of gestation ((aOR 6.19 (1.17-32.7)) and higher levels of 8-HETE were associated with delivery within 48 h ((aOR 5.01 (1.13-22.14)).

CONCLUSIONS

The oxylipin 9,10-DiHODE may be protective in preterm labor, both for delivery after 34 weeks of gestation and for delivery later than 48 h of admission, whereas 11,12-DiHETrE and 8-HETE display the opposite effect. Larger studies are needed to validate these mediators as biomarkers for prediction of preterm birth following preterm labor.

Oxylipins at intermediate larval stages of damselfly Coenagrion hastulatum as biochemical biomarkers for anthropogenic pollution

Aquatic pollution resulting from anthropogenic activities requires adequate environmental monitoring strategies in sentinel organisms. Thus, biochemical biomarkers have been used as early-warning tools of biological effects in aquatic organisms. However, before using these markers for environmental monitoring, knowledge about their developmental variation is vital. In this study, we assessed baseline levels and developmental variations of a group of potential biomarkers, oxylipins, during the lifespan of the Northern damselfly (Coenagrion hastulatum) using liquid chromatography-tandem mass spectrometry. Effects of wastewater exposure on baseline levels were studied in a subset of damselflies to investigate the responsiveness due to anthropogenic pollution. Thirty-eight oxylipins deriving from four polyunsaturated fatty acids via two enzymatic pathways were detected in damselflies at three larval stages and in the adult form. Overall, oxylipin baseline levels showed developmental variation, which was lowest in the intermediate larval stages. Effects of exposure to wastewater effluent on oxylipin baseline levels were dependent on the life stage and were greatest in the early and intermediate larval stages. The study provides first insights into oxylipin profiles of damselflies at different stages of development and their developmental variation. Based on our results, we propose further strategies for incorporating oxylipins in damselfly larvae as biochemical markers for anthropogenic pollution.

Polyunsaturated Fatty Acids and Their Metabolites in Hyperemesis Gravidarum

Polyunsaturated fatty acids (PUFAs) have been studied in relation to pregnancy. However, there is limited knowledge on PUFAs and their metabolites in relation to hyperemesis gravidarum (HG), a pregnancy complication associated with nutritional deficiencies and excessive vomiting. In order to survey the field, a systematic review of the literature was performed, which also included nausea and vomiting of pregnancy (NVP) due to its close relationship with HG. In the very few published studies found, the main subjects of the research concerned free fatty acids (four records), lipid profiles (three records), and bioactive lipids (one article about prostaglandin E₂ and one about endocannabinoids). The authors of these studies concluded that, although no cause-and-effect relationship can be established, HG is linked to increased sympathetic responsiveness, thermogenic activity and metabolic rate. In addition, NVP is linked to a metabolic perturbance (which lasts throughout pregnancy). The low number of retrieved records underlines the need for more research in the area of PUFAs and HG, especially with regard to the underlying mechanism for the detected effects, potentially involving growth differentiation factor 15 (GDF15) since evidence for GDF15 regulation of lipid metabolism and the role for GDF15 and its receptor in nausea and vomiting is emerging.

Quantification of total concentration of thiol functional groups in environmental samples by titration with monobromo(trimethylammonio)bimane and determination with tandem mass spectrometry

Thiol compounds (R-SH) have many important biological functions and are principal controls of the speciation of several toxic metals in the environment. However, determining the concentration of thiols associated with environmental matrices is challenging due to the compounds' low abundance and interferences from non-thiol compounds for many available methods. Here a novel method has been developed and validated to quantify the total concentration of thiol functional groups in aqueous samples using derivatization with monobromo(trimethylammonio)bimane (qBBr) and quantification with tandem mass spectrometry. The thiol concentration was determined by titration of the sample with qBBr, which reacts selectively with thiols, and quantification of the residual qBBr. We systematically evaluated potential interferences from various organic compounds, inorganic ions (including sea water matrices), sulfide and mercury (Hg) species, and demonstrate that the method is highly sensitive, selective and robust. The limit of detection (LOD) for total thiols is in the nanomolar concentration range (~6 nM). The method performance was also demonstrated by determination of the total thiol concentration in different natural samples including boreal stream water (1.16 μM), wetland porewater (0.96 μM) and the Suwanee River natural organic matter (NOM) reference material SR101 N (7.9 μmol g^-1). The developed method represents a combination of low LOD and high selectivity and robustness that is unsurpassed for total thiol concentration measurements.

Novel metabolomic method to assess the effect-based removal efficiency of advanced wastewater treatment techniques

Unprecedented levels of chemicals of anthropogenic origin are currently released into surface waters globally. Wastewater treatment plant effluent has been identified as a major source, containing a broad mixture of pharmaceuticals and consumer chemicals. Therefore, there is a need for implementation of advanced wastewater treatment techniques, such as ozonation and adsorption methods, to reduce the contamination. However, there are conflicting findings on the toxicity of treated effluent and only limited possibilities for assessing the effect-based removal efficiency (EBRE) of different treatment techniques. Here, we describe a metabolomics approach to detect perturbations in fatty acid catabolic pathways as a proxy for biological effects. Metabolites in three fatty acid pathways were analyzed in a common damselfly larva (Coenagrion hastulatum) by liquid chromatography coupled to mass spectrometry. The larvae were exposed for one week to either conventionally treated effluent (activated sludge treatment), effluent additionally treated with ozone or effluent additionally treated with biochar filtration and results were compared with those from tap water control exposure. Five lipoxygenase-derived oxylipins (9,10,13-TriHOME, 9,12,13-TriHOME, 9-HODE, 9-HOTrE, and 13-HOTrE) decreased in response to conventionally treated effluent exposure. By using an additional treatment step, oxylipin levels were restored with exception of 9,10,13-TriHOME (ozonated effluent), and 9-HOTrE and 13-HOTrE (effluent filtered with biochar). In conclusion, exposure to wastewater effluent affected fatty acid metabolite levels in damselfly larvae, and a subset of the analyzed metabolites may serve as indicators for biological effects in biota in response to effluent exposure. To that effect, our findings suggest a new metabolomics protocol for assessing EBRE.

