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Yonemura Y, Ishibashi H, Fujita T, Liu Y, Wakama S, Sako S, Kitai T, Katayama K, Kamada Y, Taniguchi K, Fujimoto D, Kajiwara J, Hoffman RM. [Pancreatic Acinar Cell Carcinoma with Peritoneal Recurrence Treated with Peritonectomy and Intraoperative Hyperthermic Intraperitoneal Chemotherapy-A Case Report]. Gan To Kagaku Ryoho 2023; 50:1931-1933. [PMID: 38303256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
A 31-year-old man with a big epigastric mass from pancreas body was completely removed by distal pancreatectomy and segmental gastrectomy. Two years after oral administration of S-1 for 4 courses, peritoneal dissemination on the right subdiaphragmatic space was detected. Laparotomy revealed white colored round nodules were found scattered on the peritoneal surface, and the peritoneal cancer index(PCI)was 18. To achieve complete resection of peritoneal nodules, peritonectomy was performed. After complete removal of macroscopic peritoneal metastasis(PM), intraoperative hyperthermic intraoperative peritoneal chemotherapy using 1 gr of gemcitabine and 60 mg of docetaxel was performed for 40 min with thermal dose of 41.5 min. Postoperative course was uneventful. Drug sensitivity test(HDRA method)showed that gemcitabine that gemcitabine showed the highest inhibition rate. The patient was treated with systemic gemcitabine chemotherapy. He is still alive without recurrence 18 months after peritonectomy plus intraoperative HIPEC. Pathological examination showed pancreatic acinar cell carcinoma(PACC)demonstrating positive for chymotrypsin. In conclusion, we present a PACC-case with PM successfully treated by a comprehensive treatment. Intraoperative HIPEC using gemcitabine may be effective for PACC patients with PM in treating residual micrometastasis after peritonectomy.
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Harris MB, Hoffman RM, Olesiak M. Chronic Exercise Mitigates the Effects of Sirtuin Inhibition by Salermide on Endothelium-Dependent Vasodilation. Cardiovasc Toxicol 2021; 21:790-799. [PMID: 34185244 DOI: 10.1007/s12012-021-09669-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 06/08/2021] [Indexed: 11/27/2022]
Abstract
Sirtuins are regulators of eNOS and endothelial function; however, no studies have examined the influence of exercise on sirtuin regulation of endothelial function. Effects of the novel sirtuin inhibitor, salermide, on vascular reactivity in rat aortas were investigated following exercise training of different durations. Male Wistar rats (8-9 months old) were divided into four groups (n = 10-12/group): sedentary (SED), 1 day (1D), 2 weeks (2WK), or 6 weeks (6WK) of exercise. Exercise consisted of running on a motor-driven treadmill at 15 m/min, 15% grade, for 40 min (1D) increased up to 1 h at the end of 2 weeks (2WK) and sustained for an additional 4 weeks (6WK). Dose responses to phenylephrine, sodium nitroprusside, and acetylcholine in the presence or absence of salermide (30 µM) were analyzed. SIRT1 and eNOS protein expression as well as nitrotyrosine levels were determined by immunoblotting. Superoxide dismutase activity was determined by colorimetric assay. Sirtuin inhibition significantly impaired acetylcholine-induced vasorelaxtion in aortas in SED, 1D, and 2WK endurance trained rats but not in 6WK. eNOS expression significantly increased ~ 2.0-fold in 1D, 2WK, and 6WK groups. SIRT1 expression and 3-nitrotyrosine levels were significantly increased in 1D and 2WK but were not significantly elevated in 6WK. SOD levels were significantly elevated in 6WK. These data suggest that chronic endurance training diminishes the role of sirtuins in regulating endothelium-dependent relaxation and appears to be related to changes in SIRT1 expression as well as redox status.
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Levy BT, Hoffman RM, Daly JM, Xu Y, Crockett SD, Shokar NK, Dawson JD, Reuland DS, Zuckerman MJ, Levin AD. Diagnostic Performance of Four Fecal Immunochemical Tests for Detecting Advanced Colorectal Neoplasia: Preliminary Results. Cancer Epidemiol Biomarkers Prev 2019. [DOI: 10.1158/1055-9965.epi-19-0085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Abstract
Screening programs based on fecal blood testing have been shown in randomized controlled trials to reduce colorectal cancer incidence and mortality. Professional organizations highly recommend screening average-risk patients with fecal immunochemical testing (FIT). Many patients find these stool tests more acceptable than colonoscopy and stool testing may be the preferred option for areas with limited endoscopic resources. However, the diagnostic performance of FIT testing, particularly for CLIA-waived point-of-care (POC) tests, has not been well studied. Purpose: We are comparing the diagnostic accuracy of 4 FIT tests, one automated (AUTO) and 3 POC, for detecting advanced neoplasia (advanced adenomas and carcinomas) using colonoscopy as a gold standard. Methods. We are enrolling subjects ages 50 to 85 at 3 academic medical centers in Iowa, Texas, and North Carolina who were scheduled for a screening or surveillance colonoscopy. Each subject completed 4 different FIT tests on a single stool specimen. Based on colonoscopy results, we calculated sensitivity, specificity, and predictive values. We used PROC GLIMMIX models in SAS to compare sensitivity and specificity across the different tests, accounting for the within-patient correlation. Results: We currently have 641 subjects who completed FIT and colonoscopy. Mean age is 61.2 (±7.5) years, 63% women, 63% non-Hispanic white, and 31% Hispanic. We found advanced neoplasia, including 5 carcinomas, in 68 subjects. The sensitivities for detecting these neoplasia were 3%, 22%, 28%, and 16% (AUTO), respectively. Corresponding positive predictive values were 18%, 21%, 33%, and 24% (AUTO). Specificities were 97%, 89%, 90%, and 94% (AUTO), respectively, and corresponding negative predictive values were 89%, 91%, 92%, and 90% (AUTO). We found statistically significant differences in sensitivity (P < 0.01) and specificity (P < 0.01) across tests. Conclusions: Early data suggest that FIT products may vary in their sensitivity and specificity for detecting advanced colorectal neoplasia. This variability could have important impacts on the effectiveness of efforts to limit the burden of colorectal cancer by increasing population-based screening rates through fecal blood testing.
