Institution
Rowett Research Institute
About: Rowett Research Institute is a based out in . It is known for research contribution in the topics: Rumen & Population. The organization has 2986 authors who have published 4459 publications receiving 239472 citations.
Topics: Rumen, Population, Leptin, Amino acid, Adipose tissue
Papers published on a yearly basis
Papers
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TL;DR: There is now evidence that the conversion of nitrate into oxides of nitrogen prevents the formation carcinogenic nitrosamines, and a reevaluation of the currently very negative perception of dietary nitrates is needed.
151 citations
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TL;DR: It is confirmed that PIF acts directly to stimulate the proteasome pathway in muscle cells and may play a pivotal role in protein catabolism in cancer cachexia.
Abstract: Loss of skeletal muscle is a major factor in the poor survival of patients with cancer cachexia. This study examines the mechanism of catabolism of skeletal muscle by a tumour product, proteolysis-inducing factor (PIF). Intravenous administration of PIF to normal mice produced a rapid decrease in body weight (1.55 +/- 0.12 g in 24 h) that was accompanied by increased mRNA levels for ubiquitin, the Mr 14 000 ubiquitin carrier-protein, E2, and the C9 proteasome subunit in gastrocnemius muscle. There was also increased protein levels of the 20S proteasome core and 19S regulatory subunit, detectable by immunoblotting, suggesting activation of the ATP-ubiquitin-dependent proteolytic pathway. An increased protein catabolism was also seen in C(2)C(12)myoblasts within 24 h of PIF addition with a bell-shaped dose-response curve and a maximal effect at 2-4 nM. The enhanced protein degradation was attenuated by anti-PIF antibody and by the proteasome inhibitors MG115 and lactacystin. Glycerol gradient analysis of proteasomes from PIF-treated cells showed an elevation in chymotrypsin-like activity, while Western analysis showed a dose-related increase in expression of MSSI, an ATPase that is a regulatory subunit of the proteasome, with a dose-response curve similar to that for protein degradation. These results confirm that PIF acts directly to stimulate the proteasome pathway in muscle cells and may play a pivotal role in protein catabolism in cancer cachexia.
150 citations
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TL;DR: The mechanism of lectin toxicity in this instance is analogous to that known to occur in the rat, namely that the ingested lectin causes disruption of the epithelial cells of the larval midgut leading to breakdown of the transport of nutrients into these cells, and the absorption of potentially harmful substances.
Abstract: Seeds of the kidney bean (Phaseolus vulgaris) are toxic to developing larvae of the bruchid beetle (Callosobruchus maculatus), a major storage pest of many legumes. Insect feeding trials were carried out whereby the albumin and globulin protein fractions from seeds of P. vulgaris were incorporated into artificial seeds. Both fractions were shown to be toxic and to contain haemagglutinating activity, implicating the seed lectins as being involved in seed resistance. Further feeding trials using different P. vulgaris lectin preparations confirmed the toxicity of these lectins and suggested that it was the E-type lectin subunits (erythrocyte-binding) which were the major antimetabolites. Indirect immunofluorescence investigations using monospecific antisera for globulin lectins showed that the lectins, when ingested by the larvae, bound to the midgut epithelial cells. It was suggested that the mechanism of lectin toxicity in this instance is analogous to that known to occur in the rat, namely that the ingested lectin causes disruption of the epithelial cells of the larval midgut leading to breakdown of the transport of nutrients into these cells, and the absorption of potentially harmful substances. This is the first time that evidence for the mechanism of lectin toxicity has been obtained in insects.
149 citations
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TL;DR: It is suggested that the species differences in endogenous purine derivative excretion were probably due to the different profiles of xanthine oxidase activity in tissues and particularly in the blood, by increasing the probability of degradation to compounds which could not be salvaged.