Myenteric networks of interstitial cells of Cajal are reduced in horses with inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is a well-recognised but poorly understood disease complex in the horse. Clinical signs may vary but often include weight loss, diarrhoea and colic. The effect this disease process may have on the gastrointestinal pacemaker cells (the interstitial cells of Cajal), enteric neurons and glial cells has not been previously evaluated in the horse.

OBJECTIVES

To compare the density of the interstitial cells of Cajal (ICC), enteric neurons and glial cells in horses with IBD to those of normal horses using immunohistochemical markers.

STUDY DESIGN

Retrospective, quantitative immunohistochemical study.

METHODS

Ileal samples were collected during post-mortem examinations from 14 horses with a clinical and histopathological diagnosis of IBD and from eight normal controls. All horses were Standardbreds 1-15 years of age. Six of the IBD cases had eosinophilic gastroenteritis (EG) while the remaining eight had granulomatous enteritis (GE). Tissue sections were labelled with anti-CD117 (c-Kit), anti-TMEM16 (TMEM16), anti-protein gene product (PGP9.5) and anti-glial fibrillary acidic protein (GFAP) using standard immunohistochemical labelling techniques. Image analysis was performed to quantify the presence of ICC (CD117, TMEM16) as well as neuronal (PGP9.5) and enteroglial (GFAP) networks.

RESULTS

Interstitial cells of Cajal networks were significantly reduced in the myenteric plexus (MP) region in IBD horses compared with the controls for both markers (P<0.05). There was no significant difference in the density of the neuronal or glial cell markers between the two groups (P>0.05).

MAIN LIMITATIONS

The number of horses included in the study.

CONCLUSIONS

Disruption to ICC networks may contribute to the clinical signs of colic in some horses with IBD. Further studies are needed to establish the pathophysiological mechanisms involved and the functional effects of the reduced ICC networks.

New aspects of longitudinal instabilities in electron storage rings

Novel features of the longitudinal instability of a single electron bunch circulating in a low-emittance electron storage ring are discussed. Measurements and numerical simulations, performed both in time and frequency domain, show a non-monotonic increase of the electron beam energy spread as a function of single bunch current, characterized by the presence of local minima and maxima, where a local minimum of the energy spread is interpreted as a higher-order microwave instability threshold. It is also shown that thresholds related to the same zero-intensity bunch length depend linearly on the accelerating radio frequency voltage. The observed intensity-dependent features of the energy spread, confirmed by measurements with two independent diagnostics methods, i.e. horizontal beam profile measurements by a synchrotron light monitor and photon energy spectrum measurements of undulator radiation, are given a theoretical interpretation by applying a novel eigenvalue analysis based on the linearized Vlasov equation.

Adult weight management across the community: population-level impact of the LOSE IT to WIN IT challenge

Objective

Excess body weight negatively impacts health, but there are few evaluations of low-intensity weight management challenge programs in defined populations. This study examined weight change in adults who participated in the LOSE IT to WIN IT (LIWI) health challenge in a US community. The community-level impact on body mass index was also explored.

Methods

Body weight was analysed over 1 year in the cohort of LIWI enrolees, stratified by participants who were healthy weight or overweight/obese at baseline. Secondarily, a multiple cross-sectional analysis compared the 2.5-year trends in body mass index between community adults who did vs. did not participate in LIWI.

Results

LOSE IT to WIN IT participants who were overweight/obese lost a mean (95% confidence interval) 1.6 (1.2, 2.0) kg (~2%) over 1 year (p < 0.001), whereas healthy weight participants lost 0.7 (0.3, 1.1) kg. Across the community, LIWI participants and non-participants both gained 0.4 kg m-2 over the 2.5-year study period (p = 0.884).

Conclusions

LOSE IT to WIN IT was modestly effective among enrolees, resulting in a small weight loss of 2% over 1 year among those who were overweight/obese. However, LIWI did not impact weight gain in the community. To slow such community-level weight gain trends, weight management challenges must reach larger fractions of the populations that they target.

Percutaneousc Gastrostomy

Fluoroscopic percutaneous gastrostomy for the purpose of nutrition was performed in 28 patients with the aid of a specially designed gastrostomy set. No major complications were reported. Exchange to Foley catheter was performed after 7 days and could be used without complications for the patients' remaining life span. In order to evaluate the formation of a gastrocutaneous tract, an experimental study with the same instruments as in clinical practice was performed in 13 rabbits. Within one week a gastrocutaneous tract was formed, which was possible to dilate for insertion of a balloon catheter of larger size. The described procedure is a simple and time-saving method for a percutaneous gastrostomy in debilitated patients with dysphagia.

Early detection of neutralizing antibodies to interferon-beta in multiple sclerosis patients: binding antibodies predict neutralizing antibody development

BACKGROUND

Neutralizing antibodies (NAb) affect efficacy of interferon-beta (IFN-b) treatment in multiple sclerosis (MS) patients. NAbs evolve in up to 44% of treated patients, usually between 6-18 months on therapy.

OBJECTIVES

To investigate whether early binding antibody (BAb) titers or different IFN-b biomarkers predict NAb evolution.

