bluuebunny/crossref_metadata_2025 huggingface dataset:
Medical Student Research Exposure via a Series of Modular Research Programs
Authors: Langhammer Christopher G. , Garg Karan , Neubauer Judith A. , Rosenthal Susan , Kinzy Terri Goss
Published: May 2016

Background

The falling percentage of doctors of medicine applying for National Institute of Health-funded research grants is 1 indicator that physician-scientists are a disappearing breed. This is occurring at a time when increased translational, disease-oriented, patient-oriented, and clinical research are national goals. One of the keys to providing sufficient numbers of physician-scientists to support this goal is the active targeting of medical students. We hypothesize that an improved research program infrastructure and responsiveness to changing student needs will increase student participation in research-oriented electives.

Methods

We have developed a student research program consisting of 2 Students Interested in Research noncredit electives (lecture and laboratory based), summer fellowships, support for year-out fellowships, and a Distinction in Research program that spans undergraduate medical education. Student participation and short-term research outcomes from fall 2004 through spring 2008 are analyzed to examine program efficacy.

Results

Students involved in the early parts of the program initially experienced higher application and success rates for summer funding opportunities, but as the program has matured, these rates have fallen in line with the class average. Independently, students participating in later portions of the program increasingly submit or publish a first author paper and have taken a year off for research during medical school. Overlap of participation in the programs is generally smaller than expected.

Conclusion

Although structured programs can provide step-wise research experiences of increasing intensity, students may not experience a training pipeline in which each stage relies on those before and after, and instead may sample an a la carte selection of research-based enrichment opportunities.
Effect of Statins on Fasting Plasma Glucose in Diabetic and Nondiabetic Patients
Authors: Sukhija Rishi , Prayaga Sastry , Marashdeh Mohammad , Bursac Zoran , Kakar Priyanka , Bansal Darpan , Sachdeva Rajesh , Kesan Sree Hari , Mehta Jawahar L.
Published: May 2016

Background

The 3-hydroxy-3-methylglutaryl-CoA reductase inhibitors (statins) reduce serum cholesterol level and cardiovascular morbidity and mortality. However, the effect of statins on glucose metabolism is unclear. Some studies have suggested that statins may cause hyperglycemia by increasing calcium concentration in the islet cells leading to decrease in insulin release or by decreasing GLUT 4-mediated peripheral glucose uptake.

Methods

We analyzed the data in 345,417 patients (mean age 61 ± 15 years, 94% males, 6% diabetic, 20% statin users) from the Veterans Affairs VISN 16 database. We studied change in fasting plasma glucose (FPG) in this population over a mean time of 2 years between the first available measurement and the last measurement form the most recent recorded visit. Data were limited to patients who had 2 FPG measurements. Diagnosis of diabetes had to be present before the first FPG measurement.

Results

Among patients without diabetes, FPG increased with statin use from 98 mg/dL to 105 mg/dL, and among nonstatin users, FPG increased from 97 mg/dL to 101 mg/dL (increase in FPG with statin use P < 0.0001). Among patients with diabetes, FPG increased with statin use from 102 mg/dL to 141 mg/dL, and among nonstatin users, FPG increased from 100 mg/dL to 129 mg/dL (increase in FPG with statin use; P < 0.0001). After adjustment for age and use of aspirin, β-blockers, and angiotensin-converting enzyme inhibitors, the change in FPG in nondiabetic statin users was 7 mg/dL (vs 5 mg/dL in nonstatin users, P < 0.0001) and for diabetic statin users it was 39 mg/dL (vs 32 in nonstatin users, P < 0.0001).

Conclusions

Statin use is associated with a rise of FPG in patients with and without diabetes. This relationship between statin use and rise in FPG is independent of age and use of aspirin, β-blockers, and angiotensin-converting enzyme inhibitors.
Strategies for Innovation and Interdisciplinary Translational Research
Authors: Berglund Lars , Tarantal Alice
Published: May 2016

The National Institutes of Health's Clinical and Translational Science Award program has had a profound impact upon the way research is conducted at the University of California, Davis. University of California, Davis was among the first cohort of 12 institutions to receive National Institutes of Health funding for this award, and created its Clinical and Translational Science Center (CTSC) in 2006. The presence of a CTSC has led us to develop new ways of bringing together and supporting researchers from diverse fields, and the CTSC has impacted on virtually every area and infrastructure resource involved in supporting clinical and translational research at our institution.
The Anti-Inflammatory Effects of Prostaglandins
Authors: Scher Jose U. , Pillinger Michael H.
Published: May 2016

