Super-resolution and apodization with discrete adaptive optics.

High-resolution imaging is of great importance in various fields. The use of pupil phase-only filters (PPF) exceeds the diffraction limit of the imaging system in a simple way. When dealing with distorted wavefronts, however, PPF require that aberrations be compensated for. In this paper, we introduce a novel technique consisting of the use of discrete adaptive optics with PPFs so that the compensating device implements the PPF at the same time. Analysis of the theory for point spread function reshaping using PPFs has enabled us to develop a new approach to characterizing apodizing filters. A validation experiment has been carried out, the first of its kind to our knowledge, in which a number of PPFs were combined with two levels of compensation. Our experimental results are discussed.

Application of different alkaline materials as polluted soil amendments: A comparative assessment of their impact on trace element mobility and microbial functions.

Treatment with chemical amendments is among the best techniques to remediate soils highly polluted with trace elements. The use of waste-derived products has several advantages in this regard, mainly in terms of reducing process costs and conserving natural resources. In this study, the performance of the synthetic zeolite NaP1 derived from coal combustion fly ash (SZ) and the by-product generated from the processing of aluminum salt slags (BP) was evaluated with this aim in comparison to calcite (CC). For this purpose, mine soils polluted with Zn, Cd, and Pb were amended under controlled laboratory conditions with different doses (0%, 1%, 2%, 5%, and 10%) of SZ, BP, or CC, and their impact on trace element mobility and microbial functions was evaluated. Specifically, the mobile and mobilizable trace element pools, basal soil respiration, and different enzyme activities were analyzed. Both SZ and BP performed better than CC in the immobilization of trace elements, reaching, respectively, mobility decreases up to 89-94% and 66-87% when applied at a dose of 10%. These amendments reduced the mobile trace element pool by precipitating them as acid-soluble precipitates and/or retaining them in the reducible fraction of soils. The alkaline nature of these materials and the concomitant increase in soil pH caused by their application mainly accounted for this behavior. Additionally, soil microbial functionality improved after amendment, especially in the case of SZ, as shown by dehydrogenase and alkaline phosphatase activities, which significantly increased (p < 0.05) up to 536% and 48%, respectively. Therefore, applying SZ or BP as soil amendments can significantly decrease the mobile trace element contents of heavily polluted soils without negatively affecting soil quality, thus facilitating plant growth to revegetate and reclaim degraded spaces.

Arsenic distribution in a pasture area impacted by past mining activities.

Former mine exploitations entail a serious threat to surrounding ecosystems as after closure of mining activities their unmanaged wastes can be a continuous source of toxic trace elements. Quite often these mine sites are found within agricultural farming areas, involving serious hazards as regards product (feed/food) quality. In this work a grazing land impacted by the abandoned mine exploitation of an arsenical deposit was studied so as to evaluate the fate of arsenic (As) and other trace elements and the potential risks involved. With this aim, profile soil samples (0-50cm) and pasture plant species (Agrostis truncatula, Holcus annus and Leontodon longirostris) were collected at different distances (0-100m) from the mine waste dump and analyzed for their trace element content and distribution. Likewise, plant trace element accumulation from impacted grazing soils and plant trace element translocation were assessed. The exposure of livestock grazing animals to As was also evaluated, establishing its acceptability regarding food safety and animal health. International soil guideline values for As in grazing land soils (50mgkg-1) resulted greatly exceeded (up to about 20-fold) in the studied mining-affected soils. Moreover, As showed a high mobilization potential under circumstances such as phosphate application or establishment of reducing conditions. Arsenic exhibited relatively high translocation factor (TF) values (up to 0.32-0.89) in pasture plant species, reaching unsafe concentrations in their above-ground tissues (up to 32.9, 16.9 and 9.0mgkg-1 in Agrostis truncatula, Leontodon longirostris and Holcus annus, respectively). Such concentrations represent an elevated risk of As transfer to the high trophic-chain levels as established by international legislation. The limited fraction of arsenite found in plant roots should play an important role in the relatively high As root-to-shoot translocation shown by these plant species. Both soil ingestion and pasture intake resulted important entrance pathways of As into livestock animals, showing quite close contribution levels. The cow acceptable daily intake (ADI) of As regarding food safety was surpassed in some locations of the study area when the species Agrostis truncatula was considered as the only pasture feed. Restrictions in the grazing use of lands with considerable As contents where this plant was the predominant pasture species should be established in order to preserve food quality. Therefore, the exposure of livestock animals to As via both soil ingestion and pasture consumption should be taken into account to establish the suitability of mining-impacted areas for gazing.

