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618 citation(s) found for "O'Brien, J F".

Age, Obesity, and Sex Effects on Insulin Sensitivity and Skeletal Muscle Mitochondrial Function
Karakelides, Helen, Irving, Brian A. , Short, Kevin R. , O’Brien, Peter C. , Nair, K. Sreekumaran

Diabetes | October 16, 2009 | Volume: 59 | Issue: 1 | Pages: 89-97

10.2337/db09-0591 | PMID 19833885 Get It

OBJECTIVE Reductions in insulin sensitivity in conjunction with muscle mitochondrial dysfunction have been reported to occur in many conditions including aging. The objective was to determine whether insulin resistance and mitochondrial dysfunction are directly related to chronological age or are related to age-related changes in body composition. RESEARCH DESIGN AND METHODS Twelve young lean, 12 young obese, 12 elderly lean, and 12 elderly obese sedentary adults were studied. Insulin sensitivity was measured by a hyperinsulinemic-euglycemic clamp, and skeletal muscle mitochondrial ATP production rates (MAPRs) were measured in freshly isolated mitochondria obtained from vastus lateralis biopsy samples using the luciferase reaction. RESULTS Obese participants, independent of age, had reduced insulin sensitivity based on lower rates of glucose infusion during a hyperinsulinemic-euglycemic clamp. In contrast, age had no independent effect on insulin sensitivity. However, the elderly participants had lower muscle MAPRs than the young participants, independent of obesity. Elderly participants also had higher levels inflammatory cytokines and total adiponectin. In addition, higher muscle MAPRs were also noted in men than in women, whereas glucose infusion rates were higher in women. CONCLUSIONS The results demonstrate that age-related reductions in insulin sensitivity are likely due to an age-related increase in adiposity rather than a consequence of advanced chronological age. The results also indicate that an age-related decrease in muscle mitochondrial function is neither related to adiposity nor insulin sensitivity. Of interest, a higher mitochondrial ATP production capacity was noted in the men, whereas the women were more insulin sensitive, demonstrating further dissociation between insulin sensitivity and muscle mitochondrial function.
Clinical Practice Guideline: Hoarseness (Dysphonia)
Schwartz, Seth, Cohen, Seth M. , Dailey, Seth H. , Deutsch, Ellen S. , Gillespie, M. Boyd , Granieri, Evelyn, Hapner, Edie R. , Kimball, C. Eve, Krouse, Helene J. , McMurray, J. Scott , Medina, Safdar, O’Brien, Karen , Ouellette, Daniel R. , Messinger‐Rapport, Barbara J. , Stachler, Robert J., Strode, Steven W., Thompson, Dana M. , Stemple, Joseph C., Willging, J. Paul, Cowley, Terrie , McCoy, Scott, Bernad, Peter G., Patel, Milesh M., Rosenfeld, Richard M. , Kimball, CC, Cohen, Seth M

Otolaryngology–Head and Neck Surgery | September 2, 2009 | Volume: 141 | Issue: S1 | Pages: 1-31

