Publications
Department of Medicine faculty members published more than 3,600 peer-reviewed articles in 2024.
2008
OBJECTIVE
Bariatric surgical procedures have increased exponentially in the United States. Laparoscopic adjustable gastric banding is now promoted as a safer, potentially reversible and effective alternative to Roux-en-Y gastric bypass, the current standard of care. This study evaluated the balance of patient-oriented clinical outcomes for laparoscopic adjustable gastric banding and Roux-en-Y gastric bypass.
METHODS
The MEDLINE database (1966 to January 2007), Cochrane clinical trials database, Cochrane reviews database, and Database of Abstracts of Reviews of Effects were searched using the key terms gastroplasty, gastric bypass, laparoscopy, Swedish band, and gastric banding. Studies with at least 1 year of follow-up that directly compared laparoscopic adjustable gastric banding with Roux-en-Y gastric bypass were included. Resolution of obesity-related comorbidities, percentage of excess body weight loss, quality of life, perioperative complications, and long-term adverse events were the abstracted outcomes.
RESULTS
The search identified 14 comparative studies (1 randomized trial). Few studies reported outcomes beyond 1 year. Excess body weight loss at 1 year was consistently greater for Roux-en-Y gastric bypass than laparoscopic adjustable gastric banding (median difference, 26%; range, 19%-34%; P < .001). Resolution of comorbidities was greater after Roux-en-Y gastric bypass. In the highest-quality study, excess body weight loss was 76% with Roux-en-Y gastric bypass versus 48% with laparoscopic adjustable gastric banding, and diabetes resolved in 78% versus 50% of cases, respectively. Both operating room time and length of hospitalization were shorter for those undergoing laparoscopic adjustable gastric banding. Adverse events were inconsistently reported. Operative mortality was less than 0.5% for both procedures. Perioperative complications were more common with Roux-en-Y gastric bypass (9% vs 5%), whereas long-term reoperation rates were lower after Roux-en-Y gastric bypass (16% vs 24%). Patient satisfaction favored Roux-en-Y gastric bypass (P=.006).
CONCLUSION
Weight loss outcomes strongly favored Roux-en-Y gastric bypass over laparoscopic adjustable gastric banding. Patients treated with laparoscopic adjustable gastric banding had lower short-term morbidity than those treated with Roux-en-Y gastric bypass, but reoperation rates were higher among patients who received laparoscopic adjustable gastric banding. Gastric bypass should remain the primary bariatric procedure used to treat obesity in the United States.
View on PubMed2008
PURPOSE OF REVIEW
Incidences of antimicrobial-resistant infections have increased dramatically over the past several decades and are associated with adverse patient outcomes. Alternative approaches to combat infection are critical and have led to the development of more specific drugs targeted at particular bacterial virulence systems or essential regulatory pathways. The purpose of this review is to highlight the recent developments in antibacterial therapy and the novel approaches toward increasing our therapeutic armory against bacterial infection.
RECENT FINDINGS
Although classic antibiotic development is not occurring rapidly, alternative therapeutics that target specific bacterial virulence systems are progressing from the discovery stage through the Food and Drug Administration approval process. Here we review novel antibodies that target specific virulence systems as well as a variety of newly discovered small molecules that block bacterial attachment, communication systems (quorum sensing) or important regulatory processes associated with virulence gene expression.
SUMMARY
The success of novel therapeutics could significantly change clinical practice. Furthermore, the complications of collateral damage due to antibiotic administration, for example, suprainfections or decreased host immunity due to loss of synergistic bacterial communities, may be minimized using therapeutics that specifically target pathogenic behavior.
View on PubMed2008
BACKGROUND
Studies in persons without HIV infection have compared adipose tissue measured by dual-energy X-ray absorptiometry (DXA) and magnetic resonance imaging (MRI), but no such study has been conducted in HIV-infected (HIV+) subjects, who have a high prevalence of regional fat loss.
