Differential evolution of peripheral cytokine levels in symptomatic and asymptomatic responses to experimental influenza virus challenge.

Exposure to influenza virus triggers a complex cascade of events in the human host. In order to understand more clearly the evolution of this intricate response over time, human volunteers were inoculated with influenza A/Wisconsin/67/2005 (H3N2), and then had serial peripheral blood samples drawn and tested for the presence of 25 major human cytokines. Nine of 17 (53%) inoculated subjects developed symptomatic influenza infection. Individuals who will go on to become symptomatic demonstrate increased circulating levels of interleukin (IL)-6, IL-8, IL-15, monocyte chemotactic protein (MCP)-1 and interferon (IFN) gamma-induced protein (IP)-10 as early as 12-29 h post-inoculation (during the presymptomatic phase), whereas challenged patients who remain asymptomatic do not. Overall, the immunological pathways of leucocyte recruitment, Toll-like receptor (TLR)-signalling, innate anti-viral immunity and fever production are all over-represented in symptomatic individuals very early in disease, but are also dynamic and evolve continuously over time. Comparison with simultaneous peripheral blood genomics demonstrates that some inflammatory mediators (MCP-1, IP-10, IL-15) are being expressed actively in circulating cells, while others (IL-6, IL-8, IFN-α and IFN-γ) are probable effectors produced locally at the site of infection. Interestingly, asymptomatic exposed subjects are not quiescent either immunologically or genomically, but instead exhibit early and persistent down-regulation of important inflammatory mediators in the periphery. The host inflammatory response to influenza infection is variable but robust, and evolves over time. These results offer critical insight into pathways driving influenza-related symptomatology and offer the potential to contribute to early detection and differentiation of infected hosts.

Primary care physicians' knowledge of and experience with pharmacogenetic testing.

It is anticipated that as the range of drugs for which pharmacogenetic testing becomes available expands, primary care physicians (PCPs) will become major users of these tests. To assess their training, familiarity, and attitudes toward pharmacogenetic testing in order to identify barriers to uptake that may be addressed at this early stage of test use, we conducted a national survey of a sample of PCPs. Respondents were mostly white (79%), based primarily in community-based primary care (81%) and almost evenly divided between family medicine and internal medicine. The majority of respondents had heard of PGx testing and anticipated that these tests are or would soon become a valuable tool to inform drug response. However, only a minority of respondents (13%) indicated they felt comfortable ordering PGx tests and almost a quarter reported not having any education about pharmacogenetics. Our results indicate that primary care practitioners envision a major role for themselves in the delivery of PGx testing but recognize their lack of adequate knowledge and experience about these tests. Development of effective tools for guiding PCPs in the use of PGx tests should be a high priority.

The oral microbiome in health and disease and the potential impact on personalized dental medicine.

Every human body contains a personalized microbiome that is essential to maintaining health but capable of eliciting disease. The oral microbiome is particularly imperative to health because it can cause both oral and systemic disease. The oral microbiome rests within biofilms throughout the oral cavity, forming an ecosystem that maintains health when in equilibrium. However, certain ecological shifts in the microbiome allow pathogens to manifest and cause disease. Severe forms of oral disease may result in systemic disease at different body sites. Microbiomics and metagenomics are two fields of research that have emerged to identify the presence of specific microbes in the body and understand the nature of the microbiome activity during both health and disease. The analysis of the microbiome and its genomes will pave the way for more effective therapeutic and diagnostic techniques and, ultimately, contribute to the development of personalized medicine and personalized dental medicine.

Genome technologies and personalized dental medicine.

The addition of genomic information to our understanding of oral disease is driving important changes in oral health care. It is anticipated that genome-derived information will promote a deeper understanding of disease etiology and permit earlier diagnosis, allowing for preventative measures prior to disease onset rather than treatment that attempts to repair the diseased state. Advances in genome technologies have fueled expectations for this proactive healthcare approach. Application of genomic testing is expanding and has already begun to find its way into the practice of clinical dentistry. To take full advantage of the information and technologies currently available, it is vital that dental care providers, consumers, and policymakers be aware of genomic approaches to understanding of oral diseases and the application of genomic testing to disease diagnosis and treatment. Ethical, legal, clinical, and educational initiatives are also required to responsibly incorporate genomic information into the practice of dentistry. This article provides an overview of the application of genomic technologies to oral health care and introduces issues that require consideration if we are to realize the full potential of genomics to enable the practice of personalized dental medicine.