10.1016/j.otohns.2009.06.744 | PMID 19729111 Get It

Objective:This guideline provides evidence‐based recommendations on managing hoarseness (dysphonia), defined as a disorder characterized by altered vocal quality, pitch, loudness, or vocal effort that impairs communication or reduces voice‐related quality of life (QOL). Hoarseness affects nearly one‐third of the population at some point in their lives. This guideline applies to all age groups evaluated in a setting where hoarseness would be identified or managed. It is intended for all clinicians who are likely to diagnose and manage patients with hoarseness.Purpose:The primary purpose of this guideline is to improve diagnostic accuracy for hoarseness (dysphonia), reduce inappropriate antibiotic use, reduce inappropriate steroid use, reduce inappropriate use of anti‐reflux medications, reduce inappropriate use of radiographic imaging, and promote appropriate use of laryngoscopy, voice therapy, and surgery. In creating this guideline the American Academy of Otolaryngology—Head and Neck Surgery Foundation selected a panel representing the fields of neurology, speech‐language pathology, professional voice teaching, family medicine, pulmonology, geriatric medicine, nursing, internal medicine, otolaryngology–head and neck surgery, pediatrics, and consumers.ResultsThe panel made strong recommendations that 1) the clinician should not routinely prescribe antibiotics to treat hoarseness and 2) the clinician should advocate voice therapy for patients diagnosed with hoarseness that reduces voice‐related QOL. The panel made recommendations that 1) the clinician should diagnose hoarseness (dysphonia) in a patient with altered voice quality, pitch, loudness, or vocal effort that impairs communication or reduces voice‐related QOL; 2) the clinician should assess the patient with hoarseness by history and/or physical examination for factors that modify management, such as one or more of the following: recent surgical procedures involving the neck or affecting the recurrent laryngeal nerve, recent endotracheal intubation, radiation treatment to the neck, a history of tobacco abuse, and occupation as a singer or vocal performer; 3) the clinician should visualize the patient's larynx, or refer the patient to a clinician who can visualize the larynx, when hoarseness fails to resolve by a maximum of three months after onset, or irrespective of duration if a serious underlying cause is suspected; 4) the clinician should not obtain computed tomography or magnetic resonance imaging of the patient with a primary complaint of hoarseness prior to visualizing the larynx; 5) the clinician should not prescribe anti‐reflux medications for patients with hoarseness without signs or symptoms of gastroesophageal reflux disease; 6) the clinician should not routinely prescribe oral corticosteroids to treat hoarseness; 7) the clinician should visualize the larynx before prescribing voice therapy and document/communicate the results to the speech‐language pathologist; and 8) the clinician should prescribe, or refer the patient to a clinician who can prescribe, botulinum toxin injections for the treatment of hoarseness caused by adductor spasmodic dysphonia. The panel offered as options that 1) the clinician may perform laryngoscopy at any time in a patient with hoarseness, or may refer the patient to a clinician who can visualize the larynx; 2) the clinician may prescribe anti‐reflux medication for patients with hoarseness and signs of chronic laryngitis; and 3) the clinician may educate/counsel patients with hoarseness about control/preventive measures.Disclaimer:This clinical practice guideline is not intended as a sole source of guidance in managing hoarseness (dysphonia). Rather, it is designed to assist clinicians by providing an evidence‐based framework for decision‐making strategies. The guideline is not intended to replace clinical judgment or establish a protocol for all individuals with this condition, and may not provide the only appropriate approach to diagnosing and managing this problem.
Fatty Acid Metabolism in the Elderly: Effects of Dehydroepiandrosterone and Testosterone Replacement in Hormonally Deficient Men and Women
Koutsari, Christina , Ali, Asem H. , Rizza, Robert A., O’Brien, Peter C. , Khosla, Sundeep , Jensen, Michael D. , Nair, K. Sreekumaran , Khosla, Sundeep

The Journal of Clinical Endocrinology & Metabolism | July 1, 2009 | Volume: 94 | Issue: 9 | Pages: 3414-3423

10.1210/jc.2009-0165 | PMID 19567532 Get It

Context: Aging, low dehydroepiandrosterone (DHEA), and testosterone are associated with increased adiposity and metabolic risk. Treatment with these hormones may improve these abnormalities. Objective: The objective of the study was to determine effects of aging, DHEA, or testosterone replacement on adiposity, meal fat partitioning, and postabsorptive lipolysis. Design: This was a cross-sectional, 2-yr, double-blind, randomized, placebo-controlled trial. Setting: The study was conducted in the general community. Patients: Elderly women and men (≥60 yr) with low DHEA sulfate (women and men) and bioavailable testosterone (men) concentrations and young adults. Interventions: Thirty elderly women each received 50 mg DHEA or placebo daily for 2 yr. Thirty elderly men received 75 mg DHEA, 29 received 5 mg testosterone (patch), and 32 received placebo daily for 2 yr. Thirty young women and 32 young men served as controls. Main Outcome Measures: In vivo measures of meal fat storage into sc fat, postabsorptive lipolysis, and regional adiposity at baseline and after treatment. Results: At baseline, the elderly had more body fat, greater systemic lipolysis (women, P = 0.0003; men, P < 0.0001) adjusted for resting energy expenditure, greater meal fat oxidation (women, P = 0.026; men, P = 0.0025), and less meal fat storage in sc fat (women, P = 0.0139; men, P= 0.0006). Although testosterone treatment increased meal fat storage into upper- vs. lower-body fat in elderly men, neither hormone affected regional adiposity, meal fat oxidation, or systemic lipolysis. Conclusions: Aging, in the context of low DHEA sulfate (women and men) and bioavailable testosterone (men) concentrations, is associated with changes in meal fat partitioning and postabsorptive lipolysis that are not corrected by DHEA and only partly corrected by testosterone replacement. DHEA or testosterone treatment of hormone-deficient elderly does not normalize adipose tissue lipolysis, but testosterone restores a “youthful” meal fat storage pattern in elderly men.
The Effect of Vitamin D2 and Vitamin D3 on Intestinal Calcium Absorption in Nigerian Children with Rickets
Thacher, Tom D. , Obadofin, Michael O, Abrams, Steven A. , O'Brien, Kimberly O , Thacher, Thomas D