OBJECTIVE
We compared DXA- with MRI-measured trunk, leg, arm, and total fat in HIV+ and control subjects.
DESIGN
A cross-sectional analysis was conducted in 877 HIV+ subjects and 260 control subjects in FRAM (Study of Fat Redistribution and Metabolic Change in HIV Infection), stratified by sex and HIV status.
RESULTS
Univariate associations of DXA with MRI were strongest for total and trunk fat (r > or = 0.92) and slightly weaker for leg (r > or = 0.87) and arm (r > or = 0.71) fat. The average estimated limb fat was substantially greater for DXA than for MRI for HIV+ and control men and women (all P < 0.0001). Less of a difference was observed in trunk fat measured by DXA and MRI, but the difference was still statistically significant (P < 0.0001). Bland-Altman plots showed increasing differences and variability. Greater average limb fat in control and HIV+ subjects (both P < 0.0001) was associated with greater differences between DXA and MRI measurements. Because the control subjects had more limb fat than did the HIV+ subjects, greater amounts of fat were measured by DXA than by MRI when control subjects were compared with HIV+ subjects. More HIV+ subjects had leg fat in the bottom decile of the control subjects by DXA than by MRI (P < 0.0001).
CONCLUSIONS
Although DXA- and MRI-measured adipose tissue depots correlate strongly in HIV+ and control subjects, differences increase as average fat increases, particularly for limb fat. DXA may estimate a higher prevalence of peripheral lipoatrophy than does MRI in HIV+ subjects.
View on PubMed2008
CONTEXT
The endocrine system is a common target in pathogenic autoimmune responses, and there has been recent progress in our understanding, diagnosis, and treatment of autoimmune endocrine diseases.
SYNTHESIS
Rapid progress has recently been made in our understanding of the genetic factors involved in endocrine autoimmune diseases. Studies on monogenic autoimmune diseases that include endocrine phenotypes like autoimmune polyglandular syndrome type 1 and immune dysregulation, polyendocrinopathy, enteropathy, X-linked have helped reveal the role of key regulators in the maintenance of immune tolerance. Highly powered genetic studies have found and confirmed many new genes outside of the established role of the human leukocyte antigen locus with these diseases, and indicate an essential role of immune response pathways in these diseases. Progress has also been made in identifying new autoantigens and the development of new animal models for the study of endocrine autoimmunity. Finally, although hormone replacement therapy is still likely to be a mainstay of treatment in these disorders, there are new agents being tested for potentially treating and reversing the underlying autoimmune process.
CONCLUSION
Although autoimmune endocrine disorders are complex in etiology, these recent advances should help contribute to improved outcomes for patients with, or at risk for, these disorders.
View on PubMed2008
INTRODUCTION
Myxomatous mitral valve "degeneration" with prolapse (MVP) is the most frequent form of nonischemic mitral valve disease. In myxomatous valves, interstitial cells express extracellular matrix-degrading enzymes and it has been postulated that matrix metalloproteinases (MMPs) contribute to these changes.
METHODS
We generated mice with cardiac-specific expression of constitutively active MMP-2 under the control of the alpha-myosin heavy chain promoter.
RESULTS
These mice are normal at 4-6 months of age; at 12-14 months the mitral valves and chordae tendineae exhibit severe myxomatous change with echocardiographic MVP. Myxomatous change was also evident to a lesser extent in the aortic valves. Myxomatous changes were heterogeneous and limited to the left side of the heart with major disorganization of collagen bundles within the lamina fibrosa. Alcian blue/PAS-stained valves revealed massive accumulation of acidic glycosoaminoglycans within the lamina spongiosa, consistent with valvular interstitial cell differentiation to a chondrocytic phenotype. Cells with the histologic features of hypertrophied chondrocytes were found within the chordae tendineae and the tips of the mitral papillary muscles.