A comparative study on the influence of different organic amendments on trace element mobility and microbial functionality of a polluted mine soil.

A mine soil heavily polluted with zinc and cadmium was employed to evaluate the capacity of organic amendments of different origin to simultaneously reduce soil trace element mobility and enhance soil microbial functionality. With this aim, four organic products, namely olive processing solid waste (OPSW), municipal solid waste compost (MSWC), leonardite and peat, were applied individually at different doses (0, 1, 2 and 5%) to mine soil under controlled laboratory conditions. Extraction studies and analysis of soil microbiological parameters (basal soil respiration and dehydrogenase, ß-glucosidase, urease, arylsulfatase and acid and alkaline phosphatase activities) were performed to assess the effect of such amendments on soil restoration. Their ability to decrease mine soil mobile trace element contents followed the sequence MSWC > OPSW > peat > leonardite, with the former achieving reduction levels of 78 and 73% for Zn and Cd, respectively, when applied at a dose of 5%. This amendment also showed a good performance to restore soil microbial functionality. Thus, basal soil respiration and dehydrogenase, urease and alkaline phosphatase activities experienced increases of 187, 79, 42 and 26%, respectively, when mine soil was treated with 5% MSWC. Among tested organic products, MSWC proved to be the best amendment to perform both the chemical and the microbial soil remediation.

Survival and neurological status after out-of-hospital cardiac arrest in the pediatric population in Andalusia.

OBJECTIVE: Little is known about the evolution and long-term neurological status of pediatric patients who survive out-of-hospital cardiac arrest. Our aim is to describe long-term survival and neurological status. DESIGN: Retrospective observational study, based on the Andalusian Register of out-of-hospital Cardiac Arrest. SETTING: Pre-hospital Care. PATIENTS: The study included patients aged 0-15 years between January 2008 and December 2012. INTERVENTIONS: Patients follow up. VARIABLES: Prehospital and hospital care variables were analyzed and one-year follow-up was performed, along with a specific follow-up of survivors in June 2014. RESULTS: Of 5069 patients included in the register, 125 (2.5%) were aged ≤15 years. Cardiac arrest was witnessed in 52.8% of cases and resuscitation was performed in 65.6%. The initial rhythm was shockable in 7 (5.2%) cases. Nearly half (48.8%) the patients reached the hospital alive, of whom 20% did so while receiving resuscitation maneuvers. Only 9 (7.2%) patients survived to hospital discharge; 5 showed ad integrum recovery and 4 showed significant neurological impairment. The 5 patients with complete recovery continued their long-term situation. The remaining 4 patients, although slight improvement, were maintained in situation of neurological disability. CONCLUSIONS: Survival after out-of-hospital cardiac arrest in pediatric patients was low. The long-term prognosis of survivors with good neurological recovery remains, although improvement in the rest was minimal.

Culturable heterotrophic bacteria associated with healthy and bleached scleractinian Madracis decactis and the fireworm Hermodice carunculata from the remote St. Peter and St. Paul Archipelago, Brazil.

