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1.
Cleidocranial dysplasia (CCD) is an autosomal dominant, generalized skeletal dysplasia in humans that has been mapped to the short arm of chromosome 6. We report linkage of a CCD mutation to 6p21 in a large family and exclude the bone morphogenetic protein 6 gene (BMP6) as a candidate for the disease by cytogenetic localization and genetic recombination. CCD was linked with a maximal two-point LOD score of 7.22 with marker D6S452 at theta = 0. One relative with a recombination between D6S451 and D6S459 and another individual with a recombination between D6S465 and CCD places the mutation within a 7 cM region between D6S451 and D6S465 at 6p21. A phage P1 genomic clone spanning most of the BMP6 gene hybridized to chromosome 6 in band region p23-p24 using FISH analysis, placing this gene cytogenetically more distal than the region of linkage for CCD. We derived a new polymorphic marker from this same P1 clone and found recombinations between the marker and CCD in this family. The results confirm the map position of CCD on 6p21, further refine the CCD genetic interval by identifying a recombination between D6S451 and D6S459, and exclude BMP6 as a candidate gene.  相似文献   
2.
Pantoprazole is a specific inhibitor of the H+/K(+)-ATPase of the gastric parietal cell. The dose-dependency of a range of pantoprazole pharmacokinetic characteristics was studied. Twelve healthy male subjects were given 10, 20, 40 and 80 mg pantoprazole intravenously according to a randomized, single blind, 4-period change-over scheme. The area under the concentration vs time curve (AUC) and the maximum serum concentration (Cmax) showed a linear increase in line with the dose. Apparent volume of distribution (Vd area), clearance (Cl) and terminal half-life (t1/2) were independent of the dose. The dose-independent elimination of pantoprazole was attributed to the lack of interaction of the drug with cytochrome P450. In clinical practice, a good predictable response, as well as a low potential for interaction with other drugs might be expected.  相似文献   
3.
In order to test the hypothesis that binding sites of cholera toxin for its receptor, the monosialoganglioside GM1, are shared between adjacent beta-polypeptide chains, two inactive chemical derivatives of the B subunit of cholera toxin (CTB) were prepared and were subsequently used for the construction of hybrid CTB pentamers. One inactive derivative consisted of CTB specifically modified in the single essential Trp-88 residue of each beta-chain. This residue was modified by formylation, a treatment preserving the structural integrity of CTB. The other inactive derivative consisted of CTB specifically succinylated in three amino groups located in or near the receptor binding site. Using [1,4-14C]succinic anhydride for the site-specific succinylation and analysis of radiolabeled tryptic fragments of S-carboxymethylated [14C]sssCTB revealed that the amino groups specifically modified were the alpha-amino group of Thr-1 and the epsilon-amino groups of respectively Lys-34 and Lys-91. Upon submitting equal amounts of formylated CTB and site-specific succinylated CTB to a denaturation-renaturation cycle, hybrid pentamers were formed which in contrast to the parental compounds were able to bind GM1. The affinity of hybrid CTB for GM1, as estimated by a competitive solid-phase radiobinding assay was unexpectedly high and only 2.5-fold lower than that of its native counterpart. The number of active binding sites on hybrid CTB was determined from: (i) titration with the oligosaccharide moiety of GM1 (oligo-GM1) and monitoring the reversal of the Trp fluorescence quenching by iodide ions and (ii) rapid gel filtration over a superdex HR column of a mixture of hybrid CTB and an excess of 3H-labeled oligo-GM1. The data are in agreement with the formation of one active binding per four reconstituted binding sites in hybrid CTB, which is consistent with a random association of CTB monomers during the denaturation-renaturation cycle.  相似文献   
4.
Information on the addition of lipase and/or emulsifiers to less digestible or saturated fat sources, such as tallow or other animal fats, used in swine feeding is very limited. Therefore, in a 4 × 4 Latin square design, the effects of adding lipase (0.05% L5, microbial source) and/or an emulsifier (0.3% Lysoforte) on the apparent ileal (AID) and faecal (AFD) digestibility of the main nutrients and fatty acids in particular were studied with four ileal‐cannulated growing pigs (female, initial live weight 20 kg) fed diets containing barley/soybean meal supplemented with 4% animal fat. The fat source contained 35% saturated (S) and 65% unsaturated (U) fatty acids. All diets were free of antibacterial substances (antibiotics, copper sulphate or zinc oxide beyond requirements), in order to avoid interactions between the parameters studied and the gut flora. Lipase addition did not affect the AID or AFD of fat. However, the digestibility of minor fatty acids (C6:0, C14:0) was significantly improved by lipase at both ileal and faecal level. On the other hand, lipase supplementation (P < 0.05) improved the AID of dry matter (DM) and energy as well as the AFD of DM, organic matter (OM), crude protein (CP), ash and energy. Addition of an emulsifier did not have any significant influence on the AID or AFD of fat, while the AID values of DM, OM, CP and energy as well as the AFD values of DM, OM, CP and ash were significantly (P < 0.05) improved. Adding lipase in combination with an emulsifier to the diets decreased (P < 0.05) the AID and AFD of fat, with minor effects on the AID and AFD of the non‐fat components of the diet. The lack of improvement in the digestion of fat by exogenous lipase and/or emulsifier may be related to the rather high U/S ratio (0.65:0.35) of the animal fat source used and to the mode of incorporation of the emulsifier (no pre‐dispersion in the fat source). Furthermore, during the trial the diets, stored at room temperature, showed a steady increase in their content of free fatty acids (to more than 700 g kg?1 fat), due to endogenous lipase activity, leaving less room for upgrading the digestion of animal fat by exogenous lipase and/or emulsifier. Copyright © 2004 Society of Chemical Industry  相似文献   
5.