METHODS

We included patients with MS or clinically isolated syndrome (CIS) receiving de novo IFN-b treatment in this prospective European multicenter study. Blood samples were collected at baseline, before and after the first IFN-b administration, and again after 3, 12 and 24 months on that therapy; for determination of NAbs, BAbs, gene expression of MxA and protein concentrations of MMP-9, TIMP-1, sTRAIL, CXCL-10 and CCL-2.

RESULTS

We found that 22 of 164 (13.4%) patients developed NAbs during a median time of 23.8 months on IFN-b treatment. Of these patients, 78.9% were BAb-positive after 3 months. BAb titers ≥ 1:2400 predicted NAb evolution with a sensitivity of 74.7% and a specificity of 98.5%. Cross-sectionally, MxA levels were significantly diminished in the BAb/NAb-positive samples; similarly, CXCL-10 and sTRAIL concentrations in BAb/NAb-positive and BAb-positive/NAb-negative samples, respectively, were also diminished compared to BAb/NAb-negative samples.

CONCLUSIONS

BAb titers reliably predict NAbs. CXCL-10 is a promising sensitive biomarker for IFN-b response and its abrogation by anti-IFN-b antibodies.

Expression of tlr4, md2 and cd14 in equine blood leukocytes during endotoxin infusion and in intestinal tissues from healthy horses

The expression of tlr4, md2 and cd14 was studied in equine blood leukocytes and in intestinal samples using real time PCR. The stability of three commonly used reference genes, glyceraldehyde-3P-dehydrogenase (GAPDH), hypoxantine ribosyltransferase (HPRT) and succinate dehydrogenase complex subunit A (SDHA), was evaluated using qbase(PLUS). The equine peripheral blood mononuclear cells (eqPBMC) examined were either stimulated in vitro with Phorbol 12-myristate 13-acetate (PMA) and ionomycin or with the CpG oligodeoxynuclotide 2216 (CpG-ODN 2216) or obtained from horses before, during and after infusion of endotoxin. Intestinal tissue from healthy horses was sampled at ileum, right dorsal colon and rectum. Ranking of the three reference genes used for normalisation identified the combination HPRT/SDHA as most suitable both when determined ex vivo in leukocytes obtained from experimentally induced endotoxaemia and in eqPBMC activated in vitro while HPRT/GAPDH were most appropriate for the intestinal samples. The relative amounts of mRNA for TLR4 and MD-2 increased threefold during in vitro activation of the cells with CpG-ODN 2216 but was decreased in cultures stimulated with PMA/ionomycin. A transient elevation in the transcription of tlr4 and md2 was also evident for equine blood leukocytes following endotoxaemia. The levels of mRNA for CD14 on the other hand remained unaffected both during the induction of endotoxaemia and in the in vitro stimulated PBMCs. A low steady expression of TLR4, MD-2 and CD14 mRNA was demonstrated for the intestinal samples with no variation between the intestinal segments analysed. Thus, the foundation for real time PCR based levels of analysis of mRNA for all three components in the equine LPS receptor complex in different intestinal segments was set, making it possible to carry out future expression studies on clinical material.

Understanding the physical interactions in the FGF21/FGFR/β-Klotho complex: structural requirements and implications in FGF21 signaling

The endocrine fibroblast growth factor 21 (FGF21) requires both fibroblast growth factor receptor (FGFR) and β-Klotho for signaling. In this study, we sought to understand the inter-molecular physical interactions in the FGF21/FGFR/β-Klotho complex by deleting key regions in FGFR1c or FGF21. Deletion of the D1 and the D1-D2 linker (the D1/linker region) from FGFR1c led to β-Klotho-independent receptor activation by FGF21, suggesting that there may be a direct interaction between FGF21 and the D1/linker region-deficient FGFR1c. Consistent with this, the extracellular portion of FGFR1c lacking the D1/linker region blocked FGF21 action in a reporter assay, presumably by binding to and sequestering FGF21 from acting on cell surface receptor complex. In addition, the D1/linker region-deficient FGFR1c had enhanced interaction with β-Klotho. Further, we demonstrated that deletion of the D1/linker region enhanced the formation of the FGF21/β-Klotho/FGFR1c ternary complex in both Biacore and asymmetrical flow field flow fractionation studies. Finally, we found that the N-terminus of FGF21 is involved in the interaction with FGFR1c and FGF21/β-Klotho/FGFR1c ternary complex formation. Taken together, our data suggest that the D1/linker region regulates both the FGF21/FGFR1c and FGFR1c/β-Klotho interaction, and a direct interaction of FGF21 with FGFR1c may be an important step in receptor-mediated FGF21 signaling.

The FGFR D3 domain determines receptor selectivity for fibroblast growth factor 21

FGF21 is a member of a unique subfamily of fibroblast growth factors that function as endocrine hormones and regulate a variety of metabolic activities. Unlike paracrine FGFs, FGF21 does not bind heparin and requires βKlotho as a co-receptor to activate FGFR signaling. In the presence of βKlotho, FGF21 is able to activate FGFRs 1c, 2c and 3c but not FGFR4. Chimeric FGFR1c/FGFR4 receptors were constructed to identify domains that confer this specificity and to understand regions important for FGF21-induced receptor activation. With these chimeras, we showed that domain 3 of the FGFR1c extracellular domain plays a critical role in specificity determination and receptor activation by FGF21. Furthermore, we were able to narrow down the sequences important for this function to a six amino acid region within domain 3 of FGFR1c. It is interesting to note that this region falls into the βC'-βE loop, which has been shown to be important for receptor specificity determination in paracrine FGFs, suggesting a common principle in both endocrine and paracrine FGF receptor interaction and activation.