Abstract: The endogenous urinary excretion of the purine derivatives allantoin, uric acid and xanthine plus hypoxanthine were measured in twenty-nine lambs, ten cattle (six steers, one cow and three preruminant calves) and four pigs. The sheep and mature cattle were nourished by intragastric infusion and the calves were given a milk-substitute. The pigs were fed on a purine-free diet. The excretion of total purine derivatives was substantially greater by the cattle, being 514 (SE 20.6) mumol/kg live weight (W)0.75 per d compared with 168 (SE 5.0) mumol/kg W0.75 per d by the sheep and 166 (SE 2.6) mumol/kg W0.75 per d by the pigs. Plasma from normally fed sheep, cows and pigs was incubated with either xanthine or uric acid. Sheep and pig plasma had no xanthine oxidase (EC 1.2.3.2) activity whereas plasma from cattle did. Uricase (EC 1.7.3.3) was not present in plasma of cattle and pigs and appeared to be present in trace amounts only in sheep plasma. It is suggested that the species differences in endogenous purine derivative excretion were probably due to the different profiles of xanthine oxidase activity in tissues and particularly in the blood. This is because a high xanthine oxidase activity would reduce the chance to recycle purines, by increasing the probability of degradation to compounds which could not be salvaged.
149 citations
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TL;DR: In each instance the increases in values obtained with increasing level of casein infusion were significant, and the possible protein limitations for cows in negative energy balance were discussed.
Abstract: 1. Two experiments were carried out with lactating Friesian cows with a potential for high milk production. Within 3 d after calving they were fitted with a catheter to allow infusions to be given into the abomasum. During each experiment the milk yields and intake of the cows were such that they were calculated to be in negative energy balance.2. In the first experiment three cows were infused daily with 10 l, the infusate being water, a suspension providing 300 g casein, or a solution providing 300 g glucose. The cows were offered a diet of barley straw, rolled barley and urea ad lib. during the first 60 d, after which they were fed to a calculated yield of 7 kg fat-corrected milk (FCM) less than their previous yield to ensure a negative energy balance. Infusion of casein increased yield by up to 3 kg FCM in comparison with glucose or water infusion. It also increased the concentration of crude protein in milk by approximately 13%. There was no consistent effect on milk fat concentration.3. In the second experiment four cows were used in a trial of Latin-Square design. The basal ration was sufficient for a yield of 10 kg FCM/d. Four levels of casein and glucose infused into the abomasum daily were (g) 0, 750; 250, 500; 500, 250; 750, 0. The yields of FCM (kg/d) were 18.9, 22.7, 25.2 and 26.1, the concentration of protein (g/kg) was 25.2, 28.4, 29.6 and 31.5 and the concentration of milk fat (g/kg) was 48.2, 49.8, 51.0 and 54.8 for the four treatments respectively. In each instance the increases in values obtained with increasing level of casein infusion were significant. Infusion of casein was calculated to increase the extent of net energy deficit from 20.5 to 41.0 MJ/d. The possible protein limitations for cows in negative energy balance were discussed.
148 citations
Authors
Showing all 2986 results
Name | H-index | Papers | Citations |
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Sundeep Khosla | 115 | 544 | 55451 |
Andrew Collins | 100 | 684 | 40634 |
Harry J. Flint | 99 | 293 | 43712 |
Alan Crozier | 95 | 338 | 29741 |
William M. O'Fallon | 95 | 187 | 29373 |
John R. Speakman | 95 | 667 | 34484 |
Boris Zhivotovsky | 92 | 358 | 50297 |
Michael E. J. Lean | 92 | 411 | 30939 |
Nigel W. Bunnett | 91 | 348 | 31214 |
John D. Hayes | 86 | 257 | 33146 |
Ruth McPherson | 85 | 305 | 50535 |
Bernard Portmann | 85 | 326 | 26442 |
Olle Ljungqvist | 84 | 340 | 28386 |
Michael H. Hastings | 78 | 226 | 23486 |
Ronald J. Maughan | 78 | 360 | 18100 |