http://hdl.handle.net/10027/7300 Wed, 22 May 2013 20:09:12 GMT 2013-05-22T20:09:12Z http://hdl.handle.net/10027/8605 Hematological and acute-phase responses to diet-induced obesity in IL-6 KO mice Pini, Maria; Rhodes, Davina H.; Fantuzzi, Giamila Obesity is associated with chronic inflammation and elevated levels of IL-6. The role of IL-6 in induction of acute-phase proteins and modulation of haematological responses has been demonstrated in models of inflammation and aging, but not in obesity. We hypothesized that IL-6 is necessary to regulate the acute-phase response and hematological changes associated with diet-induced obesity (DIO) in mice. Feeding a 60% kcal/fat diet for 13 weeks to C57BL6 WT male mice induced a significant increase in IL-6 expression in visceral adipose tissue (VAT), but not liver, compared to mice fed chow diet. Significantly elevated IL-6 levels were present in the peritoneal lavage fluid, but not plasma, of DIO compared to lean mice. A comparable degree of obesity, hepatomegaly, hyperleptinemia, VAT inflammation and insulin resistance was observed in DIO WT and IL-6 KO mice compared to WT and KO mice fed chow diet. Significant leukocytosis was observed in DIO WT but not DIO KO mice compared to lean groups. A significant reduction in platelet counts, without alterations in platelet size, percentage of circulating reticulated platelets and number of bone marrow megakaryocytes, was present in DIO KO mice compared to each other group. Hepatic expression of thrombopoietin was comparable in each group, with DIO WT and KO mice having reduced VAT expression compared to lean mice. Lean KO mice had significantly elevated plasma levels of thrombopoietin compared to each other group, whereas liver-associated thrombopoietin levels were comparable in each group. Deficiency of IL-6 resulted in blunted hepatic induction of the acute-phase protein serum amyloid A-1, whereas expression of hepcidin-1 and -2, LPS-binding protein, ceruloplasmin, plasminogen activator inhibitor-1 and thrombospondin-1 was IL-6- independent. In conclusion, in the absence of overt metabolic alterations, IL-6 modulates leukocytosis,thrombopoiesis induction of SAA-1, but not other acute-phase proteins in obese mice. NOTICE: this is the author’s version of a work that was accepted for publication in Cytokine. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Cytokine, Vol 56, Issue 3, (December 2011). doi.org/10.1016/j.cyto.2011.09.015 Thu, 01 Dec 2011 06:00:00 GMT http://hdl.handle.net/10027/8605 2011-12-01T06:00:00Z http://hdl.handle.net/10027/8587 Fear of Falling Does Not Alter the Kinematics of Recovery from an Induced Trip: A Preliminary Study Marone, Jane R.; Rosenblatt, Noah J.; Troy, Karen L.; Grabiner, Mark D. Objective: To provide preliminary information about the relationships between self-reported fear of falling (FOF) in healthy community-dwelling women, the number of falls, and recovery kinematics in response to a laboratory-induced trip. Design: Cohort study Setting: Clinical research laboratory Participants: A subset of community dwelling older women (N=33) recruited from studies of laboratory induced trips and fall-prevention. Intervention: A laboratory-induced trip. Main Outcome Measures: The number of fallers in the FOF vs. the control group. Recovery kinematics of FOF falls vs. control group falls, and FOF recoveries vs. control group recoveries were compared. The degree of FOF was assessed by Activities Balance Confidence Scale(ABC). Results: Falls occurred in 6/14 (43%) of the FOF and 4/16 (25%) of control subjects (p=0.26). Kinematics of FOF falls were similar to those of control falls. At the completion of the initialrecovery step, FOF showed significantly greater trunk extension velocity than controls (-82.1±- 66.1 vs. -25.0±-53.0 degrees/sec respectively; p=0.05). All other variables were not significantly different. ABC scores of FOF subjects did not differ significantly between fallers and those who recovered (mean=75.2±5.6, 71.1±11.8, respectively; p=0.84). Conclusion: Healthy community-dwelling older adults would benefit from fall prevention, regardless of the presence of self-reported FOF. NOTICE: this is the author’s version of a work that was accepted for publication in Archives of Physical Medicine and Rehabilitation . Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Archives of Physical Medicine and Rehabilitation , Vol 92, Issue 12, (December 2011). DOI: 10.1016/j.apmr.2011.06.034 Thu, 01 Dec 2011 06:00:00 GMT http://hdl.handle.net/10027/8587 2011-12-01T06:00:00Z http://hdl.handle.net/10027/8545 On the Filtering of Intersegmental Loads During Running Edwards, W. Brent; Troy, Karen L; Derrick, Timothy R. When performing inverse dynamics analysis, smoothing kinematic and force platform data at different cutoff frequencies creates an “impact” like artifact that is visible in the joint moments during impulsive activity. Here we illustrate a processing technique in which inverse dynamics analysis is performed on the raw kinematic and force platform data and the joint reaction forces and moments are subsequently smoothed based on the frequency content of the distal reaction force. The effectiveness of this technique is illustrated on forward dynamics simulation data with known intersegmental loads. We then apply the technique to an experimental data set of 10 subjects running at three prescribed speeds. We show that performing inverse dynamics on the raw data and subsequently smoothing the intersegmental loads results in minimal attenuation of the joint reaction force and avoids impact artifacts in the joint moments. Artifacts that occur using a traditional filtering technique are systematic, become more pronounced with speed, and are most noticeable at the hip joint. NOTICE: this is the author’s version of a work that was accepted for publication in Gait and Posture . Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in ON THE FILTERING OF INTERSEGMENTAL LOADS DURING RUNNING, Vol 34, Issue 3, (JUL 2011) DOI: 10.1016/j.gaitpost.2011.06.006 Fri, 01 Jul 2011 05:00:00 GMT http://hdl.handle.net/10027/8545 2011-07-01T05:00:00Z http://hdl.handle.net/10027/8543 Improvements in LDL particle size and distribution by short-term alternate day modified fasting in obese adults Varady, Krista A.; Bhutani, Surabhi; Klempel, Monica C.; Lamarche, Benoît Alternate day modified fasting (ADMF) beneficially modulates several indicators of CHD risk, but its effects on LDL particle size have never been tested. Accordingly, we examined the effects of ADMF on LDL particle size and distribution in obese adults. Sixteen obese subjects participated in a 10-week trial with three consecutive phases: (1) 2-week control phase; (2) 4-week ADMF controlled feeding phase; (3) 4-week ADMF self-selected feeding phase. After 8 weeks of diet, body weight and waist circumference were reduced (P,0·05) by 5·6 (SEM 0·9) kg and 4·0 (SEM 0·9) cm, respectively. LDL-cholesterol and TAG concentrations decreased (P,0·05) by 25 (SEM 10)% and 32 (SEM 6)%, respectively. Peak LDL particle size increased (P,0·05) from 266 (SEM 1) to 268 (SEM 1)Ȧ. Additionally, the proportion of small LDL particles decreased (P,0·05) from 13 (SEM 2)% to 9 (SEM 3)%, while the proportion of large LDL particles increased (P,0·05) from 68 (SEM 4)% to 76 (SEM 4)% post-treatment. These findings suggest that ADMF is an effective diet strategy for increasing LDL particle size and decreasing the proportion of small, dense LDL particles in obese adults. © Varady e.t al. 2010. The original version is available through Cambridge University Press at DOI: 10.1017/S0007114510003788 Tue, 01 Feb 2011 06:00:00 GMT http://hdl.handle.net/10027/8543 2011-02-01T06:00:00Z