Emittance-exchange-based high harmonic generation scheme for a short-wavelength free electron laser

Generation of short-wavelength radiation by a free-electron laser using up-frequency conversion of an electron bunch density modulation is currently an area of active research. We propose a new scheme for producing the longitudinal electron bunch density modulation similar to the recently proposed echo-enabled harmonic generation but based on an emittance exchange beam line and a multislit mask. Beam line analysis and start-to-end simulation are presented.

Mutational analysis of G-protein coupled receptor--FFA2

FFA2 (GPR43) is a receptor for short-chain fatty acids (SCFAs), acetate, and propionate. FFA2 is predominantly expressed in islets, a subset of immune cells, adipocytes, and the gastrointestinal tract which suggest a possible role in inflammatory and metabolic conditions. We have previously described the identification and characterization of novel phenylacetamides as allosteric agonists of FFA2. In the current study, we have investigated the molecular determinants contributing to receptor activation with the endogenous and synthetic ligands as well as allosteric interactions between these two sites. The mutational analysis revealed previously unidentified sites that may allosterically regulate orthosteric ligand's function as well as residues potentially important for the interactions between orthosteric and allosteric binding sites.

Allosteric rescuing of loss-of-function FFAR2 mutations

FFAR2 (GPR43) is a receptor for short-chain fatty acids (SCFAs), acetate and propionate. In the current study, we investigate the molecular determinants contributing to receptor activation by endogenous ligands. Mutational analysis revealed several important residues located in transmembrane domains (TM) 3, 4, 5, 6, and 7 for acetate binding. Interestingly, mutations that abolished acetate activity, including the mutation in the well-conserved D(E)RY motif, could be rescued by a recently identified synthetic allosteric agonist. These findings provide additional insight into agonist binding and activation which may aid in designing allosteric ligands for targeting receptor function in various diseases.

Separating mitogenic and metabolic activities of fibroblast growth factor 19 (FGF19)

FGF19 and FGF21 are distinctive members of the FGF family that function as endocrine hormones. Their potent effects on normalizing glucose, lipid, and energy homeostasis in disease models have made them an interesting focus of research for combating the growing epidemics of diabetes and obesity. Despite overlapping functions, FGF19 and FGF21 have many discrete effects, the most important being that FGF19 has both metabolic and proliferative effects, whereas FGF21 has only metabolic effects. Here we identify the structural determinants dictating differential receptor interactions that explain and distinguish these two physiological functions. We also have generated FGF19 variants that have lost the ability to induce hepatocyte proliferation but that still are effective in lowering plasma glucose levels and improving insulin sensitivity in mice. Our results add valuable insight into the structure-function relationship of FGF19/FGF21 and identify the structural basis underpinning the distinct proliferative feature of FGF19 compared with FGF21. In addition, these studies provide a road map for engineering FGF19 as a potential therapeutic candidate for treating diabetes and obesity.

Th17 central memory T cells are reduced by FTY720 in patients with multiple sclerosis

OBJECTIVE

FTY720 is a sphingosine 1-phosphate (S1P) receptor modulator that showed efficacy in phase II and III clinical trials in patients with multiple sclerosis (MS). FTY720 inhibits lymphocyte egress from secondary lymphoid organs into the peripheral circulation, thereby reducing the number of circulating naïve and central memory T cells, but not effector memory T cells in blood. Little is known to which of these memory T-cell subsets interleukin 17 (IL-17)-producing T cells (Th17 cells) belong, which are considered to be key mediators of inflammation in MS, and how they are affected by treatment with FTY720. In this study, we determined the phenotype and frequency of Th17 cells in blood of untreated, FTY720-treated, and interferon-beta (IFNbeta)-treated patients with MS and healthy donors.

METHODS

In a prospective observational study, circulating T cells were phenotypically characterized and Th17 cells enumerated in T-cell subsets ex vivo. Production of IL-17 upon activation and expression of the Th17-specific transcription factor RORC2 was assessed in vitro.

RESULTS

Th17 cells were found primarily within central memory T cells in all study populations. FTY720 treatment reduced blood central memory T cells, including RORC2+ and IL-17-producing T cells, by >90%. FTY720 did not per se affect IL-17 production when added to activated T cells in vitro.

CONCLUSION

Phenotypic Th17 cells are defined by a central memory T-cell phenotype. FTY720 reduces these Th17 cells in blood. This is presumably because central memory T cells are retained by FTY720 in secondary lymphoid organs.

Generation of novel long-acting globular adiponectin molecules

Adiponectin is an adipocyte-derived hormone that has been shown to play important roles in the regulation of glucose and energy homeostasis. It exists as homotrimers or complexes containing multiple homotrimer units in plasma. The recombinant adiponectin proteins have been difficult to produce, making it challenging for both research as well as potential therapeutic development. Here, we show a novel approach for the generation of globular adiponectin that involves linking three monomer sequences together in tandem to generate one continuous polypeptide, which we have termed single-chain globular adiponectin (sc-gAd). To improve the pharmacokinetic properties of sc-gAd further, we fused it to an Fc fragment. The combined effects of single-chain and Fc fusion improved the plasma half-life from less than 2 h to close to 2 weeks. Using adeno-associated virus as a delivery method, we demonstrate that Fc-sc-gAd improved both fasting glucose levels and the tolerance to a glucose challenge in ob/ob mice without changes in body weight. Therefore, our results demonstrated the feasibility of generating globular adiponectin trimers from a single polypeptide and a long-acting globular adiponectin that could serve as a starting point for adiponectin-based therapeutics. This novel approach could also be applied to other complement factor C1q family members; in particular, this opens the possibility to study the biological functions of precisely defined heterotrimers of various family members that had not been previously possible.

