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The organotin (OT) compounds tributyltin (TBT) and triphenyltin (TPhT) are potent biocides that have been used ubiquitously in antifouling paints and pesticides since the mid-1970s. These biocides are extremely toxic to marine life, particularly marine gastropod populations. The European Union therefore took measures to reduce the use of TBT-based antifouling paints on ships and ultimately banned these paints in 2003. Despite sufficient data on OT concentrations in marine gastropods, data are scarce for other species such as the North Sea brown shrimp (Crangon crangon), a dominant crustacean species in North Sea inshore benthic communities. The present study provides the first spatial overview of OT concentrations in North Sea brown shrimp. We have compared these data with historical concentrations in shrimp as well as with sediment concentrations. We have also addressed the effect on the shrimp stock and any human health risks associated with the OT concentrations found. TBT and TPhT in shrimp tail muscle ranged from 4 to 124 and from 1 to 24 µg kg(-1) DW, respectively. High levels are accumulated in estuarine areas and are clearly related with sediment concentrations (biota-sediment accumulation factor ~10). Levels have decreased approximately 10-fold since the ban took effect, coinciding with a recovery of the shrimp stock after 30 years of gradual regression. Furthermore, the OT levels found in brown shrimp no longer present a human health risk.

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The effect of dietary supplementation with N,N-dimethylglycine sodium salt (Na-DMG) was evaluated in a feeding trial with 1500 1-day-old broiler chicks (Cobb 500). DMG was supplemented at 0, 0.1, 0.2, 0.5 or 1 g Na-DMG/kg feed to a ration with either animal fat (chicken fat) or vegetal fat (soy oil) as main fat source. In the vegetal fat diets, production value was significantly linearly improved by supplementation with DMG up to 11%. Irrespective of dietary fat source, abdominal fat percentage was significantly linearly reduced up to 24% and meat yield tended to increase linearly with DMG level up to 4%. In the vegetal fat groups, DMG significantly lowered abdominal fat pad by up to 38% and tended to increase meat yield up to 6% at the highest dose. Fasted non-esterified fatty acid level significantly decreased with increasing DMG level up to 36% and thiobarbituric acid reactive species (TBARS) decreased with a statistical trend up to 46% at the highest dose. In vegetal fat diets, addition of DMG resulted in significant lower TBARS level by 56% at the highest dose. Finally, a significant quadratic effect on ascites heart index was present in the vegetal fat diets, with a minimal value at 0.5 g Na-DMG/kg. In conclusion, dietary supplementation with DMG may improve technical and slaughter performance, and may reduce oxidative stress and pulmonary hypertension, but the degree of effects is modulated by fatty acid profile of the diet. Herewith, effects are more pronounced in a diet rich in polyunsaturated fatty acids compared with a diet rich in saturated and monounsaturated fatty acids.

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N,N-dimethylglycine (DMG) is an intermediary metabolite in cellular choline and betaine metabolism. The present trial aimed to evaluate the effect of dietary DMG on nutrient digestibility and development of pulmonary hypertension syndrome in broilers. A total of 64 14-day-old broiler hens (Ross-308) were raised until age 40 days under cold environmental temperature conditions (15 °C) and were fed a high energy feed in order to incite pulmonary hypertension. Birds were randomly assigned to two groups of which each group had eight replicate pens of four birds each. Test diets contained 0 or 167 mg Na-DMG (Taminizer(®) D; Taminco N.V., Ghent, Belgium)/kg feed. N,N-dimethylglycine supplementation resulted in a significant improvement in apparent faecal digestibility of crude protein and nitrogen-free extract. Further, fulminant ascites was numerically lowered by DMG and incidence of pulmonary hypertension decreased significantly from 44.8% in the control group to 14.6% in the DMG group. Finally, fasted plasma level of non-esterified fatty acids (NEFA) was twofold in the control group in relation to the DMG group. In conclusion, these data demonstrate beneficial effects of DMG on digestibility of non-fat fractions, on fat metabolism and on progression towards broiler ascites syndrome.

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BACKGROUND: Although it has been suggested that elevation of CK-MB after percutaneous coronary intervention is associated with adverse clinical outcomes, limited data are available in the setting of coronary bypass grafting. The aim of the present study was to determine the incidence, predictors, and prognostic significance of CK-MB elevation following multivessel coronary bypass grafting (CABG). METHODS AND RESULTS: The population comprises 496 patients with multivessel coronary disease assigned to CABG in the Arterial Revascularization Therapies Study (ARTS). CK-MB was prospectively measured at 6, 12, and 18 hours after the procedure. Thirty-day and 1-year clinical follow-up were performed. Abnormal CK-MB elevation occurred in 61.9% of the patients. Patients with increased cardiac-enzyme levels after CABG were at increased risk of both death and repeat myocardial infarction within the first 30 days (P=0.001). CK-MB elevation was also independently related to late adverse outcome (P=0.009, OR=0.64). CONCLUSIONS: Increased concentrations of CK-MB, which are often dismissed as inconsequential in the setting of multivessel CABG, appear to occur very frequently and are associated with a significant increase in both repeat myocardial infarction and death beyond the immediate perioperative period.

