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Item Prevalence and production impacts of subclinical mastitis in extensively managed ewes(Montana State University - Bozeman, College of Agriculture, 2019) Knuth, Ryan Michael; Chairperson, Graduate Committee: Megan Van Emon; W. C. Stewart, J. B. Taylor, C. J. Yeoman, B. Bisha, M. L. Van Emon and T. W. Murphy were co-authors of the article, 'The prevalence and etiology of subclinical mastitis and association with milk somatic cell count in western range flocks' submitted to the journal 'Journal of animal science' which is contained within this thesis.; W. C. Stewart, J. B. Taylor, C. J. Yeoman, M. L. Van Emon and T. W. Murphy were co-authors of the article, 'Udder morphometry and health and their relationship with ewe somatic cell count and productivity in extensively manged research flocks' submitted to the journal 'Journal of animal science' which is contained within this thesis.Mastitis results from a bacterial infection of the mammary gland and is a devastating disease to all sheep producers from both an economic and animal welfare perspective. Clinically infected ewes display visually apparent symptoms, however, subclinically infected ewes do not although this form is more common. Since milk is a direct commodity of dairy animals, much of the past research has been conducted here and the production and economic impacts of subclinical mastitis are less clear in non-dairy (e.g., meat- and wool-type) ewes. The objectives of the first study were to identify bacteria species present in milk collected from clinically healthy ewes and evaluate somatic cell count (SCC) thresholds relating to intramammary infection. Milk samples were collected from two research flocks in the Western U.S. (Montana State University = MSU; U.S. Sheep Experiment Station = USSES). Bacteria were identified by both culturing and identification via mass spectrometry and polymerase chain reaction methods. Overall, 60 bacteria species were identified using mass spectrometry and the most common belonged to the Bacillus and Staphylococcus genera. The ideal SCC thresholds to predict intramammary infection ranged between 240 x 10 3 to 1370 x 10 3 cells/mL, depending on the flock and time of collection. In the second study, milk samples were collected and udder and teat morphometric traits were observed to predict ewe productivity via dam 120 day adjusted litter weaning weight (LW120). Udder and teat characteristics were assessed on a linear scale at each sampling and included teat length, udder symmetry, and presence of supernumerary teats, to name a few. The effect of log10-transformed SCC (LSCC) on ewe productivity was dependent on lactation stage and production year, but when significant, indicated a 9.2-14.7 kg reduction in LW120 associated with a 1-unit increase in LSCC. Factors which influenced LSCC included parity, production year, and presence of supernumerary teats in USSES ewes and, for MSU ewes, included teat length, external teat damage, udder symmetry, and presence of supernumerary teats. The results indicate subclinical mastitis is common and additional studies investigating techniques to mitigate its severity and prevalence in meat- and wool-type ewes are warranted.Item Breast and cervical health awareness project : dissemination of information to older rural women(Montana State University - Bozeman, College of Nursing, 1997) Grossman, Linda Lee; Chairperson, Graduate Committee: Kathleen ChafeyItem Making meaning of the experience of breast cancer(Montana State University - Bozeman, College of Education, Health & Human Development, 1996) Nelson, TamaraItem Differences in accuracy detecting breast cancer between mammography and stress thermography as determined by breast biopsy(Montana State University - Bozeman, College of Nursing, 1981) Bradshaw, Bridget SueItem Novel compounds inhibiting HIV infection, breast cancer metastasis, and bacterial growth(Montana State University - Bozeman, College of Letters & Science, 2012) Shepard, Joyce Brewer; Chairperson, Graduate Committee: Martin Teintze; Royce A. Wilkinson, Jean R. Starkey and Martin Teintze were co-authors of the article, 'Novel compounds containing multiple guanide groups that inhibit breast cancer metastases' in the journal 'International journal for cancer research' which is contained within this thesis.; Royce A. Wilkinson was a main author, and Cassidy Cooper, Sarah K. Walton, Amanda R. Radke, Robert L. Watkins, Thomas J. Wright, Elizabeth Erikson, Mohamed E. Labib, Jovanka M. Voyich, and Martin Teintze were co-authors of the article, 'Broad-spectrum antibacterial activity in novel compounds containing multiple phenylguanide or biguanide groups' in the journal 'Journal of