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Fusarium ear rot of corn (Zea mays L.) is associated with feeding damage from the European corn borer (ECB), Ostrinia nubilalis Hubner, and the corn earworm (CEW), Helicoverpa zea Boddie. Specific transformation events encoding for Cry1Ab protein from Bacillus thuringiensis Berliner (Bt) may reduce Fusarium ear rot and fumonisin concentration in grain by minimizing damage from certain insects. The objective of this study was to determine if effects from Cry1Ab protein in kernels and silks on fumonisin concentration in grain vary depending on the genotype of the hybrid or the predominant insect species. Four Bt corn hybrids and their corresponding nontransgenic, near-isogenic hybrids were compared for ear rot severity and fumonisin concentration in grain in four environments. Treatments included inoculation with F. verticillioides (Sacc.) Nirenb. (Syn = F. moniliforme J. Sheld.) and F. proliferatum (Matsushima) Nirenb., infestation with ECB larvae, infestation with CEW larvae, and controls. Cry1Ab protein from the Mon810 transformation event was associated with reduced ear rot severity when hybrids were not inoculated with Fusarium spp., regardless of whether hybrids were infested or not infested with insects. Cry1Ab protein was associated with reduced fumonisin concentration in grain when ECB was the predominant insect, but not when CEW was the predominant insect. Cry1Ab protein was not associated with reduced fumonisin concentration in grain for the most resistant hybrid pair in this study. Results suggest that Bt hybrids can reduce fumonisin concentration in grain during seasons when ECB is favored, but not during seasons when CEW is favored. Hybrid genotype was an important factor in reducing fumonisin concentration in grain.

Colisepticaemia is a major health and economic concern for the mink industry, yet little information is available about the Escherichia coli that cause this disease. In this study, 40 E. coli, isolated from mink clinically diagnosed with colisepticaemia that had been submitted to the North Dakota State University Veterinary Diagnostic Laboratory, were randomly selected for characterization. These isolates were serotyped and screened for resistance to 18 antimicrobials, possession of transmissible R plasmids, and the presence of several virulence traits or genes using bioassays or the polymerase chain reaction. Several serotypes were identified that have previously been associated with septicaemia in other animal species. The majority of the isolates exhibited multiple antimicrobial resistance phenotypes. Common resistance phenotypes observed included those to tetracycline, sulfamethoxazole, streptomycin, ampicillin and kanamycin. Several of the isolates that could be studied by conjugation contained transmissible R plasmids coding for multiple antimicrobial resistance phenotypes. About half of the isolates produced colicin; all produced enterobactin: and all but one-quarter produced aerobactin. None of the isolates tested produced enterohaemolysin, and one-fifth were considered to be beta haemolytic. About half appeared to contain the gene encoding cytotoxic necrotizing factor-1; three contained the gene encoding EAE, but none appeared to contain the genes coding for LT, Sta/b, SLT-I/II or CNF-II toxins or K99 antigen. Approximately one-third of the isolates elaborated capsule. The results show that the E. coli isolates implicated in mink colisepticaemia possess similar virulence traits and antimicrobial resistance phenotypes to those associated with diarrhoeal diseases in food animals.

A guideline on the responsible and prudent use of antimicrobials in animal husbandry has been developed by the Ad hoc Group of experts on antimicrobial resistance, created by the Office International des Epizooties. The objectives of responsible use are to maintain antibiotic efficacy, to avoid the dissemination of resistant bacteria or resistance determinants and to avoid the exposure of humans to resistance through food. The guideline attributes a central role to the competent authorities responsible for granting marketing authorizations for antimicrobial substances. Requirements before and after granting of marketing authorizations are defined. Important aspects include the control of the pharmaceutical product quality and the therapeutic efficacy, the assessment of the selection pressure, the protection of the environment, specific and non-specific antimicrobial resistance surveillance. The guideline is also addressed to the veterinary pharmaceutical industry, veterinary practitioners, dispensing pharmacists and farmers. The respective roles and responsibilities of these groups are defined.

A guideline on the harmonisation of national antimicrobial resistance monitoring and surveillance programmes in animals and animal-derived foods has been developed by the Ad hoc Group of experts on antimicrobial resistance of the Office International des Epizooties. The objective of the guideline is to allow the generation of comparable data from various national surveillance and monitoring systems in order to compare the situations in different regions or countries and to consolidate results at the national, regional and international level. Definitions of surveillance and monitoring are provided. National systems should be able to detect the emergence of resistance, and to determine the prevalence of resistant bacteria. The resulting data should be used in the assessment of risks to public health and should contribute to the establishment of a risk management policy. Specific factors identified for harmonisation include the animal species, food commodities, sampling plans, bacterial species, antimicrobials to be tested, laboratory methods, data reporting, database structure and the structure of reports.

Thirty-seven of 53 diarrhoeic calves hospitalised for intravenous fluid therapy were classified as very severely acidotic (total carbon dioxide less than 8 mmol/litre) by using a Harleco apparatus. All the calves were given intravenously 10 to 20 litres of electrolyte solution which contained 144 mmol/litre sodium, 4 mmol/litre potassium, 113 mmol/litre chloride and 35 mmol/litre bicarbonate, and in addition the 37 very severely acidotic calves received 400 ml of 1M sodium bicarbonate in the first 5 litres of fluid administered. Sixteen of the 37 very severely acidotic calves had a distended right flank, suggesting the presence of a dilated fluid-filled viscus. Neither their history nor other clinical signs were useful predictors of the distension. The distended calves had significantly higher plasma concentrations of sodium and chloride, and significantly lower plasma creatinine concentrations than the calves which were not distended. Treatment was successful in all the 21 non-distended calves but four of the distended calves died despite treatment. The resolution of the distension in the successfully treated calves, coincided with a significant increase in plasma bicarbonate concentration and the passage of large amounts of malodorous mucoid faeces.