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The concentrations and distribution of 13 priority volatile organic compounds (VOCs) were determined in sediments of the Scheldt estuary and the Belgian continental shelf, using a modified Tekmar LSC 2000 purge-and-trap system coupled to GC-MS. The method allows a sample intake of up to 50 g wet weight and detection limits are between 0.003 ng/g (tetrachloromethane) and 0.16 ng/g (m- and p-xylene). The repeatability (n = 5) varied between 4% (benzene) and 17% (toluene) and the recoveries ranged from 59% (1,1-dichloroethane) to 99% (tetrachloromethane). Because of the nature of the contaminants, special attention was paid to analyte losses and contamination of the samples during storage aboard the research vessel. Spiked sediment samples were prepared in the laboratory and stored aboard under the same conditions as the environmental samples. The recoveries for these samples varied between 94 and 130%, which suggests that storage had no adverse effect on the samples. No detectable VOC concentrations were found for most of the sampling stations. However, in the Antwerp harbour area, significant concentrations of VOCs were found. The sorption behaviour as predicted from laboratory equilibrium partitioning experiments gives an indication of the in situ partitioning behaviour of VOCs. Although VOCs in sediments should, in general, not be regarded as a major problem in the marine environment, high local concentrations may be a cause of concern.

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The reoccurrence of water molecules in crystal structures of RNase T1 was investigated. Five waters were found to be invariant in RNase T1 as well as in six other related fungal RNases. The structural, dynamical, and functional characteristics of one of these conserved hydration sites (WAT1) were analyzed by protein engineering, X-ray crystallography, and (17)O and 2H nuclear magnetic relaxation dispersion (NMRD). The position of WAT1 and its surrounding hydrogen bond network are unaffected by deletions of two neighboring side chains. In the mutant Thr93Gln, the Gln93N epsilon2 nitrogen replaces WAT1 and participates in a similar hydrogen bond network involving Cys6, Asn9, Asp76, and Thr91. The ability of WAT1 to form four hydrogen bonds may explain why evolution has preserved a water molecule, rather than a side-chain atom, at the center of this intricate hydrogen bond network. Comparison of the (17)O NMRD profiles from wild-type and Thr93Gln RNase T1 yield a mean residence time of 7 ns at 27 degrees C and an orientational order parameter of 0.45. The effects of mutations around WAT1 on the kinetic parameters of RNase T1 are small but significant and probably relate to the dynamics of the active site.

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PCB levels in cod, flounder, mussel and shrimp, covering a ten-year period, were assessed for temporal trends and their relation to biological parameters. A significant relation was found between the PCB levels on a wet weight basis and the total lipid content. Normalising on the total lipid content reduced the differences in PCB levels between the organisms and between different tissues within the organisms. A general downward trend was observed for the PCB levels on the Belgian continental shelf.

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A comparative evaluation of vaccination methods with glycoproteins for the induction of immune responses and protection of the pig against Aujeszky's disease virus (ADV) was performed. Different vaccination routes (intradermal (i.d.) versus intramuscular (i.m.)), inoculation sites (the neck versus the back) and number of inoculation points (2 versus 6) per site were compared. Body weight (BW) changes and viral excretion after challenge were compared with virus-neutralizing titers, antigen-specific IgG and IgA responses in serum and virus-specific lymphoproliferative responses in peripheral blood during the immunisation period. According to BW changes better protection was obtained with six-point than two-point i.d. injections. i.d. vaccination in the back at six points gave similar results as i.m. vaccination in the neck but appeared inferior in the reduction of virus excretion. Regarding the immunological parameters, the virus-specific IgA response in serum gave the best indication for protection. It can be concluded that according to BW changes, six-point i.d. immunisation in the back and i.m. immunisation in the neck provided the best protection and that six-point i.d. injections resulted in a better vaccination than two-point i.d. injections.

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Computerised tomography, used as a diagnostic tool for atrophic rhinitis in pigs, facilitated the macroscopic grading of the nasal structures in live pigs of any age. The results of sequential scans in normal and affected pigs are described; transient atrophy of the ventral conchae was observed in one pig.

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A single injection of 1500 IU of human chorionic gonadotrophin (hCG) in normal men, induced a block in the conversion of 17-hydroxyprogesterone (17-OHP) to testosterone (T) which reached its maximum 24 h after hCG loading. One week after hCG administration both basal 17-OHP (3.8 +/- 0.6 vs 5.1 +/- 0.5 nmol/l, P less than 0.02) and T levels (15.1 +/- 1.7 vs 18.5 +/- 2.3 nmol/l, P less than 0.05) were about 20% lower than before hCG exposure. The ratio 17-OHP to T (0.29 +/- 0.04 vs 0.31 +/- 0.04, P greater than 0.10) was however similar, suggesting recovery from the prior 17,20-lyase suppression at a lower overall capacity of T synthesis. hCG administration one week after the priming dose elicited an increase in the ratio 17-OHP to T, which was about twice as high as after the first hCG injection. Together the data suggest: 1) suppression of testicular steroidogenesis proximal to 17-OHP one week after hCG priming, 2) enhanced hCG induced 17,20-lyase suppression one week after hCG exposure.

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A severe outbreak of Trichuris suis infection in piglets is described. Fifteen per cent of the animals died and the morbidity, characterised by weight loss and diarrhoea, was over 50 per cent. The severity of symptoms observed in naturally infected pigs was related to the number of whipworms. A chemotherapeutic trial was worked out with flubendazole mixed in food for naturally infected and artificially infected piglets. Flubendazole at 30 ppm for five consecutive days controlled the infection in the pigs. Immature T suis in artificially infected pigs were also controlled at the same dose administered for 10 consecutive days.

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Twenty-three patients with twenty-six congenital hip dislocations treated by the Ferguson procedure were reviewed. The study was undertaken to determine if this method of treatment has any effect on the incidence of avascular necrosis of the femoral head and if there are preoperative factors that can assist in predicting the success of treatment. Clinical and roentgenographic criteria were utilized and only dislocations of the hip unassociated with other disorders were included. Avascular necrosis did not occur in these patients during the period studied. It was also found that patients who were more than twelve months old at the time of operation and had a acetabular index of 40 degrees or more had a high incidence of redislocation.

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