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Dive into the research topics where Jack A. Yanovski is active.

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Featured researches published by Jack A. Yanovski.


Hepatology | 2004

A pilot study of pioglitazone treatment for nonalcoholic steatohepatitis

Kittichai Promrat; Glen Lutchman; Gabriel I. Uwaifo; Renee J. Freedman; Alejandro Soza; Theo Heller; Edward Doo; Marc G. Ghany; Ahalya Premkumar; Yoon Park; T. Jake Liang; Jack A. Yanovski; David E. Kleiner; Jay H. Hoofnagle

Nonalcoholic steatohepatitis (NASH) is a common chronic liver disease for which there is no known effective therapy. A proportion of patients with NASH progress to advanced fibrosis and cirrhosis. NASH is considered one of the clinical features of the metabolic syndrome in which insulin resistance plays a central role. This prospective study evaluates the role of insulin‐sensitizing agent in treatment of NASH. Eighteen nondiabetic patients with biopsy‐proven NASH were treated with pioglitazone (30 mg daily) for 48 weeks. Tests of insulin sensitivity and body composition as well as liver biopsies were performed before and at the end of treatment. By 48 weeks, serum alanine aminotransferase values fell to normal in 72% of patients. Hepatic fat content and size as determined by magnetic resonance imaging decreased, and glucose and free fatty acid sensitivity to insulin were uniformly improved. Histological features of steatosis, cellular injury, parenchymal inflammation, Mallory bodies, and fibrosis were significantly improved from baseline (all P < 0.05). Using strict criteria, histological improvement occurred in two‐thirds of patients. Pioglitazone was well tolerated; the main side effects were weight gain (averaging 4%) and an increase in total body adiposity. In conclusion, these results indicate that treatment with an insulin‐sensitizing agent can lead to improvement in biochemical and histological features of NASH and support the role of insulin resistance in the pathogenesis of this disease. The long‐term safety and benefits of pioglitazone require further study. (HEPATOLOGY 2004;39:188–196.)


The Lancet | 1998

Visceral abdominal-fat accumulation associated with use of indinavir

Kirk D. Miller; Elizabeth Jones; Jack A. Yanovski; Rani Shankar; Irwin Feuerstein; Judith Falloon

BACKGROUND After the addition of the protease inhibitor indinavir to combination drug regimens for HIV-1 infection, some patients have experienced an increase in abdominal girth with symptoms of abdominal fullness, distension, or bloating. We aimed to find out whether this collection of symptoms was associated with changes in abdominal fat and whether such changes were associated with indinavir use. METHODS Abdominal computed tomography was used in ten HIV-1-positive patients who had such abdominal symptoms to measure total adipose tissue (TAT) and visceral adipose tissue (VAT) at the umbilicus (L4 vertebral level). The VAT:TAT ratio in the ten cases was compared with that in ten HIV-1-infected patients who had been using indinavir without abdominal symptoms for at least 6 months and ten HIV-1-infected patients who were not using indinavir. FINDINGS The mean VAT:TAT ratios for the three groups-non-users, symptom-free indinavir users, and symptomatic indinavir users-were 0.40 (SD 0.15), 0.59 (0.18), and 0.70 (0.20), respectively (p=0.004). The VAT:TAT ratio correlated with duration of indinavir use (r=0.47, p=0.01). The mean areas of VAT for the three groups were 106 cm2 (SD 72), 141 cm2 (65) and 202 cm2 (93), respectively (p=0.03). The mean body-mass index of the groups was similar, and patients in the two indinavir groups did not gain a significant amount of weight after starting the drug. Serum triglyceride values increased after starting indinavir and correlated with VAT:TAT ratios. INTERPRETATION Our data suggest that some HIV-1-infected patients on indinavir treatment accumulate intra-abdominal fat that may cause abdominal symptoms. Recent evidence suggests that other HIV-1 protease inhibitors may be associated with changes in body-fat distribution. Larger studies of protease-inhibitor treatment are needed to investigate this association further and to investigate metabolic or endocrine mechanisms that may underlie this phenomenon.