We report on the first characterization of the culturable heterotrophic bacteria of the scleractinian Madracis decactis. In addition, we characterized the culturable bacteria associated with the fireworm Hermodice carunculata, observed predating partially bleached coral colonies. Our study was carried out in the remote St. Peter and St. Paul Archipelago (SPSPA), Mid-Atlantic Ridge, Brazil. We constituted a 403 isolates collection and subsequently characterized it by means of pyrH and 16S rRNA partial sequences. We identified Photobacterium, Bacillus, and Vibrio species as members of the culturable microbiota of healthy M. decactis. V. campbellii, V. harveyi, V. communis, and V. maritimus were the most commonly found Vibrio species in healthy corals, representing more than 60 % of all vibrio isolates. Most of the vibrios isolated from the fireworm's tissues (n = 143; >90 %) were identified as V. shiloi. However, we did not recover V. shiloi from bleached M. decactis. Instead, we isolated V. communis, a novel Photobacterium species, Bacillus, Kocuria, and Pseudovibrio, suggesting a possible role of other facultative anaerobic bacteria and/or environmental features (such as water quality) in the onset of bleaching in SPSPA's M. decactis.

The Norwegian Healthier Goats program--modeling lactation curves using a multilevel cubic spline regression model.

In 2001, the Norwegian Goat Health Service initiated the Healthier Goats program (HG), with the aim of eradicating caprine arthritis encephalitis, caseous lymphadenitis, and Johne's disease (caprine paratuberculosis) in Norwegian goat herds. The aim of the present study was to explore how control and eradication of the above-mentioned diseases by enrolling in HG affected milk yield by comparison with herds not enrolled in HG. Lactation curves were modeled using a multilevel cubic spline regression model where farm, goat, and lactation were included as random effect parameters. The data material contained 135,446 registrations of daily milk yield from 28,829 lactations in 43 herds. The multilevel cubic spline regression model was applied to 4 categories of data: enrolled early, control early, enrolled late, and control late. For enrolled herds, the early and late notations refer to the situation before and after enrolling in HG; for nonenrolled herds (controls), they refer to development over time, independent of HG. Total milk yield increased in the enrolled herds after eradication: the total milk yields in the fourth lactation were 634.2 and 873.3 kg in enrolled early and enrolled late herds, respectively, and 613.2 and 701.4 kg in the control early and control late herds, respectively. Day of peak yield differed between enrolled and control herds. The day of peak yield came on d 6 of lactation for the control early category for parities 2, 3, and 4, indicating an inability of the goats to further increase their milk yield from the initial level. For enrolled herds, on the other hand, peak yield came between d 49 and 56, indicating a gradual increase in milk yield after kidding. Our results indicate that enrollment in the HG disease eradication program improved the milk yield of dairy goats considerably, and that the multilevel cubic spline regression was a suitable model for exploring effects of disease control and eradication on milk yield.

Antimicrobial activity of binary combinations of natural and synthetic phenolic antioxidants against Enterococcus faecalis.

This study investigated the antimicrobial activity of 3 natural (thymol, carvacrol, and gallic acid) and 2 synthetic [butylated hydroxyanisole (BHA) and octyl gallate] phenolic compounds, individually and in binary combinations, on 4 dairy isolates of Enterococcus faecalis with different virulence factors (ß-hemolytic, gelatinase, or trypsin activities; acquired resistance to erythromycin or tetracycline; and natural resistance to gentamicin). A checkerboard technique and a microdilution standardized method were used. All compounds individually tested exhibited antimicrobial activity against E. faecalis, with minimal inhibitory concentrations (MIC) ranging from 30 µg/mL (octyl gallate) to 3,150 µg/mL (gallic acid), although no significant differences were detected among strains to each phenolic compound. Carvacrol in combination with thymol or gallic acid, and gallic acid combined with octyl gallate showed partial synergistic inhibition of all E. faecalis strains. The most effective combinations were thymol+carvacrol and gallic acid+octyl gallate, as the MIC for each of these compounds was reduced by 67 to 75% compared with their respective individual MIC. These results highlight the possibility of using combinations of these phenolic compounds to inhibit the growth of potential virulent or spoilage E. faecalis strains by reducing the total amount of additives used in dairy foods.