The Drosophila segment polarity gene wingless (wg) is essential for cell fate decisions in the developing embryonic epidermis. Wg protein is produced in one row of cells near the posterior of every segment and is secreted and distributed throughout the segment to generate wild-type pattern elements. Ventrally, epidermal cells secrete a diverse array of anterior denticle types and a posterior expanse of naked cuticle; dorsally, a stereotyped pattern of fine hairs is secreted. We describe three new wg alleles that promote naked cuticle cell fate but show reduced denticle diversity and dorsal patterning. These mutations cause single amino acid substitutions in a cluster of residues that are highly conserved throughout the Wnt family. By manipulating expression of transgenic proteins, we demonstrate that all three mutant molecules retain the intrinsic capacity to signal ventrally but fail to be distributed across the segment. Thus, movement of Wg protein through the epidermal epithelium is essential for proper ventral denticle specification and this planar movement is distinct from the apical-basal transcytosis previously described in polarized epithelia. Furthermore, ectopic overexpression of the mutant proteins fails to rescue dorsal pattern elements. Thus we have identified a region of Wingless that is required for both the transcytotic process and signal transduction in dorsal cell populations, revealing an unexpected link between these two aspects of Wg function.  相似文献   
6.
This study investigates factors associated with Campylobacter contamination of broiler carcasses, using survey data collected from nine Belgian slaughterhouses in 2008 in accordance with a European Union baseline study. Campylobacter were detected in 51.9% (202/389) (95% confidence interval, 46.8%-56.9%) of broiler carcasses. Campylobacter concentration was <10 CFU/g in 49.6% of carcasses, while 20.6% were contaminated with ≥1000 CFU/g. The mean Campylobacter concentration, as calculated by maximum likelihood estimation for left-censored data, was 1.8 log10 CFU/g, with a standard deviation of 1.9 log10 CFU/g. There was statistically significant variation among slaughterhouses in prevalence and concentrations of Campylobacter in their sampled carcasses. Campylobacter prevalence (but not concentrations) was positively associated with increase in broilers age. Both Campylobacter prevalence and concentration were significantly higher in carcasses sampled during June and September (but not in July and August) than carcasses sampled in January. We also investigated the correlation (Spearman’s rank correlation test) between the scores of official control inspections and Campylobacter prevalence for eight out of the nine slaughterhouses. The control inspections were routinely performed by the Belgian Federal Agency for the Safety of the Food Chain, and the concluded inspection scores were used as a general numerical indicator for the status of operational hygiene and quality of management in the slaughterhouses. Ranking of slaughterhouses based on their inspection scores was statistically correlated (Spearman’s correlation coefficient = 0.857) with their ranking based on prevalence of Campylobacter. In the present study we demonstrate how the outcomes from a routine baseline survey could be coupled with other readily available data from national control authorities in order to enable a better insight over Campylobacter contamination status in broiler slaughterhouses. Findings from this work call for subsequent in-depth investigations on technical and hygiene management factors that could impact Campylobacter contamination across broiler slaughterhouses.  相似文献   
7.
Garden cress, sesame, radish, and mustard seeds immersed in water were treated with high pressure (250, 300, 350, and 400 MPa) for 15 min at 20 degrees C. After treatment, percentages of seeds germinating on water agar were recorded for up to 11 days. Of the seeds tested, radish seeds were found to be the most pressure sensitive, with seeds treated at 250 MPa reaching 100% germination 9 days later than untreated control seeds did. Garden cress seeds, on the other hand, were the most pressure resistant, with seeds treated at 250 MPa reaching 100% germination 1 day later than untreated control seeds did. Garden cress sprouts from seeds treated at 250 and 300 MPa also took about 1 day longer to reach average sprout length than sprouts from untreated control seeds did, indicating that sprout growth was not retarded once germination had occurred. Garden cress seeds were inoculated with suspensions of seven different bacteria (10(7) CFU/ml) and processed with high pressure. Treatment at 300 MPa (15 min, 20 degrees C) resulted in 6-log reductions of Salmonella Typhimurium, Escherichia coli MG1655, and Listeria innocua, > 4-log reductions of Shigella flexneri and pressure-resistant E. coli LMM1010, and a 2-log reduction of Staphylococcus aureus. Enterococcus faecalis was virtually not inactivated. For suspensions of the gram-positive bacteria, similar levels of inactivation in water in the absence of garden cress seeds were found, but the inactivation of E. coil LMM1010 and S. flexneri in water in the absence of garden cress seeds was significantly less extensive. These data suggest that garden cress seeds contain a component that acts synergistically with high hydrostatic pressure against gram-negative bacteria.  相似文献   
8.