Thirty-eight, one- to two-week-old calves with experimentally induced Escherichia coli diarrhoea were randomly assigned to three treatment groups. Two groups of 15 calves were treated intramuscularly once daily for three days with either danofloxacin mesylate at 1.25 mg/kg bodyweight, or with baquiloprim/sulphadimidine as a positive control (10 mg of combined active ingredient/kg); eight calves were treated with 0.9 per cent sodium chloride solution as a negative control (1 ml/20 kg). Faecal consistency, demeanour, hydration status, appetite and bodyweight were monitored before, during, and for four days after treatment by an investigator unaware of the animals9 treatment. Before treatment, the clinical, biochemical, and faecal indices were similar among the groups. By 24 hours after treatment began, the proportion of observations of faeces recorded as of normal consistency was highest in the danofloxacin-treated group (26 of 60), compared with 16 of 60 in the baquiloprim/sulphadimidine treated groups and four of 32 in the control group. The proportion of calves with a normal demeanour was highest in the danofloxacintreated group at all the evaluations and these calves gained significantly (P

The number of potential annual generations of the rusty grain beetle,Cryptolestes ferrugineus, was simulated in wheat stored in granaries for all crop districts in the prairie provinces of Canada each year from 1952 to 1990 using a population dynamic model driven by ecological variables. Granary size was assumed to be 6 m in diameter. Historical data for temperatures at harvest and times when storage began were used in the simulation model. A second model, which predicted the rate of temperature change at the centre of a 6-m-diameter bulk of wheat, determined environmental parameters for the population dynamic model. (Grain moisture content was assumed constant at 14.5% wet mass basis.) The combined model shows that the initial storage temperature is the most important factor responsible for predicting the number of generations and levels of infestation ofC. ferrugineus. This finding was largely validated by historical grain storage and infestation data. For various years initial grain temperature ranged from 17.7 to 37.4 °C and harvest dates were between 1 August and 20 October. The number of generations annually in simulations based on field conditions ranged from 0.35 to 6.77 with a mean of 3.29. Three or more generations result in a severe infestation and every year at least three simulated generations were completed in some crop districts. In one year, at least three generations were completed in every crop district. Harvest temperature and date permit prediction of crop districts that will potentially have the largest populations of C.ferrugineus so that early monitoring of wheat for infestations can be targeted to areas most at risk.

Corn grain (23.6% moisture) was treated immediately after harvest with DMX-7 Mold Inhibitor (48% propionic acid) at rates of 0, 0.05, 0.1, and 0.2% DMX-7. After treatment, the grain was augered into modified grain bins and dried using ambient air. The incidence of storage fungi was determined following plating of kernels on malt salt agar. DMX-7 Mold Inhibitor reduced the incidence of Penicillium spp. and at some grain sampling levels Aspergillus spp. when compared to the untreated. In general, the control of storage fungi resulted in fewer damaged kernels as determined by a licensed federal grain inspector, however, the difference was only significant on some sampling dates.

We examined 27 hepatectomy specimens to assess the frequency of foam cell endovasculitis and bile duct loss in chronic rejection. Arterial lesions, defined as total occlusion by subintimal foam cells and/or fibromuscular proliferation, were found mainly in hilar and septal arteries, whereas bile duct loss, defined as the absence of bile ducts in more than 50% of portal tracts, affected mainly small tracts. Both were found in 20 livers (74%). In two livers (7%) there was significant bile duct loss but no arterial lesions, whilst in five cases (19%) there were occlusive arterial lesions but no bile duct loss. Small arteries were involved in only 10% of the cases. These results indicate that in one-third of the cases arterial and bile duct lesions develop independently of each other, suggesting different pathogenetic pathways. In addition, liver biopsy may not be pathognomonic since small arteries are involved in only 10% of cases and bile duct loss may not be extensive. In such cases the diagnosis of chronic rejection should only be made in the presence of progressive clinical deterioration.

This investigation involved the use of a fungicide, iprodione (trade name ROVRAL® 4F, Rhone-Poulenc Ag Company), to retard mold growth in shelled corn while it was being dried with unheated ambient air at lower-than-normal airflow rates. The lowest airflow of about half of normal recommended airflow resulted in savings for drying of 50% and electrical demand reduction of 75%, compared with drying with normal airflow. In conducting this research, corn of approximately 24% moisture was loaded into five different drying bins. Each of the bins was divided vertically down the center, with one half of the corn being treated with a fungicide and the other half left untreated. Mold damage levels in the treated corn were appreciably lower than in the untreated corn in all the bins, averaging 7.2% mold damage for treated corn and 10.9% for untreated corn. The drying cost (including energy, fungicide, and estimated typical damage discounts) was lower for treated corn in two of the five bins.