Exposure assessment at a PCDD/F contaminated site in Sweden--field measurements of exposure media and blood serum analysis

BACKGROUND, AIM, AND SCOPE

The main pathway for human exposure to the highly toxic polychlorinated-p-dioxins and polychlorinated furans [polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs)] is via dietary intake. Other exposure pathways may, however, be important in close proximity to point sources, such as wood preservation sites, where PCDD/F contaminated chlorophenols (CP) were previously used. In this study, a heavily PCDD/F contaminated CP saw mill site in Sweden was investigated. Human exposure through a broad spectrum of exposure pathways was assessed. Such studies are in demand since the question whether contaminated sites represent a current or future risk can only be answered by detailed site-specific risk assessments.

MATERIALS AND METHODS

Sampling of exposure media (soil, air, groundwater, raspberries, carrots, potatoes, grass, milk, eggs, and chicken fodder) was made. Exposure media concentrations and congener distribution patterns were used to investigate the mobilization of PCDD/Fs from soil to the environment and to calculate exposure levels for adults. Blood serum levels from site-exposed and control individuals were also analyzed.

RESULTS

Congener distribution patterns at the site were generally dominated by a specific marker congener (1234678-HpCDF), which is highly abundant in the polluted soil. The dioxin toxic equivalents (TEQ) concentrations were notably elevated as compared to national reference samples for most exposure media, and the marker congener was a major contributor to increased TEQ levels. There were also indications of soil-to-air volatilization of tetra- and penta-CDD/Fs. People who participated in the restoration of a contaminated building showed higher levels of 1234678-HpCDF compared to controls, and calculated exposure levels suggest that several site-specific exposure routes may be of importance for the daily intake of PCDD/F. CONCLUSIONS, RECOMMENDATIONS, AND PERSPECTIVES: Despite low mobility of higher chlorinated PCDD/Fs, these contaminants were transferred from the polluted soil to the surroundings and into human tissue. The extent of increased exposure from contaminated sites depends on the PCDD/F source strength of the soil, composition of the pollution, human activities, and dietary patterns of the residents. Impact from the contaminated soil on other exposure media was seen also for areas with low to moderate soil contamination. In the future, not only the levels of PCDD/F soil pollution but also the composition must be considered in risk assessments of contaminated sites.

FGF19-induced hepatocyte proliferation is mediated through FGFR4 activation

FGF19 and FGF21, unique members of the fibroblast growth factor (FGF) family, are hormones that regulate glucose, lipid, and energy homeostasis. Increased hepatocyte proliferation and liver tumor formation have also been observed in FGF19 transgenic mice. Here, we report that, in contrast to FGF19, FGF21 does not induce hepatocyte proliferation in vivo. To identify the mechanism for FGF19-induced hepatocyte proliferation, we explored similarities and differences in receptor specificity between FGF19 and FGF21. We find that although both are able to activate FGF receptors (FGFRs) 1c, 2c, and 3c, only FGF19 activates FGFR4, the predominant receptor in the liver. Using a C-terminal truncation mutant of FGF19 and a series of FGF19/FGF21 chimeric molecules, we determined that amino acids residues 38-42 of FGF19 are sufficient to confer both FGFR4 activation and increased hepatocyte proliferation in vivo to FGF21. These data suggest that activation of FGFR4 is the mechanism whereby FGF19 can increase hepatocyte proliferation and induce hepatocellular carcinoma formation.

Acute glucose-lowering and insulin-sensitizing action of FGF21 in insulin-resistant mouse models--association with liver and adipose tissue effects

Recombinant fibroblast growth factor (FGF)21 has antihyperglycemic, antihyperlipidemic, and antiobesity effects in diabetic rodent and monkey models. Previous studies were confined to measuring steady-state effects of FGF21 following subchronic or chronic administration. The present study focuses on the kinetics of biological actions of FGF21 following a single injection and on the associated physiological and cellular mechanisms underlying FGF21 actions. We show that FGF21 resulted in rapid decline of blood glucose levels and immediate improvement of glucose tolerance and insulin sensitivity in two animal models of insulin resistance (ob/ob and DIO mice). In ob/ob mice, FGF21 led to a 40-60% decrease in blood glucose, insulin, and amylin levels within 1 h after injection, and the maximal effects were sustained for more than 6 h despite the 1- to 2-h half-life of FGF21. In DIO mice, FGF21 reduced fasting blood glucose and insulin levels and improved glucose tolerance and insulin sensitivity within 3 h of treatment. The acute improvement of glucose metabolism was associated with a 30% reduction of hepatic glucose production and an increase in peripheral glucose turnover. FGF21 appeared to have no direct effect on ex vivo pancreatic islet insulin or glucagon secretion. However, it rapidly induced typical FGF signaling in liver and adipose tissues and in several hepatoma-derived cell lines and differentiated adipocytes. FGF21 was able to inhibit glucose release from H4IIE hepatoma cells and stimulate glucose uptake in 3T3-L1 adipocytes. We conclude that the acute glucose-lowering and insulin-sensitizing effects of FGF21 are potentially associated with its metabolic actions in liver and adipose tissues.