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Hoffman RM, Maskell KF, Cumpston KL. A local survey of gastric lavage for gastrointestinal decontamination in a new century: The future marches on. Am J Emerg Med 2018; 36:1114-1115. [DOI: 10.1016/j.ajem.2017.10.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 10/14/2017] [Indexed: 11/24/2022] Open
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Taylor KL, Luta G, Zotou V, Hoffman RM, Lobo T, Davis KM, Potosky AL, Aaronson D, Van Den ES. Clinical and Psychological Predictors of Switching from Active Surveillance to Active Treatment among Men with Low-Risk Prostate Cancer: the PREPARE Prospective Cohort Study. Cancer Epidemiol Biomarkers Prev 2018. [DOI: 10.1158/1055-9965.epi-18-0064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Abstract
Numerous observational studies have assessed the clinical predictors of switching from active surveillance (AS) to active treatment (AT), but few have assessed psychological and decisional predictors. In a prospective, comparative effectiveness cohort study of men newly diagnosed with low-risk PCa, we assessed whether psychological and decisional factors predicted switching to AT after adjusting for clinical factors. We conducted pre-treatment telephone interviews (N = 1,139; 69.3% participation) with low-risk PCa patients (PSA < 10, Gleason < 7) and a follow-up assessment 6–10 months post-diagnosis (N = 1057; 93%). Clinical variables were obtained from the medical record. The current analysis included men who were on AS for up to 24 months (N = 515), compared to men on AS for >12 months who switched to AT between 12–24 months (N = 86). In Cox proportional hazard models, we included 2 time-dependent covariates measured between diagnosis and 24-months post-diagnosis: PSA (<4, 4–9.99, 10+) and Gleason score (<7, 7+, no surveillance biopsy). Baseline covariates included age (X = 62.3 (SD = 7.0), first degree relative with PCa (25%), number of positive cores (<2 = 75%), urologist initial treatment recommendation (14% AT). Covariates measured at 6 months included prostate- specific anxiety, decisional satisfaction, decisional uncertainty, and preference for shared vs. independent decisions. The fully adjusted model indicated that switching to an active treatment was more likely among those with a PSA > 10 (HR 5.6, 2.4–13.1), Gleason 7+ (HR 20.2, 12.2–33.4), and the urologist's initial recommendation of AT (HR 2.1, 1.04–4.2). The psychological variables, including preference for making independent treatment decisions (HR 2.7, 1.07–6.9) and concern that disease progression will not be detected (HR 1.5, 0.95–2.4), were independently associated with undergoing AT. After adjusting for clinical evidence of disease progression over the first two years post-diagnosis, men's concerns that disease progression will not be detected and preference for making their own treatment decision each independently predicted undergoing AT. These findings suggest the need to provide information and assistance to men who may be uncertain about remaining on AS, particularly when AS remains clinically indicated.
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Yano S, Takehara K, Kishimoto H, Tazawa H, Urata Y, Kagawa S, Bouvet M, Fujiwara T, Hoffman RM. OBP-401-GFP telomerase-dependent adenovirus illuminates and kills high-metastatic more effectively than low-metastatic triple-negative breast cancer in vitro. Cancer Gene Ther 2017; 24:45-47. [PMID: 28106046 DOI: 10.1038/cgt.2016.67] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 10/17/2016] [Accepted: 10/18/2016] [Indexed: 11/09/2022]
Abstract
We previously described the development of a highly-invasive, triple-negative breast cancer (TNBC) variant using serial orthotopic implantation of MDA-MB-231 human breast cancer in nude mice. The isolated variant is highly invasive in the mammary gland and metastasized to lymph nodes in 10 of 12 mice compared with 2 of 12 of the parental cell line. OBP-401 is a telomerase-dependent cancer-specific, green fluorescent protein (GFP)-expressing adenovirus. OBP-401 was used to infect parental MDA-MB-231P cells and high-metastatic MDA-MB-231H and MDA-MB-231HLN isolated from a lymph node metastasis and MDA-MB-231HLM isolated from a lung metastasis. Time-course imaging showed that OBP-401 labeled MDA-MB-231HP, MDA-MB-231HLN, and MDA-MB-231HLM cells more brightly than MDA-MB-231 parental cells. OBP-401 killed MDA-MB-231H, MDA-MB-231HLN, and MDA-MB-231HLM cells more efficiently than MDA-MB-231P parental cells. These results indicate that OBP-401 could infect, label and then kill high-metastatic MDA-MB-231 more efficiently than low-metastatic MDA-MB-231.