1. The role played by the endothelium-derived relaxing factor (EDRF), nitric oxide (NO) in the regulation of blood flow to the skeletal muscle vasculature of the dog skinned hindlimb has been determined by examining the effects of the NO synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME) upon (i) basal iliac artery blood flow, (ii) vasodilator responses to endothelium-dependent and -independent agonists and (iii) reactive hyperaemic responses to arterial occlusion. 2. L-NAME (0.1-3 mg min-1) infused directly into the iliac artery dose-dependently reduced basal iliac artery blood flow by a maximum of 48.6 +/- 6.9% (n = 4) and also increased mean systemic arterial blood pressure by 25.6 +/- 5.0 mmHg (n = 4) (at 3 mg min-1 L-NAME). 3. Over the same dose range, L-NAME also inhibited the peak vasodilator responses to intra-arterially administered, submaximal bolus doses of the endothelium-dependent agonists, bradykinin (3-300 ng) and acetylcholine (30-300 ng) by approximately 40%. In contrast, peak vasodilator responses to the endothelium-independent agonists, sodium azide (3-30 micrograms) and adenosine (0.3-1 mg), and peak reactive hyperaemic responses to arterial occlusion (60 s) were largely unaffected by L-NAME. 4. The dose-related effects of L-NAME on basal iliac artery blood flow, mean systemic arterial blood pressure and endothelium-dependent vasodilator responses were significantly attenuated by pretreatment with L-arginine (100 mg min-1) followed by co-infusion of L-arginine (100 mg min-1) with L-NAME. 5. In conclusion, these data suggest that NO plays some role in regulating basal blood flow and in mediating the vasodilator responses to the endothelium-dependent agonists bradykinin and acetylcholine in the skeletal muscle vasculature of the dog hindlimb. The substantial component (~60%) of the peak vasodilator responses to bradykinin and acetylcholine, unaffected by L-NAME, may be independent of NO, or be mediated by an alternative EDRF-dependent but L-NAME-insensitive mechanism.

Minimum inhibitory concentrations of 13 beta-lactam antibiotics (ampicillin, amoxycillin, amoxycillin/clavulanate, imipenem, cefazolin, cefadroxil, cefaclor, cefuroxime, cefotaxime, cefepime, cefpirome, cefpodoxime and cefixime), were determined for 76 strains of beta-lactamase negative Haemophilus influenzae, isolated over a five year period (1985-1990) that gave reduced zones to cefuroxime on disc testing when compared to the control strain H. influenzae NCTC 11931. MIC90 values for all antibiotics (except imipenem) were approximately ten times higher than the MIC90 values for a susceptible control group. Increased resistance was not associated with any particular biotype, although three biotype III strains were highly resistant to imipenem. More than 50% of strains with reduced susceptibility to beta-lactam antibiotics were isolated from patients with chronic respiratory disease. Published data on the sputum concentration of each antibiotic were compared to the MIC90 values obtained for the susceptible and resistant strains.

Three-hundred and twelve episodes of fever in 234 neutropenic patients with haematological malignancies were treated empirically with either imipenem or a combination of piperacillin and gentamicin. There were no significant differences in the percentages of patients responding to therapy at either 72 h (59% and 56% of assessable episodes in the imipenem and combination groups respectively) or at the end of treatment (55% and 53% of assessable episodes in the imipenem and combination groups respectively). Patients in the piperacillin plus gentamicin group experienced significantly more renal tubular damage whereas those who received imipenem suffered more nausea or vomiting. We conclude that imipenem monotherapy represents an acceptable alternative to piperacillin plus gentamicin as empirical therapy of the febrile neutropenic patient.

An adult Chinese red panda ( Ailurus fulgens styani) transported by airplane from Florida to a North Dakota zoo died 1 week after arrival. Grossly, an interscapular abscess, subcutaneous inflammation, lymphadenitis, and pulmonary abscesses were observed. Microscopic findings included necrotizing inflammation in liver, lung, lymph node, and spleen. Chromobacterium violaceum was cultured from the interscapular abscess, liver, lung, and spleen and was injected into Swiss Webster mice. These mice died 18 hours postinoculation, and C. violaceum was cultured from liver, lung, and spleen. Chromobacterium violaceum is a sporadically reported but highly virulent pathogenic bacterium of both animals and humans typically found as a soil and water inhabitant of tropical and subtropical regions.

Restriction endonuclease digestion of Acanthamoeba whole-cell DNA was used to study the relationship between 33 morphologically identical strains from keratitis cases (30 strains), contact lens storage containers (2 strains), and soil (1 strain). Samples digested with BglII, EcoRI, or HindIII and separated by agarose gel electrophoresis contained detectable mitochondrial DNA restriction fragment length polymorphisms (RFLPs). By comparing RFLPs, the strains could be assigned to seven multiple-strain and three single-strain groups. The largest of these contained nine strains, eight of which were isolated in keratitis cases in various locations worldwide and may indicate a group particularly associated with keratitis. Restriction endonuclease analysis of whole-cell DNA is proposed as a valuable technique for detecting mitochondrial DNA RFLPs in the differentiation of morphologically identical Acanthamoeba strains and may therefore be useful in resolving the complex taxonomy of the genus, which has hitherto been founded on subjective morphological criteria.

Genetic diversity among 22 Escherichia coli strains isolated from chickens with swollen-head syndrome (SHS), an acute respiratory disease of domestic poultry, and 93 strains isolated from birds with colibacillosis was assessed on the basis of allelic variation at 20 enzyme-encoding loci detected by multilocus enzyme electrophoresis. SHS isolates from Spain and Canada were polymorphic at 14 loci and were classified into 19 multilocus genotypes, defining clones that differed on average at 34% of the loci. In most cases, SHS isolates of different clonal genotypes were distinct in O:H serotype and expressed different fimbrial antigens. Comparisons with 93 isolates obtained from birds with colibacillosis revealed enzyme polymorphisms at 17 of 20 loci, with an average of 3.5 alleles per locus. In the total sample, 56 clonal genotypes were distinguished, with 27 (23%) of the isolates belonging to one of three common clones. Both SHS and colibacillosis isolates were genetically diverse, with an average single-locus diversity of 0.36, indicating that a wide variety of naturally occurring bacterial clones is associated with these acute avian infections. Six previously defined groups of clones identified in diseased birds from the United States were represented in isolates from Spain, indicating that similar clones occur in widely separated geographic areas. In addition, one group of SHS isolates was closely related to a recognized widespread clone complex incriminated in human septicemia and meningitis. The results suggest that certain strains implicated in SHS infections belong to a clone complex whose members have special attributes that promote involvement in invasive diseases in humans and animals.