The community pharmacy model for colorectal cancer screening: Policy insights from a national programme.

BACKGROUND: In Italy, a recent national project has expanded local collaboration between colorectal (CRC) screening programmes and pharmacies to the national level. OBJECTIVE: The objective of this study is to provide an overview of the existing agreements between regional authorities and pharmacy owners in Italy regarding CRC screening programmes, to make internationally available the most qualifying elements of the collaboration. METHODS: We analyzed the agreements, in force on 01/08/2021, arranged between the Regions and their respective pharmacy owners, describing the process phases addressed such as the faecal occult blood test pathway and supplementary activities provided by the pharmacies together with the CRC screening kit delivery. RESULTS: Agreements were received from 18 Regions (86% of the total). The amount of money paid for each kit varies a lot, with a range from 0 to 18 EUR. The number of process phases covered by the agreements ranged from a maximum of 16 (out of 18) to a minimum of 0. The processes most frequently covered were the supply/delivery of kits and education/awareness of CRC screening (68.8%). Less covered processes were warehouse management and awareness of other healthcare initiatives (12.5%), and delivery of preparation for intestinal cleansing (6.3%). CONCLUSIONS: Arrangements between pharmacies and CRC screening programmes in Italy vary widely and lack a unified model. Collaboration quality standards should be set at the national/international level.

Factory neovessels: engineered human blood vessels secreting therapeutic proteins as a new drug delivery system.

Several works have shown the feasibility of engineering functional blood vessels in vivo using human endothelial cells (ECs). Going further, we explored the therapeutic potential of neovessels after gene-modifying the ECs for the secretion of a therapeutic protein. Given that these vessels are connected with the host vascular bed, we hypothesized that systemic release of the expressed protein is immediate. As a proof of principle, we used primary human ECs transduced with a lentiviral vector for the expression of a recombinant bispecific alphaCEA/alphaCD3 antibody. These ECs, along with mesenchymal stem cells as a source of mural cells, were embedded in Matrigel and subcutaneously implanted in nude mice. High antibody levels were detected in plasma for 1 month. Furthermore, the antibody exerted a therapeutic effect in mice bearing distant carcinoembryonic-antigen (CEA)-positive tumors after inoculation of human T cells. In summary, we show for the first time the therapeutic effect of a protein locally secreted by engineered human neovessels.

Multiple negative elements in a gene that codes for an extracellular matrix protein, collagen X, restrict expression to hypertrophic chondrocytes.

During skeletal development, chondrocytes go through several stages of differentiation. The last stage, chondrocyte hypertrophy, occurs in areas of endochondral ossification. Mature hypertrophic chondrocytes differ from immature chondrocytes in that they become postmitotic, increase their cellular volume up to eightfold, and synthesize a unique set of matrix molecules. One such molecule is a short collagenous protein, collagen X. Previous studies have shown that collagen X is not expressed by other cell types and that its specific expression in hypertrophic chondrocytes is controlled by transcriptional mechanisms. To define these mechanisms, plasmid constructs containing the chicken collagen X gene promoter and 5' flanking regions fused to a reporter gene (chloramphenicol acetyl transferase, CAT) were transfected into primary cultures of collagen X-expressing and nonexpressing cells. A construct containing a short (558 bp) promoter exhibited high levels of CAT activity in all cell types (fibroblasts, immature, and hypertrophic chondrocytes). Adding a 4.2-kb fragment of 5' flanking DNA to this construct resulted in a dramatic reduction of CAT activity in fibroblasts and immature chondrocytes, but had no effect in hypertrophic chondrocytes. Addition of three subfragments of the 4.2-kb fragment to the initial construct, either individually or in various combinations, showed that all subfragments reduced CAT activity somewhat in non-collagen X-expressing cells, and that their effects were additive. Unrelated DNA had no effect on CAT activity. The results suggest that multiple, diffuse upstream negative regulatory elements act in an additive manner to restrict transcription of the collagen X gene to hypertrophic chondrocytes.