CONCLUSION
This report demonstrates that increased activity of a single enzyme, MMP-2, within a transgenic context reproduces many of the features of the human MVP syndrome. The cardiac-specific MMP-2 transgenic mouse potentially provides a unique experimental platform for the evaluation of nonsurgical therapies based on the underlying pathophysiology of this disease.
View on PubMed2008
Inhaled air is contaminated with pathogens and particulates that may deposit in the airways and damage the host. In response to these invaders, the airway epithelium has developed innate immune responses that provide a defence against the invaders and protect the airway structure and function. Thus, the epithelium of conducting airways becomes the "battleground" between the invaders and the host. Recent evidence suggests that airway epithelial surface signalling through the epidermal growth factor receptor (EGFR) is a convergent pathway producing innate immune responses to a variety of infectious and noninfectious noxious stimuli. In the present review, the EGFR signalling pathways leading to airway mucin production, neutrophil recruitment (via interleukin-8 production) and airway epithelial repair were examined. The importance of these findings in human airway diseases was also investigated. The current authors suggest that the exaggerated innate immune responses found in chronic inflammatory airway diseases (e.g. chronic obstructive pulmonary disease, cystic fibrosis and severe asthma) contribute to the pathogenesis or the aggravation of these diseases. Potential therapies include inhibition of the various elements of the described epidermal growth factor receptor cascade. In considering each therapeutic intervention, the potential benefits must be considered in relation to potential deleterious effects.
View on PubMed2008
BACKGROUND
Many allergic conditions occur more frequently in African American patients when compared with white patients; however, it is not known whether this represents genetic predisposition or disparate environmental exposures.
OBJECTIVE
We sought to assess the relationship of self-reported race and genetic ancestry to allergic sensitization.
METHODS
We included 601 women enrolled in a population-based cohort study whose self-reported race was African American or white. Genetic ancestry was estimated by using markers that differentiate West African and European ancestry. We assessed the relationship between allergic sensitization (defined as > or =1 allergen-specific IgE results) and both self-reported race and genetic ancestry. Regression models adjusted for sociodemographic variables, environmental exposures, and location of residence.
RESULTS
The average proportion of West African ancestry in African American participants was 0.69, whereas the mean proportion of European ancestry in white participants was 0.79. Self-reported African American race was associated with allergic sensitization when compared with those who reported being white (adjusted odds ratio, 2.19; 95% CI, 1.22-3.93), even after adjusting for other variables. Genetic ancestry was not significantly associated with allergic sensitization after accounting for location of residence (adjusted odds ratio, 2.09 for urban vs suburban residence; 95% CI, 1.32-3.31).
CONCLUSION
Self-reported race and location of residence appeared to be more important predictors of allergic sensitization when compared with genetic ancestry, suggesting that the disparity in allergic sensitization by race might be primarily a result of environmental factors rather than genetic differences.
View on PubMed2008
BACKGROUND
Moringa oleifera is a tropical tree often used as a herbal medicine, including by people who test positive for HIV. Since herbal constituents may interact with drugs via inhibition of metabolizing enzymes, we investigated the effects of extracts of M. oleifera on the CYP3A4-mediated 6beta-hydroxylation of testosterone.
METHODS
Methanolic and aqueous leaf and root of extracts of M. oleifera with concentrations between 0.01 and 10 mg/ml were incubated with testosterone and mixed-sex human liver microsomes in the presence of NADPH. Metabolite concentrations were determined by HPLC. The cytotoxicity of the extracts was tested with HepG2 cells using the MTT formazan assay.
RESULTS
Significant CYP3A4 inhibitory effects were found, with IC50 values of 0.5 and 2.5 mg/ml for leaf-methanol and leaf-water extracts, respectively. Root extracts were less active. Cytotoxicity was observed only with the leaf-water extract (IC50 = 6 mg/ml).
CONCLUSIONS
Further investigation is warranted to elucidate the potential of M. oleifera for clinically significant interactions with antiretroviral and other drugs.
View on PubMed2008