antimicrobial chemotherapy' which is contained within this thesis.We synthesized novel guanide, biguanide, phenylguanide, and naphthyguanide derived compounds on linear, branched, and dendrimer backbones that are effective inhibitors of HIV infection, breast cancer metastasis, and bacterial growth. HIV utilizes CXCR4 as a co-receptor for cellular entry. Blocking CXCR4 inhibits infection with X4 strains of the virus. Initial competition assays demonstrated that some of the phenylguanide compounds bound to CXCR4 with high affinity. The derivatives with high CXCR4 affinity inhibited X4 viral infection, but did not inhibit R5 or X4R5 viruses. Importantly, many cancers overexpress CXCR4, including breast cancer. CXCR4 activation leads to cellular chemotaxis, angiogenesis, and cell survival, all of which promote cancer survival and proliferation. Compounds with high CXCR4 affinity were evaluated for inhibition of breast cancer metastasis. In vitro toxicity of all the derivatives was determined, followed by in vitro migration inhibition. Three derivatives with the best selectivity indexes for CXCR4 were examined in an in vivo lung colony metastasis assay. Spermidine trisphenylguanide (SI = 1785) was evaluated at 50 micrometers, 200 micrometers, and 300 micrometers and showed increasing inhibition of lung metastases (P = 0.34, 0.3, 0.02, respectively). Spermidine bis-2-naphthylguanide (SI = 1230) and spermine tris-2-naphthylguanide (SI = 191) were evaluated at 100 micrometers and showed significant reduction of lung metastases (P = 0.1 and 0.04, respectively). The topical antiseptic biguanide chlorhexidine, is structurally similar to our derivatives. So, the derivatives were tested for antimicrobial activity against drug susceptible and resistant pathogenic Enterococcus, Staphylococcus, Acinetobacter, and Pseudomonas strains. THAM trisphenylguanide, DNT2300 biguanide and phenylguanide, and DNT2200 phenylguanide demonstrated broad spectrum bacteriocidal activity similar to chlorhexidine. Preliminary in vivo studies on mice treated with THAM trisphenylguanide either immediately after methicillin resistant Staphylococcus aureus (MRSA) infection or an hour post MRSA infection showed significant reductions in bacterial burden in the intraperitoneal cavity, heart and kidney in the immediate treatment group and slight reductions of bacterial burden in the one hour treatment group. This data shows the potential for treatment of MRSA infections with the tested compounds. Thus, different subsets of the novel guanide compounds discussed here can inhibit HIV infection, breast cancer metastasis, and bacterial growth.Item Patient's perception of the helpfulness of education materials for breast cancer(Montana State University - Bozeman, College of Nursing, 2008) Heck, Kimberly Keough; Chairperson, Graduate Committee: Clementine RiceBreast cancer is the most widely diagnosed cancer among women and the second leading cause of death after lung cancer. "Many women with cancer describe the moment they found out about their diagnosis as truly devastating" (National Breast Cancer Organization [NBCO], 2000, p.1). There are numerous ways in which women cope during this upsetting time. Two ways to help women cope is to encourage them to understand their new diagnosis through education and exploring all available treatment options. There is a shortage of documentation on breast cancer education and few studies have examined patients' perception of breast cancer education. The target population for this study was adult women with a diagnosis of breast cancer who received treatment from a medium sized northwestern cancer clinic. The population and the sample consisted of residents from urban and rural regions of central Montana. A convenience sample of persons eighteen years and older consisting of the 168 women who are on the breast cancer survivors' monthly mailing at the cancer clinic were invited to participate in the study; the actual sample consisted of 59 women. The sample was self-selecting and participation was voluntary. A descriptive, retrospective, cross-sectional design was used as the framework for this study. The questionnaire that was developed for this study was used to collect data that explored participants' perceptions of the education received. Participants were asked where they received their education about breast cancer and 71.2% said that they received their educational materials from the cancer treatment facility. A large majority (79.7%) indicated that immediately after breast cancer diagnosis they felt ready to learn. Almost half (42.4%) felt acceptance of their breast cancer diagnosis. A total of 63% felt that their educational materials were either very helpful or helpful.