The New England Journal of Medicine | 2008

Phenotype and course of Hutchinson-Gilford progeria syndrome

Melissa Merideth; Leslie B. Gordon; Sarah Clauss; Vandana Sachdev; Ann C.M. Smith; Monique B. Perry; Carmen C. Brewer; Christopher Zalewski; H. Jeffrey Kim; Beth Solomon; Brian P. Brooks; Lynn H. Gerber; Maria L. Turner; Demetrio L. Domingo; Thomas C. Hart; Jennifer Graf; James C. Reynolds; Andrea Gropman; Jack A. Yanovski; Marie Gerhard-Herman; Francis S. Collins; Elizabeth G. Nabel; Richard O. Cannon; William A. Gahl; Wendy J. Introne

BACKGROUND Hutchinson-Gilford progeria syndrome is a rare, sporadic, autosomal dominant syndrome that involves premature aging, generally leading to death at approximately 13 years of age due to myocardial infarction or stroke. The genetic basis of most cases of this syndrome is a change from glycine GGC to glycine GGT in codon 608 of the lamin A (LMNA) gene, which activates a cryptic splice donor site to produce abnormal lamin A; this disrupts the nuclear membrane and alters transcription. METHODS We enrolled 15 children between 1 and 17 years of age, representing nearly half of the worlds known patients with Hutchinson-Gilford progeria syndrome, in a comprehensive clinical protocol between February 2005 and May 2006. RESULTS Clinical investigations confirmed sclerotic skin, joint contractures, bone abnormalities, alopecia, and growth impairment in all 15 patients; cardiovascular and central nervous system sequelae were also documented. Previously unrecognized findings included prolonged prothrombin times, elevated platelet counts and serum phosphorus levels, measured reductions in joint range of motion, low-frequency conductive hearing loss, and functional oral deficits. Growth impairment was not related to inadequate nutrition, insulin unresponsiveness, or growth hormone deficiency. Growth hormone treatment in a few patients increased height growth by 10% and weight growth by 50%. Cardiovascular studies revealed diminishing vascular function with age, including elevated blood pressure, reduced vascular compliance, decreased ankle-brachial indexes, and adventitial thickening. CONCLUSIONS Establishing the detailed phenotype of Hutchinson-Gilford progeria syndrome is important because advances in understanding this syndrome may offer insight into normal aging. Abnormal lamin A (progerin) appears to accumulate with aging in normal cells. (ClinicalTrials.gov number, NCT00094393.)


Pediatrics | 2006

Orthopedic Complications of Overweight in Children and Adolescents

Erica Taylor; Kelly R. Theim; Margaret C. Mirch; Samareh Ghorbani; Marian Tanofsky-Kraff; Diane C. Adler-Wailes; Sheila M. Brady; James C. Reynolds; Karim A. Calis; Jack A. Yanovski

OBJECTIVE. Few studies have quantified the prevalence of weight-related orthopedic conditions in otherwise healthy overweight children. The goal of the present investigation was to describe the musculoskeletal consequences of pediatric overweight in a large pediatric cohort of children that included severely overweight children. METHODS. Medical charts from 227 overweight and 128 nonoverweight children and adolescents who were enrolled in pediatric clinical studies at the National Institutes of Health from 1996 to 2004 were reviewed to record pertinent orthopedic medical history and musculoskeletal complaints. Questionnaire data from 183 enrollees (146 overweight) documented difficulties with mobility. In 250, lower extremity alignment was determined by bilateral metaphyseal-diaphyseal and anatomic tibiofemoral angle measurements made from whole-body dual-energy x-ray absorptiometry scans. RESULTS. Compared with nonoverweight children, overweight children reported a greater prevalence of fractures and musculoskeletal discomfort. The most common self-reported joint complaint among those who were questioned directly was knee pain (21.4% overweight vs 16.7% nonoverweight). Overweight children reported greater impairment in mobility than did nonoverweight children (mobility score: 17.0 ± 6.8 vs 11.6 ± 2.8). Both metaphyseal-diaphyseal and anatomic tibiofemoral angle measurements showed greater malalignment in overweight compared with nonoverweight children. CONCLUSIONS. Reported fractures, musculoskeletal discomfort, impaired mobility, and lower extremity malalignment are more prevalent in overweight than nonoverweight children and adolescents. Because they affect the likelihood that children will engage in physical activity, orthopedic difficulties may be part of the cycle that perpetuates the accumulation of excess weight in children.


Diabetes | 2006

Hyperphagia, severe obesity, impaired cognitive function, and hyperactivity associated with functional loss of one copy of the brain-derived neurotrophic factor (BDNF) gene

Juliette Gray; Giles S. H. Yeo; James J. Cox; Jenny Morton; Anna-Lynne R. Adlam; Julia M. Keogh; Jack A. Yanovski; Areeg El Gharbawy; Joan C. Han; Y.C. Loraine Tung; John R. Hodges; F. Lucy Raymond; Stephen O’Rahilly; I. Sadaf Farooqi