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Morgans AK, Fan KH, Koyama T, Albertsen PC, Goodman M, Hamilton AS, Hoffman RM, Stanford JL, Stroup AM, Penson DF. Bone complications among prostate cancer survivors: long-term follow-up from the prostate cancer outcomes study. Prostate Cancer Prostatic Dis 2014; 17:338-42. [PMID: 25134939 PMCID: PMC4227957 DOI: 10.1038/pcan.2014.31] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 06/27/2014] [Accepted: 07/15/2014] [Indexed: 11/08/2022]
Abstract
BACKGROUND To assess the relationship between androgen deprivation therapy (ADT) exposure and self-reported bone complications among men in a population-based cohort of prostate cancer survivors followed for 15 years after diagnosis. METHODS The Prostate Cancer Outcomes Study enrolled 3533 patients diagnosed with prostate cancer between 1994 and 1995. This analysis included participants with non-metastatic disease at the time of diagnosis who completed 15-year follow-up surveys to report development of fracture, and use of bone-related medications. The relationship between ADT duration and bone complications was assessed using multivariable logistic regression models. RESULTS Among 961 surviving men, 157 (16.3%) received prolonged ADT (>1 year), 120 (12.5%) received short-term ADT (⩽ 1 year) and 684 (71.2%) did not receive ADT. Men receiving prolonged ADT had higher odds of fracture (OR 2.5; 95% confidence interval (CI): 1.1-5.7), bone mineral density testing (OR 5.9; 95% CI: 3.0-12) and bone medication use (OR 4.3; 95% CI: 2.3-8.0) than untreated men. Men receiving short-term ADT reported rates of fracture similar to untreated men. Half of men treated with prolonged ADT reported bone medication use. CONCLUSIONS In this population-based cohort study with long-term follow-up, prolonged ADT use was associated with substantial risks of fracture, whereas short-term use was not. This information should be considered when weighing the advantages and disadvantages of ADT in men with prostate cancer.
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Jaganath D, Mulenga C, Hoffman RM, Hamilton J, Boneh G. This is My Story: participatory performance for HIV and AIDS education at the University of Malawi. HEALTH EDUCATION RESEARCH 2014; 29:554-565. [PMID: 24047713 PMCID: PMC4155417 DOI: 10.1093/her/cyt074] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 06/10/2013] [Indexed: 06/02/2023]
Abstract
University students represent a subset of young men and women at risk for HIV in high prevalence settings. Innovative programs are needed to raise awareness on the unique issues around HIV and AIDS in the university campus, while training student leaders for peer-based education. The Process and Collaboration for Empowerment and Discussion (PACED) method engages artists and people living with HIV and AIDS (PLWHA) to create a performance that encourages community dialog about HIV and AIDS and empowers PLWHA. 'This is My Story' was a program at the University of Malawi, Chancellor College, which adapted the PACED approach for university students. A qualitative evaluation conducted 1 year later among students and PLWHA participants and audience members demonstrated retention of the following themes: (i) trust in a relationship and how it affects women,(ii) equality for PLWHA and (iii) life after HIV and AIDS. All of the PLWHA and 90.9% of student participants reported a greater sense of empowerment. Of the audience members, 82.1% discussed the performance with friends and family. We thus present the PACED approach as a valuable tool in HIV and AIDS education and prevention among university students in Malawi.
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Hoffman RM, Olesiak M, Harris MB. Effects of vitamin E supplementation and exercise on endothelial function in rat aortas. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.lb661] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Corcoran TE, Venkataramanan R, Hoffman RM, George MP, Petrov A, Richards T, Zhang S, Choi J, Gao YY, Oakum CD, Cook RO, Donahoe M. Systemic delivery of atropine sulfate by the MicroDose Dry-Powder Inhaler. J Aerosol Med Pulm Drug Deliv 2013; 26:46-55. [PMID: 22691110 PMCID: PMC4227439 DOI: 10.1089/jamp.2011.0948] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Accepted: 03/18/2012] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Inhaled atropine is being developed as a systemic and pulmonary treatment for the extended recovery period after chemical weapons exposure. We performed a pharmacokinetics study comparing inhaled atropine delivery using the MicroDose Therapeutx Dry Powder Inhaler (DPIA) with intramuscular (IM) atropine delivery via auto-injector (AUTO). METHODS The MicroDose DPIA utilizes a novel piezoelectric system to aerosolize drug and excipient from a foil dosing blister. Subjects inhaled a 1.95-mg atropine sulfate dose from the dry powder inhaler on one study day [5 doses × 0.4 mg per dose (nominal) delivered over 12 min] and received a 2-mg IM injection via the AtroPen® auto-injector on another. Pharmacokinetics, pharmacodynamic response, and safety were studied for 12 hr. RESULTS A total of 17 subjects were enrolled. All subjects completed IM dosing. One subject did not perform inhaled delivery due to a skin reaction from the IM dose. Pharmacokinetic results were as follows: area under the curve concentration, DPIA=20.1±5.8, AUTO=23.7±4.9 ng hr/mL (means±SD); maximum concentration reached, DPIA=7.7±3.5, AUTO=11.0±3.8 ng/mL; time to reach maximum concentration, DPIA=0.25±0.47, AUTO=0.19±0.23 hr. Pharmacodynamic results were as follows: maximum increase in heart rate, DPIA=18±12, AUTO=23±13 beats/min; average change in 1-sec forced expiratory volume at 30 min, DPIA=0.16±0.22 L, AUTO=0.11±0.29 L. The relative bioavailability for DPIA was 87% (based on output dose). Two subjects demonstrated allergic responses: one to the first dose (AUTO), which was mild and transient, and one to the second dose (DPIA), which was moderate in severity, required treatment with oral and intravenous (IV) diphenhydramine and IV steroids, and lasted more than 7 days. CONCLUSIONS Dry powder inhalation is a highly bioavailable route for attaining rapid and consistent systemic concentrations of atropine.