Environmental fate of the antiviral drug Tamiflu in two aquatic ecosystems

The antiviral drug Tamiflu (Oseltamivir Phosphate, OP), has been indicated by the World Health Organization as a first-line defense in case of an avian influenza pandemic. Recent studies have demonstrated that Oseltamivir Carboxylate (OC), the active metabolite of the prodrug OP, has the potential to be released into water bodies. The present laboratory study focused on basic processes governing the environmental fate of OC in surface water from two contrasting aquatic ecosystems of northern Italy, the River Po and the Venice lagoon. Results of this study confirmed the potential of OC to persist in surface water. However, addition of 5% of sediments resulted in rapid OC degradation. Estimated half-life of OC in water/sediment of the River Po was 15 days. After three weeks of incubation at 20 degrees C, more than 8% of (14)C-OC evolved as (14)CO(2) from water/sediment samples of the River Po and Venice lagoon. At the end of the 21-day incubation period, more than 65% of the (14)C-residues were recovered from the liquid phase of both Po and Venice water/sediment samples. OC was moderately retained onto coarse sediments from the two sites. In water/sediment samples of the River Po and Venice lagoon treated with (14)C-OC, more than 30% of the (14)C-residues remained water-extractable after three weeks of incubation. The low affinity of OC to sediments suggests that presence of sediments would not reduce its bioavailability to microbial degradation.

An acyl-ghrelin-specific neutralizing antibody inhibits the acute ghrelin-mediated orexigenic effects in mice

Ghrelin is a 28-amino acid peptide secreted mainly by the stomach. Acyl-ghrelin, which binds to and activates the growth hormone secretagogue receptor type 1a (GHS-R1a), is considered to be the active form for its orexigenic effects. It has been demonstrated that peripheral administration of ghrelin stimulates food intake and adiposity in rodents and humans. Accordingly, different approaches to antagonize ghrelin/GHS-R1a signaling have been pursued for the treatment of obesity. In the present study, we generated and characterized high-affinity anti-acyl ghrelin-specific monoclonal antibodies (mAbs). In vitro, the lead mAb (33A) displayed specific binding to acyl-ghrelin, with an estimated K(d) value < 100 pM. In recombinant receptor cell-based assays, 33A dose-dependently inhibited the ghrelin-mediated calcium signal, with an IC(50) of approximately 3.5 nM. In vivo, ghrelin dose-dependently stimulated food intake in mice, and this effect was fully blocked by a single injection of 33A. In a 4-week chronic study, 33A was shown to effectively bind to endogenous acyl-ghrelin; however, long-term administration of 33A did not affect food intake or body weight gain in a mouse model of diet-induced obesity. Our results indicate that peripheral neutralization of ghrelin can suppress appetite stimulated by a transient surge in ghrelin levels. The lack of long-term effects on body weight control by 33A suggests that compensatory mechanisms may contribute to the regulation of energy balance.

FGF21 N- and C-termini play different roles in receptor interaction and activation

Fibroblast growth factor-21 (FGF21) signaling requires the presence of beta-Klotho, a co-receptor with a very short cytoplasmic domain. Here we show that FGF21 binds directly to beta-Klotho through its C-terminus. Serial C-terminal truncations of FGF21 weakened or even abrogated its interaction with beta-Klotho in a Biacore assay, and led to gradual loss of potency in a luciferase reporter assay but with little effect on maximal response. In contrast, serial N-terminal truncations of FGF21 had no impact on beta-Klotho binding. Interestingly, several of them exhibited characteristics of partial agonists with minimal effects on potency. These data demonstrate that the C-terminus of FGF21 is critical for binding to beta-Klotho and the N-terminus is critical for fibroblast growth factor receptor (FGFR) activation.

Persistent immune responses in late infection and after treatment in experimental Schistosoma bovis infections in goats

This study explored host immune responses and their possible relationship to the anti-fecundity phenomenon in Schistosoma bovis-infected goats. The design comprised a primary infection with or without treatment at week (wk) 13, and with or without challenge at wk 36. Necropsy was performed at 36 or 52wk. Serum levels of anti-egg IgG, and anti-worm IgG and IgM, were measured by ELISA. In chronic infection, anti-worm antibodies stayed high, reflecting persisting worm burdens, whereas anti-egg IgG remained high despite minimized egg excretion. After treatment, anti-worm IgM and anti-egg IgG were minimized, but anti-worm IgG remained above the values of the uninfected controls. Histopathology showed lowered numbers of perioval granulomas in chronic infection and resolution of liver fibrosis with time, but intestinal lymphoplasmacytic perivasculitis and hepatic eosinophilic infiltrates were maintained at wk 52. Significant splenic plasmacytosis persisted after treatment. The results indicated that persistent immune responses, in chronically infected and in treated goats, may explain sustained worm fecundity depression at challenge infection.

C-terminal tail of FGF19 determines its specificity toward Klotho co-receptors

FGF19 subfamily proteins (FGF19, FGF21, and FGF23) are unique members of fibroblast growth factors (FGFs) that regulate energy, bile acid, glucose, lipid, phosphate, and vitamin D homeostasis in an endocrine fashion. Their activities require the presence of alpha or betaKlotho, two related single-pass transmembrane proteins, as co-receptors in relevant target tissues. We previously showed that FGF19 can bind to both alpha and betaKlotho, whereas FGF21 and FGF23 can bind only to either betaKlotho or alphaKlotho, respectively in vitro. To determine the mechanism regulating the binding and specificity among FGF19 subfamily members to Klotho family proteins, chimeric proteins between FGF19 subfamily members or chimeric proteins between Klotho family members were constructed to probe the interaction between those two families. Our results showed that a chimera of FGF19 with the FGF21 C-terminal tail interacts only with betaKlotho and a chimera with the FGF23 C-terminal tail interacts only with alphaKlotho. FGF signaling assays also reflected the change of specificity we observed for the chimeras. These results identified the C-terminal tail of FGF19 as a region necessary for its recognition of Klotho family proteins. In addition, chimeras between alpha and betaKlotho were also generated to probe the regions in Klotho proteins that are important for signaling by this FGF subfamily. Both FGF23 and FGF21 require intact alpha or betaKlotho for signaling, respectively, whereas FGF19 can signal through a Klotho chimera consisting of the N terminus of alphaKlotho and the C terminus of betaKlotho. Our results provide the first glimpse of the regions that regulate the binding specificity between this unique family of FGFs and their co-receptors.