Long regarded as proinflammatory molecules, prostaglandins (PGs) also have anti-inflammatory effects. Both prostaglandin D2 (PGD2) and its dehydration end product 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) seem to play important roles in regulating inflammation, via both receptor-dependent (DP1 and DP2 receptors) and receptor-independent mechanisms. Intracellular effects of PGD2 and 15d-PGJ2 that may suppress inflammation include inhibition of nuclear factor-κB (NF-κB) by multiple mechanisms (IκB kinase inhibition and blockade of NF-κB nuclear binding) and activation of peroxisome proliferator-activated receptor-γ (PPAR-γ). Prostaglandin F2α (PGF2α) may also have important anti-inflammatory effects, although current data are limited. In animal models, expression of both PGD and PGF synthases declines during acute inflammation, only to rise again during the resolution phase, suggesting their possible role in resolving inflammation. Prostaglandin E2 (PGE2), the classic model of a proinflammatory lipid mediator, also has anti-inflammatory effects that are both potent and context dependent. Thus, accumulating data suggest that PGs not only participate in initiation, but may also actively contribute to the resolution of inflammation. Indeed, classic inhibitors of PG synthesis such as nonselective and cyclooxygenase-2 (COX-2) selective inhibitors (nonsteroidal anti-inflammatory drugs) may actually prolong inflammation when administered during the resolution phase. These effects may regulate not only tissue inflammation but also vascular disease, possibly shedding light on the controversy surrounding nonsteroidal anti-inflammatory drug use and its relation to myocardial infarction. In this review, we summarize the current understanding of PGs as dichotomous molecules in the inflammatory process.
Disruption of Cholesterol Efflux by Coxib Medications and Inflammatory Processes: Link to Increased Cardiovascular Risk
Authors: Reiss Allison B. , Anwar Farah , Chan Edwin S.L. , Anwar Kamran
Published: May 2016

Atherosclerosis is a chronic progressive disease that is a major contributor to cardiac death. It is characterized by inflammation and cholesterol deposition in the arterial wall. Excess cholesterol accumulation occurs as a result of an imbalance between delivery and removal and leads to formation of lipid-laden foam cells. Removal of cholesterol through a process known as reverse cholesterol transport requires the coordinated functioning of a number of genes including the P450 27-hydroxylase and the adenosine triphosphate-binding cassette transporter A1 (ABCA1). Reverse cholesterol transport is a key defense against atheroma formation. This review discusses the role of inflammatory processes in impeding reverse cholesterol transport. Particular emphasis is placed on the disruption of cholesterol outflow observed in the presence of cyclooxygenase inhibitors in cultured monocytes/macrophages. These inhibitors, which are used clinically to relieve pain and inflammation, have been associated with increased risk of cardiovascular disease and myocardial infarction. We explore the relationship between suppression of reverse cholesterol transport and harmful cardiac effects of coxibs.
Inhibition of 3-Hydroxy-3-Methyl-Glutaryl-Coenzyme a Reductase Reduces Leukocyte Recruitment and Hepatocyte Apoptosis in Endotoxin-Induced Liver Injury
Authors: Slotta Jan E. , Laschke Matthias W. , Wang Yusheng , Schilling Martin K. , Menger Michael D. , Thorlacius Henrik
Published: May 2016

Background

Endotoxemia is well known to be associated with an excessive host response to bacteria or microbial compounds, resulting in systemic inflammation and organ injury. The aim of the present study was to examine the effects of simvastatin on endotoxemic liver injury.

Methods

Male C57BL/6J mice were challenged intraperitoneally with 0.5 mg/kg Escherichia coli-lipopolysaccharide (LPS) and 0.9 g/kg d-galactosamine (Gal). Mice were pretreated with 0.2 mg/kg simvastatin. Lipopolysaccharide/d-Gal-injected mice without simvastatin served as endotoxemic controls, and sham mice served as negative controls. Additional mice were challenged with LPS/d-Gal and co-treated with simvastatin and 10 mg/kg mevalonate to determine the role of 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase. After 6 hours of endotoxemia serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities as well as caspase-3 and myeloperoxidase activity were determined.

Results

Endotoxemia caused a substantial hepatocellular injury as indicated by significantly elevated serum ALT and AST levels and hepatocellular apoptosis. Leukocyte infiltration in the liver was significantly elevated in endotoxemic mice. Simvastatin significantly reduced endotoxin-induced hepatocellular damage and apoptosis. Moreover, hepatic accumulation of leukocytes was attenuated by simvastatin in endotoxemic animals. Co-administration of mevalonate abolished protective effects of simvastatin on endotoxin-provoked increases in ALT, AST, and hepatocellular apoptosis as well as leukocyte recruitment.

Conclusions

Simvastatin has the capacity to prevent endotoxemic liver injury by inhibiting leukocyte infiltration and hepatocellular apoptosis. These protective effects exerted by simvastatin are dependent on the 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase pathway. Thus, simvastatin may represent a potential approach to prevent endotoxemia-associated liver dysfunction.
Changes of Red Blood Cell Surface Markers in a Blood Doping Model of Neocytolysis
Authors: Chang Chung-Che , Chen Yayan , Modi Kapil , Awar Omar G. , Alfrey Clarence P. , Rice Lawrence
Published: May 2016

Background

Neocytolysis, the selective hemolysis of young circulating red blood cells (RBCs), contributes to the physiologic control of red cell mass and to pathophysiologic phenomena such as anemia of renal disease, anemia after spaceflight, and blood doping by athletes. Progress in understanding the process is hampered by the lack of established markers to distinguish young from older RBC.

Methods

Twelve potentially informative RBC surface markers were assayed by flow cytometry in normal blood samples, and 4 were preferentially expressed in young RBC. To create a model of neocytolysis, 3 normal volunteers had recombinant human erythropoietin (rhEpo) administered until mild erythrocytosis occurred, then were studied upon rhEpo withdrawal.