BACKGROUND: Limited research suggests that brown seaweed (extracts) may be used in pig nutrition for improving gut health and performances and for iodine enrichment of tissues. One in vitro and two in vivo experiments with dried iodine‐rich intact marine seaweed (Ascophyllum nodosum) have been conducted with weaned piglets to further unravel the mechanisms. RESULTS: In vitro investigations revealed a statistically significant depressive effect of seaweed on pig gut flora, especially on Escherichia coli. In vivo, seaweed (10 g kg?1) had a reducing effect on the E. coli load in the stomach (P = 0.07) and small intestine (P < 0.05), while the lactobacilli/E. coli ratio was enhanced (P < 0.05) in the small intestine, indicating a beneficial shift in the microbial population. Statistically significant increases (P < 0.001) in iodine content were noted for several tissues in piglets on seaweed (20 g kg?1, corresponding to 10 mg iodine kg?1 feed) compared with the control diet (1 mg iodine kg?1 feed). CONCLUSION: Intact A. nodosum brown seaweed may be introduced in pig nutrition as a feed material with a double strategy: improvement of pig gut health and performances and iodine enrichment of porcine tissues. This feeding strategy may alleviate, but not solve, the actual iodine deficiency in Belgium. Copyright © 2009 Society of Chemical Industry  相似文献   
9.
Lipid composition of normal and hypertrophic bovine thyroids   总被引:1,自引:0,他引:1  
The phospholipid content of bovine thyroid tissue amounts to 70% of total lipid. Triglycerides and cholesterol are the main neutral lipids. Only trace amounts of free fatty acid and esterified cholesterol are found, while two not yet identified components also are present. The distribution of lipid phosphorus in the different phospholipid classes is as follows: phosphatidyl choline, 43.0%; phosphatidyl ethanolamine, 25.2%; phosphatidyl serine, 5.6%; phosphatidyl inositol, 6.5%; sphingomyelin, 14.0%; cardiolipin, 2.8%; lysophosphatidyl choline, <1%; and phosphatidic acid, <1%. The phosphatidyl ethanolamines are rich in plasmalogens. The fatty acid patterns in the different lipid classes are reported. The essential differences between normal and hypertrophic bovine thyroid tissue are higher water content and lower triglyceride and sphingomyelin values for hypertrophic tissue.  相似文献   
10.
Infections with non-typhoid Salmonella represent a major problem in industrialized countries.The emergence and spread of antimicrobial-resistant pathogens, among them Salmonella, has become a serious health hazard worldwide. One of the most commonly isolated non-typhoid Salmonella serovars in pigs, pork and humans is Salmonella Typhimurium. In this study the comparison of the incidences of resistance to nine antimicrobials, resistance patterns and phage types between S. Typhimurium isolated from pigs (n = 581), pork (n = 255) and humans (n = 1870) in Belgium in the period 2001 to 2006 was performed.Resistance to the antimicrobials ampicillin, chloramphenicol, streptomycin, sulfonamides and tetracycline was frequently observed and varied between 23.5% and 83.1%. Resistance ranged from 15.6% to 20.7% for the combination trimethoprim–sulfonamides and from 3.4% to 5.8% for nalidixic acid. Resistance to the critical important antimicrobials cephalosporins and fluoroquinolones was found sporadically (≤ 1.2%). Resistance to the different antimicrobials was observed to be similar in S. Typhimurium isolates from the various origins. Twenty-seven antimicrobial resistance patterns representing in total 75.2%, 89.0% and 89.6% of the isolates from pigs, pork and humans respectively were found to be common among the three groups and 73 combinations antimicrobial resistance pattern/phage type were found to be common among pork and human isolates, representing 70.1% of the pork isolates and 51.0% of the human isolates. The high percentage of isolates that have a common resistance pattern, and in a less pronounced way a common combination phage type/resistance pattern, are in agreement with the hypothesis of transfer of antimicrobial resistant Salmonella from pigs via the consumption of pork to humans as one of the possible pathways. The most prevalent combination in Belgium within both the pork isolates (7.4%) and the human isolates (13.2%) was S. Typhimurium DT104 resistant to ampicillin, chloramphenicol, streptomycine, sulfonamides and tetracycline.  相似文献   
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