An assessment of risk-taking behaviour among men who have sex with men (MSM) attending a sauna venue was undertaken, using a standardized questionnaire, after which outreach screening was introduced targeting MSM. The epidemiology of the continuing outbreak of syphilis was reviewed to determine the factors driving the outbreak and assess the benefit of continuing outreach screening. Findings among the 163 respondents at the sauna included a high rate of casual sex and a tendency not to disclose HIV status. Over 12 months, 51 cases of early syphilis were recorded. Our review showed a decline in incidence in MSM after outreach screening, but an increase in heterosexual spread. Given the frequent anonymous nature of syphilis transmission, traditional contact tracing is ineffective. Outreach screening is required at gay venues and other community settings to target at-risk populations.

The history and results of a clinical examination were recorded for 32 spring-born suckler calves which were hospitalised for intravenous fluid therapy. Blood samples were taken before treatment, during treatment and before discharge and analysed for colostral status, total carbon dioxide as an indication of acid-base status, and haematocrit. All the calves were given intravenously 5 to 10 litres of electrolyte solution containing 144 mmol/litre sodium, 4 mmol/litre potassium, 113 mmol/litre chloride and 35 mmol/litre bicarbonate, supplemented, in 24 calves, with up to 450 ml of 1M sodium bicarbonate. Nearly all the calves were recumbent but less than half were dehydrated on admission. The signs of dehydration were well correlated with each other and with the haematocrit. Neither the history nor the clinical signs were useful predictors of acidosis. There was no relationship between the severity of acidosis and the degree of dehydration. Acidosis was more prevalent in older calves (P < 0.01). For the severely acidotic calves, supplementary intravenous fluid with sodium bicarbonate significantly (P < 0.05) improved the total blood carbon dioxide at discharge. All 32 calves recovered. It is possible to treat acidotic calves with intravenous fluid therapy effectively, economically and according to their individual needs. The Harleco apparatus is a simple, useful, cost-effective adjunct to the diagnosis and treatment of this life-threatening condition.

The Ad hoc Group of experts on antimicrobial resistance, appointed by the Office International des Epizooties, has developed an objective, transparent and defensible risk analysis process, providing a valid basis for risk management decisions in respect to antimicrobial resistance. The components of risk analysis and of different possible approaches in risk assessment (qualitative, semiquantitative and quantitative) are defined. The Ad hoc Group recommended the following: an independent risk assessment based on scientific data; an iterative risk analysis process; a qualitative risk assessment systematically undertaken before considering a quantitative approach; the establishment of a risk assessment policy; and the availability of technical assistance for developing countries.

This guideline, developed by the Office International des Epizooties for the monitoring of the quantities of antimicrobials used in animal husbandry, provides the methodology required to assess the amounts of antimicrobials used, to supply data to be used for risk analysis and to improve guidance on the appropriate use of antimicrobials. Information may be gathered from a number of sources, such as the competent authorities, industry and users. The usefulness of different types of information is discussed and recommendations are given on how to collect detailed information, each year, on the antimicrobial quantities used per class and active substance. Information should also be collected on the route of administration (oral and parenteral) and the animal species.

1. We have investigated the receptors mediating endothelin-induced contraction of rabbit isolated jugular vein (RJV) and rat isolated thoracic aorta (RTA). 2. Endothelin-1 (ET-1) and endothelin-3 (ET-3) contracted RJV preparations with similar potency (EC50 values approximately 1 nM), whereas, ET-1 (EC50:4.5 nM) was approximately 80 fold more potent than ET-3 in contracting RTA. In addition, the ETB receptor-selective agonist [Ala1,3,11,15]ET-1 contracted RJV (EC50:2.1 nM) but not RTA. 3. The ETA receptor antagonist, BQ123, competitively antagonized (pA2 6.93) the contraction of RTA produced by ET-1, but had no effect (at 10 microM) on the contractile effects of either ET-1, ET-3 or [Ala1,3,11,15]ET-1 in RJV. 4. These data suggest that both ETA and ETB receptors can mediate vascular smooth muscle contraction.

This study reports the presence of two fractions from corn seeds inhibitory to aflatoxin formation. Using a sensitive laboratory assay that can measure both inhibition of fungal growth and inhibition of aflatoxin biosynthesis, we examined aqueous extracts from seeds of Tex6, a corn inbred shown to be highly resistant to aflatoxin accumulation in field and laboratory evaluations. In these extracts, we identified two biologically active fractions. One inhibited growth of Aspergillus flavus and, thus, aflatoxin accumulation, and the other inhibited aflatoxin formation with little effect on fungal growth. The compounds responsible for these activities appear to be proteaceous, as they are water soluble, heat labile, and sensitive to proteinase K treatment. The compounds were partially purified by ultrafiltration and chromatography. The estimated molecular mass of the growth inhibitor is approximately 28 kDa, and that of the aflatoxin biosynthesis inhibitor appears to be greater than 100 kDa. Partially purified preparations of the growth inhibitor and aflatoxin biosynthesis inhibitor cause 50% inhibition at 26 and 75 μg of protein/ml, respectively. The presence of these compounds in Tex6 may explain its resistance to aflatoxin accumulation.