Results

Neocytolysis ensued that most evident from a rapid rise in serum ferritin as the iron from young RBC was transferred back to stores. Five additional volunteers had surface markers monitored during and after rhEpo administration. Three subjects with marginal baseline iron stores had blunted response to rhEpo, no significant neocytolysis, and no change in RBC surface marker expression. Two subjects with adequate baseline iron stores developed erythrocytosis followed by neocytolysis. Decreased expression of CD44 (homing-associated cell adhesion molecule) and CD71 (transferrin receptor) seemed to correlate best with neocytolysis; CD35 (complement receptor) less so. Of note, further studies are needed to determine if these changes are causative of red cell destruction.

Conclusion

This study begins to establish a human model of neocytolysis, to establish markers differentiating young and old RBC, and to establish a basis for better definition of the process. Although our study is preliminary, the results support the possibility that flow could be useful to detect blood doping because neocytolysis should predictably occur in athletes who surreptitiously blood dope.
Mutations in COL1A1 of Type I Collagen Genes in Chinese Patients with Osteogenesis Imperfecta
Authors: Wang Zhuo , Yang Zheng , Ke Zunfu , Yang Shicong , Shi Huijuan , Wang Liantang
Published: May 2016

Background

Osteogenesis imperfecta (OI) is an inherited bone disease caused by mutations in collagen genes. Because these mutations occur at a wide variety of sites in the genes and differ among populations, we studied the COL1A1 gene in Chinese with OI and compared the results with findings form other populations.

Methods

COL1A1 gene mutations were detected by polymerase chain reaction and sequencing from 3 unrelated families and 1 sporadic case in Chinese.

Results

Four COL1A1 mutations that were novel were found. The patients' clinical characteristics were variable, even within the same family. Notably, some of the novel COL1A1 variants were at the same nucleotide positions as previously described but with different nucleotide changes. In addition, we also found 1 patient with OI with 2 mutations in the same haplotypes.

Conclusions

We discuss the differences in phenotype related to the specific mutation sites. Although there have been many reports on mutations of COL1A1 and COL1A2, few cases have been reported in Chinese. Our data showed that the COL1A1 gene mutation might also play an important role in OI among Chinese. The Han Chinese represent a quarter of the world's population, and we believe that our new data contributes to fill in the type I collagen mutation map. We thought that the patient with OI could have 2 mutations in the same haplotypes, without limit to 1 mutation.
Fragile X-Associated Tremor/Ataxia Syndrome: Clinical Phenotype, Diagnosis, and Treatment
Authors: Leehey Maureen A.
Published: May 2016

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder caused by a CGG repeat expansion in the premutation range (55-200) in the fragile X mental retardation 1 gene. Onset is typically in the early seventh decade, and men are principally affected. The major signs are cerebellar gait ataxia, intention tremor, frontal executive dysfunction, and global brain atrophy. Other frequent findings are parkinsonism (mild), peripheral neuropathy, psychiatric symptoms (depression, anxiety, and agitation), and autonomic dysfunction. The clinical presentation is heterogeneous, with individuals presenting with varied dominating signs, such as tremor, dementia, or neuropathy. Magnetic resonance imaging shows atrophy and patchy white matter lesions in the cerebral hemispheres and middle cerebellar peduncles. The latter has been designated the middle cerebellar peduncle sign, which occurs in about 60% of affected men, and is relatively specific for FXTAS. Affected females generally have less severe disease, less cognitive decline, and some symptoms different from that of men, for example, muscle pain. Management of FXTAS is complex and includes assessment of the patient's neurological and medical deficits, treatment of symptoms, and provision of relevant referrals, especially genetic counseling. Treatment is empirical, based on anecdotal experience and on knowledge of what works for symptoms of other disorders that also exist in FXTAS. Presently, the disorder is underrecognized because the first published report was only in 2001 and because the presentation is variable and mainly consists of a combination of signs common in the elderly. However, accurate diagnosis is critical for the patient and for the family because they need education regarding their genetic and health risks.
Leptin Deficiency: Clinical Implications and Opportunities for Therapeutic Interventions
Authors: Blüher Susan , Shah Sunali , Mantzoros Christos S.
Published: May 2016

The discovery of leptin has significantly advanced our understanding of the metabolic importance of adipose tissue and has revealed that both leptin deficiency and leptin excess are associated with severe metabolic, endocrine, and immunological consequences. We and others have shown that a prominent role of leptin in humans is to mediate the neuroendocrine adaptation to energy deprivation. Humans with genetic mutations in the leptin and leptin receptor genes have deregulated food intake and energy expenditure leading to a morbidly obese phenotype and a disrupted regulation in neuroendocrine and immune function and in glucose and fat metabolism. Observational and interventional studies in humans with (complete) congenital leptin deficiency caused by mutations in the leptin gene or with relative leptin deficiency as seen in states of negative energy balance such as lipoatrophy, anorexia nervosa, or exercise-induced hypothalamic and neuroendocrine dysfunction have contributed to the elucidation of the pathophysiological role of leptin in these conditions and of the clinical significance of leptin administration in these subjects. More specifically, interventional studies have demonstrated that several neuroendocrine, metabolic, or immune disturbances in these states could be restored by leptin administration. Leptin replacement therapy is currently available through a compassionate use program for congenital complete leptin deficiency and under an expanded access program to subjects with leptin deficiency associated with congenital or acquired lipoatrophy. In addition, leptin remains a potentially forthcoming treatment for several other states of energy deprivation including anorexia nervosa or milder forms of hypothalamic amenorrhea pending appropriate clinical trials.
The Applicability of Lean and Six Sigma Techniques to Clinical and Translational Research
Authors: Schweikhart Sharon A. , Dembe Allard E.
Published: May 2016