The neurotrophin brain-derived neurotrophic factor (BDNF) inhibits food intake, and rodent models of BDNF disruption all exhibit increased food intake and obesity, as well as hyperactivity. We report an 8-year-old girl with hyperphagia and severe obesity, impaired cognitive function, and hyperactivity who harbored a de novo chromosomal inversion, 46,XX,inv(11)(p13p15.3), a region encompassing the BDNF gene. We have identified the proximal inversion breakpoint that lies 850 kb telomeric of the 5′ end of the BDNF gene. The patient’s genomic DNA was heterozygous for a common coding polymorphism in BDNF, but monoallelic expression was seen in peripheral lymphocytes. Serum concentration of BDNF protein was reduced compared with age- and BMI-matched subjects. Haploinsufficiency for BDNF was associated with increased ad libitum food intake, severe early-onset obesity, hyperactivity, and cognitive impairment. These findings provide direct evidence for the role of the neurotrophin BDNF in human energy homeostasis, as well as in cognitive function, memory, and behavior.


Journal of Consulting and Clinical Psychology | 2004

Eating-disordered behaviors, body fat, and psychopathology in overweight and normal-weight children.

Marian Tanofsky-Kraff; Susan Z. Yanovski; Denise E. Wilfley; Cheri Marmarosh; Christina Marcondes Morgan; Jack A. Yanovski

This study examined eating-disordered pathology in relation to psychopathology and adiposity in 162 non-treatment-seeking overweight (OW) and normal weight (NW) children, ages 6-13 years. Participants experienced objective or subjective binge eating (S/OBE; loss-of-control eating), objective overeating (OO), or no episodes (NE). OW children experienced significantly higher eating-disordered cognitions and behaviors than NW children and more behavior problems than NW children: 9.3% endorsed S/OBEs, 20.4% reported OOs, and 70.4% reported NEs. OW children reported S/OBEs more frequently than did NW children (p =.01), but similar percentages endorsed OOs. S/OBE children experienced greater eating-disordered cognitions (ps from <.05 to <.01) and had higher body fat (p <.05) than OOs or NEs. OOs are common in childhood, but S/OBEs are more prevalent in OW children and associated with increased adiposity and eating-disordered cognitions.


The New England Journal of Medicine | 2000

A PROSPECTIVE STUDY OF HOLIDAY WEIGHT GAIN

Jack A. Yanovski; Susan Z. Yanovski; Kara N. Sovik; Tuc T. Nguyen; Patrick M. O'Neil; Nancy G. Sebring

BACKGROUND It is commonly asserted that the average American gains 5 lb (2.3 kg) or more over the holiday period between Thanksgiving and New Years Day, yet few data support this statement. METHODS To estimate actual holiday-related weight variation, we measured body weight in a convenience sample of 195 adults. The subjects were weighed four times at intervals of six to eight weeks, so that weight change was determined for three periods: preholiday (from late September or early October to mid-November), holiday (from mid-November to early or mid-January), and postholiday (from early or mid-January to late February or early March). A final measurement of body weight was obtained in 165 subjects the following September or October. Data on other vital signs and self-reported health measures were obtained from the patients in order to mask the main outcome of interest. RESULTS The mean (+/-SD) weight increased significantly during the holiday period (gain, 0.37+/-1.52 kg; P<0.001), but not during the preholiday period (gain, 0.18+/-1.49 kg; P=0.09) or the postholiday period (loss, 0.07+/-1.14 kg; P=0.36). As compared with their weight in late September or early October, the study subjects had an average net weight gain of 0.48+/-2.22 kg in late February or March (P=0.003). Between February or March and the next September or early October, there was no significant additional change in weight (gain, 0.21 kg+/-2.3 kg; P=0.13) for the 165 participants who returned for follow-up. CONCLUSIONS The average holiday weight gain is less than commonly asserted. Since this gain is not reversed during the spring or summer months, the net 0.48-kg weight gain in the fall and winter probably contributes to the increase in body weight that frequently occurs during adulthood.


International Journal of Obesity | 2007

Inflammation and iron deficiency in the hypoferremia of obesity

Lisa B. Yanoff; Cm Menzie; B Denkinger; Nancy G. Sebring; T McHugh; Alan T. Remaley; Jack A. Yanovski

