970 resultados para interval type-2 fuzzy logic system (IT2FLS)


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We have recently reported that psychological stress is associated with a shift in the human type-1/type-2 cytokine balance toward a type-2 cytokine response. The mechanisms of these cytokine alterations are unknown, but likely involve glucocorticoid (GC) modulation of cytokine production. Therefore we sought to characterize the effects of GC on the in vitro human type-1/type-2 cytokine balance. We hypothesized that GC induce a type-2 cytokine shift through modulation of critical regulatory cytokines and alterations in the CD28/B7 costimulatory pathway. ^ We first sought to characterize the effect of the GC, dexamethasone (DEX), on type-1 (IFN-γ, IL-12) and type-2 (IL-4, IL-10) cytokine production by human peripheral blood mononuclear blood cells (pBMC) stimulated with a variety of T-lymphocyte and monocyte stimuli. DEX, at concentrations mimicking stress and supraphysiologic levels of cortisol, decreased IFN-γ and IL-12 production and increased IL-4 and IL-10 production, indicating a shift in the type-1/type-2 cytokine balance toward a type-2 response. Furthermore, both CD4+ and CD8+ T-lymphocytes were susceptible to the cytokine modulating effects of DEX. Furthermore, in the absence of the monocyte, the DEX-induced alterations in T-lymphocyte cytokine production were reduced, indicating that the interaction between the monocyte and T-lymphocyte plays a significant role. ^ We next determined the role of regulatory cytokines, known to modulate the type-1/type-2 cytokine balance, in the DEX-induced cytokine alterations. The addition of the recombinant IL-12p70 and IFN-γ, but not the neutralization of IL-4, IL-10 or IL-13 using monoclonal antibodies, attenuated the DEX-induced type-1/type-2 cytokine alterations. These data suggest that the DEX-induced cytokine alterations are mediated, at least in part, through the initial inhibition type-1 cytokines. Lastly, we investigated the role of the CD28/B7 costimulatory pathway in these cytokine alterations. DEX decreased the expression of CD80 and CD86 on THP-1 cells, a monocyte cell line, and the expression of CD28 and CTLA-4 on PHA-stimulated pBMC. The DEX-induced decrease in CD28 and CTLA-4 expression was attenuated by rhIL-12. Finally, CD28 activation attenuated the DEX-induced decrease in IFN-γ production, suggesting that modulation of the CD28/B7 costimulatory pathway may contribute to the DEX-induced type-1/type-2 cytokine alterations. ^

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Diabetes in adults (type 2) has emerged as a world health problem. Prevalence and risk factors have been found to vary in different populations. The wide range of prevalence rates worldwide indicates the importance of genetic and environmental factors in the etiology of the disease. The few available studies suggest that Filipinos are among the higher-risk groups for developing diabetes. This cross-sectional study estimated the overall prevalence rate of type 2 diabetes among Filipino Americans, ages 20–74 years and residents of Houston Metropolitan Statistical Area, Texas, to be 16.1%. The observed high prevalence was associated with age, sex, family history of diabetes, obesity, region of birth; and, in women, gestational diabetes and income. The diabetic Filipino Americans had a higher proportion of parental history of diabetes, medical history of hypertension, and history of smoking; were physically less active, but generally non-obese, compared with the United States diabetic population. ^