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Yano S, Li S, Han Q, Tan Y, Fujiwara T, Hoffman RM. Abstract P4-07-04: Methioninase cell-cycle synchronization potentiates chemotherapy for breast cancer. Cancer Res 2012. [DOI: 10.1158/0008-5472.sabcs12-p4-07-04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Deprivation of methionine selectively arrests cancer cells during late S-phase (Proc. Natl. Acad. Sci. USA 77, 7306–7310, 1980; Biochim. Biophys. Acta, Reviews on Cancer 738, 49–87, 1984), where they are highly sensitive to chemotherapy drugs which damage DNA (J. Natl. Cancer Inst. 76, 629–639, 1986). Cancer cells, transformed to express different color fluorescent reporters during specific phases of the cell cycle (Cell 132, 487–498, 2008), were used to monitor the onset of the S/G2-phase block due to methionine deprivation effected by recombinant methioninase (rMETase). The S/G2-phase blocked cancer cells fluoresced yellow or green in contrast to cancer cells in G1 which fluoresced red. Cancer cells, including MCF-7 breast cancer, synchronously blocked in S/G2-phase by rMETase, were identified by their yellow-green fluorescence and allowed to accumulate to the maximum extent. At the point of maximum yellow/green cells in the culture, the cells were administered chemotherapy drugs which interact with DNA or block DNA synthesis such as doxorubicin. We termed this procedure color-coded chemotherapy (CCC). CCC was highly effective against the cancer cells (90% cell kill). In contrast, treatment of cancer cells with drugs only, and without rMETase-effected S/G2-phase synchrony, led to the majority of the cancer cell population being blocked in G1 phase (red fluorescent) where they were resistant to the drugs (40% cell kill). CCC, which identifies, by fluorescent color, when cancer cells are blocked in S/G2-phase by a unique cell-cycle-blocking agent, rMETase, demonstrates the potential of cell-synchronization-based chemotherapy for breast cancer.
Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-07-04.
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Hoffman RM, Olesiak M, Harris MB. Effects of Exercise Training Duration on SIRT1 and eNOS Expression in Rat Aortas. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.853.17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Suetsugu A, Digman M, Gratton E, Moriwaki H, Saji S, Bouvet M, Hoffman RM. P5-02-05: Real-Time Subcellular Imaging of Breast Cancer Cell Attachment in Blood Vessels Using GFP-Labeled Paxillin in Live Mice. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-p5-02-05] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Paxillin is involved in the assembly of focal adhesions. We wish to visualize paxillin behavior in breast cancer cells in vivo, as well as in vitro.
Materials and Methods: Dual-photon confocal microscopy was used to image paxillin behavior by linking it to GFP. MDA-MB-231 human breast cancer cells expressing paxillin-GFP were imaged in vitro and in vivo adhering and trafficking in blood vessels in mice. 106 paxillin-GFP expressing breast cancer cells were injected in the epigastric cranialis vein.
Results: In vitro, round breast cancer cells had greater paxillin movement than stretched cancer cells as seen by fluorescence imaging. Paxillin-GFP breast cancer cells in the epigastric cranialis vein were initially rounded and had GFP-expressing protrusions. At later timepoints, many paxillin-GFP-expressing breast cancer cells stretched. The breast cancer cells then extravasated and subsequently grew around the outer surface of the blood vessel after one week. Two weeks after injection, paxillin-GFP expressing breast cancer cells were imaged migrating along the vessel wall. Most of the paxillin-GFP expressing breast cancer cells were stretched and were not mobile. With anti-VEGF treatment, paxillin was observed in round structures within the cells rather than stretched structures and paxillin movement within the cell was arrested.
Discussion: These results demonstrate that breast cancer cells brightly expressing paxillin-GFP and two-photon confocal microscopy can allow the visualization of the behavior of paxillin within breast cancer cells during adhesion and migration along the walls of blood vessels, as well as during anti-angiogenesis therapy.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-02-05.
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Olesiak M, Hoffman RM, Harris MB. Effects of the sirtuin inhibitor, salermide, on exercise‐induced changes in endothelial function. FASEB J 2011. [DOI: 10.1096/fasebj.25.1_supplement.1108.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Staniar WB, Kronfeld DS, Hoffman RM, Wilson JA, Harris PA. Weight prediction from linear measures of growing Thoroughbreds. Equine Vet J 2010; 36:149-54. [PMID: 15038438 DOI: 10.2746/0425164044868585] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
REASON FOR PERFORMING STUDY Monitoring weight of foals is a useful management practice to aid in maximising athletic potential while minimising risks associated with deviations from normal growth. OBJECTIVE To develop predictive equations for weight, based on linear measurements of growing Thoroughbreds (TBs). METHODS Morphometric equations predicting weight from measurements of the trunk and legs were developed from data of 153 foals. The accuracy, precision and bias of the best fitting equation were compared to published equations using a naive data set of 22 foals. RESULTS Accuracy and precision were maximised with a broken line relating calculated volumes (V(t + l)) to measured weights. Use of the broken line is a 2 step process. V(t + l) is calculated from linear measures (m) of girth (G), carpus circumference (C), and length of body (B) and left forelimb (F). V(t + I) = ([G2 x B] + 4[C2 x F]) 4pi. If V(t + l) < 0.27 m3, weight is estimated: Weight (kg) = V(t + l) x 1093. If V(t + l) > or = 0.27 m3: Weight (kg) = V(t + l) x 984 + 24. The broken line was more accurate and precise than 3 published equations predicting the weight of young TBs. CONCLUSIONS Estimation of weight using morphometric equations requires attention to temporal changes in body shape and density; hence, a broken line is needed. Including calculated leg volume in the broken line model is another contributing factor to improvement in predictive capability. POTENTIAL RELEVANCE The broken line maximises its value to equine professionals through its accuracy, precision and convenience.
