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21.
The posttranslational modification sumoylation can have multiple effects on its substrate proteins. We studied a patient with isolated cleft lip and palate and a balanced chromosomal translocation that disrupts the SUMO1 (small ubiquitin-related modifier) gene, resulting in haploinsufficiency. In mouse, we found that Sumo1 is expressed in the developing lip and palate and that a Sumo1 hypomorphic allele manifests an incompletely penetrant orofacial clefting phenotype. Products of several genes implicated in clefting are sumoylated, and the Sumo1 hypomorphic allele interacts genetically with a loss-of-function allele for one of these loci. Thus, sumoylation defines a network of genes important for palatogenesis.  相似文献   
22.
Abstract

Routine batch control of licensed inactivated viral vaccines for poultry usually includes a potency assay as a measure of vaccine efficacy. Potency assays often consist of vaccination‐challenge experiments in the target species or in laboratory animals. Instead of measuring the protection of vaccinated animals against virulent pathogens, the serological response after vaccination can be quantified for some vaccines. In vitro antigen quantification assays would be attractive alternatives for the current potency assays because the time and costs involved could be greatly reduced and animal use could be avoided. Such in vitro assays will only be acceptable when the correlation between results and efficacy or potency has been demonstrated convincingly.

The results of our studies on antigen quantification assays indicate that, in principle, quantification of viral antigens from inactivated oil‐adjuvanted vaccines is feasible and reproducible using specially developed antigen capture ELISAs in combination with specific software for statistical analysis of the ELISA data. We have developed methods to quantify the haemagglutination‐neuraminidase (HN) and fusion (F) proteins of Newcastle disease virus (NDV), the viral protein 3 (VP3) of the infectious bursal disease virus (IBDV), and the spike‐1 (S1) protein of the infectious bronchitis virus (IBV). Vaccination experiments with inactivated ND vaccines indicate that the in vitro quantified HN‐ or F‐proteins of NDV are reliable indicators of the serological response after vaccination.  相似文献   
23.
Three groups of beef cow and calf pairs were studied to determine plasma vitamin E and blood selenium (Se) concentrations of calves at 1 month old. Group 1 was managed on irrigated pasture and calves received no Se/vitamin E injections at birth. Group 2 was managed on irrigated pasture, and the calves were injected with Se/vitamin E at birth. Group 3 was managed on dry foothill grasslands, and these cows were supplemented with 56.3 mg vitamin E and 3 mg Se daily, and the calves received a Se/vitamin E injection at birth. The plasma concentration of vitamin E in group 1 and 2 cows (9.5 +/- 1.24 and 8.43 +/- 1.0 microg/ml, respectively) was significantly higher than that of the group 3 cows (2.28 +/- 0.42 microg/ml; P < 0.05). The blood Se concentrations in group 3 cows (169 +/- 37 ng/ml) were significantly higher than those in group 1 and 2 cows (36.4 +/- 15.9 and 31.1 +/- 12.5 ng/ml, respectively; P < 0.05). Calf Se was highly correlated to cow Se (r = 0.965), and calf vitamin E was moderately correlated to cow vitamin E (r = 0.605). Calf vitamin E concentrations were consistently lower than cow vitamin E concentrations, and many values would be considered deficient.  相似文献   
24.
Objectives— To reclassify canine small intestinal and cecal leiomyoma (LM) and leiomyosarcoma (LMS) into smooth muscle and gastrointestinal stromal tumors (GIST) using histologic and immunohistochemical (IH) analysis and to report clinical findings and survival data.
Study Design— Retrospective review of cases.
Animals— Dogs (n=47) with small intestinal (40 LMS; 7 LM) and 25 dogs with cecal tumors (23 LMS; 2 LM).
Methods— Clinical and survival data were reviewed. Tissue sections were reevaluated for light-microscopic malignancy criteria and examined for expression of SMA, desmin, vimentin, S-100, and CD117 (KIT) by immunohistochemistry.
Results— Reclassification resulted in 2 LM, 9 LMS, 19 GIST, and 17 GIST-like tumors in the small intestine and 23 GIST and 2 GIST-like tumors in the cecum. GIST-like tumors were morphologic and IH identical to GIST but lacked KIT expression. No significant difference in survival was observed for tumor type, location, histologic, or IH characteristics; however, dogs with cecal tumors were significantly older in age, presented more commonly with intestinal perforation and peritonitis, and less commonly with weight loss. Cecal tumors had more histologic malignancy criteria than small intestinal tumors. After excision, 1 and 2 year recurrence-free periods were 80.1% and 67.2% for small intestinal and 83.3% and 61.9% for cecal tumors.
Conclusion— Prognosis for intestinal tumors with histologic smooth muscle appearance is good after excision and not related to tumor type, location, histologic, or IH characteristics.
Clinical Relevance— Clinical importance could not be demonstrated for reclassification, but may be for future treatment, of intestinal smooth muscle or stromal tumors.  相似文献   
25.