Background

Lean and Six Sigma are business management strategies commonly used in production industries to improve process efficiency and quality. During the past decade, these process improvement techniques increasingly have been applied outside the manufacturing sector, for example, in health care and in software development. This article concerns the potential use of Lean and Six Sigma in improving the processes involved in clinical and translational research. Improving quality, avoiding delays and errors, and speeding up the time to implementation of biomedical discoveries are prime objectives of the National Institutes of Health (NIH) Roadmap for Medical Research and the NIH's Clinical and Translational Science Award program.

Methods

This article presents a description of the main principles, practices, and methods used in Lean and Six Sigma. Available literature involving applications of Lean and Six Sigma to health care, laboratory science, and clinical and translational research is reviewed. Specific issues concerning the use of these techniques in different phases of translational research are identified.

Results

Examples of Lean and Six Sigma applications that are being planned at a current Clinical and Translational Science Award site are provided, which could potentially be replicated elsewhere. We describe how different process improvement approaches are best adapted for particular translational research phases.

Conclusions

Lean and Six Sigma process improvement methods are well suited to help achieve NIH's goal of making clinical and translational research more efficient and cost-effective, enhancing the quality of the research, and facilitating the successful adoption of biomedical research findings into practice.
Distribution of Endothelial Nitric Oxide Synthase Gene Polymorphisms in Turkish Population
Authors: Sinici Incilay , Karahan Sevilay , Atalar Enver
Published: May 2016

Nitric oxide (NO) is the major mediator in the regulation of vascular homeostasis. It is synthesized by endothelium from arginine with the catalytic help of endothelial NO synthase ( eNOS). Polymorphisms in the eNOS gene have been associated inconsistently with many vascular diseases. Conflicting results may arise from ethnic variations, notably in control-case studies. Therefore, to obtain reliable information and improve the design of such genetic association studies, we examined the distribution of genetic alleles of 3 clinically relevant eNOS polymorphisms (the variable number of tandem 27-base pair [bp] repeats in intron 4, T-786C in promoter, and G894T in exon 7) in 300 healthy Turkish individuals with a mean age of 50.07 (SD 12.15) years (range, 22-78 years; 50.7% men and 49.3% women). The haplotype frequency was estimated and associations between 3 polymorphisms were evaluated. We discussed the similarity and differences in the distribution of alleles with other populations. The allele frequencies were 45.3%, 48%, and 62.7% for GG of exon 7, TT of promoter, and bb of intron 4 (wild types), respectively. The most common haplotype combines the wild-type alleles (G-T-b) for all 3 polymorphisms (estimated frequency, 37.6%). The linkage analysis between each pairwise combination showed specific associations between T-786C polymorphism in promotor and G894T polymorphism in exon 7 (positive D′ value, +0.3387). No significant correlation was found in the genotype distribution of the 3 polymorphisms with age, sex, and obesity. Our eNOS gene allele distributions resemble those of Caucasians and white populations. Our data showed ethnic differences with other populations in the allele distribution of eNOS gene besides conserved distribution of these polymorphisms in Turkish population. This study produced a reference control data for the 3 eNOS polymorphisms in Turkish population and will be helpful in planning eNOS association studies in vascular disease.
Influence of Nuclear Factor κB Activation on Inflammatory Mediators of Alveolar Macrophages in Rats with Acute Necrotizing Pancreatitis
Authors: Sailai Yalikun , Yu Xiao , Baiheti Paerhati , Tang Huayong , Li Yongguo , Xu Ming
Published: May 2016

Aim

To investigate the potential influence of nuclear factor κB (NF-κB) activation on the inflammatory mediators secreted by alveolar macrophages (AMs) in rats with acute necrotizing pancreatitis (ANP) and to evaluate the effect of an inhibitor of NF-κB- N-acetylcysteine (NAC).

Methods

Ninety male Sprague-Dawley rats were randomly divided into 3 groups, 30 of each: control, ANP, and ANP plus NAC groups. The ANP rat models were established by a retrograde injection of 5% sodium taurocholate into the pancreatic duct. In addition to sodium taurocholate, the ANP plus NAC group received intravenous infusion of NAC (25 mg/100 g). At the sixth hour after modeling, the protein content of the bronchoalveolar lavage fluid, the myeloperoxidase in the lung tissue, and the transforming growth factor α and the nitric oxide (NO) secreted by AMs were determined. The histopathologic changes of the pancreas and the lung were observed under light microscope, and NF-κB activation of AMs was detected.

Results

The protein content of the bronchoalveolar lavage fluid and the myeloperoxidase level of the lung tissue showed a significant increase in the ANP group as compared with the NAC-administered group. The levels of transforming growth factor α and NO secreted by AMs in the ANP and the ANP plus NAC group rose significantly over that in the control group, and there was a significant difference between them. Although they were still higher than those in the control group, the pancreas destruction and the lung injury were slighter in the ANP plus NAC group and the activation of NF-κB was lower in the ANP plus NAC group as compared with that in the ANP group.

