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There is clinical evidence that patient‐specific comorbidities like osteoporosis, concomitant tissue injury, and ischemia may strongly interfere with bone regeneration. However, underlying mechanisms are still unclear. To study these mechanisms in detail, appropriate animal models are needed. For decades, bone healing has been studied in large animals, including dogs, rabbits, pigs, or sheep. However, large animal models display a limited ability to study molecular pathways and cellular functions. Therefore in recent years, mice and rats have become increasingly popular as a model organism for fracture healing research due to the availability of molecular analysis tools and transgenic models. Both large and small animals can be used to study comorbidities and risk factors, modelling the human clinical situation. However, attention has to be paid when choosing an appropriate model due to species differences between large animals, rodents, and humans. This review focuses on large and small animal models for the common comorbidities ischemic injury/reduced vascularization, osteoporosis, and polytrauma, and critically discusses the translational and molecular aspects of these models. Here, we review material which was presented at the workshop "Animal Models of Comorbidities in Fracture Healing Research" at the 2019 ORS Annual Meeting in Austin Texas. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2491–2498, 2019 [ABSTRACT FROM AUTHOR]

Background: Growing evidence suggests that dairy consumption is associated with lower type 2 diabetes risk. However, observational studies have reported inconsistent results, and few have examined dairy's association with the underlying disorders of insulin resistance and β-cell dysfunction. Objective: We investigated the association of the dairy fatty acid biomarkers pentadecanoic acid (15:0) and trans-palmitoleic acid (trans 16:1n-7) with type 2 diabetes traits by evaluating 1) prospective associations with incident diabetes after 5 y of follow-up and 2) cross-sectional associations with directly measured insulin resistance and β-cell dysfunction. Design: The study analyzed 659 adults without diabetes at baseline from the triethnic multicenter Insulin Resistance Atherosclerosis Study (IRAS). Diabetes status was assessed by using oral-glucose-tolerance tests. Frequently sampled intravenous-glucose-tolerance tests measured insulin sensitivity (SI) and β-cell function [disposition index (DI)]. Serum fatty acids were quantified by using gas chromatography. Logistic and linear regression models were adjusted for demographic, lifestyle, and dietary variables. Results: Serum 15:0 was a significant biomarker for total dairy intake in the IRAS cohort. It was associated with a decreased incident diabetes risk (OR: 0.73, P = 0.02) and was positively associated with log SI (β: 0.84, P = 0.03) and log DI (β: 2.21, P = 0.02) in fully adjusted models. trans 16:1n-7 was a marker of total partially hydrogenated dietary fat intake and was not associated with outcomes in fully adjusted models. Conclusions: Serum 15:0, a marker of short-term intake of this fatty acid, was inversely associated with diabetes risk in this multiethnic cohort. This study may contribute to future recommendations regarding the benefits of dairy products on type 2 diabetes risk. [ABSTRACT FROM AUTHOR]

Although hypercholesterolemia has been recognized as a risk factor for coronary heart disease (CHD) for decades, only in recent years have clinical trials definitively shown the efficacy of lowering serum cholesterol to prevent the occurrence or worsening of CHD. In 1985, an NIH consensus conference published guidelines for the diagnosis and treatment of hypercholesterolemia. Prior to 1985, physicians and lay people alike were not yet convinced of the necessity to know one's cholesterol level, nor did they know what levels should be treated. In a community-based survey of cardiovascular risk factors, known as the San Antonio Heart Study, in which 1,932 Mexican-Americans (MAs) and 1,133 non-Hispanic whites (NHWs) were examined between 1979 and 1985, the authors found that only 36/501 MAs (7%) and 54/312 NHWs (17%) in the moderate- or high-risk categories were aware that their cholesterols were high. Of the total number aware, including those whose cholesterol levels were in the low-risk range, only 23/97 MAs (24%) and 29/108 NHWs (27%) were receiving dietary or drug treatment. Of those being treated, only 9/23 MAs (39%) and 12/29 NHWs (41%) were effectively controlled. Mexican-Americans were less likely to be aware of their hypercholesterolemia than non-Hispanic whites, but both ethnic groups had low levels of treatment. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this article is to extend our previous studies of persistent organic pollutant (POP) contamination of U.S. food by measuring perfluorinated compounds (PFCs), organochlorine pesticides, and polychlorinated biphenyls (PCBs) in composite food samples. This study is part of a larger study reported in two articles, the other of which reports levels of polybrominated diphenyl ethers and hexabromocyclododecane brominated flame retardants in these composite foods [Schecter et al. 2010. Polybrominated diphenyl ethers (PBDEs) and hexabromocyclodecane (HBCD) in composite U.S. food samples, Environ Health Perspect 118:357-362]. Methods: In this study we measured concentrations of 32 organochlorine pesticides, 7 PCBs, and 11 PFCs in composite samples of 31 different types of food (310 individual food samples) purchased from supermarkets in Dallas, Texas (USA), in 2009. Dietary intake of these chemicals was calculated for an average American. Results: Contamination varied greatly among chemical and food types. The highest level of pesticide contamination was from the dichlorodiphenyltrichloroethane (DDT) metabolite p,p'-dichlorodiphenyldichloroethylene, which ranged from 0.028 ng/g wet weight (ww) in whole milk yogurt to 2.3 ng/g ww in catfish fillets. We found PCB congeners (28, 52, 101, 118, 138, 153, and 180) primarily in fish, with highest levels in salmon (PCB-153, 1.2 ng/g ww; PCB-138, 0.93 ng/g ww). For PFCs, we detected perfluorooctanoic acid (PFOA) in 17 of 31 samples, ranging from 0.07 ng/g in potatoes to 1.80 ng/g in olive oil. In terms of dietary intake, DDT and DDT metabolites, endosulfans, aldrin, PCBs, and PFOA were consumed at the highest levels. Conclusion: Despite product bans, we found POPs in U.S. food, and mixtures of these chemicals are consumed by the American public at varying levels. This suggests the need to expand testing of food for chemical contaminants. [ABSTRACT FROM AUTHOR]