Beach nourishment using sediments from relict sand deposit: Effects on subtidal macrobenthic communities in the Central Adriatic Sea (Eastern Mediterranean Sea-Italy).

Nowadays nourishment is the most popular shore reconstruction strategy to counteract erosion of coastal areas. Sediments used for nourishment can have terrestrial or marine origin. This study analysed the effects of nourishment with relict sand on the subtidal macrobenthic communities and on the surface sediment at 7 sites of the Marche Region (Central Adriatic Sea, Italy). Samples for biological and physical analyses were collected in each site before and after nourishment. One year after nourishment the presence of the relict sands used for the replenishment is still visible in the sediment of each site. In the same period macrobenthic communities are characterised by the dominance of a few species able to avoid burial and suffocation phenomena, showing a low variability respect to the communities present before.

Acquired haemophilia A as a secondary autoimmune disease after alemtuzumab treatment in multiple sclerosis: A case report.

Alemtuzumab is a highly effective monoclonal antibody for the treatment of multiple sclerosis (MS). During the immune reconstitution following the use of this treatment severe secondary autoimmune diseases (SADs) can develop. We present the case of a patient affected by active MS who failed to achieve disease control with several disease-modifying drugs and was thereafter successfully treated with alemtuzumab, obtaining no evidence of disease activity and a high quality of life. Twenty months after the first infusion of alemtuzumab the patient developed acquired haemophilia A (AHA), a treatable but potentially lifethreatening condition that should be considered a possible SADs associated to this drug. In order to allow an early diagnosis and to prevent possible complications of AHA, routine coagulation tests (prothrombin time and activated partial thromboplastin time) should be included in the laboratory serological monitoring of patients treated with alemtuzumab.

Efficacy of an information system addressed to nursing staff for diminishing contaminated blood cultures: a blind clinical trial.

OBJECTIVE: Evaluate the efficacy of an information system addressed to nursing staff to lower the blood culture contamination rate. METHODS: A blind clinical trial was conducted at Internal Medicine and Emergency Departments during 2011. After following a reeducation program in BC extraction, participants were randomly selected in a 1:1 ratio. Every participant of the experimental group was informed of each worker's individual performance; whereas the control group was only informed of the global results. RESULTS: A total of 977 blood extractions were performed in 12 months. Blood culture contamination rate was 7.5%. This rate was higher in the Emergency Department than in Internal Medicine (10% vs. 3.8%; p=0.001). Factors associated with the higher risk of contamination were, in the univariate analysis, the extraction through a recently implanted blood route and the time of professional experience, while those associated with a lower risk were the extraction in Internal Medicine and through a butterfly needle. On multivariate analysis, extraction through a recently placed access was an independent risk factor for an increased contamination rate (OR 2.29; 95%CI 1.18-4.44, p=0.014), while individual information about the blood culture results (OR 0.11; 95%CI 0.023-0.57; p=0.008), and more than 9 years of professional experience were asso-ciated with fewer contaminations (OR 0.30; 95%CI 0.12-0.77; p=0.012). In the intervention group the contamination rate diminished by a 26 %. CONCLUSIONS: Drawing blood cultures through a recently taken peripheral venous access increased their risk of contamination. The intervention informing the nurse staff of the contamination rate is effective to decrease it.

Trace element levels in an area impacted by old mining operations and their relationship with beehive products.