Context:Obesity is associated with hypoferremia, but it is unclear if this condition is caused by insufficient iron stores or diminished iron availability related to inflammation-induced iron sequestration.Objective:To examine the relationships between obesity, serum iron, measures of iron intake, iron stores and inflammation. We hypothesized that both inflammation-induced sequestration of iron and true iron deficiency were involved in the hypoferremia of obesity.Design:Cross-sectional analysis of factors anticipated to affect serum iron.Setting:Outpatient clinic visits.Patients:Convenience sample of 234 obese and 172 non-obese adults.Main outcome measures:Relationships between serum iron, adiposity, and serum transferrin receptor, C-reactive protein, ferritin, and iron intake analyzed by analysis of covariance and multiple linear regression.Results:Serum iron was lower (75.8±35.2 vs 86.5±34.2 g/dl, P=0.002), whereas transferrin receptor (22.6±7.1 vs 21.0±7.2 nmol/l, P=0.026), C-reactive protein (0.75±0.67 vs 0.34±0.67 mg/dl, P<0.0001) and ferritin (81.1±88.8 vs 57.6±88.7 μg/l, P=0.009) were higher in obese than non-obese subjects. Obese subjects had a higher prevalence of iron deficiency defined by serum iron (24.3%, confidence intervals (CI) 19.3–30.2 vs 15.7%, CI 11.0–21.9%, P=0.03) and transferrin receptor (26.9%, CI 21.6–33.0 vs 15.7%, CI 11.0–21.9%, P=0.0078) but not by ferritin (9.8%, CI 6.6–14.4 vs 9.3%, CI 5.7–14.7%, P=0.99). Transferrin receptor, ferritin and C-reactive protein contributed independently as predictors of serum iron.Conclusions:The hypoferremia of obesity appears to be explained both by true iron deficiency and by inflammatory-mediated functional iron deficiency.


Pediatrics | 2006

A Prospective Study of Psychological Predictors of Body Fat Gain Among Children at High Risk for Adult Obesity

Marian Tanofsky-Kraff; Marc L. Cohen; Susan Z. Yanovski; Christopher Cox; Kelly R. Theim; Margaret F. Keil; James C. Reynolds; Jack A. Yanovski

OBJECTIVE. Limited data suggest that psychological factors, including binge eating, dieting, and depressive symptoms, may predispose children to excessive weight gain. We investigated the relationship between baseline psychological measures and changes in body fat (measured with dual-energy x-ray absorptiometry) over time among children thought to be at high risk for adult obesity. METHODS. A cohort study of a convenience sample of children (age: 6–12 years) recruited from Washington, DC, and its suburbs was performed. Subjects were selected to be at increased risk for adult obesity, either because they were overweight when first examined or because their parents were overweight. Children completed questionnaires at baseline that assessed dieting, binge eating, disordered eating attitudes, and depressive symptoms; they underwent measurements of body fat mass at baseline and annually for an average of 4.2 years (SD: 1.8 years). RESULTS. Five hundred sixty-eight measurements were obtained between July 1996 and December 2004, for 146 children. Both binge eating and dieting predicted increases in body fat. Neither depressive symptoms nor disturbed eating attitudes served as significant predictors. Children who reported binge eating gained, on average, 15% more fat mass, compared with children who did not report binge eating. CONCLUSIONS. Children’s reports of binge eating and dieting were salient predictors of gains in fat mass during middle childhood among children at high risk for adult obesity. Interventions targeting disordered eating behaviors may be useful in preventing excessive fat gain in this high-risk group.


Pharmacotherapy | 2000

Orlistat, a New Lipase Inhibitor for the Management of Obesity

Amy M Heck; Jack A. Yanovski; Karim A. Calis

Orlistat, a weight‐loss agent with a novel mechanism of action, recently was approved by the Food and Drug Administration for the treatment of obesity. It inhibits gastric and pancreatic lipases in the lumen of the gastrointestinal tract to decrease systemic absorption of dietary fat. In several trials lasting up to 2 years, orlistat was more effective than diet alone for weight reduction and maintenance of lost weight. Orlistat treatment also results in modest improvements in total cholesterol, low‐density lipoprotein, blood pressure, and fasting glucose and insulin concentrations. The major adverse effects are gastrointestinal, usually occur early in therapy, and tend to decrease with continued treatment. Because orlistat may decrease the absorption of fat‐soluble vitamins, a standard multiple‐vitamin supplement is recommended daily during therapy to prevent abnormalities in vitamin serum concentrations. The potential for severe gastrointestinal discomfort and the modest degree of weight loss may limit the agents clinical utility. Its long‐term safety and effectiveness for weight maintenance, cost‐effectiveness of treatment, and overall reduction in obesity‐related morbidity and mortality remain to be determined.

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Marian Tanofsky-Kraff

Uniformed Services University of the Health Sciences

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Susan Z. Yanovski

National Institutes of Health

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Sheila M. Brady

National Institutes of Health

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James C. Reynolds

National Institutes of Health

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Gordon B. Cutler

National Institutes of Health

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Nancy G. Sebring

National Institutes of Health

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Joan C. Han

University of Tennessee Health Science Center

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Andrew P. Demidowich

National Institutes of Health

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Lisa M. Ranzenhofer

Uniformed Services University of the Health Sciences

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