Co-receptor Requirements for Fibroblast Growth Factor-19 Signaling

FGF19 is a unique member of the fibroblast growth factor (FGF) family of secreted proteins that regulates bile acid homeostasis and metabolic state in an endocrine fashion. Here we investigate the cell surface receptors required for signaling by FGF19. We show that betaKlotho, a single-pass transmembrane protein highly expressed in liver and fat, induced ERK1/2 phosphorylation in response to FGF19 treatment and significantly increased the interactions between FGF19 and FGFR4. Interestingly, our results show that alphaKlotho, another Klotho family protein related to betaKlotho, also induced ERK1/2 phosphorylation in response to FGF19 treatment and increased FGF19-FGFR4 interactions in vitro, similar to the effects of betaKlotho. In addition, heparin further enhanced the effects of both alphaKlotho and betaKlotho in FGF19 signaling and interaction experiments. These results suggest that a functional FGF19 receptor may consist of FGF receptor (FGFR) and heparan sulfate complexed with either alphaKlotho or betaKlotho.

Multivariate chemical mapping of antibiotics and identification of structurally representative substances

Antibiotics used in human and veterinary medicine have been found in samples from diverse environments in many parts of the world. To assess the environmental risks associated with them, data regarding their toxicity, occurrence, and fate are needed, but gathering such data is time-consuming and expensive. An efficient approach to address these difficulties would be to select a small subset of antibiotics with a wide variation in chemical characteristics, perform experimental tests on this subset, and then extrapolate the results to larger numbers of antibiotics, including the most potentially hazardous compounds. To assess the potential utility of such an approach, a set of 92 antibiotics for human use was studied and their structural properties were described with 24 chemical descriptors that included information on their steric, lipophilic, and electronic properties. Principal component analysis in combination with statistical experimental design was used to map the chemical diversity of the antibiotics and to select a small subset, a "training set", of 20 antibiotics. The chemical representativity of the training set was assessed in a quantitative structure-activity model established to predict ultimate biodegradation. The selected antibiotics showed to cover the chemical variation of the studied antibiotics and are suggested for use in future testing programs to assess antibiotics' fate and effects in the environment.

Immunomodulation of the hepatic egg granuloma in Schistosoma japonicum-infected pigs

Immunomodulation of perioval granulomas is a well-known phenomenon in schistosome-infected mice, but only little is known about granuloma modulation in other animal models of human schistosomiasis. In the present study, we explored immunomodulation of egg granulomas in the liver in a pig model of schistosomiasis japonica. Granuloma size was measured and T cells, B cells and IgG(+) plasma cells in granulomas were quantified in pigs at 9, 12 and 21 weeks post infection (wpi) with Schistosoma japonicum. Granulomas were largest at 9 wpi, had decreased significantly in size at 12 wpi and remained small at 21 wpi (9 vs. 12 and 21 wpi: P < 0.05). The size of granulomas containing mature and immature eggs, respectively, did not differ significantly. The density of T (CD3epsilon(+)) cells and IgG(+) plasma cells in granulomas was the same, irrespective of granuloma size and time points. B (CD79alpha(+)) cells were rare in granulomas. The results indicate that in pigs, S. japonicum egg granulomas in the liver are immunomodulated at an early stage of infection, and that not only mature but also immature eggs induce a marked granulomatous reaction in this species.

Consecutive pathological and immunological alterations during experimentally induced swine dysentery - a study performed by repeated endoscopy and biopsy samplings through an intestinal cannula

The development of intestinal lesions after inoculation with Brachyspira hyodysenteriae was followed by repeated endoscopy and biopsy sampling through a caecal cannula. Seven eight-week-old pigs were cannulated and inoculated, two were cannulated but not inoculated, and two pigs were inoculated but not cannulated. Endoscopy, biopsy, and blood sampling to determine SAA (serum amyloid A), haptoglobin, cortisol, and WBC counts were performed at scheduled time-points. At the third day of disease, endoscopy showed a hyperaemic, perturbed mucosa and excessive amount of mucus. Histologically, crypt hyperplasia, depletion of goblet cell mucus, and erosions were noted. Simultaneously, elevated acute phase proteins and circulating monocytes, and decreased number of intraepithelial CD3⁺ cells were observed. After five days the pigs recovered. Intestinal lesions were demarcated and interspersed among apparently normal mucosa and blood parameters returned to initial values. Endoscopy through an intestinal cannula made it possible to follow the development of intestinal alterations in vivo and describe the sequential events during the course of swine dysentery. The number of animals used in a study could thus be minimised and the precision of the experiment increased.

Treatment efficacy and regulatory host responses in chronic experimental Schistosoma bovis infections in goats

The aim of this study was to elucidate the regulatory responses and the long-term effect of praziquantel treatment in chronically Schistosoma bovis-infected West African Dwarf goats. Forty-two goats were used and the design comprised a primary infection followed by treatment at week 13, challenge infection at week 36 and termination at week 52. Dependent variables included clinico-pathological data, worm numbers, faecal and tissue egg counts, and gross pathology of the liver. The results showed that primary infections remained suppressed for up to 52 weeks and, although challenge infections imposed on 36-week-old primary infections established fully, the impairment of their egg production capacity provided protection against clinico-pathological consequences measured by body weight and haemoglobin levels. The study also confirmed a high efficacy (97.7%) of praziquantel for treatment of S. bovis infection in goats and showed that anthelminthic removal of primary infections does not interfere with the ability of the goat to elicit a marked resistance to a subsequent challenge infection. Although treated goats had more fibrous scarring of livers than untreated goats, no negative effects of liver lesions were reflected in weight gains of treated goats. This study provides strong evidence for the beneficial effects of anthelminthic treatment of young domestic stock as an element of treatment and preventive programmes.