BackgroundPrehypertension increases mortality risk. Pulse pressure is also associated with increased mortality. Nevertheless, the impact of pulse pressure on the relationship between prehypertension and mortality is not known in individuals who are free of diabetes and cardiovascular disease.MethodsCox regression analysis was used to examine mortality risk among 3,632 (97.0%) participants in the San Antonio Heart Study (age range, 25–64 years; mean follow-up, 15.2 years). Results were adjusted for age, sex, ethnicity, education, body mass index (BMI), smoking, and total cholesterol concentration. The Seventh Report of the Joint Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) categories were used for blood pressure staging: normal, <120/80 mm Hg; prehypertension, 120–139/80–89 mm Hg.ResultsPrehypertension prevalence was 31.6% at baseline. There were 218 deaths during the follow-up period. Prehypertension-predicted mortality (all-cause, hazard ratio (HR) 1.49 (1.12–1.99); cardiovascular, HR 1.79 (1.07–3.02)). Relative to normal blood pressure plus pulse pressure in the lower tertile, prehypertension plus pulse pressure in the upper tertile was associated with increased mortality (all-cause, HR 2.14 (1.38–3.32); cardiovascular, HR 2.47 (1.13–5.39)); however, prehypertension plus pulse pressure in the lower tertile was not significantly associated with mortality (all-cause, HR 1.19 (0.52–2.67); cardiovascular, HR 0.43 (0.05–3.40)).ConclusionsPrehypertension increases mortality risk (all-cause and cardiovascular) in individuals who are free of diabetes and cardiovascular disease. Nevertheless, this relationship is not evident in individuals with narrow pulse pressure. Therefore, pulse pressure may be a relevant measure of blood pressure for the definition of normal blood pressure.American Journal of Hypertension 2009; doi:10.1038/ajh.2009.151 [ABSTRACT FROM AUTHOR]

The article presents the results of a study on which obesity index can explain the prevalence differences in patients with type 2 diabetes in Mexico, Spain and Texas. Body mass index (BMI) is higher among Mexican-American men while waist circumference was higher among men in San, Antonio, Texas. Height correlated with age in men and women in Mexico City and Spain. The area under the receiver operating characteristic curve (AUC) for BMI was smaller than any other indices.

OBJECTIVE — To examine the influence of obesity and prevention of weight gain on the incidence of type 2 diabetes. RESEARCH DESIGN AND METHODS — We examined participants in the San Antonio Heart Study, a prospective population-based study of Mexican Americans and non-Hispanic whites residing in San Antonio, Texas. BMI was stratified into four categories: normal (<25 kg/m²), overweight (≥25 kg/m² and <30 kg/m²), obese (≥30 kg/m² and <35 kg/m²), and very obese (≥35 kg/m²). The number and proportion of incident cases prevented by targeting each BMI category were estimated. In addition, we calculated the decrease in risk of developing type 2 diabetes associated with weight gain prevention across both the BMI and age spectra. RESULTS — Preventing normal individuals from becoming overweight would result in the greatest reduction in incidence of type 2 diabetes. This would result in a 62 and 74% reduction in the incidence of type 2 diabetes in Mexican Americans and non-Hispanic whites, respectively. Preventing the entire population from gaining, on average, 1 BMI unit would result in a reduction in incidence of type 2 diabetes of 12.4 and 13.0% in Mexican Americans and non-Hispanic whites, respectively. CONCLUSIONS — The majority of cases of type 2 diabetes were in individuals who were overweight or mildly obese with a family history of type 2 diabetes. Public health resources should be directed toward the prevention of weight gain among normal and overweight individuals in order to prevent the maximum number of cases of type 2 diabetes. [ABSTRACT FROM AUTHOR]