The Journal of Clinical Endocrinology & Metabolism | July 1, 2009 | Volume: 94 | Issue: 9 | Pages: 3314-3321

10.1210/jc.2009-0018 | PMID 19567516 Get It

De novo deletion 17p13.1 chronic lymphocytic leukemia shows significant clinical heterogeneity: the M. D. Anderson and Mayo Clinic experience
Tam, Constantine S. , Abruzzo, Lynne V. , Dyke, Daniel L. Van , Lynn, Alice, Keating, Michael J. , Shanafelt, Tait D. , Wierda, William G. , O’Brien, Susan , Ferrajoli, Alessandra , Lerner, Susan A. , Kay, Neil E. , Tam, Constantine S

Blood | May 4, 2009 | Volume: 114 | Issue: 5 | Pages: 957-964

10.1182/blood-2009-03-210591 | PMID 19414856 Get It

To determine the clinical fate of patients with de novo deletion 17p13.1 (17p−) chronic lymphocytic leukemia (CLL), we retrospectively studied the outcome of 99 treatment-naive 17p− CLL patients from the M. D. Anderson Cancer Center (n = 64) and the Mayo Clinic (n = 35). Among 67 asymptomatic patients followed for progression, 53% developed CLL requiring treatment over 3 years. Patients who had not progressed by 18 months subsequently had stable disease, with 3 of 19 patients progressing after follow-up of up to 70 months. Risk factors for progressive disease were Rai stage of 1 or higher and unmutated immunoglobulin variable region heavy chain (IgVH). The overall survival rate was 65% at 3 years. Rai stage 1 or higher, unmutated IgVH, and 17p− in 25% or more of nuclei were adverse factors for survival. The 3-year survival rates of patients with 1 or fewer, 2, and 3 of these factors were 95%, 74%, and 22%, respectively (P < .001). Response rates to therapy with rituximab (n = 6); purine analogues and rituximab (n = 25); and purine analogues, rituximab, and alemtuzumab (n = 16) combinations were 50%, 72%, and 81%, respectively. Patients with 17p− CLL exhibit clinical heterogeneity, with some patients experiencing an indolent course. Survival can be predicted using clinical and biologic characteristics.
Neurotrophic Factor–Expressing Mesenchymal Stem Cells Survive Transplantation into the Contused Spinal Cord Without Differentiating into Neural Cells
Rooney, Gemma E., McMahon, Siobhán S. , Ritter, Thomas , Moran, Cathal J., Madigan, Nicolas N. , Flügel, Alexander , Dockery, Peter , O’Brien, Timothy , Howard, Linda , Windebank, Anthony J. , Barry, Frank , García, Yolanda García

Tissue Engineering Part A | March 31, 2009 | Volume: 15 | Issue: 10 | Pages: 3049-3059

10.1089/ten.tea.2009.0045 | PMID 19335061 Get It

Higher muscle protein synthesis in women than men across the lifespan, and failure of androgen administration to amend age‐related decrements
Ford, G. C., Klaus, Katherine A. , Basu, Rita , Rizza, Robert A., Khosla, Sundeep , O’Brien, Peter C. , Henderson, Gregory C. , Dhatariya, Ketan , Jensen, Michael Dam , Nair, K. Sreekumaran , Khosla, Sundeep