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This dissertation was written in the format of three journal articles. Paper 1 examined the influence of change and fluctuation in body mass index (BMI) over an eleven-year period, on changes in serum lipid levels (total, HDL, and LDL cholesterol, triglyceride) in a population of Mexican Americans with type 2 diabetes. Linear regression models containing initial lipid value, BMI and age, BMI change (slope of BMI), and BMI fluctuation (root mean square error) were used to investigate associations of these variables with change in lipids over time. Increasing BMI over time was associated with gains in total and LDL cholesterol and triglyceride levels in women. Fluctuation of BMI was not associated with detrimental lipid profiles. These effects were independent of age and were not statistically significant in men. In Mexican-American women with type 2 diabetes, weight reduction is likely to result in more favorable levels of total and LDL cholesterol and triglyceride, without concern for possible detrimental effects of weight fluctuation. Weight reduction may not be as effective in men, but does not appear to be harmful either. ^ Paper 2 examined the associations of upper and total body fat with total cholesterol, HDL and LDL cholesterol, and triglyceride levels in the same population. Multilevel analysis was used to predict serum lipid levels from total body fat (BMI and triceps skinfold) and upper body fat (subscapular skinfold), while controlling for the effects of sex, age and self-correlations across time. Body fat was not strikingly associated with trends in serum lipid levels. However, upper body fat was strongly associated with triglyceride levels. This suggests that loss of upper body fat may be more important than weight loss in management of the hypertriglyceridemia commonly seen in type 2 diabetes. ^ Paper 3 was a review of the literature reporting associations between weight fluctuation and lipid levels. Few studies have reported associations between weight fluctuation and total, LDL, and HDL cholesterol and triglyceride levels. The body of evidence to date suggests that weight fluctuation does not strongly influence levels of total, LDL and HDL cholesterol and triglyceride. ^

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Evidence suggests that sex-based differences in immune function may predispose women to numerous hypersensitivity conditions such as Systemic lupus erythematosus (SLE), Hashimoto's thyroiditis and asthma. To date, the exact mechanisms of sexual dimorphism in immunity are not fully characterized but sex hormones such as 17-β estradiol (E2) and progesterone (PR) are believed to be involved. Since E2 and PR may modulate the production of critical regulatory cytokines, we sought to characterize their effects on the in vitro human type-1/type-2 cytokine balance. We hypothesized that E2 and/or PR vary cytokine production and influence costimulatory molecule expression and apoptosis. We first described the effect of E2 and/or PR on type-1 (IFN-γ and IL-12) and type-2 (IL-4 and IL-10) cytokine production by human peripheral blood mononuclear cells (PBMC) treated with various T-lymphocyte and monocyte stimuli. E2 and/or PR were each used at concentrations similar to those found at the maternal-fetal interface during pregnancy. At this dose, E2 increased IFN-γ and IL-12 production and PR decreased IFN-γ production and tended to increase IL-4 production. Furthermore, the combination of E2+PR decreased IL-12 production. This suggests that E2 shifts the type-1/type-2 cytokine balance towards a type-1 response and that PR and E2+PR shift the balance towards a type-2 response. Next, we used intracellular cytokine detection to demonstrate that E2 and/or PR are capable of altering cytokine production of CD3+ T-cells and the CD3+CD4+ and CD3+CD8+ subsets. In addition, we used the H9 T-lymphocyte cell line and the THP-1 monocyte cell line to show that E2 and/or PR can induce cytokine effects in both T-cells and monocytes independent of their interaction. Lastly, we determined the effect of E2 and/or PR on costimulatory molecule expression and apoptosis as potential mechanisms for the cytokine-induced alterations. E2 increased and PR decreased CD80 expression on THP-1 cells and PR and E2+PR decreased CD28 expression in PBMC and Jurkat cells. Furthermore, E2, PR and E2+PR increased Fas-mediated apoptosis in Jurkat cells and E2 increased FasL expression on THP-1 cells. Thus, E2 and/or PR may alter the cytokine balance by modulating the CD28/CD80 costimulatory pathway and apoptosis. ^

