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.

Oral and intestinal mucositis - causes and possible treatments.

Abstract: Chemotherapy and radiotherapy, whilst highly effective in the treatment of neoplasia, can also cause damage to healthy tissue. In particular, the alimentary tract may be badly affected. Severe inflammation, lesioning and ulceration can occur. Patients may experience intense pain, nausea and gastro-enteritis. They are also highly susceptible to infection. The disorder (mucositis) is a dose-limiting toxicity of therapy and affects around 500 000 patients world-wide annually. Oral and intestinal mucositis is multi-factorial in nature. The disruption or loss of rapidly dividing epithelial progenitor cells is a trigger for the onset of the disorder. However, the actual dysfunction that manifests and its severity and duration are greatly influenced by changes in other cell populations, immune responses and the effects of oral/gut flora. This complexity has hampered the development of effective palliative or preventative measures. Recent studies have concentrated on the use of bioactive/growth factors, hormones or interleukins to modify epithelial metabolism and reduce the susceptibility of the tract to mucositis. Some of these treatments appear to have considerable potential and are at present under clinical evaluation. This overview deals with the cellular changes and host responses that may lead to the development of mucositis of the oral cavity and gastrointestinal tract, and the potential of existing and novel palliative measures to limit or prevent the disorder. Presently available treatments do not prevent mucositis, but can limit its severity if used in combination. Poor oral health and existing epithelial damage predispose patients to mucositis. The elimination of dental problems or the minimization of existing damage to the alimentary tract, prior to the commencement of therapy, lowers their susceptibility. Measures that reduce the flora of the tract, before therapy, can also be helpful. Increased production of free radicals and the induction of inflammation are early events in the onset of mucositis. Prophylactic administration of scavengers or anti-inflammatories can partially counteract or limit some of these therapy-mediated effects, as can the use of cryotherapy. The regular use of mouthwashes, mouth coatings, antibiotics and analgesics is essential, prior to and during loss and ablation of the epithelial layer. Granulocyte-macrophage colony-stimulating factor/granulocyte colony-stimulating factor or the use of laser light therapy may aid restitution and repair. Glutamine supplements may be beneficial in the repair/recovery phase.

Phenotypic drift in human tenocyte culture.

Abstract: Tendon ruptures are increasingly common, repair can be difficult, and healing is poorly understood. Tissue engineering approaches often require expansion of cell numbers to populate a construct, and maintenance of cell phenotype is essential for tissue regeneration. Here, we characterize the phenotype of human Achilles tenocytes and assess how this is affected by passaging. Tenocytes, isolated from tendon samples from 6 patients receiving surgery for rupture of the Achilles tendon, were passaged 8 times. Proliferation rates and cell morphology were recorded at passages 1, 4, and 8. Total collagen, the ratio of collagen types I and III, and decorin were used as indicators of matrix formation, and expression of the integrin beta1 subunit as a marker of cell-matrix interactions. With increasing passage number, cells became more rounded, were more widely spaced at confluence, and confluent cell density declined from 18,700/cm2 to 16,100/cm2 ( p = 0.009). No change to total cell layer collagen was observed but the ratio of type III to type I collagen increased from 0.60 at passage 1 to 0.89 at passage 8 ( p < 0.001). Decorin expression significantly decreased with passage number, from 22.9 +/- 3.1 ng/ng of DNA at passage 1, to 9.1 +/- 1.8 ng/ng of DNA at passage 8 ( p < 0.001). Integrin expression did not change. We conclude that the phenotype of tenocytes in culture rapidly drifts with progressive passage.

Nitrogen cycling in the gut

Abstract: This review examines the involvement of the gastrointestinal tract in the utilization of nitrogen, the identities of the nitrogenous substances entering and leaving the gut, and the significance of this recycling in the overall nitrogen economy of the body. It is concerned with nonruminant mammals, including man.

Polyamines in food—implications for growth and health☆

Abstract: Different types of food (fruits, vegetables, meat, and milk products) were analyzed by high pressure liquid chromatography to determine their polyamine (putrescine, spermidine, and spermine) contents. All foods contained some polyamines, although the concentrations in different individual food components were variable. As was established earlier using 14C-labeled putrescine, spermidine, and spermine, polyamines are readily taken up by the gut and enter the systemic circulation. Food appears to constitute a major source of polyamines for humans and animals. The distribution of polyamines in the body, as determined by measuring the accumulation of 14C-spermidine in different tissues of the rat, was correlated with the metabolic activity and growth of particular organs. Thus, phytohemagglutinin induced both extensive hyperplastic growth and the preferential accumulation of labeled spermidine in the gut. Correspondingly, when skeletal muscle growth was promoted by the β-antagonist, clenbuterol, 14C-spermidine was sequestered by the hind leg gastrocnemius muscle. It is concluded that food polyamines are not only necessary for normal body metabolism, but are also used and directed preferentially to tissues and organs that have been stimulated to grow by metabolic signals.

Role of low levels of endogenous estrogen in regulation of bone resorption in late postmenopausal women.

Abstract: Although median levels of bone turnover are increased in postmenopausal women, it is unclear whether the low circulating levels of endogenous estrogen exert a regulatory role on these levels. This issue was evaluated by assessing the effect of a blockade of estrogen synthesis on bone turnover markers in 42 normal women (mean age +/- SD, 69 +/- 5 years) randomly assigned to groups receiving the potent aromatase inhibitor letrozole or placebo for 6 months. Letrozole treatment reduced serum estrone (E1) and estradiol (E2) to near undetectable levels (p < 0.0001). This treatment did not affect bone formation markers but, as compared with the placebo group, increased bone resorption markers (urine 24-h pyridinoline [PYD] by 13.3% [p < 0.05] and 24-h urine deoxypyridinoline [DPD] by 14.2% [p < 0.05]) and decreased serum parathyroid hormone (PTH) by 22% (p = 0.002). These data indicate that in late postmenopausal women even the low serum estrogen levels present exert a restraining effect on bone turnover and support the concept that variations in these low levels may contribute to differences in their rate of bone loss.