Kernels of a maize inbred that demonstrated resistance to aflatoxin production in previous studies were inoculated with an Aspergillus flavus strain containing the Escherichia coli beta-D-glucuronidase reporter gene linked to a beta-tubulin gene promoter and assessed for both fungal growth and aflatoxin accumulation. Prior to inoculation, kernels were pin-wounded through the pericarp to the endosperm, pin-wounded in the embryo region, or left unwounded. After 7 days incubation with the fungus, beta-glucuronidase activity (fungal growth) in the kernels was quantified using a fluorogenic assay and aflatoxin B content of the same kernels was analyzed. Kernels of a susceptible inbred, similarly treated, served as controls. Results indicate a positive relationship between aflatoxin levels and the amount of fungal growth. However, resistant kernels wounded through the pericarp to the endosperm before inoculation supported an increase in aflatoxin B over levels observed in nonwounded kernels, without an increase in fungal growth. Wounding kernels of the resistant inbred through the embryo resulted in both the greatest fungal growth and the highest levels of aflatoxin B1 for this genotype. Maintenance of resistance to aflatoxin B1 in endosperm-wounded kernels may be due to the action of a mechanism which limits fungal access to the kernel embryo.

Thirty-nine Escherichia coli isolates from broiler chickens with cellulitis were serotyped and analyzed for clonal relationships by multilocus enzyme electrophoresis. The isolates were further characterized with respect to hemagglutination (HA); serum resistance; antibiotic susceptibility; production of aerobactin, colicin V, and hemolysin; expression of K1 or K5 capsule; sensitivity to cloacin DF13 after treatment with diphenylamine; expression of iron-regulated outer membrane proteins; and virulence in 1-day-old chickens. In addition, the isolates were examined for the presence of DNA sequences related to F1A (fim) and P (pap) fimbriae, aerobactin synthesis (iuc) and transport (iut), hemolysin operon hly, and TraT lipoprotein-induced serum resistance (traT). Only 38.4% of the isolates were typeable with standard O antisera, and of these, serogroups O25 and O78 were the most frequently observed. Multilocus enzyme electrophoresis, based on 20 enzymes, resolved 17 electrophoretic types, forming seven clusters. Isolates from four of these clusters fell into E. coli clone complexes that have been previously reported to be commonly associated with avian colibacillosis. All isolates expressed two to five iron-regulated outer membrane proteins, were resistant to serum and cloacin DF13, and possessed DNA sequences homologous to fim and iuc/iut. Most isolates (72%) were positive for traT, and a majority produced colicin V and aerobactin (92 and 82%, respectively). Assays for the presence of fim and pap DNA sequences, for HA, and for virulence gave variable results but suggest that cellulitis isolates may express F1A and/or other mannose-resistant HA fimbriae different from P and may be virulent in 1-day-old chickens. Our results support the hypothesis that cellulitis in broilers in many cases is caused by E. coli clones identical to other pathogenic avian E. coli strains. Certain clones may be specific to cellulitis, because 25% of the isolates tested belong to clusters not related to known clone complexes.

Seventy-two laboratory confirmed cases of Campylobacter infection were identified in people who attended a large festival in England. A case-control study was undertaken to identify the vehicle of infection. Potential risk factors included the water supply to the site, and food, bottled spring water and unpasteurised milk sold at the event. Only the consumption of unpasteurised milk showed a statistical association with having a Campylobacter infection, strongly suggesting that this was the vehicle of infection.

1. A number of putative endothelin (ET) receptor ligands were synthesized with a view to assessing their relative affinity for human recombinant ET receptors. 2. Human (h) and endothelin ETA and ETB receptor open reading frames were cloned by reverse transcription-polymerase chain reaction into the mammalian expression vector pcDNA1 and stable cell lines were created by transfection of Chinese hamster ovary cells. 3. Scatchard analyses of saturation isotherms for the specific binding of [125I]-endothelin-1 ([125I]-ET-1) to membranes, prepared from Chinese hamster ovary cells transfected with hETA or hETB receptors, yielded values for equilibrium dissociation constants (Kd) of 20.5 +/- 1.8 pM and 25.5 +/- 5.5 pM, respectively. Hill coefficients did not differ significantly from unity, suggesting binding to homogeneous, non-interacting receptor populations. 4. Pharmacological characterization of the transfected hETA and hETB receptors was undertaken by measuring the relative abilities of ETA and ETB receptor-selective peptide ligands to inhibit binding of [125I]ET-1. For interaction with hETA receptors, the relative order of potency was ET-1 > ET-3 = FR139317 = BQ123 >[Ala1,3,11,15]-ET-1 = sarafotoxin S6c (S6c). In contrast, the relative order of potency, at hETB receptors, was ET-1 = ET-3 = [Ala1,3,11,15]-ET-1 = S6c >> FR139317 = BQ123. 5. The novel non-peptide ligands, Ro 46-2005, SB 209670 and BMS 182874, were found to inhibit [125I]-ET-1 binding to human recombinant ETA and ETB receptors. At hETA receptors, the calculated pIC50 values were 6.7 (Ro 46-2005), 8.7 (SB 209670) and 5.8 (BMS 182874), while at hETB receptors, the corresponding pIC50 values were 6.8, 7.5 and

Endothelin (ET) ETA receptors on vascular smooth muscle are believed to mediate the vasoconstrictor effects of ET isopeptides, and ETB receptors on the endothelium are thought to mediate the vasodilator effects. This study has investigated the receptors mediating endothelin-induced contraction of isolated ring preparations of rat thoracic aorta (RTA) and rabbit carotid artery (RCA), pulmonary artery (RPA), and jugular vein (RJV). In RTA and RCA, ET-1 (EC50 4.5 and 5.2 nM, respectively) was 82- and 108-fold, respectively, more potent than ET-3, whereas the ETB receptor-selective agonists sarafotoxin S6c (S6c) and Ala1,3,11,15-ET-1 (4-Ala-ET-1) were without effect up toor = 1 microM. In contrast, in RPA and RJV, ET-1 (EC50 3.1 and 0.7 nM, respectively) and ET-3 (EC50 4.4 and 0.9 nM, respectively) were equipotent, and 4-Ala-ET-1 (EC50 10.7 and 2.1, respectively) and S6c (EC50 0.4 and 0.1 nM, respectively) were potent contractile agonists. The ETA receptor antagonist BQ123 (D-Val-Leu-D-Trp-D-Asp-Pro) competitively antagonized the effects of ET-1 in RTA and RCA (pA2 values 6.9 +/- 0.1 and 6.8 +/- 0.2, respectively) but did not antagonize (at 10 microM) contractions to ET-1, ET-3, or 4-Ala-ET-1 in RPA and RJV. In conclusion, contraction of vascular smooth muscle by endothelins can be mediated by both ETA and ETB receptors.