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Kimura H, Zhang L, Zhao M, Hayashi K, Tsuchiya H, Tomita K, Bouvet M, Wessels J, Hoffman RM. Targeted therapy of spinal cord glioma with a genetically modified Salmonella typhimurium. Cell Prolif 2009; 43:41-8. [PMID: 19922490 DOI: 10.1111/j.1365-2184.2009.00652.x] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
OBJECTIVE Spinal cord tumours are highly malignant and often lead to paralysis and death due to their infiltrative nature, high recurrence rate and limited treatment options. In this study, we measured antitumour efficacy of the Salmonella typhimurium A1-R tumour-targeting bacterium strain, administered systemically or intrathecally, to spinal cord cancer in orthotopic mouse models. MATERIALS AND METHODS Tumour fragments of U87-RFP were implanted by surgical orthotopic implantation into the dorsal site of the spinal cord. Five and 10 days after transplantation, eight mice in each group were treated with A1-R (2 x 10(7) CFU/200 microL i.v. injection or 2 x 10(6) CFU/10 microL intrathecal injection). RESULTS Untreated mice showed progressive paralysis beginning at day 6 after tumour transplantation and developed complete paralysis between 18 and 25 days. Mice treated i.v. with A1-R had onset of paralysis at approximately 11 days and at 30 days; five mice developed complete paralysis, while the other three mice had partial paralysis. Mice treated by intrathecal injection of A1-R had onset of paralysis at approximately 18 days and one mouse was still not paralysed at day 30. Only one mouse developed complete paralysis at day 30 in this group. Intrathecally treated animals had a significantly better survival than the i.v. treated group as well as over the control group. CONCLUSIONS These results suggest that S. typhimurium A1-R monotherapy can effectively treat spinal cord glioma.
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Bouvet M, Hoffman RM. Clinically-relevent orthotopic metastatic models of pancreatic cancer imageable with fluorescent genetic reporters. MINERVA CHIR 2009; 64:521-539. [PMID: 19859041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This article describes authors' cumulative experience with the development and preclinical application of clinically-relevant, metastatic orthotopic mouse models of pancreatic cancer made imageable with genetic reporters. These models utilize the human pancreatic cancer cell lines which have been genetically engineered to selectively express high levels of green fluorescent protein (GFP) or red fluorescent protein (RFP). Tumors with fluorescent genetic reporters are established subcutaneously in nude mice, and fragments of the subcutaneous tumors are then surgically transplanted onto the pancreas. Loco-regional tumor growth and distant metastasis of these orthotopic implants occurs spontaneously and rapidly throughout the abdo-men in a manner consistent with clinical human disease. Highly specific, high-resolution, real-time quantitative fluorescence imaging of tumor growth and metastasis may be achieved in vivo without the need for contrast agents, invasive techniques, or expensive imaging equipment. A high correlation between florescence optical imaging, magnetic resonance imaging, and ultrasound in these models has been demonstrated. Transplantation of RFP-expressing tumor fragments onto the pancreas of GFP- or cyan fluorescent protein-expressing transgenic mice was used to facilitate visualization of tumor-host interaction between the pancreatic cancer cells and host-derived stroma and vasculature. Such in vivo models have enabled visualization in real time and acquisition of images of the progression of pancreatic cancer in the live animal, the models also demonstrate the real-time antitumor and antimetastatic effects of several novel therapeutic strategies on pancreatic malignancy. These fluorescent models are therefore powerful and reliable tools with which to investigate metastatic human pancreatic cancer and novel therapeutic strategies directed against it.
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Hayashi K, Yamauchi K, Yamamoto N, Tsuchiya H, Tomita K, Bouvet M, Wessels J, Hoffman RM. A color-coded orthotopic nude-mouse treatment model of brain-metastatic paralyzing spinal cord cancer that induces angiogenesis and neurogenesis. Cell Prolif 2009; 42:75-82. [PMID: 19143765 DOI: 10.1111/j.1365-2184.2008.00574.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVE Cancer of the spinal cord is highly malignant and often leads to paralysis and death. A realistic mouse model would be an important benefit for the better understanding and treatment of spinal cord glioma. MATERIALS AND METHODS To develop an imageable, patient-like model of this disease, U87 human glioma tumour fragments (expressing red fluorescent protein), were transplanted by surgical orthotopic implantation into the spinal cord of nontransgenic nude mice or transgenic nude mice expressing nestin-driven green fluorescent protein (ND-GFP). In ND-GFP mice, GFP is expressed in nascent blood vessels and neural stem cells. The animals were treated with temozolomide or vehicle control. RESULTS The intramedullary spinal cord tumour grew at the primary site, caused hind-limb paralysis and also metastasized to the brain. Temozolomide inhibited tumour growth (P<0.01) and prevented metastasis, as well as prevented paralysis in four mice and delayed paralysis in two mice of the six tested (P=0.005). In the ND-GFP-expressing host, ND-GFP cells staining positively for neuronal class III-beta-tubulin or CD31, surrounded the tumour. These results suggest that the tumour stimulated both neurogenesis and angiogenesis, respectively. CONCLUSION A patient-like model of spinal cord glioma was thus developed, which can be used for the discovery of new agents, including those that inhibit invasion and metastasis of the disease as well as those that prevent paralysis.