The environmental status of an area impacted by Roman mining activities was assessed in order to establish the current risks posed by such old mine emplacements. For this purpose, soil samples were collected throughout the mining area and analysed for their total, mobile and mobilizable trace element (As, Cd, Mo, Sb and Zn) contents. Additionally, beehive products (honey and pollen) were also sampled and evaluated for their use as environmental indicators of the area. The results obtained were compared with those from a control non-polluted area. The mine soils presented slightly increased levels of Cd and Sb (about 2- to -3-fold their normal soil concentrations), whereas the enrichment of As reached considerable levels, with concentrations almost ten-fold of those considered the threshold for causing toxicity. Leachable As contents exhibited very high values (1.2-21.9mgkg-1), indicating the need for risk attenuation measures. All trace elements were mainly partitioned in the soil residual fraction, especially Mo (76-99%) and Sb (61-91%). Significant partitioning levels were also found in the reducible fraction of As (up to 35%) and Cd (up to 38%), and in the oxidizable fraction of Mo (up to 23%). The reducible pool of As was particularly relevant due to the eventual mobilization of this element under reducing conditions. Among the beehive products tested, honey proved not to be useful as an environmental indicator, whereas pollen showed great potential as an indicator when the contamination levels were moderate to high.

The control of bovine viral diarrhoea virus in Europe: today and in the future.

This paper summarises the views of a European group of scientists involved in the control of bovine viral diarrhoea virus (BVDV), as part of a European Union Thematic Network. The group concludes that the technical tools and the knowledge needed to eradicate BVDV are at hand, as proven by successful national control schemes in several European countries. A generic model for BVDV control is presented, which includes biosecurity, elimination of persistently infected animals and surveillance as central elements. These elements are termed 'systematic', in contrast to control efforts without clear goals and surveillance to evaluate progress. The network concludes that a systematic approach is needed to reach a sustainable reduction in the incidence and prevalence of BVDV in Europe. The role of vaccines in systematic control programmes is considered as an additional biosecurity measure, the effect of which should be evaluated against cost, safety and efficacy. It is also concluded that active participation by farmers' organisations is a strong facilitator in the process that leads up to the initiation of control, and that public funding to support the initiation of organised BVD control programmes can be justified on the basis of expected wider societal benefits, such as animal welfare and reduction in the use of antibiotics. If applied successfully, the focus on biosecurity in systematic BVD control programmes would also reduce the risk of the introduction and spread of other epizootic and zoonotic agents, thereby improving both cattle health and welfare in general, as well as increasing the competitiveness of the cattle industry.

Brain-derived neurotrophic factor protects neuroblastoma cells from vinblastine toxicity.

Brain-derived neurotrophic factor (BDNF) and its receptors are necessary for the survival and development of many neuronal cells. Because BDNF and TrkB are expressed in many poor-prognosis neuroblastoma (NB) tumors, we evaluated the role of BDNF in affecting sensitivity to chemotherapeutic agents. We investigated the effects of activation of the BDNF-TrkB signal transduction pathway in two NB cell lines, 15N and SY5Y. 15N cells lack the high-affinity receptor p145TrkB and express BDNF; 15N cells were used along with 15N-TrkB cells, a subline transfected with a TrkB expression vector. In cytotoxicity assays, 15N-TrkB cells were consistently 1.4-2 fold more resistant to vinblastine than 15N cells. Drug accumulation assays showed a 50% reduction in[3H]vinblastine accumulation in 15N-TrkB cells compared with control 15N cells. Addition of 30 ng/ml BDNF resulted in a reduction to 46% of control in 15N cells and a reduction to 28% of control in 15N-TrkB cells. SY5Y cells were chosen as a second model because they lack both endogenous BDNF and TrkB expression. p145TrkB expression is induced by 1 nM retinoic acid. Vinblastine accumulation was not significantly affected by 1 nM retinoic acid in SY5Y cells. Addition of 30 ng/ml BDNF decreased [3H]vinblastine accumulation to 58% of control in SY5Y cells and decreased [3H]vinblastine accumulation to 62% of control in TrkB-expressing SY5Y cells. Although an increase in BDNF expression in seen in multidrug-resistant sublines of SY5Y and BE(2)-C NB cells, the protective effect of BDNF in vinblastine toxicity may be unrelated to mdr-1, because the activity of other agents transported by P-glycoprotein was not affected. There was no increase in mdr-1 expression in 1 nM RA SY5Y cells and 15N-TrkB cells, as assessed by Northern blot analysis. In addition to the effects of BDNF on vinblastine cytotoxicity and accumulation, there was an inhibition in the ability of vinblastine to depolymerize tubulin in BDNF-treated cells. Thus, BDNF and TrkB may partially rescue NB cells from vinblastine toxicity and thereby may contribute to a more chemoresistant phenotype.