Laboratories that reported isolations of Streptococcus sanguis from blood cultures to the Communicable Disease Surveillance Centre (CDSC) Colindale were requested to submit strains to Bath Public Health Laboratory to allow the prevalence of penicillin tolerance within different biotypes of this species to be studied. One hundred and fifty one Streptococcus spp were received from 78 United Kingdom laboratories in one year. Strains were identified using the API 20 Strep, and minimum inhibitory concentrations (MICs) of penicillin were determined using the spiral gradient plate method. Penicillin tolerance was detected by spraying beta-lactamase over inoculated gradient plates, reincubating for 48 hours and counting the number of surviving organisms represented by colonies. There were 57 different API identification profiles encountered in the survey. Most S sanguis I/1 strains were penicillin tolerant, most S sanguis II strains were non-tolerant. The overall geometric mean MIC of penicillin was considerably lower for S sanguis I/1 than for all other biotypes. The distribution of biotypes and the geometric mean MIC of penicillin for each biotype were not significantly different for infective endocarditis strains than for all strains tested, suggesting little or no association between penicillin tolerance and the seeding of endocardium. When the reactions obtained using API 20 Strep were compared with a recent taxonomic study of viridans streptococci, 22 of 38 S sanguis I/1 strains could be reclassified as S gordonii; all these strains were penicillin tolerant. Such reclassification would allow likely penicillin tolerant strains to be predicted.

Three experiments compared the efficacy of the fungicides thiabendazole or iprodione with a water carrier before or after drying, and with an oil carrier at dust-control rate before drying for control of storage fungi. A fourth experiment compared the efficacy of thiabendazole applied in water, degummed soybean oil, food-grade soybean oil, or white mineral oil carrier before grain drying, and measured the efficacy of each oil without fungicide. After high-temperature drying, grain was stored for 40-42 wk in modified grain bins. The incidence of storage fungi was determined following plating of kernels on malt salt agar. All fungicide treatments reduced the incidence of Penicillium and Aspergillus spp. when compared to non-fungicide-treated controls

Corn grain was treated immediately after harvest with the fungicides benomyl (0, 1, 5, and 10 μg/g), thiabendazole (0, 5, 10, and 20 μg/g), and A9248 (0, 5, 10, and 20 μg/g) in 1984, and with thiabendazole (0, 10, and 20 μg/g) and A9248 (0, 5, 10, and 20 μg/g) in 1985 to determine the effect of the fungicides on infection by storage fungi during ambient air drying and storage. After treatment, the grain was augured into modified grain bins and dried with ambient air. The incidence of storage fungi was determined following plating of kernels on malt salt agar. Fungicide treatments reduced the incidence of Penicillium species, and in some cases Aspergillus species, when compared to the nontreated control (.)

Four hundred twenty turkey and 80 chicken Escherichia coli isolates from colisepticemic birds were examined for the following properties: heat-labile toxin (LT), heat-stable enterotoxin, verotoxin, colicinogenicity, hemolysin, and hydroxamate/aerobactin production. Twenty-four (5.7%) of the 420 turkey isolates and six (7.5%) of the 80 chicken isolates produced an LT that was cytotoxic for both Vero and Y-1 cells. In contrast, 48 (11.4%) of the turkey isolates and 18 (22.5%) of the chicken isolates produced a distinct LT that was cytotoxic only for Vero cells. In addition, 64 (80.0%) of the chicken isolates and 309 (74.0%) of the turkey isolates produced aerobactin. Colicinogenicity occurred in 51 (64.0%) of the chicken isolates, with 41 (51.0%) producing colicin V. By contrast, 254 (61.0%) of the turkey isolates produced a colicin, of which 176 (42.0%) produced colicin V. None of the chicken and turkey isolates produced hemolysin or heat-stable enterotoxin.

Tribolium castaneum infestation of stored wheat led to significant increases in fat acidity (FAV) and decreases in germination and microfloral levels. The FAV increased with time regardless of insect activity, although the resulting alteration of the composition of both the microflora and cereal substrate led to a more rapid FAV increase. The total microbial spore count sharply increased after 8 wk of storage. The insects appeared to inhibit fungal growth and decreased the spore count. The level of wheat infection by Aspergillus spp. ( A. glaucus group, A. fiavus ) and Penicillium spp. decreased between 8 and 12 wk storage, possibly because of bacterial growth. Seed germination decreased steadily during 18 wk. Because of the destruction of the germ by insect feeding, insect-infested wheat underwent rapid germination loss.

The effects of various seed moisture contents in hulless (cv. Terra) and hulled oats (cv. Random) on susceptibility to mite infestation and on mycofloral growth and germination loss were studied at weekly intervals. Fat acidity values were determined for Terra oats only after 4 wk of storage. Moisture content-relative humidity adsorption and desorption curves were determined for Terra at 22 °C and at relative humidities of 35–100%. Terra oats, which had a higher level of Penicillium infection at 90–100% RH than Random oats, lost viability more rapidly than Random. Fat acidity values of Terra increased rapidly from 35 mg KOH/100 g of seed to 87–118 mg KOH/100 g of seed, only when seeds were stored at 90–100% RH. Terra offered a more favorable substrate for the multiplication of the mites Tyrophagus putrescentiae, Acarus farris, and Lepidoglyphus destructor than did Random. With the exception of susceptibility to mite infestation, safe storage criteria are similar for hulled and hulless oats at usual moisture contents.