The experiment investigated whether the effect of enzyme supplementation on performance and nutrient digestibility is dependent on type of the ingredient(s) used, by incorporating wheat bran (WB), sunflower meal (SFM) and citrus pulp (CP) to a reference diet (REF). Those ingredients are known to be rich in different types of non‐starch polysaccharides (NSP). Diets were supplemented with and without (control) an enzyme mix (phytase 1,000 FTU/kg and xylanase U/kg) according to a 2 × 4 factorial arrangement. In total, 24 tanks (3 replicates/treatment) were used with 30 fish each (Nile tilapia, Oreochromis niloticus; mean initial body weight 41 g). Fish were restrictively fed the experimental diets for 43 days (80% of expected satiation). Enzyme supplementation affected the absolute growth (g/day) and FCR (p < 0.05), improving the growth of fish fed the WB and SFM diets, while fish fed the REF and CP diets did not benefit. NSP, energy, ash, phosphorous and calcium digestibility improved with enzyme supplementation (p < 0.05). There was an interaction effect on all growth parameters, as well as the digestibility of energy and phosphorus (p < 0.05). This indicates that the effectiveness of the enzymes was dependent on the NSP‐rich ingredient used and thus the composition of the NSP fraction.  相似文献   
26.
Microcystins (MCs) are endotoxins produced by cyanobacteria in freshwaters globally. With known potential for human health risks, rapid and effective treatment methods are needed for MCs. Previous studies have shown photocatalysis can achieve rapid half-lives with UV lamps and slurries of TiO2. In this experiment, rates and extents of solar photocatalysis of MCs were measured using bench-scale reactors with fixed films of TiO2 for solutions with a range of cellular:aqueous MC ratios. Since cellular MCs can be removed physically, photocatalysis rates were measured following sand filtration to discern the extent of MC removal post-filtration. Since UV energy drives photocatalysis using TiO2, rates of removal were calculated as a function of cumulative UV insolation and time. For water containing < 10% aqueous MC, filtration removed 90% of total MC, and the subsequent photocatalysis half-life was 0.37 MJ/m2 (or 111 min). For water with ~?50% aqueous MCs, filtration removed 52% of the total MCs, and the average half-life for photocatalysis was 0.38 MJ/m2 (or 138 min). For the >?90% aqueous MC treatment, filtration removed 0% MCs, and the photocatalysis half-life for MCs was 0.37 MJ/m2 (or 135 min). Previous studies have used clarified waters; however, results from this study are likely representative of scenarios with waters containing confounding water characteristics and use of solar light for UV, as anticipated in developing countries with less advanced water treatment methods. Photocatalysis is a rapid and effective process for decreasing concentrations of MCs and could be useful for mitigating risks from MC exposures in drinking water.  相似文献   
27.
28.
Serum concentrations of iodine were determined after cattle were given ethylenediamine dihydriodide (EDDI) orally at dosages ranging from 0.0 (placebo) to 0.77 mg/kg of body weight/day. The serum iodine concentration was correlated with the dosage of EDDI. A rate of 0.11 mg EDDI/kg/day was correlated with serum iodine concentrations (20 to 80 micrograms/dl) previously found to be effective in preventing foot rot in cattle. A linear dose-response curve that was generated could be helpful in predicting dosage of EDDI if the serum iodine concentration is known.  相似文献   
29.
Applications of flow models to tall plant canopies are limited, amongst other factors, by the lack of detailed information on vegetation structure. A method is presented to record 3D vegetation structure and make this information applicable to the derivation of turbulence parameters suitable for flow models. The relationship between wind speed, drag coefficient (C D ) and plant area density (PAD) was experimentally investigated in a mixed conifer forest in the lower part of the Eastern Ore Mountains. Essential information was gathered by collecting multi-level high-frequency wind velocity measurements and a dense 3D representation of the forest was obtained from terrestrial laser scanner data. Wind speed dependence or streamlining was observed for most of the wind directions. Edge effects, i.e. the influence of the here not regarded pressure gradient and the advective terms of the momentum equation, are assumed to cause this heterogeneity. Contrary to the hypothetic shelter effect, which would reduce the drag on sheltered plant parts, the calculated profiles of drag coefficients revealed an increasing C D with PAD (i.e. a dependence on canopy and plant structure).  相似文献   
30.
OBJECTIVE: To determine whether parenteral administration of selenium (Se) to calves and the amount of forage and protein provided to their dams affects unadjusted body weight, adjusted 205-day body weight, and average daily gain (ADG) of suckling beef calves. DESIGN: Randomized controlled field trial. ANIMALS: 151 Hereford-Angus crossbred beef calves. PROCEDURE: Newborn calves, randomly assigned to 1 of 3 groups, served as untreated controls (n = 49) or were given Se (0.05 mg/kg [0.023 mg/lb] of body weight, SC) once within 2 days of birth (55) or within 2 days of birth and on days 70, 114, and 149 (47). Until day 149, cow-calf pairs were pastured in fields in which the amount of available forage was high or low and supplemental protein was or was not provided. Calves were weighed on days 1, 70, 149, and 209. On days 160 and 209, blood was obtained from 33 calves for measurements of Se concentration. RESULTS: Mean consumption of supplemental protein was 0.65 kg/dam/d. Between days 1 and 70, calves that received the first of 4 multiple injections of Se had significantly greater ADG than control calves. Average daily gain for calves given only 1 injection was not significantly different from controls. Between days 70 and 149, ADG of calves increased with dietary supplementation of protein to their dams. CLINICAL IMPLICATIONS: Strategic administration of Se to calves and dietary supplementation of protein to their dams may result in greater ADG in suckling beef calves during specific time intervals.  相似文献   
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