The FASEB Journal | September 30, 2008 | Volume: 23 | Issue: 2 | Pages: 631-641

10.1096/fj.08-117200 | PMID 18827019 Get It

We investigated age and sex effects and determined whether androgen replacement in elderly individuals (≥60 yr) could augment protein synthesis. Thirty young men and 32 young women (18‐31 yr) were studied once, whereas 87 elderly men were studied before and after 1 yr of treatment with 5 mg/day testosterone (T), 75 mg/day dehydroepiandrosterone (DHEA), or placebo (P);and 57 elderly women were studied before and after 1 yr of treatment with 50 mg/day DHEA or P. [ 15 N]Phenylalanine and [ 2 H 4 ]tyrosine tracers were infused, with measurements in plasma and vastus lateralis muscle. Whole‐body protein synthesis per fat‐free mass and muscle protein fractional synthesis rate (FSR) were lower in elderly than in young individuals (P< 0.001), not significantly affected by hormone treatments, and higher in women than in men (P<0.0001), with no sex × age interaction. In regression analyses, peak O 2 consumption (VO 2peak ), resting energy expenditure (REE), and sex were independently associated with muscle FSR, as were VO 2peak , REE, and interactions of sex with insulin‐like growth factor‐II and insulin for whole‐body protein synthesis. Women maintain higher protein synthesis than men across the lifespan as rates decline in both sexes, and neither full replacement of DHEA (in elderly men and women) nor partial replacement of bioavailable T (in elderly men) is able to amend the age‐related declines.— Henderson, G. C., Dhatariya, K., Ford, G. C., Klaus, K. A., Basu, R., Rizza, R. A., Jensen, M. D., Khosla, S., O'Brien, P., Nair, K. S. Higher muscle protein synthesis in women than men across the lifespan, and failure of androgen administration to amend age‐related decrements. FASEB J. 23, 631–641 (2009)
IC‐P2‐108: MRI and 1H MRS markers are complementary in predicting risk of future dementia in mild cognitive impairment
Weigand, Stephen D. , Shiung, Maria M., Whitwell, Jennifer L. , Ivnik, Robert J., O’Brien, Peter C. , Petersen, Ronald C. , Kantarci, Kejal , Negash, Selam , Smith, Glenn E. , Knopman, David S. , Boeve, Bradley F. , Jack, Clifford R.

Alzheimer's & Dementia | July 24, 2008 | Volume: 4 | Issue: 4S_Part_2 | Pages: No page available

10.1016/j.jalz.2008.05.101 Get It

Phase II Study of Dasatinib in Philadelphia Chromosome–Negative Acute and Chronic Myeloid Diseases, Including Systemic Mastocytosis
Verstovšek, Srđan , Tefferi, Ayalew , Cortes, Jörge E. , O’Brien, Susan , Garcia‐Manero, Guillermo , Pardanani, Animesh , Akin, Cem , Faderl, Stefan, Manshouri, Taghi , Thomas, Deborah A. , Kantarjian, Hagop M. , Cortes, Jorge , Verstovsek, Srdan , Akin, Cem , Kantarjian, Hagop

Clinical Cancer Research | June 16, 2008 | Volume: 14 | Issue: 12 | Pages: 3906-3915

10.1158/1078-0432.ccr-08-0366 | PMID 18559612 Get It

Abstract Purpose: Molecular characterization of Philadelphia chromosome–negative (Ph−) chronic myeloproliferative disorders, such as systemic mastocytosis (SM), has provided a clear rationale for investigating novel targeted therapies. The tyrosine kinase (TK) inhibitor dasatinib is 325-fold more potent against Bcr-Abl TK than imatinib in vitro, significantly inhibiting wild-type KIT and platelet-derived growth factor receptor β TKs, and is active against cells carrying the mutant KIT-D816V gene. Experimental Design: In this phase 2, open-label study, the efficacy of dasatinib (140 mg/d) was investigated in 67 patients with various Ph− myeloid disorders, including SM (n = 33; 28 KIT-D816V positive). Results: The overall response rate to dasatinib in patients with SM was 33%. Only two patients, one with SM-myelofibrosis and one with SM-chronic eosinophilic leukemia, achieved complete response (elimination of mastocytosis) lasting for 5 and 16 months, respectively. Both patients were negative for KIT-D816V mutation, had low tryptase levels, abnormal WBC counts, and anemia, and had failed prior therapy with erythropoietin. Additional nine SM patients had symptomatic response, lasting 3 to 18+ months. Complete responses were achieved in two other patients (acute myeloid leukemia and hypereosinophilic syndrome). No responses were observed among patients with myelodysplastic syndromes and primary myelofibrosis. The majority of adverse events were grade 1/2. Conclusion: These data show that dasatinib therapy may benefit a selected group of SM patients, primarily by improving their symptoms, but it does not eliminate the disease in the patients with KIT-D816V mutation.