Background: The standard method of identifying persons at high risk for type 2 diabetes mellitus involves detection of impaired glucose tolerance, which requires a costly and inconvenient 2-hour oral glucose tolerance test. Because clinical trials have indicated that diabetes is preventable by using behavioral or pharmacologic interventions, less expensive methods of identifying high-risk persons are needed. Objective: To determine whether multivariable models are superior to glucose tolerance tests for identifying persons at high risk for diabetes mellitus. Design: Prospective cohort study. Setting: San Antonio, Texas. Participants: 1791 Mexican Americans and 1112 non-Hispanic whites without diabetes at baseline who were randomly selected from census tracts. Measurements: Medical history; body mass index; blood pressure; fasting and 2-hour plasma glucose levels; fasting serum total, low-density lipoprotein, and high-density lipoprotein cholesterol levels; and triglyceride level. Results: For prediction of 7.5-year incidence of type 2 diabetes, the area under the receiver-operating characteristic (ROC) curve for a multivariable model involving readily available clinical variables was significantly (P < 0.001) greater than the area under the ROC curve for the 2-hour glucose value alone (84.3% vs. 77.5%). Impaired glucose tolerance represents a single point on the latter curve. Adding the 2-hour glucose measurement to the multivariable model increased the area under its ROC curve, but only from 84.3% to 85.7%. Conclusion: Persons at high risk for diabetes mellitus are better identified by using a simple prediction model than by relying exclusively on the results of a 2-hour oral glucose tolerance test. Although adding the 2-hour glucose variable to the model enhanced prediction, the resulting slight improvement entails greater cost and inconvenience. [ABSTRACT FROM AUTHOR]

Studies the prevalence and incidence of hypertension and diabetes among Mexican Americans in San Antonio, Texas. Comparison with non-Hispanic whites; Sex differences; Comparison with the prevalence of hypertension and diabetes in Mexico City, Mexico.

Although type II diabetes is associated with both microvascular and macrovascular complications, duration of diabetes and severity of glycemia are strongly associated only with the former. Since prediabetic individuals are hyperinsulinemia, and since hyperinsulinemia may be a cardiovascular risk factor, we hypothesized that prediabetic individuals might have an atherogenic pattern of risk factors even before the onset of clinical diabetes, thereby explaining the relative lack of an association of macrovascular complications with either glycemic severity or disease duration. We documented the cardiovascular risk factor status of 614 initially nondiabetic Mexican Americans who later participated in an 8-year follow-up of the San Antonio Heart Study, a population-based study of diabetes and cardiovascular disease. Individuals who were nondiabetic at the time of baseline examination, but who subsequently developed type II diabetes (ie, confirmed prediabetic subjects, n = 43), had higher levels of total and low-density lipoprotein cholesterol, triglyceride, fasting glucose and insulin, 2-hour glucose, body mass index, and blood pressure, and lower levels of high-density lipoprotein cholesterol than subjects who remained nondiabetic (n = 571). Most of these differences persisted after adjustment for obesity and/or level of glycemia, but were abolished after adjustment for fasting insulin concentration. When subjects with impaired glucose tolerance at baseline (n = 106) were eliminated, the more atherogenic pattern of cardiovascular risk factors was still evident (and statistically significant) among initially normoglycemic prediabetic subjects. These results indicate that prediabetic subjects have an atherogenic pattern of risk factors (possibly caused by obesity, hyperglycemia, and especially hyperinsulinemia), which may be present for many years and may contribute to the risk of macrovascular disease as much as the duration of clinical diabetes itself. [ABSTRACT FROM AUTHOR]