Moisture content-relative humidity (MC-RH) adsorption and desorption curves were determined for triticale (× - Triticosecale Wittmack), cv. Welsh, at 22 °C and 35–100% RH. The effects of various seed moisture contents on free fatty acid level, microfloral growth and germination loss were determined after 5 wk of storage at various RH and 22 °C. Infection of seeds by Penicillium and Aspergillus glaucus group occurred above 80–85% RH and seed germination correspondingly began to decrease. Five common stored-product mites which infested triticale stored at 20 °C and 85% RH were: Acarus siro, A. farris, Aëroglyphus robustus, Lepidoglyphus destructor and Tyrophagus putrescentiae. A. farris and L. destructor also multiplied on wheat cv. Neepawa which was an inferior substrate to triticale for A. farris.

Three pyrethroid insecticides, cypermethrin, fenvalerate, and permethrin, were applied at 0.2, 0.5, and 1.0 g of Al/m2 to plywood panels, 12 by 12 by 0.6 cm. The panels were stored for 33 weeks at 10, 20, and 30°C and were bioassayed at these temperatures with groups of 20 adult Tribolium castaneum (Herbst) at 1, 3, 6, 13, and 33 weeks after insecticide applications. All insecticides produced high knockdown of T. castaneum at 33 weeks, with the exception of fenvalerate at 0.2 g of AI/m2, which resulted in only 26, 9.5, and 85% knockdown at 10, 20, and 30°C, respectively. None of the insecticides produced 100% mortality even at 1.0 g of Al/m2 after exposure at 1 week. Cypermethrin and fenvalerate often resulted in significantly higher mortalities at 20°C than at 10 or 30°C, whereas permethrin generally resulted in mortalities which increased with temperature. The use of these insecticides in empty granaries is unlikely, because of high cost and the high concentrations required for effective insect control.

Wheat treated with 2,4, or 8 ppm of insecticide, on a whole-seed basis, was bioassayed with Tribolium castaneum (Herbst) and Cryptolestes ferrugineus (Stephens) adults at 30 °C and 70% RH after 4 days, 2 weeks, and then at eleven 1-month intervals. Malathion was more toxic to C. ferrugineus than to T. castaneum whereas the reverse was true for pirimiphos-methyl; malathion showed little effectiveness after 2 weeks. The pyrethroids, cypermethrin and permethrin, were more toxic to T. castaneum than to C. ferrugineus. For malathion and pirimiphos-methyl, percentage knockdown of the insects following exposure for 24 h was similar to percentage mortality after a 3-day recovery period; for cypermethrin and permethrin under the same conditions, knockdown was consistently greater than mortality. Cypermethrin at 8 ppm on wheat gave 90% knockdown of T. castaneum after 1 year of storage. Pirimiphos-methyl gave nearly 100% control of both species for 9 months at 4 ppm and 11 months at 8 ppm, and of the grain mite Acarus siro (L.) for at least 4 weeks at 8 ppm. Seed germination did not change during 1 year of storage; the levels of Penicillium spp. infection observed were much greater (about 60%) on wheat treated with pirimiphos-methyl (2, 4, 8 ppm) or cypermethrin (2 ppm) than with malathion or permethrin.

Principal component analysis (PCA) was used to determine the effects of infestation of bulk stored wheat by multiple species of insects at 30±2°C for 60 wk. Eight 204-liter drums containing wheat at 15.5% moisture content were used as three distinct man-made ecosystems: (a) Control system (2 drums), insect-free; (b) RST system (3 drums), artificially infested withRhyzopertha dominica (F.),Sitophilus oryzae (L.), andTribolium castaneum (Herbst); and (c) COT system (3 drums), infested withCryptolestes ferrugineus (Stephens),Oryzaephilus surinamensis (L.), andTribolium castaneum. The variables measured tri-weekly within each system included carbon dioxide, oxygen, temperature, grain moisture, seed damage, grain weight and volume, dust weight and volume, fat acidity values (FAV) of the wheat, seed germination, microflora includingAlternaria alternata(Fr.) Keissler,Aspergillus glaucus group,Aspergillus candidusLink, and bacteria, insects and the miteTarsonemus granariusLindquist. PCA provided multivariate synopsis of the data quantifying several important relationships among the variables monitored. Tri-weekly and cumulative 60-wk analyses of each system showed that high bacterial counts were associated with high FAV levels;Tarsonemus numbers were positively related toAspergillus; Alternaria and seed germination were negatively related to FAV, bacteria and grain damage; and that the number of insects was related to the presence ofAspergillus and negatively related to the presence of bacteria. Seed germination andAlternaria infection often decrease rapidly presumably because of infection by fungi of theAspergillus glaucus group. The combined action ofR. dominica andAspergillus spp. enhanced seed damage and increased grain moisture content thus promoting bacterial growth which in turn inhibited insect and mold growth. Fat acidity values increased with time unless seed damage and bacterial infection were extensive as in the RST system.

The consequences of infestation of bulk-stored wheat by multiple species of insects were determined for 60 weeks at 30 ± 2 °C. Eight 204-L drums containing wheat at 15.5% moisture content were used as three distinct systems: (I) Control system (two drums), insect free; (II) RST system (three drums), infested with the grouping of Rhyzopertha dominica F., Sitophilus oryzae (L.), and Tribolium castaneum (Herbst); and (III) COT system (three drums), infested with the grouping of Cryptolestes ferrugineus (Stephens), Oryzaephilus surinamensis (L.), and T. castaneum. At triweekly intervals carbon dioxide, oxygen, temperature, grain moisture, seed damage, grain weight, dust weight, fat acidity values (FAV), seed germination, microflora, and the numbers of insects and the mite Tarsonemus granarius Lindquist were measured. Seeds died by week 15 and bacterial infection on them increased in all systems. The seed FAVs in the RST system peaked by week 30 and then declined steadily while these values were increasing continuously in the Control and levelling off in the COT systems. Insects multiplied exponentially for 6–15 weeks and then declined sharply or maintained oscillating populations; Sitophilus and Oryzaephilus were unable to survive in the presence of the other insects.