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Othman MO, Bradley AG, Choudhary A, Hoffman RM, Roy PK. Variable stiffness colonoscope versus regular adult colonoscope: meta-analysis of randomized controlled trials. Endoscopy 2009; 41:17-24. [PMID: 19160154 DOI: 10.1055/s-0028-1103488] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND AND STUDY AIMS The variable stiffness colonoscope (VSC) may have theoretical advantages over standard adult colonoscopes (SACs), though data are conflicting. We conducted a meta-analysis to compare the efficacies of the VSC and SAC. STUDY DESIGN We searched Medline (1966 - 2008) and abstracts of gastroenterology scientific meetings in the 5 years to February 2008, only for randomized clinical trials (RCTs) of adult patients. Trial quality was assessed using the Delphi list. In a meta-analysis with a fixed effects model, cecal intubation rates, cecal intubation times, abdominal pain scores, sedation used, and use of ancillary maneuvers, were compared in separate analyses, using weighted mean differences (WMDs), standardized mean differences (SMDs), or odds ratios (ORs). RESULTS Seven RCTs satisfied the inclusion criteria (1923 patients), four comparing VSC with SAC procedures in adults, and three evaluating the pediatric VSC. There was no significant heterogeneity among the studies. The overall trial quality was adequate. Cecal intubation rate was higher with the use of VSC (OR = 2.08, 95 % confidence interval [CI] 1.29 to 3.36). The VSC was associated with lower abdominal pain scores and a decreased need for sedation during colonoscopy. Cecal intubation time was similar for the two colonscope types (WMD = - 0.21 minutes, 95 % CI - 0.85 to 0.43). Because of the nature of the intervention no studies were blinded. There was no universal method for using the VSC. CONCLUSIONS Compared with the SAC, VSC use was associated with a higher cecal intubation rate, less abdominal pain, and decreased need for sedation. However, cecal intubation times were similar for the two colonoscope types.
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Seitz G, Warmann SW, Fuchs J, Heitmann H, Mahrt J, Busse AC, Ruck P, Hoffman RM, Wessels JT. Imaging of cell trafficking and metastases of paediatric rhabdomyosarcoma. Cell Prolif 2008; 41:365-74. [PMID: 18336479 PMCID: PMC6495802 DOI: 10.1111/j.1365-2184.2008.00520.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2007] [Accepted: 09/16/2007] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVE The aim of this study was to establish a preclinical mouse model to study metastases of paediatric rhabdomyosarcoma at the macroscopic and cellular levels, with different imaging methods. EXPERIMENTAL DESIGN The alveolar rhabdomyosarcoma cell line Rh30 was stably transfected with the red fluorescent protein (DsRed2) then was xenotransplanted (intravenous injection [n = 8], and footpad injection [n = 8]) into nude mice (NMRI nu/nu). Macroscopic imaging of metastases was performed using DsRed2-fluorescence and flat-panel volumetric computed tomography scan. In a further series of animals (n = 8), in vivo cell trafficking of rhabdomyosarcoma cells using cellular imaging with an Olympus OV100 variable-magnification small-animal imaging system was used. RESULTS Metastases in the pelvis, thoracic wall and skin were visualized by fluorescence imaging. Pelvic metastases were found after tail vein injection and at other metastatic sites after footpad injection. Flat-panel volumetric computed tomography scan data allowed highly specific analysis of contrast between tumour and surrounding tissue. Correlation between fluorescence and flat-panel volumetric computed tomography scan imaging data was observed. Single-cell imaging visualized tumour cells in the vessels and demonstrated the arrest of tumour cells at vessel junctions followed by extravasation of the tumour cells. CONCLUSION We established a model for visualization of experimental metastatic invasion and describe relevant tools for imaging childhood rhabdomyosarcoma metastases at the macroscopic and cellular levels. Imaging of cell trafficking visualized the behaviour of tumour cells and development of metastases by accumulation and extravasation of rhabdomyosarcoma cells.