Welfare effects of a disease eradication programme for dairy goats.

The Norwegian dairy goat industry has largely succeeded in controlling caprine arthritis encephalitis (CAE), caseous lymphadenitis (CLA) and paratuberculosis through a voluntary disease eradication programme called Healthier Goats (HG). The aim of this study was to apply an on-farm welfare assessment protocol to assess the effects of HG on goat welfare. A total of 30 dairy goat farms were visited, of which 15 had completed disease eradication and 15 had not yet started. Three trained observers assessed the welfare on 10 farms each. The welfare assessment protocol comprised both resource-based and animal-based welfare measures, including a preliminary version of qualitative behavioural assessments with five prefixed terms. A total of 20 goats in each herd were randomly selected for observations of human-animal interactions and physical health. The latter included registering abnormalities of eyes, nostrils, ears, skin, lymph nodes, joints, udder, claws and body condition score. For individual-level data, robust clustered logistic regression analyses with farm as cluster variable were conducted to assess the association with disease eradication. Wilcoxon rank-sum tests were used for comparisons of herd-level data between the two groups. Goats with swollen joints (indicative of CAE) and enlarged lymph nodes (indicative of CLA) were registered on 53% and 93% of the non-HG farms, respectively, but on none of the HG farms. The only other health variables with significantly lower levels in HG herds were skin lesions (P=0.008) and damaged ears due to torn out ear tags (P<0.001). Goats on HG farms showed less fear of unknown humans (P=0.013), and the qualitative behavioural assessments indicated that the animals in these herds were calmer than in non-HG herds. Significantly more space and lower gas concentrations reflected the upgrading of buildings usually done on HG farms. In conclusion, HG has resulted in some welfare improvements beyond the elimination of infectious diseases. The protocol was considered a useful tool to evaluate the welfare consequences of a disease eradication programme. However, larger sample sizes would increase the reliability of prevalence estimates for less common conditions and increase the power to detect differences between the groups. Despite the obvious link between disease and suffering, this aspect is rarely taken into account in the evaluation of disease control programmes. We therefore propose that welfare assessment protocols should be applied to evaluate the merits of disease control or eradication programmes in terms of animal welfare.

A study of the allosteric kinetics of Phycomyces pyruvate kinase as judged by the effect of L-alanine and fructose 1,6-bisphosphate.

The influence of fructose 1,6-bisphosphate and L-alanine on the kinetics of pyruvate kinase (ATP:pyruvate O2-phosphotransferase, EC 2.7.1.40) from Phycomyces blakesleeanus NRRL 1555 (-) was studied at pH 7.5. By addition of fructose 1,6-bisphosphate the sigmoid kinetics with respect to phosphoenol pyruvate and Mg2+ were abolished and the velocity curves became hyperbolic. In the presence of L-alanine the positive homotropic cooperativity with respect to phosphoenol pyruvate increased with Hill coefficient values close to 4, while the sigmoid kinetics with respect to Mg2+ became hyperbolic. Fructose 1,6-bisphosphate overcomes the inhibition produced by L-alanine, the antagonism between phosphoenol pyruvate and L-alanine also being evident. Inhibition has been found at high Mg2+ concentrations, compatible with the binding of the magnesium ions to an inactive conformational state of the enzyme. The data were analysed on the basis of the two-states concerted-symmetry model of Monod, Wyman and Changeux, and the parameters of the model were calculated. Phosphoenol pyruvate and fructose 1,6-bisphosphate appeared to show exclusive binding to the active conformational state (R), whereas magnesium ions bind preferentially, by a factor of 45, to the R state. L-Alanine binds more readily to the inactive T state of the enzyme.