Conclusions

The correlation between the NF-κB activation, the up-regulation of the inflammatory mediators secreted by AMs, and the tissue damage suggests a key influence of NF-κB in the pathogenesis of ANP. Inhibition of NF-κB activation may reverse the lung injury of ANP.
Validation of Duruöz Hand Index for Diabetic Hand Dysfunction
Authors: Turan Yasemin , Duruöz Mehmet Tuncay , Aksakalli Elif , Gürgan Alev
Published: May 2016

Objectives

Duruöz Hand Index (DHI) is a functional disability scale that can be used successfully to assess the functional disability with different hand arthropathies. The hands are frequently involved in diabetic patients. We aimed to examine the use of DHI for its accuracy and ease in assessing these patients.

Methods

Forty patients with diabetes mellitus were recruited in this study. Hand pain was assessed with the visual analog scale. Duruöz Hand Index and Hand Functional Index were applied to assess the disability of hand. We evaluated the grip strength and 3 types of pinch strength (tip pinch, lateral or key pinch, and chuck or 3-finger pinch) for the dominant (D) and nondominant (ND) hands of each patient by 2 different kinds of Jamar dynamometers (JA Preston Corp, Jackson, MI).

Results

The Jamar dynamometer scores were as follows (mean [SD]): grip strength-D (21.56 [5.86]), grip strength-ND (16.42 [4.26]), tip strength-D (5.14 [1.50]), tip strength-ND (5.13 [1.42]), lateral strength-D (5.15 [1.52]), lateral strength-ND (5.07 [1.19]), chuck strength-D (5.40 [1.40]), chuck strength-ND (5.33 [1.28]). There was a high correlation between DHI and Hand Functional Index ( P < 0.001, ρ = 0.586) showing that DHI has good convergent validity. The DHI had significant correlation with nonfunctional parameters such as visual analog scale-pain ( P < 0.001), restricted hand motion ( P = 0.020), chuck strength-D ( P = 0.006), pins test-D ( P < 0.001), pins test-ND ( P = 0.013), and assembly test ( P = 0.025).

Conclusions

The DHI is a practical scale that is efficient in accurate assessment of hand dysfunction in diabetic patients.
Allopurinol, Xanthine Oxidase, and Cardiac Ischemia
Authors: Lee Brian E. , Toledo Alexander H. , Anaya-Prado Roberto , Roach Richard R. , Toledo-Pereyra Luis H.
Published: May 2016

Allopurinol as an effective inhibitor of the enzyme xanthine oxidase (XO) has been used for several decades for the treatment of patients with gout and hyperuricemia. Because the inhibition of XO limits the formation of radical oxygen species as well as uric acid (UA) production, allopurinol has been used experimentally for the treatment of conditions associated with ischemia and reperfusion (I/R) injury.

Although there have been many ischemic organs treated in the laboratory with allopurinol, the heart has been of particular interest. Therefore, we emphasize our attention to the administration of XO inhibitors such as allopurinol on cardiac I/R as well as cardiac failure. Experimental data also support allopurinol as a possible consideration for biochemical support after acute myocardial infarction.

Anker and associates ( Circulation. 2003;107:1991-1997) have observed a direct correlation between uric acid levels and mortality in treated heart failure patients. Anker and associates showed a 100% mortality rate in patients with UA levels 800 μmol/L or less over a period of 3 years. Comparing this to a 27% mortality rate in patients with UA levels 400 μmol/L or less over a period of 10 years, it seems that the suppression of XO activity ameliorates myocardial inefficiency, and poor vascular flow may present innovative contributions to the future treatment of I/R heart failure patients. Our review focuses on the role of allopurinol on ischemic hearts as well as those with added chronic heart failure.
Pharmacologic Therapies on the Horizon for Acute Lung Injury/Acute Respiratory Distress Syndrome
Authors: Jacobson Jeffrey R.
Published: May 2016

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) represent a spectrum of diseases that are commonly encountered in the intensive care unit and are associated with high mortality. Although significant advances have been made with respect to the ventilatory management of patients with ALI/ARDS with proven beneficial effects on outcomes, pharmacologic therapies remain nonexistent. Because the cardinal feature of ALI/ARDS is an increase in lung vascular permeability, often precipitated by an exuberant inflammatory response with subsequent endothelial barrier disruption, strategies aimed at promoting endothelial barrier function could serve as novel therapies in this setting. We have identified several promising agonists in this regard including sphingosine 1-phosphate, activated protein C, and statins, a class of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors. These agonists all have in common the ability to directly mediate endothelial cell signaling and induce characteristic actin cytoskeletal rearrangement leading to endothelial cell barrier protection. Our in vitro findings have been extended to animal models of ALI/ARDS and suggest that effective pharmacologic therapies for patients with ALI/ARDS may soon be available.
Vinculin and Talin: Focus on the Myocardium
Authors: Zemljic-Harpf Alice , Manso Ana Maria , Ross Robert S.
Published: May 2016