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Purpose. This cross-sectional, observational study explored differences among groups staged for intent to decrease dietary fat intake in women with type 2 diabetes in relation to demographic, weight concern, physiological, and psychosocial variables. ^ Methods. A sample of 100 community-dwelling, English-speaking women, who were over age 30 and had type 2 diabetes for at least a year, was accessed through a culturally diverse endocrinology clinic. Subjects completed 7 self-report instruments: demographic sheet, with 11-point weight satisfaction scale; staging algorithm; fat intake (MEDFICTS); depression (CES-D); diabetes-specific dietary knowledge (ADKnowl), social support and self-efficacy scales (SE-Type 2). Physiological variables were abstracted from the medical record (HbA 1c, blood pressure, serum cholesterol and triglycerides). ^ Results. The women's average age was 57.69 years ( SD = 3.07); 50% were married. Subjects were well-educated ( M = 14 years; SD = 3.33), with average diabetes duration of 10.57 years (SD = 9.11), high body mass index (M = 35.72; SD = 8.36), low diabetes-specific dietary knowledge, low weight satisfaction, but in good diabetes control. Racial/ethnic composition was 44% non-Hispanic-White-American, 18% Hispanic-White-American, 15% non-Hispanic-African-American, 16% Hispanic-African-American and 5% other. Fat intake was low and differed by racial/ethnic demographics. The highest fat intake scores were for non-Hispanic-African-Americans (M = 53), followed by Hispanic-White-Americans (M = 51), non-Hispanic-White-Americans (M = 45), and Hispanic-African-Americans (M = 32), who had the lowest fat intake scores. ^ MANOVA analyses revealed no significant differences between stages of behavior change in relation to psychosocial or weight concern variables, age, education, HbA1c, or cholesterol levels. Single women were more likely to be in the three preaction stages (precontemplation, contemplation, and preparation); married women were equally distributed across stages (the preaction stages plus action and maintenance). African-American women (Hispanic and non-Hispanic) were more likely in contemplation and preparation. Triglycerides were higher in women in the action stage than contemplation or preparation. Systolic blood pressure was higher in action than preparation; diastolic blood pressure was higher in action than preaction. ^ Conclusions. Healthcare professionals should consider race, ethnicity, and marital status in client interactions. Dietary intake can vary according to both race and ethnicity; collapsing racial/ethnic groups can alter means and distributions, generating faulty conclusions. Further research is warranted to explore relationships between dietary self-care and marital status, race, ethnicity, and physiological variables. ^

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There are many diseases associated with the expansion of DNA repeats in humans. Myotonic dystrophy type 2 is one of such diseases, characterized by expansions of a (CCTG)•(CAGG) repeat tract in intron 1 of zinc finger protein 9 (ZNF9) in chromosome 3q21.3. The DM2 repeat tract contains a flanking region 5' to the tract that consists of a polymorphic repetitive sequence (TG)14-25(TCTG)4-11(CCTG) n. The (CCTG)•(CAGG) repeat is typically 11-26 repeats in persons without the disease, but can expand up to 11,000 repeats in affected individuals, which is the largest expansion seen in DNA repeat diseases to date. This DNA tract remains one of the least characterized disease-associated DNA repeats, and mechanisms causing the repeat expansion in humans have yet to be elucidated. Alternative, non B-DNA structures formed by the expanded repeats are typical in DNA repeat expansion diseases. These sequences may promote instability of the repeat tracts. I determined that slipped strand structure formation occurs for (CCTG)•(CAGG) repeats at a length of 42 or more. In addition, Z-DNA structure forms in the flanking human sequence adjacent to the (CCTG)•(CAGG) repeat tract. I have also performed genetic assays in E. coli cells and results indicate that the (CCTG)•(CAGG) repeats are more similar to the highly unstable (CTG)•(CAG) repeat tracts seen in Huntington's disease and myotonic dystrophy type 1, than to those of the more stable (ATTCT)•(AGAAT) repeat tracts of spinocerebellar ataxia type 10. This instability, however, is RecA-independent in the (CCTG)•(CAGG) and (ATTCT)•(AGAAT) repeats, whereas the instability is RecA-dependent in the (CTG)•(CAG) repeats. Structural studies of the (CCTG)•(CAGG) repeat tract and the flanking sequence, as well as genetic selection assays may reveal the mechanisms responsible for the repeat instability in E. coli, and this may lead to a better understanding of the mechanisms contributing to the human disease state. ^