Glass bottles containing 100 g of wheat which was insecticide free or was treated with malathion (formulated as a dust) at 1, 2, or 8 ppm were infested with 20 eggs of Plodia interpunctella or Ephestia cautella . After 2 weeks of storage at 27°C, an additional 20 moth eggs were introduced into the bottles of wheat treated with malathion at 2 and 8 ppm, since the original young larvae were killed. Insect numbers and grain quality were determined at 2, 4, 6, and 8 weeks in storage. Both P. interpunctella and E. cautella developed and multiplied in the insecticide-free wheat. The initial dose of malathion at 1 ppm effectively controlled P. interpunctella; no larvae developed into adults. A few E. cautella survived, and a mean of 1 adult per bottle was observed at 8 weeks of storage. Since Insecticide degradation had occurred, both species of moths developed successfully when wheat which initially contained malathion at 2 ppm was reinfested after 2 weeks of storage. However, larval mortality of both species was high. For both species, none of the original larvae or those developing from eggs added after 2 weeks survived with malathion at 8 ppm. A I-ppm dose of malathion dust controlled P. interpunctella larvae, but levels above 2 ppm were needed to control E. cautella . The moisture content of the grain, which fluctuated between 15 and 18%, was not affected by the insect populations. Seed damage caused by insect feeding, seed germination, and seed-borne microtlora was largely related to insect numbers in the various treatments.

Mothers' feeding practices and their attitudes to breast and bottle feeding were investigated. Sixty-four per cent started to breast feed and 35% continued past 2 months, a continuation rate which is higher than previously reported. Also higher than previously reported was the proportion of working class women breast feeding. This may reflect a current trend. Most women decided on their infant feeding technique early in pregnancy, and 80% followed that decision. For those who changed their minds about feeding practice postnatally, and for those who were initially undecided, the hospital was influential. Analysis of women's pleasurable and less restricting than they had anticipated. The results are discussed in relation to attempts to encourage breast feeding.

Stored wheat that was infested by each of 3 species of mites, Lepidoglyphus destructor (Schrank), Acarus farris (Oudemans), and Aeroglyphus robustus Banks, was studied to determine the effects of mites on the quality of wheat. L. destructor infestation of the grain led to significantly lower fat acidity values ( P

The effects of the beta 2-agonist salbutamol, on pig heart rate and blood pressure were evaluated at the expected commercially used concentration of 3 ppm in final feed, and at three times this level. Salbutamol was administered to pigs previously fed on control diet ('naive'), and in a second study to pigs fed 3 ppm salbutamol for 19 days ('acclimatized'). Heart rate and blood pressure were measured in conscious 30 kg pigs before (pre-ingestive), during (ingestive) and after ingestion (absorptive) of feed containing 3 or 9 ppm salbutamol. To assess any interaction with 'stress genotype' pigs, measurements were performed in Large White and Pietrain-cross breeds. The mean preingestive heart rates for the Large White and Pietrain-cross pigs were 127 and 109 beats/min, respectively. The corresponding figures for mean arterial blood pressure were 121 and 122 mmHg. The act of ingesting control feed caused heart rate to rise by 36-39% and blood pressure to increase by 17-27%. During the absorptive phase for 'naive' pigs fed 3 ppm salbutamol in the diet, blood pressure fell 5-11% and heart rate increased 20-24%, reflecting a classical baroreceptor mediated response. At 9 ppm the fall in blood pressure of 5-11% was similar to that at 3 ppm, while the rise in heart rate was larger at 31-38%. The magnitude of the changes at both 3 and 9 ppm was less than that evoked by the act of ingestion, with the exception of the heart rate response in Large Whites at 9 ppm, which was similar. The responses of the two breeds were comparable, indicating that salbutamol is unlikely to exacerbate the cardiovascular responses seen in potentially stress-susceptible pigs. The acute changes elicited by 3 ppm salbutamol during the absorptive phase in 'naive' pigs were abolished or substantially less in acclimatized pigs, implying a tachyphylaxis to the agonist's actions. This was confirmed by 9 ppm of salbutamol increasing heart rate of 'acclimatized' Large Whites to the same degree as 3 ppm in 'naive' counterparts. The desensitization in Pietrain-cross pigs was even more marked with no increase in heart rate produced by 9 ppm salbutamol following acclimatization. These data, combined with the rapid tachyphylaxis of response, indicate that salbutamol at the intended commercial inclusion of 3 ppm will not compromise the cardiovascular stability of the growing pig at rest.

This research aimed to evaluate an intervention to increase sexual health awareness and encourage testing for STIs within a community setting (a sauna), in an attempt to reduce sexual risk behaviours within MSM (men who have sex with men). Men were provided with sexual health information and offered sexual health testing monthly in the sauna. Questionnaires were administered over three time points to measure sexual risk behaviours and use of sexual health services. 539 questionnaires were completed; there was a high reported incidence of sexual risk behaviours, and low use of sexual health services, although the men were receptive to testing services within community settings. Health promotion appears to have impacted upon anal sex, with a consistent decrease in unprotected intercourse compared to very little change observed nationally during this period. Reported intentions to use community testing services are promising, suggesting this may be an effective way of encouraging high-risk groups to engage with their sexual health.