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Hoffman RM, Monga M, Elliot SP, Macdonald R, Wilt TJ. Microwave thermotherapy for benign prostatic hyperplasia. Cochrane Database Syst Rev 2007:CD004135. [PMID: 17943811 DOI: 10.1002/14651858.cd004135.pub2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Transurethral resection of the prostate (TURP) has been the gold-standard treatment for alleviating urinary symptoms and improving urinary flow in men with symptomatic benign prostatic hyperplasia (BPH). However, the morbidity of TURP approaches 20%, and less invasive techniques have been developed for treating BPH. Preliminary data suggest that microwave thermotherapy, which delivers microwave energy to produce coagulation necrosis in prostatic tissue, is a safe, effective treatment for BPH. OBJECTIVES To assess the therapeutic efficacy and safety of microwave thermotherapy techniques for treating men with symptomatic benign prostatic obstruction. SEARCH STRATEGY Randomized controlled trials were identified from the Cochrane Collaboration Library, MEDLINE, EMBASE, bibliographies of retrieved articles and reviews, and by contacting expert relevant trialists and microwave manufacturers. SELECTION CRITERIA All randomized controlled trials evaluating transurethral microwave thermotherapy (TUMT) for men with symptomatic BPH were eligible for this review. Comparison groups could include transurethral resection of the prostate, minimally invasive prostatectomy techniques, sham thermotherapy procedures, and medications. Outcome measures included urinary symptoms, urinary function, prostate volume, mortality, morbidity, and retreatment. Two reviewers independently identified potentially relevant abstracts and then assessed the full papers for inclusion. DATA COLLECTION AND ANALYSIS Two reviewers independently abstracted study design, baseline characteristics and outcomes data and assessed methodological quality using a standard form. We attempted to obtain missing data from authors and/or sponsors. MAIN RESULTS Fourteen studies involving 1493 patients met inclusion criteria, including six comparisons of microwave thermotherapy with TURP, seven comparisons with sham thermotherapy procedures, and one comparison with an alpha blocker. Study durations ranged from 3 to 60 months. The mean age of subjects was 66.8 years, and the baseline symptom scores and urinary flow rates, which did not differ across treatment groups, demonstrated moderately severe lower urinary tract symptoms. The pooled mean urinary symptom scores decreased by 65% with TUMT and by 77% with TURP. The weighted mean difference (WMD) (95% confidence interval) for the symptom score was -1.36 (-2.25 to -0.46), favoring TURP. The pooled mean peak urinary flow increased by 70% with TUMT and by 119% with TURP. The WMD for peak urinary flow was 5.08 (3.88 to 6.28) mL/s, favoring TURP. Compared to TURP, TUMT was associated with decreased risks for retrograde ejaculation, treatment for strictures, hematuria, blood transfusions, and the transurethral resection syndrome, but increased risks for dysuria, urinary retention, and retreatment for BPH symptoms. Microwave thermotherapy improved symptom scores (IPSS WMD -4.75, 95% CI -3.89 to -5.60) and peak urinary flow (WMD 1.67 mL/s, 95% CI 0.99 to 2.34) compared with sham procedures. Microwave thermotherapy also improved symptom scores (IPSS WMD -4.20, 95% CI -3.15 to -5.25) and peak urinary flow (WMD 2.30 mL/s, 95% CI 1.47 to 3.13) in the one comparison with alpha blockers. No studies evaluated the effects of symptom duration, patient characteristics, prostate-specific antigen levels, or prostate volume on treatment response. AUTHORS' CONCLUSIONS Microwave thermotherapy techniques are effective alternatives to TURP and alpha-blockers for treating symptomatic BPH for men with no history of urinary retention or previous prostate procedures and prostate volumes between 30 to 100 mL. However, TURP provided greater symptom score and urinary flow improvements and reduced the need for subsequent BPH treatments compared to TUMT. Small sample sizes and differences in study design limit comparison between devices with different designs and energy levels. The effects of symptom duration, patient characteristics, or prostate volume on treatment response are unknown.
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Bobek V, Boubelik M, Fiserová A, L'uptovcová M, Vannucci L, Kacprzak G, Kolodzej J, Majewski AM, Hoffman RM. Anticoagulant drugs increase natural killer cell activity in lung cancer. Lung Cancer 2005; 47:215-23. [PMID: 15639720 DOI: 10.1016/j.lungcan.2004.06.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2004] [Revised: 06/02/2004] [Accepted: 06/16/2004] [Indexed: 10/26/2022]
Abstract
BACKGROUND In preclinical studies in animal models and in initial clinical trials, anticoagulation drugs have been shown to be effective in the prevention and treatment of haematogenous metastasis, and in the prolongation of survival in animal models. However, only a few studies have been performed on the direct influence of anticoagulation drugs on the immune system. OBJECTIVE The purpose of this study is to determine the effect of warfarin, unfractioned heparin, low molecular weight heparins (LMWHs), and acetylsalicylic acid anticoagulants on the functional activity of natural killer (NK) cells. PATIENTS AND METHOD Cytotoxic activity in patients with early, operable stages of non-small-cell lung cancer was compared with healthy volunteers. Cytotoxic studies were also carried out in tumor-bearing animals. RESULTS Lung-cancer patients were characterized by significantly lower NK cell cytotoxicity (7.07 +/- 3.15) than healthy donors (44.12 +/- 10.62, P < 0.001). NK cell activation was found in both in vitro experiments using peripheral blood mononuclear cells (PBMC) from healthy donors and ex vivo in lung carcinoma patients after treatment with unfractionated heparin and fraxiparine. Similarly, potentiation of NK cell activity in Lewis lung carcinoma-bearing mice was found after therapy with unfractionated heparin. NK cell activity is lower in lung cancer patients than in normal subjects. CONCLUSIONS NK cell activation was increased by LMWHs. Other anticoagulants augment the effector function of NK cells in cancer patients and in an animal model of lung cancer. This is a novel effect of these compounds, which were thought previously to exert their effect only via their anticoagulant properties.