Cardiomyopathy is a heart muscle disease caused by decreased contractility of the ventricles leading to heart failure and premature death. Multiple conditions like ischemic heart disease (atherosclerosis), hypertension, diabetes, viral infection, alcohol abuse, obesity and genetic mutations can lead to cardiomyopathy. Single gene mutations in sarcomeric proteins, Z-disk-associated proteins, membrane/associated proteins, intermediate filaments, calcium cycle proteins as well as in modifier genes have been linked to cardiomyopathy. Clinical practice guidelines have been formulated by the American Heart Association and the Heart Failure Association of America on how to genetically evaluate patients with cardiomyopathy. To illustrate the concept that alterations in genes cause cardiovascular disease, this review will focus on two membrane-associated proteins, vinculin and talin. We will discuss the general function of vinculin/metavinulin as well as talin1 and talin2, with emphasis on what is understood about their role in the cardiac myocyte and in whole heart.
Integrins, Focal Adhesions, and Cardiac Fibroblasts
Authors: Manso Ana Maria , Kang Seok-Min , Ross Robert S.
Published: May 2016

How the myocardium undergoes geometric, structural, and molecular alterations that result in an end phenotype as might be seen in patients with dilated cardiomyopathy or after myocardial infarction is still poorly understood. Structural modification of the left ventricle, which occurs during these pathological states, results from long-term changes in loading conditions and is commonly referred to as “remodeling.” Remodeling may occur from increased wall stress in the face of hypertensive heart disease, valvular disease, or, perhaps most dramatically, after permanent coronary occlusion. A fundamental derangement of myocyte function is the most common perception for the basis of remodeling, but the role of cells in the heart other than the muscle cell must, of course, be considered. Although studies of the myocyte have been extensive, cardiac fibroblasts have been studied less than myocytes. The fibroblast has a broad range of functions in the myocardium ranging from elaboration and remodeling of the extracellular matrix to communication of a range of signals within the heart, including electrical, chemical, and mechanical ones. Integrins are cell surface receptors that are instrumental in mediating cell-matrix interactions in all cells of the organism, including all types within the myocardium. This review will focus on the role of integrins and related proteins in the remodeling process, with a particular emphasis on the cardiac fibroblast. We will illustrate this function by drawing on 2 unique mouse models with perturbation of proteins linked to integrin function.
Arrhythmogenic Right Ventricular Cardiomyopathy: New Insights into Disease Mechanisms and Diagnosis
Authors: Saffitz Jeffrey E. , Asimaki Angeliki , Huang Hayden
Published: May 2016

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a primary heart muscle disorder characterized by the early occurrence of serious tachyarrhythmias often out of proportion to the extent of structural changes and contractile derangement. Approximately 40% of patients with ARVC have one or more mutations in genes encoding proteins in desmosomes, intercellular adhesion junctions which, in cardiac myocytes, reside within intercalated disks. Some desmosomal proteins fulfill roles both as structural proteins in cell-cell adhesion junctions and as nuclear signaling molecules. It has been proposed that mutations in desmosomal proteins implicated in ARVC may perturb the normal balance of protein in junctions and the cytosol which, in turn, could promote dysregulated gene expression circumventing the normal controls of Wnt signaling pathways. This review highlights recent advances in understanding the pathogenesis of ARVC and presents evidence, suggesting that the disease is caused by a combination of altered cellular biomechanical behavior and altered signaling.
Ezetimibe Effect on Bone Mineral Density and Markers of Bone Formation and Resorption
Authors: Sertbas Yasar , Ersoy Ugur , Ayter Meltem , Gultekin Tırtıl Filiz , Kucukkaya Belgin
Published: May 2016

Background

Ezetimibe, as a lipid-lowering agent, inhibits the intestinal absorption of cholesterol and decreases low-density lipoprotein cholesterol (LDL-C) level in serum. It also up-regulates hepatic cholesterol biosynthesis and, by contrast to statins, increases serum mevalonate levels. Statins and biphosphonates decrease osteoclastic activity through the same mechanisms by inhibiting the mevalonate pathway. We therefore tested the effect of ezetimibe on bone turnover in hypercholesterolemic patients.

Subject and Methods

In an open-label clinical trial, 54 hypercholesterolemic patients included in the study underwent 12 months of treatment with ezetimibe at a dosage of 10 mg/d. Before and after the 1-year ezetimibe treatment, bone mineral density (BMD) was measured by dual-energy x-ray absorptiometry and serum samples taken for measurements of levels of total cholesterol (TC), triglyceride, high-density lipoprotein cholesterol and LDL-C, serum calcium (Ca), serum phosphate, total and bone alkaline phosphatases (ALPs), and carboxyterminal fragment of type 1 collagen in the serum.

Results

The hypercholesterolemic patients showed a significant reduction with respect to baseline TC and LDL-C serum levels: 20% for TC (270.18 [38.58]−214.46 [38] mg/dL) and 24% for LDL-C (189.57 [38.58]−144 [32.05] mg/dL). Biochemical markers of both bone formations (total ALP level, 65.50 [21.33]−66.27 [21.017] IU/L and bone ALP level, 55.93 [7.92]−56.25 [7.49] IU/L) and bone resorption (β-CTx, 0.44 [0.24]−0.46 [0.21] ng/mL) increased but did not show any significant change for the whole study period. At the end of 1 year, both BMD-lumbar spine (0.90 [0.12]−0.89 [0.08] g/cm2) and BMD-total femur (0.93 [0.12]−0.92 [0.12] g/cm2) showed a negative trend but without reaching statistical significance.