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Purpose. The purpose of this randomized control repeated measures trial was to determine the effectiveness of a self-management intervention led by community lay workers called promotoras on the health outcomes of Mexican Americans with type 2 diabetes living in a major city on the Texas - Mexico border. The specific aims of this study, in relation to the intervention group participants, were to: (1) decrease the glycosylated hemoglobin (A1c) blood levels at the six-month assessment, (2) increase diabetes knowledge at the three and six-month assessments, and (3) strengthen the participants' beliefs in their ability to manage diabetes at the three and six-month assessments.^ Methods. One hundred and fifty Mexican American participants were recruited at a Catholic faith-based clinic and randomized into an intervention group and a usual-care control group. Personal characteristics, acculturation and baseline A1c, diabetes knowledge and diabetes health beliefs were measured. The six-month, two-phase intervention was culturally specific and it was delivered entirely by promotoras. Phase One of the intervention consisted of sixteen hours of participative group education and bi-weekly telephone contact follow-up. Phase Two consisted of bi-weekly follow-up using inspirational faith-based health behavior change postcards. The A1c levels, diabetes knowledge and diabetes health beliefs were measured at baseline, and three and six months post-baseline. The mean changes between the groups were analyzed using analysis of covariance. ^ Results. The 80% female sample, with a mean age of 58 years, demonstrated very low: acculturation, income, education, health insurance coverage, and strong Catholicism. No significant changes were noted at the three-month assessment, but the mean change of the A1c levels (F (1, 148 = 10.28, p < .001) and the diabetes knowledge scores (F (1, 148 = 9.0, p < .002) of the intervention group improved significantly at six months, adjusting for health insurance coverage. The diabetes health belief scores decreased in both groups.^ Conclusions. This study demonstrated that an intervention led by promotoras could result in decreased A1c levels and increased diabetes knowledge in spite of the very low acculturation, educational level and insurance coverage of the intervention group participants. Clinical implications and recommendations for future research are suggested. ^

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A growing number of studies show strong associations between stress and altered immune function. In vivo studies of chronic and acute stress have demonstrated that cognitive stressors are strongly correlated with high circulating levels of catecholamines (CT) and corticosteroids (CS) that are associated with changes in type-1/type-2 cytokine expression. Although individual pharmacologic doses of CS and CT can inhibit the expression of T-helper 1 (Th1, type-1 like) and promote the production of T-helper 2 (Th2, type-2 like) cytokines in antigen-specific and mitogen stimulated human leukocyte cultures in vitro, little attention has been focused on the effects of combination physiologic-stress doses of CT and CS that may be more physiologically relevant. In addition, both in-vivo and in-vitro studies suggest that the differential expression of the B7 family of costimulatory molecules CD80 and CD86 may promote the expression of type-1 or type-2 cytokines, respectively. Furthermore, corticosteroids can influence the expression of β2-adrenergic receptors in various human tissues. We therefore investigated the combined effects of physiologic-stress doses of in vitro CT and CS upon the type-1/type-2 cytokine balance and expression of B7 costimulatory molecules of human peripheral blood mononuclear cells (PBMC) as a model to study the immunomodulatory effects of physiologic stress. Results demonstrated a significant decrease in type-1 cytokine expression and a significant increase in type-2 cytokine production in our CS+CT incubated cultures when compared to either CT or CS agents alone. In addition, we demonstrated the differential expression of CD80/CD86 in favor of CD86 at the cellular and population level as determined by flow cytometry in lipopolysaccharide stimulated human Monocytes. Furthermore, we developed flow cytometry based assays to detect total β2AR in human CD4+ T-lymphocytes that demonstrated decreased expression of β2AR in mitogen stimulated CD4+ T-lymphocytes in the presence of physiologic stress levels of CS and CT as single in vitro agents, however, when both CS and CT were combined, significantly higher expression of β2AR was observed. In summary, our in vitro data suggest that both CS and CT work cooperatively to shift immunity towards type-2 responses. ^