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Burton DW, Geller J, Yang M, Jiang P, Barken I, Hastings RH, Hoffman RM, Deftos LJ. Monitoring of skeletal progression of prostate cancer by GFP imaging, X-ray, and serum OPG and PTHrP. Prostate 2005; 62:275-81. [PMID: 15389781 DOI: 10.1002/pros.20146] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND Prostate cancers (PCas) produce factors that can serve as biomarkers for tumor metastasis and bone progression. Transduced GFP expression by cancer cells can be imaged to monitor therapy. We exploited both concepts by developing a GFP-expressing PCa cell line that expresses PTHrP and studying it in an animal model of malignancy with methods that assess the skeletal progression of this tumor. METHODS We developed a GFP-producing PCa cell line by stable transduction of PC-3 PCa cells. This PC-3 variant was used to study tumor progression in an immunocompromised mouse model. Skeletal progression of the PCa cells and the effects of pamidronate administration were evaluated radiologically, fluorometrically, and by measurement of serum tumor markers. RESULTS The PC-3 cells produced extensive bone lesions when injected into the tibia of immunocompromised mice. The skeletal progression of the PC-3 cells could be monitored by GFP optical imaging, X-ray, and by measurements of tumor products in serum, notably PTHrP and OPG. Pamidronate treatment reduced tumor burden as assessed at autopsy by imaging and biomarkers. CONCLUSIONS Pamidronate treatment exhibited anti-tumor effects that were reflected by decreases in serum PTHrP, OPG, and by GFP and radiological imaging procedures. Imaging of GFP expression enables real-time monitoring of tumor growth in the bone. PTHrP and OPG may be useful as tumor biomarkers for PCa that has metastasized to bone. This novel human PCa model can be used to study the clinical potential of diagnostic and therapeutic modalities in the skeletal progression of PCas.
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Williams CA, Kronfeldt DS, Hess TM, Saker KE, Waldron JN, Crandell KM, Hoffman RM, Harris PA. Antioxidant supplementation and subsequent oxidative stress of horses during an 80-km endurance race1. J Anim Sci 2004; 82:588-94. [PMID: 14974559 DOI: 10.2527/2004.822588x] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
This study tested the development of oxidative stress and the effects of antioxidant supplementation in an 80-km ride. A precompetition survey revealed that no competitor would participate without vitamin E supplementation; therefore, 46 horses were paired for past performances and randomly assigned to two groups of 23 each for 3 wk of supplementation before the ride. One group (E) was orally supplemented with 5,000 IU of vitamin E per day; the other group (E+C) received that dose of vitamin E plus 7 g/d of vitamin C. Blood samples, temperature, and heart rate were taken the day before the race, at 21 and 56 km during the ride, at completion, and after 20 min of recovery. Plasma was assayed for lipid hydroperoxides, alpha-tocopherol, total ascorbate, albumin, creatine kinase (CK), and aspartate aminotransferase (AST). Total glutathione and glutathione peroxidase activity were determined in red blood cells and white blood cells. Thirty-four horses completed the race, 12 horses (six in E and six in E+C) did not finish for reasons including lameness, metabolic problems, and rider option. Plasma ascorbate was higher (P = 0.045) in the E+C group than in the E group. Other than ascorbate, neither antioxidant status nor CK and AST activities were affected by supplementation with E+C vs. E. Red blood cell glutathione peroxidase, white blood cell total glutathione, lipid hydroperoxides, CK, and AST increased, and red blood cell total glutathione and white blood cell glutathione peroxidase activity decreased with distance (P < 0.001). Positive correlations were found for plasma lipid hydroperoxides on CK (r = 0.25; P = 0.001) and AST (r = 0.33; P < 0.001). These results establish an association between muscle leakage and a cumulative index of oxidative stress.
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Hoffman RM, Boston RC, Stefanovski D, Kronfeld DS, Harris PA. Obesity and diet affect glucose dynamics and insulin sensitivity in Thoroughbred geldings. J Anim Sci 2003; 81:2333-42. [PMID: 12968709 DOI: 10.2527/2003.8192333x] [Citation(s) in RCA: 205] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Insulin resistance is considered a risk factor in obesity, laminitis, exertional rhabdomyolysis, and osteochondrosis. The objective was to use the minimal model to estimate glucose effectiveness (Sg) and insulin sensitivity (Si) in nonobese to obese horses initially adapted to forage only, then adapted to forage plus supplements rich in starch and sugar (SS) or fiber and fat (FF). Ten Thoroughbred geldings, with BCS of 5 (nonobese), 6 (moderately obese), and 7 to 8 (obese), were adapted to pasture and hay, allocated to two groups, and fed SS or FF in a switch-back design with 8 wk of adaptation. Modified frequent-sampling i.v. glucose tolerance tests were applied after adaptation to forage, SS, and FF. For the tolerance tests, horses were kept in stalls overnight and provided hay, and venous catheters were placed the next morning. Baseline samples were collected, 0.3 g of glucose/kg of BW was given i.v., and blood was sampled at 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, and 19 min. At 20 min, 30 mU of insulin/kg of BW was given, followed by sampling at 22, 23, 24, 25, 27, 30, 35, 40, 50, 60, 70, 80, 90, 100, 120, 150, and 180 min. Plasma was analyzed for glucose and insulin, and Si, Sg, acute insulin response to glucose, and the disposition index were calculated. Normality was tested using the Shapiro-Wilk statistic. Body condition effects were analyzed using a mixed model with repeated measures. Diet effects were analyzed using a Wilcoxon signed rank test. The Sg was higher in obese than nonobese (P = 0.003) and moderately obese (P = 0.007) horses; Si was lower in obese than nonobese (P = 0.008) horses, and acute insulin response to glucose was higher in obese than nonobese (P = 0.039) horses. Effects of diet were likely confounded by body condition, but horses had lower Si (P = 0.066) when fed SS compared with FF, especially when nonobese. In conclusion, the minimal model effectively estimated Sg, Si, acute insulin response to glucose, and disposition index in horses. Obese geldings were insulin-resistant and seemed to rely primarily on Sg for glucose disposal. Feeding a diet rich in sugar and starch decreased insulin sensitivity of horses. Maintenance of body condition and avoidance of grain-based meals rich in sugar and starch would be beneficial to decrease the risk of developing insulin resistance and associated metabolic syndromes in horses, especially for horses at risk for these syndromes.
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