Conclusions

Our study results showed a negative trend but did not demonstrate statistically significant changes of BMD and metabolic markers with the treatment of ezetimibe.
Can Teaching Research Methodology Influence Students' Attitude toward Science? Cohort Study and Nonrandomized Trial in a Single Medical School
Authors: Vujaklija Ana , Hren Darko , Sambunjak Dario , Vodopivec Ivana , Ivaniš Ana , Marušić Ana , Marušić Matko
Published: May 2016

Background

Medical teaching aims to develop attitudes and behaviors underlying professional competence of future physicians. We investigated whether a mandatory course on scientific methodology in the second study year could affect students' attitudes toward science in medicine.

Method

In a longitudinal study, students (n = 241) enrolling in 2001-2002 academic year at a single medical school were followed up until graduation in 2006-2007. Each year, they filled out a Likert-type questionnaire of 18 statements evaluating attitude toward science. Direct influence of the course on students' attitudes was tested in a nonrandomized controlled trial with the 2006-2007 second year student cohort.

Results

Positive students' attitudes toward science increased during study years (mean [SD] score of the maximum score of 90): from 57.6 (6.0) in the first to 69.8 (10.4) in the sixth year. There was a significant trend of increase in attitudes with the years of study (cubic trend by polynomial contrasts analysis, P = 0.011). Attendance of a course on research methodology significantly increased positive attitudes (score, 67.0 [7.0] before and 70.8 [7.5] after course, P = 0.032 vs control group), regardless of grade point average. The intervention had an effect even when the influence of the initial attitude was accounted for (F1,140 = 9.25, P = 0.003; analysis of covariance). The attitude changes after the course was greatest in students with low initial attitude scores (Spearman rinitial score, score difference, −0.44).

Conclusions

Medical students have positive attitudes toward science and scientific method in medicine. Attendance of a course on research methodology had positive short-term effect on students' attitudes toward science. This positive effect should be maintained by vertical integration of the course in the medical curriculum.
Phenomics: Expanding the Role of Clinical Evaluation in Genomic Studies
Authors: Lanktree Matthew B. , Hassell Reina G. , Lahiry Piya , Hegele Robert A.
Published: May 2016

With advances in high-throughput genotyping technologies, the rate-limiting step of large-scale genetic investigations has become the collection of sensitive and specific phenotype information in large samples of study participants. Clinicians play a pivotal role for successful genetic studies because sound clinical acumen can substantially increase study power by reducing measurement error and improving diagnostic precision for translational research. Phenomics is the systematic measurement and analysis of qualitative and quantitative traits, including clinical, biochemical, and imaging methods, for the refinement and characterization of a phenotype. Phenomics requires deep phenotyping, the collection of a wide breadth of phenotypes with fine resolution, and phenomic analysis, composed of constructing heat maps, cluster analysis, text mining, and pathway analysis. In this article, we review the components of phenomics and provide examples of their application to genomic studies, specifically for implicating novel disease processes, reducing sample heterogeneity, hypothesis generation, integration of multiple types of data, and as an extension of Mendelian randomization studies.
Regulation of Neutrophil Elastase-Induced MUC5AC Expression by Nuclear Factor Erythroid-2 Related Factor 2 in Human Airway Epithelial Cells
Authors: Qi Li , Xiangdong Zhou , Hongmei Yu , Xiaohong Nie , Xiaoyan Xu
Published: May 2016

Mucin 5AC ( MUC5AC) is one of the main airway mucins implicated in pulmonary diseases with mucous hypersecretion. Neutrophil elastase (NE), a serine protease released by neutrophils, is known to induce MUC5AC synthesis by increasing reactive oxygen species (ROS) generation. Nuclear factor erythroid-2 related factor 2 (Nrf2), a basic-region leucine-zipper transcription factor, is believed to protect against ROS damage by activating a series of antioxidant enzymes; Nrf2 is also reported to reduce NE activity. The aim of our study was to examine the relationship between Nrf2 expression and NE-induced MUC5AC production. We used a small interfering RNA to inhibit Nrf2 expression. The Nrf2 gene and protein expressions were assessed by quantitative real-time polymerase chain reaction, and Western blotting, respectively. The ROS generation was examined using a kit. The expression of MUC5AC was assessed using enzyme-linked immunosorbent assay. The results showed that NCI-H292 epithelial cells, in which the Nrf2 gene expression repressed, were highly predisposed to NE stimulation, with marked exacerbation of ROS generation and reduced secretory leukocyte protease inhibitor production, resulting in high MUC5AC expression. Pretreatment with the potent Nrf2 activator sulforaphane had the reverse effect. These results demonstrate that Nrf2 is a novel nuclear factor involved in down-regulating MUC5AC synthesis by inhibiting ROS generation and augmenting proteinase inhibitor production.
Exchanging Carbohydrate or Protein for Fat Improves Lipid-Related Cardiovascular Risk Profile in Overweight Men and Women When Consumed Ad Libitum
Authors: Kratz Mario , Weigle David S. , Breen Patricia A. , Meeuws Kaatje E. , Burden Verna R. , Callahan Holly S. , Matthys Colleen C. , Purnell Jonathan Q.
Published: May 2016

Background

The impact of low-fat diets on the plasma lipoprotein profile is incompletely understood.

Methods

We conducted two 16-week dietary studies to compare the effects of a moderate-fat (mod-FAT) baseline diet with isocaloric and ad libitum low-fat diets rich in either carbohydrates (high-CHO, n = 16) or protein (high-PRO, n = 19) on plasma lipids, post-heparin lipase activities, cholesteryl ester transfer protein, and phospholipid transfer protein.