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Purpose of the study. This study had two components. The first component of the study was the development and implementation of an infrastructure that integrated Promotores who teach diabetes self-management into a community clinic. The second component was a six-month randomized clinical trial (RCT) designed to test the effectiveness of the Promotores in changing knowledge, beliefs, and HbA1c levels among Mexican American patients with type 2 diabetes. ^ Methods. Starfield's adaptation of the Donbedian structure, process, and outcome methodology was used to develop a clinic infrastructure that allowed the integration of Promotores as diabetes educators. The RCT of the culturally sensitive Promotores-led 10-week diabetes self-management program compared the outcomes of 63 patients in the intervention group with 68 patients in a wait-list, usual care control group. Participants were Mexican Americans, at least 18 years of age, with type 2 diabetes, who were patients at a Federally Qualified Health Center on the Texas-Mexico border. At baseline, three months, and six months, data were collected using the Diabetes Knowledge Questionnaire (DKQ, the Health Beliefs Questionnaire (HBQ, and HbA1c levels were drawn by the clinic laboratory. A mixed model methodology was used to analyze the data. ^ Results. The infrastructure to support a Promotores-led diabetes self-management course designed in concert with administration, the physicians, and the CDE, resulted in (1) employment of Promotores to teach diabetes self-management courses; (2) integration of provider and nurse oversight of course design and implementation; (3) management of Promotora training, and the development of teaching competencies and skills; (4) coordination of care through communication and documentation policies and procedures; (5) utilization of quality control mechanisms to maintain patient safety; and (6) promotion of a culturally competent approach to the educational process. The RCT resulted in a significant improvement in the intervention group's DKQ scores over time (F [1, 129] = 4.77, p = 0.0308), and in treatment by time (F [2, 168] = 5.85, p = 0.0035). Neither the HBQ scores nor the HbA1c changed over time. However, the baseline HbA1c was 7.49, almost at the therapeutic level. The DKQ, HBQ, and HbA1c results were significantly affected by age; the DKQ and HbA1c by years with diabetes. ^ Conclusions. The clinic model provides a systematic approach to safely address the educational needs of large numbers of patients with type 2 diabetes who live in communities that suffer from a lack of health care professionals. The Promotores-led diabetes self-management course improved the knowledge of patients with diabetes and may be a culturally sensitive strategy for meeting patient educational needs. The low baseline HbA1c levels in this border community suggested that patients in this Federally Qualified Health Center on the Texas-Mexico border were experiencing good medical management of their diabetes. ^

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Several studies have examined the association between high glycemic index (GI) and glycemic load (GL) diets and the risk for coronary heart disease (CHD). However, most of these studies were conducted primarily on white populations. The primary aim of this study was to examine whether high GI and GL diets are associated with increased risk for developing CHD in whites and African Americans, non-diabetics and diabetics, and within stratifications of body mass index (BMI) and hypertension (HTN). Baseline and 17-year follow-up data from ARIC (Atherosclerosis Risk in Communities) study was used. The study population (13,051) consisted of 74% whites, 26% African Americans, 89% non-diabetics, 11% diabetics, 43% male, 57% female aged 44 to 66 years at baseline. Data from the ARIC food frequency questionnaire at baseline were analyzed to provide GI and GL indices for each subject. Increases of 25 and 30 units for GI and GL respectively were used to describe relationships on incident CHD risk. Adjusted hazard ratios for propensity score with 95% confidence intervals (CI) were used to assess associations. During 17 years of follow-up (1987 to 2004), 1,683 cases of CHD was recorded. Glycemic index was associated with 2.12 fold (95% CI: 1.05, 4.30) increased incident CHD risk for all African Americans and GL was associated with 1.14 fold (95% CI: 1.04, 1.25) increased CHD risk for all whites. In addition, GL was also an important CHD risk factor for white non-diabetics (HR=1.59; 95% CI: 1.33, 1.90). Furthermore, within stratum of BMI 23.0 to 29.9 in non-diabetics, GI was associated with an increased hazard ratio of 11.99 (95% CI: 2.31, 62.18) for CHD in African Americans, and GL was associated with 1.23 fold (1.08, 1.39) increased CHD risk in whites. Body mass index modified the effect of GI and GL on CHD risk in all whites and white non-diabetics. For HTN, both systolic blood pressure and diastolic blood pressure modified the effect on GI and GL on CHD risk in all whites and African Americans, white and African American non-diabetics, and white diabetics. Further studies should examine other factors that could influence the effects of GI and GL on CHD risk, including dietary factors, physical activity, and diet-gene interactions. ^