Determination of antibiotic substances in hospital sewage water using solid phase extraction and liquid chromatography/mass spectrometry and group analogue internal standards

A method for determination of antibiotics in hospital sewage water has been developed and validated. Analogue internal standards for fluoroquinolones, sulfonamides, trimethoprim, beta-lactams (penicillins and cephalosporins), nitroimidazoles and tetracyclines were successfully used for calibration and shown to generally improve precision compared to external calibration. Matrix components caused ion suppression/enhancement effects during the MS detection for all analytes studied. Two effects were observed: general suppression and short-term variations in the MS response. In the hospital sewage water large temporal variations in the analyte concentration were observed during the course of the sampling period (seven grab samples in 13 h). Analyte concentrations varied within the following ranges (in microg l(-1)): ciprofloxacin, 3.6-101.0; metronidazole, 0.1-90.2; sulfamethoxazole, 0.4-12.8; ofloxacin, 0.2-7.6; trimethoprim, 0.6-7.6; and doxycycline, 0.6-6.7.

Experimental contagious caprine pleuropneumonia: a long term study on the course of infection and pathology in a flock of goats infected with Mycoplasma capricolum subsp. capripneumoniae

Contagious caprine pleuropneumonia (CCPP) is a major threat to goat farming in parts of Africa and Asia. It classically causes acute high morbidity and mortality early in infection, but little is known of its long term epizootiology and course. In this study, 10 goats were inoculated with Mycoplasma capricolum subsp. capripneumoniae (M. capripneumoniae) and then mixed with 15 goats for contact transmission. The disease course was monitored in each goat for 56-105 days, whereafter the goats were killed and necropsied. Varying features signifying infection occurred in altogether 17 goats (7 inoculated, 10 in-contact). Clinical signs were severe in 8 goats but no fatalities occurred. Only 6 goats had serum antibody titres against M. capripneumoniae in ELISA. Fourteen goats (5 inoculated, 9 in-contact) had chronic pleuropulmonary lesions compatible with CCPP at necropsy and 7 of those showed M. capripneumoniae antigen in the lung by immunohistochemistry. Neither cultivation nor PCR tests were positive for the agent in any goat. The results indicate that the clinical course of CCPP in a flock may be comparatively mild, M. capripneumoniae-associated lung lesions may be present at a late stage of infection, and chronic infection may occur without a significant serological response.

IFNbeta lowers MMP-9/TIMP-1 ratio, which predicts new enhancing lesions in patients with SPMS

OBJECTIVE

To 1)determine serum levels of matrix metalloproteinase-2 (MMP-2), MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), and TIMP-2 in patients with secondary progressive (SP) MS; 2)determine the relationship between these serum levels and MRI activity; and 3) evaluate the effect of interferon (IFN) therapy on these measures.

BACKGROUND

High serum levels of MMP-9 and low levels of TIMP-1 predict the appearance of new gadolinium-enhancing (Gd+) lesions in relapsing-remitting (RR) MS.

METHODS

Monthly Gd+ brain MRI and measures of serum MMP-2, MMP-9, TIMP-1, and TIMP-2 at 3-month intervals were performed for up to 3 years in 33 patients with SPMS participating in a phase III study of IFNbeta-1b.

RESULTS

Patients who developed new Gd+ lesions had higher levels of MMP-9 than patients who did not develop Gd+ lesions (median 351 vs 226 ng/mL, p = 0.049). The ratio of MMP-9/TIMP-1 predicted new Gd+ lesion on the concurrent scan (OR = 2.23, 95% CI 0.99 to 4.99, p = 0.052) and on the following scan (OR = 2.16, 95% CI 1.01 to 4.63, p = 0.048), whereas levels of MMP-2/TIMP-2 did not. Median levels of TIMP-1 were higher and MMP-9 trended lower for IFNbeta compared to placebo recipients (TIMP-1: 1,450 vs 1,185 ng/mL, p = 0.024; MMP-9: 225 vs 339 ng/mL, p = 0.081). IFNbeta did not influence levels of MMP-2 and TIMP-2.

CONCLUSION

The ratio of MMP-9/TIMP-1 may predict MRI activity in SPMS. The effect of IFNbeta-1b in MS, as measured by reduction in new Gd+ lesions, may be partly explained by altering MMP-9/TIMP-1 ratio.

Intestinal cannulation: model for study of the midgut of the pig

PURPOSE

To develop a pig model that would enable repeated biopsy specimen collection and endoscopic monitoring of the gut. This would increase precision of the experiment and reduce the number of experimental animals required.

METHODS

Six 10-week-old Yorkshire pigs underwent surgery, and a cannula was inserted in the cecum. Two pigs served as non-operated controls. The health status of the animals was monitored by clinical, hematologic, and biochemical examinations and by studies of gut motility and microbial flora. The experimental period lasted for eight weeks and approximately 45 biopsy specimens were obtained from each animal.

RESULTS

Repeated endoscopy was performed and biopsy specimens were taken. Adverse effects on the animal's health were not apparent, and differences were not evident in transit time of digesta or in diversity of the gut microbial flora. After surgery there was a transient increase in the concentrations of haptoglobin, serum amyloid A, and plasma cortisol, and in body temperature and white blood cell count.

CONCLUSIONS

It is possible to use an intestinal cannula in the cecum both for endoscopy and biopsy specimen collection. The procedures did not influence health status of the pigs, nor alter gut function. The method will be useful in experimental infection studies as well as in other physiologic investigations.