Results

Switching from the mod-FAT to the isocaloric high-CHO diet lowered plasma high-density lipoprotein cholesterol concentrations ( P < 0.001) and tended to increase triglyceride levels ( P = 0.087). Cholesterol content in the larger, buoyant low-density lipoprotein (LDL) fractions decreased, whereas those of the very-low-density lipoprotein, intermediate-density lipoprotein, and smaller, denser LDL fractions tended to increase. These changes were largely reversed when subjects lost weight by consuming this high-CHO diet ad libitum. Switching from the mod-FAT diet to the isocaloric high-PRO diet did not increase cholesterol content in the small-dense LDL fraction and led to decreases in both LDL and high-density lipoprotein cholesterol in plasma ( P < 0.001 for both). Consumption of the high-protein ad libitum diet accompanied by weight loss did not change plasma lipids further, except for a shift of cholesterol from dense low-density lipoprotein fractions to more buoyant low-density lipoprotein fractions. Cholesteryl ester transfer protein concentrations decreased with high-cholesterol feeding, whereas cholesteryl ester transfer protein concentrations and hepatic lipase and phospholipid transfer protein activities all decreased during high-protein feeding.

Conclusions

Both high-CHO and high-PRO diets improve plasma lipid-related risk of cardiovascular disease when consumed ad libitum.
A Novel Missense Mutation in Cathepsin K (CTSK) Gene in a Consanguineous Pakistani Family with Pycnodysostosis
Authors: Khan Bushra , Ahmed Zahoor , Ahmad Wasim
Published: May 2016

Background

Deficiency of cathepsin K ( CTSK), a lysosomal cysteine protease, has been shown earlier as a cause of an autosomal recessive osteosclerotic skeletal dysplasia pycnodysostosis. The objective of the present study was to identify the potential sequence variants in CTSK gene in a large consanguineous Pakistani family with pycnodysostosis.

Methods

Genotyping of 4 affected and 6 unaffected members of the family was performed using polymorphic microsatellite markers linked to CTSK gene on chromosome 1q21. To screen for pathogenic mutation, exons and splice junctions of CTSK gene were polymerase chain reaction amplified from genomic DNA and sequenced directly in an automated DNA sequencer.

Results

Microsatellite analysis showed linkage of the family to CTSK gene on chromosome 1q21. Sequence analysis revealed a novel missense mutation c.728G>A (p.G243E) in exon 6 of the CTSK gene.

Conclusions

A novel missense mutation was identified in CTSK gene in a Pakistani family with 5 individuals affected with autosomal recessive pycnodysostosis
Acetaminophen Dose Does Not Predict Outcome in Acetaminophen-Induced Acute Liver Failure
Authors:   The Acute Liver Failure Study Group, Gregory Blake , Larson Anne M. , Reisch Joan , Lee William M.
Published: May 2016

Background

Acetaminophen is a dose-dependent toxin. Prognosis in severe acute liver injury is related presumably in part to the dose ingested. We sought to assess the value of acetaminophen dosing information in patients with acute liver failure (ALF) due to acetaminophen toxicity to determine the role of dose as a prognostic indicator.

Methods

Prospective data from 113 patients with ALF having single-time-point ingestions of acetaminophen were analyzed. Multivariate and χ2 tests were used to determine the relationship of dose to clinical outcome. We also used the Mann-Whitney U test to compare prognosis and survival in ALF with acetaminophen dose ingested.

Results

Multivariate and χ2 analyses failed to show any relationship between acetaminophen dose and spontaneous survival. A separate analysis showed no correlation between acetaminophen dose and clinical prognostic indicators.

Conclusions

Dose of acetaminophen ingested did not seem to play a role in prognosis. The most important prognostic factor was coma grade on admission to study. Acetaminophen dosing information is not always obtainable. When it is, it adds little to the clinical assessment. Severity of encephalopathy is a more reliable indicator of prognosis in these critically ill patients.
Comparative Effectiveness Research: What Kind of Studies Do We Need?
Authors: Concato John , Peduzzi Peter , Huang Grant D. , O'Leary Timothy J. , Kupersmith Joel
Published: May 2016

Comparative effectiveness research (CER) is increasingly popular, yet discussions of its conduct and consequences often overlook the extensive history of comparing different therapeutic options in patient-oriented research. In particular, research in the Department of Veterans Affairs (VA) has included a decades-long focus on generating information that can enhance medical decision making and improve health outcomes. Categories of such research include multisite randomized controlled trials (conducted by the Cooperative Studies Program) and observational studies involving either primary or secondary data collection. As representative examples from cardiology, a landmark VA clinical trial published in the 1970s evaluated the benefits of coronary artery bypass grafting surgery among patients with angina; a VA trial initiated in the 1990s, and identified formally as CER, demonstrated that percutaneous coronary intervention is not superior to optimal medical therapy; and a database investigation using information from the VA electronic medical record system in the 2000s found that use of proton pump inhibitor medication is associated with the attenuation of the benefits of clopidogrel among patients hospitalized for acute coronary syndrome. A review of these (and other) selected projects, based on their type of study design, serves to highlight the strengths, limitations, and potential of CER.