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This synthesis of the literature provides descriptive analysis and outlines current self-management interventions for African Americans with type 2 diabetes. Specifically, this study describes and explores the design of those studies whose interventions have been shown to lower HbA1C levels in this population by at least 0.5% points, an improvement that provides approximately 10% reduction in long term complications from this disease.^ Results. In total, 37 articles were reviewed and 17 articles met inclusion criteria for analysis. Analysis of each study's methodology and results was performed and selected studies with interventions that resulted in improvements in HbA1C outcomes equal to 0.5% or greater for both group 1 and 2 were summarized by intervention type in table format. Descriptive analysis, outlining the number and characteristics of proximal and distal mediating components addressed in Group 1 studies, was performed in order to determine whether mediating components may have had some relation to effectiveness of intervention on outcome HbA1C. Descriptive analysis revealed that no particular design is substantially more effective than another among Behavioral studies although, there may be an advantage in using culturally sensitive, group interventions that address greater numbers of distal mediating components. Among Process studies, structured approaches (i.e. algorithm care and scheduled follow up), as well as utilization of specialty and group care are represented as effective for African American populations. ^ Conclusions. It may be summarized that by targeting behavior and addressing provider delivery (i.e. algorithm use, group care, home care, and provider follow up) in this population, a greater yield in outcome improvements may be accomplished. However, many gaps exist in a review process that stratifies results and focuses on identifying group specific intervention successes and failures. Further research in different populations will aid researchers and practitioners in discovering the best evidence, and identifying models that could be utilized in practice to achieve the best diabetes management for at risk groups.^

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The type 2 diabetes (diabetes) pandemic is recognized as a threat to tuberculosis (TB) control worldwide. This secondary data analysis project estimated the contribution of diabetes to TB in a binational community on the Texas-Mexico border where both diseases occur. Newly-diagnosed TB patients > 20 years of age were prospectively enrolled at Texas-Mexico border clinics between January 2006 and November 2008. Upon enrollment, information regarding social, demographic, and medical risks for TB was collected at interview, including self-reported diabetes. In addition, self-reported diabetes was supported by blood-confirmation according to guidelines published by the American Diabetes Association (ADA). For this project, data was compared to existing statistics for TB incidence and diabetes prevalence from the corresponding general populations of each study site to estimate the relative and attributable risks of diabetes to TB. In concordance with historical sociodemographic data provided for TB patients with self-reported diabetes, our TB patients with diabetes also lacked the risk factors traditionally associated with TB (alcohol abuse, drug abuse, history of incarceration, and HIV infection); instead, the majority of our TB patients with diabetes were characterized by overweight/obesity, chronic hyperglycemia, and older median age. In addition, diabetes prevalence among our TB patients was significantly higher than in the corresponding general populations. Findings of this study will help accurately characterize TB patients with diabetes, thus aiding in the timely recognition and diagnosis of TB in a population not traditionally viewed as at-risk. We provide epidemiological and biological evidence that diabetes continues to be an increasingly important risk factor for TB.^

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Telemedicine is the use of telecommunications to support health care services and it incorporates a wide range of technology and devices. This systematic review seeks to determine which types of telemedicine technologies have been the most effective at improving the major health factors of subjects with type 2 diabetes. The major health factors identified were blood glucose, systolic and diastolic blood pressure, LDL cholesterol, weight, BMI, triglyceride levels, and waist circumference. A literature search was performed using peer reviewed, scholarly articles focused on the health outcomes of type 2 diabetes patients served by various telemedicine interventions. A total of 15 articles met the search criteria and were then analyzed to determine the significant health outcomes of each telemedicine interventions for type 2 diabetes patients. Results showed that telemedicine interventions using videoconferencing technology resulted in significant improvements in five health factor outcomes (total body weight, BMI, blood glucose, LDL cholesterol, and blood pressure), while telemedicine interventions using web applications and health monitors/modems only produced significant improvements in blood glucose. Future research should focus on examining the costs and benefits of videoconferencing and other telemedicine technologies for type 2 diabetes patients.^

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Vaccination is a management strategy utilized to help reduce prevalence of bovine respiratory disease in feedlots. However, not all animals respond similarly to vaccinations. It is believed that an animal’s genetics control part of the ability to respond to a vaccination protocol. In order to evaluate the genetic control of a new trait such as response to vaccination, it is important to understand the non-genetic factors that affect an animal’s response to vaccination. The objective of this study was to characterize the non-genetic factors affecting overall response to a two-shot vaccination for bovine viral diarrhea virus type 2 (BVDV2) in Angus weanling calves.