Cardiovascular disease is the leading cause of morbidity, disability, and death among patients with type II (non-insulin-dependent) diabetes mellitus. Moreover, hyperlipidemia is also common among these patients. Despite this, there are virtually no data regarding the level of awareness and treatment of hyperlipidemia among diabetic subjects at the community level. We therefore examined 374 Mexican-Americans and 86 non-Hispanic whites with type II diabetes identified in an epidemiologic survey that involved 3279 Mexican-Americans and 1847 non-Hispanic whites who resided in San Antonio, Tex. More than 40% of the diabetic subjects were hyperlipidemic according to the criteria of the National Cholesterol Education Program, and an additional 23% had hypertriglyceridemia and/or low levels of high-density lipoprotein cholesterol. By contrast, less than one fourth of the nondiabetic subjects were hyperlipidemic. Only approximately 25% of non-Hispanic whites with diabetes were aware of their hyperlipidemia, and less than 10% were receiving treatment. Awareness and treatment were even less frequent among Mexican-Americans with diabetes. Community physicians should be encouraged to give early attention to the management of lipid disorders in their diabetic patients. [ABSTRACT FROM AUTHOR]

The article presents a study on the possible exposure of U.S. professional airline workers to polybrominated diphenyl ethers (PBDEs). It notes that PBDEs are brominated flame retardants which are used in the manufacture of foam used in sofas, chairs and mattresses. It offers an analysis on the relationship between the total PBDE blood levels and the hours worked in an airplane.

The article reviews the article "Perfluorinated Compounds, Polychlorinated Biphenyls and Organochlorine Pesticide Contamination in Composite Food Samples From Dallas, Texas, USA," by A. Schechter, J. Colacino, D. Haffner and et al, which appeared in the periodical "Alternative Medicine Review" in 2010.

Purpose: To examine the mortality risk associated with diabetes in the Mexico City Diabetes Study (MCDS) and the San Antonio Heart Study (SAHS). Methods: Prospective cohorts conducted 1990–2007 in MCDS and 1979–2000 in SAHS. Mortality risk was examined using Cox proportional hazard models in 1402 non-Hispanic whites (NHW), 1907 U.S.-born Mexican-Americans (MA), 444 Mexican-born MA, and 2281 Mexico City residents (MCR) between the ages of 35–64. Results: Age- and sex-adjusted mortality hazard ratios (HR) comparing U.S.-born MA, Mexican-born MA, and MCR to NHW were 1.09 (95% confidence interval [CI]: 0.86, 1.37), 1.23 (95% CI: 0.86, 1.76), and 0.97 (95% CI: 0.77, 1.23), respectively, in nondiabetic individuals; in contrast, mortality risk varied in diabetic individuals with respective HRs of 1.77 (95% CI: 1.20, 2.61), 1.08 (95% CI: 0.59, 1.97), and 2.27 (95% CI: 1.53, 3.35) (interaction p = .0003). Excluding Mexican-born MA and nondiabetic individuals, controlling for medication use, insulin use, fasting glucose levels, and duration of diabetes explained a significant proportion of the mortality differential (HRs relative to NHW were 1.31 [95% CI: 0.87, 1.98] in U.S.-born MA and 1.38 [95% CI: 0.89, 2.12] in MCR). Conclusions: This study provides evidence that diabetes is more lethal in U.S.-born MA and MCR than in NHW. [Copyright &y& Elsevier]

Abstract: Objectives: The objectives of this study were to provide updated measurements of PBDEs in US food, to estimate possible difference in levels from differing geographical regions, and to provide an improved estimate of current dietary intake. Methods: Thirty matched food samples for a total of 90 samples were collected from each of three cities (Los Angeles, California; Dallas, Texas; and Albany, New York) and were analyzed for 13 polybrominated diphenyl ether congeners (BDE 28, 47, 49, 66, 85, 99, 100, 138, 153, 154, 183, 203, and 209). Dietary intake of PBDEs was estimated by food type, age, and sex. Results: In this pilot study, we did not note a statistically significant difference in total PBDE levels in food collected from the three locations. The median total PBDE levels (estimating non-detected values as half of the detection limit) in meat, dairy, eggs, and fish were 267 pg/g wet weight (ww) (range 102–3156 pg/g ww), 176 pg/g ww (range 41–954 pg/g ww), 637 pg/g ww (range 193–932 pg/g ww), and 243 pg/g ww (range 36–2161 pg/g ww). PBDE intake from food was estimated to range from 2.7 ng/kg/day for children 2 through 5 years of age to 0.8 ng/kg/day for women aged 60 years and older. This compares closely with our previous study where the intake estimate was 2.7 ng/kg/day for children 2 through 5 years of age and 0.9 ng/kg/day for women aged 60 years and older. Conclusion: We did not find a decrease of PBDEs in food since our previous studies which we expected to find due to the declining use of PBDEs in the USA. These findings could be consistent with food contamination from depot sources of PBDEs. A larger, more representative sampling of the US food supply is indicated based on our findings. [Copyright &y& Elsevier]