Knee osteoarthritis remains a tremendous public health concern, both in terms of health-related quality of life and financial burden of disease. Translational research is a critical step towards understanding and mitigating the long-term effects of this disease process. Animal models provide practical and clinically relevant ways to study both the natural history and response to treatment of knee osteoarthritis. Many factors including size, cost, and method of inducing osteoarthritis are important considerations for choosing an appropriate animal model. Smaller animals are useful because of their ease of use and cost, while larger animals are advantageous because of their anatomical similarity to humans. This evidence-based review will compare and contrast several different animal models for knee osteoarthritis. Our goal is to inform the clinician about current research models, in order to facilitate the transfer of knowledge from the “bench” to the “bedside.”

Although several epidemiologic studies have shown that ;-glutamyltransferase (GGT) is independently associated with cardiovascular disease and all-cause mortality, its relationship with cancer incidence remains widely unexplored. In several experimental models, the ability of cellular GGT to modulate crucial redox-sensitive functions has been established, and it thus may play a role in tumor progression, as has been repeatedly suggested. We prospectively investigated the association between GGT and risk of overall and site-specific cancer incidence in a large population-based cohort of 79,279 healthy Austrian men with serial GGT measurements. Median follow-up was 12.5 years. Adjusted Cox proportional hazards models were calculated to evaluate GGT as an independent predictor for cancer incidence, and nonparametric regression splines were fitted to flexibly capture the dose-response relationship. Elevated GGT significantly increased overall cancer risk, showing a clear dose-response relationship (P for GGT log-unit increase < 0.0001; P for trend < 0.0001). In comparison with the reference GGT concentration (25 units/L), we found adjusted relative risks (95% confidence intervals) equalling 1.19 (1.15-1.22) for GGT concentrations of 60 units/L, 1.32 (1.28-1.36) for 100 units/L, 1.67 (1.60-1.75) for 200 units/L, and 2.30 (2.14-2.47) for 400 units/L. In cancer site-specific models, GGT was significantly associated with malignant neoplasms of digestive organs, the respiratory system/intrathoracic organs, and urinary organs (all P < 0.0001). Age of participants significantly modified the association of GGT and cancer risk (P < 0.001), revealing markedly stronger associations in participants ages V65 years. Our findings, for the first time, show that elevated GGT is significantly associated with increased cancer risk in men. [Cancer Res 2008;68(10):3970-7]

Alterations of the mycobiota composition associated with Crohn’s disease (CD) are challenging to link to defining elements of pathophysiology, such as poor injury repair. Using culture-dependent and -independent methods, we discovered that Debaryomyces hansenii preferentially localized to and was abundant within incompletely healed intestinal wounds of mice and inflamed mucosal tissues of CD human subjects. D. hansenii cultures from injured mice and inflamed CD tissues impaired colonic healing when introduced into injured conventionally raised or gnotobiotic mice. We reisolated D. hansenii from injured areas of these mice, fulfilling Koch’s postulates. Mechanistically, D. hansenii impaired mucosal healing through the myeloid cell–specific type 1 interferon–CCL5 axis. Taken together, we have identified a fungus that inhabits inflamed CD tissue and can lead to dysregulated mucosal healing.

Although several epidemiologic studies have shown that gammaglutamyltransferase (GGT) is associated with cardiovascular disease and all-cause mortality, its relationship with cancer incidence remains widely unexplored. In experimental models the ability of cellular GGT to modulate crucial redox-sensitive functions has been established, and it may thus play a role in tumor progression. In the present study, we investigated the association of GGT with overall and site-specific cancer incidence in a population-based cohort of 92,843 Austrian women with 349,674 serial GGT measurements, prospectively followed-up for a median of 13.5 years. The relationship between GGT and cancer incidence was analyzed using adjusted Cox regression models with age as underlying time metric with age as underlying time metric including GGT concentrations at baseline and incorporating repeated GGT measurements as a time-dependent variable. During follow-up, 4,884 incidence cancers were observed. Compared to normal low GGT (<17.99 U/L), cancer risk was elevated for all other GGT categories (p for trend < 0.0001), with adjusted hazard ratios (95% confidence intervals) of 1.06 (0.99-1.13) for GGT levels between 18.00 and 35.99 U/L (normal high), 1.12 (1.02-1.22) for GGT levels between 36.00 and 71.99 U/L (elevated) and 1.43 (1.28-1.61) for highly elevated GGT (>72.00 U/L). Very similar results were seen when GGT was analyzed as a time-dependent variable. In cancer-site specific models, elevated GGT statistically significantly increased the risk for malignant neoplasms of digestive organs, the respiratory system/intrathoracic organs, breast and female genital organs and lymphoid and haematopoietic cancers (all, p < 0.006). Our study is the first to demonstrate in a large population-based cohort that high GGT levels significantly increased cancer risk in women.Published 2008 Wiley-Liss, Inc. This article is a US Government work, and, as such, is in the public domain in the United States of America.Key words: gamma-glutamyltransferase; cancer incidence; risk factor; epidemiology; women Gamma-glutamyltransferase (GGT), present on the external surface of most cells and in serum, is the enzyme responsible for the extracellular catabolism of glutathione (GSH), the main thiol antioxidant in mammalian cells. 1,2 In clinical practice, GGT is commonly used as a diagnostic test to assess liver dysfunction, and as a biological marker of excessive alcohol intake. 1,3,4 However, several recent epidemiologic studies have shown elevated GGT to independently influence morbidity and mortality from causes other than liver disease. Particularly, GGT was independently related to cardiovascular disease, 5-12 it correlated with most cardiovascular risk factors [13][14][15][16] and, more recently, an association with chronic kidney disease was found. 17 In addition, several large-scale studies indicate an independent role of GGT for premature death from all causes. 9,18,19 The association of GGT with cancer incidence, however, remains largely unexplored. Several ex...

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