Intestinal apolipoprotein AI gene transcription is regulated by multiple distinct DNA elements and is synergistically activated by the orphan nuclear receptor, hepatocyte nuclear factor 4.

We have used apolipoprotein genes to investigate the signal transduction mechanisms involved in the control of intestinal specific gene expression. The human apoAI, apoCIII, and apoAIV genes are tandemly organized within a 15-kb DNA segment and are expressed predominantly in the liver and intestine. Transient transfection of various human apoAI gene plasmid constructs into human hepatoma (HepG2) and colon carcinoma (Caco-2) cells showed that apoAI gene transcription is under the control of two separate and distinct cell-specific promoters. The region between nucleotides -192 and -41 is essential for expression in HepG2 cells, whereas the region from -595 to -192 is essential for expression in Caco-2 cells. A third 0.6 kb DNA fragment in the apoCIII gene promoter region, approximately 5 kb down-stream from the human apoAI gene, enhances transcription mediated by either of these two tissue-specific apoAI promoters. In Caco-2 cells, expression of the apoAI gene and activation by the distal enhancer required the presence of a nuclear hormone receptor response element (NHRRE) located in the -214 to -192 apoAI promoter region. Overexpression of the orphan receptor hepatocyte nuclear factor 4 (HNF-4), which binds to the NHRRE, dramatically stimulates apoAI gene expression in Caco-2 cells but not in HepG2 cells. Maximal stimulation of transcription by HNF-4 in Caco-2 cells required the presence of both the intestinal specific promoter, the NHRRE, and distal enhancer elements. Transactivation by HNF-4 thus appears to result from functional synergy between the NHRRE binding HNF-4 and distal DNA elements containing intestinal-specific DNA binding activities. The apoAI gene provides a model system to define the mechanism(s) governing intestinal cell specific gene regulation and the role of nuclear hormone receptors in the establishment and regulation of enterocytic gene transcription.

Intestinal transcription and synthesis of apolipoprotein AI is regulated by five natural polymorphisms upstream of the apolipoprotein CIII gene.

To understand the factors contributing to the synthesis of human apolipoprotein AI (apoAI), relative apoAI synthesis was measured from endoscopic biopsy samples obtained from 18 healthy volunteers. The relative amount of apoAI synthesis was directly correlated with steady state intestinal apoAI mRNA levels and a 10-fold within-group variability was observed. Analysis of genomic DNA from the subjects revealed five polymorphic sites which defined two haplotypes in the intestinal enhancer region of the apoAI gene located upstream of the apolipoprotein CIII gene transcriptional start site (+ 1): (-641 C to A, -630 G to A, -625 T to deletion, -482 C to T, and -455 T to C). The population frequencies of the wild-type and mutant alleles were 0.53 and 0.44, respectively. Mean steady state apoAI mRNA levels and mean relative apoAI synthesis were 49 and 37% lower, respectively, in homozygotes for the mutant allele and 28 and 41% lower, respectively, in heterozygotes than in homozygotes for the wild-type allele (P < 0.05 for both). Site-directed mutants of apoAI gene promoter/reporter constructs containing the above mutations were transfected into Caco-2 cells and showed a 46% decrease in transcriptional activity compared with the wild type (P < 0.001); however, no significant differences were observed in HepG2 cells. Electrophoretic mobility shift assays showed that the mutated sequences from -655 to -610 bound Caco-2 cell nuclear protein(s) while the wild type did not. These results indicate that intestinal apoAI gene transcription and protein synthesis are genetically determined and are reduced in the presence of common mutations which induced binding of nuclear protein(s), possibly a transcriptional repressor.

Antagonism between apolipoprotein AI regulatory protein 1, Ear3/COUP-TF, and hepatocyte nuclear factor 4 modulates apolipoprotein CIII gene expression in liver and intestinal cells.

Apolipoprotein CIII (apoCIII), a lipid-binding protein involved in the transport of triglycerides and cholesterol in the plasma, is synthesized primarily in the liver and the intestine. A cis-acting regulatory element, C3P, located at -90 to -66 upstream from the apoCIII gene transcriptional start site (+1), is necessary for maximal expression of the apoCIII gene in human hepatoma (HepG2) and intestinal carcinoma (Caco2) cells. This report shows that three members of the steroid receptor superfamily of transcription factors, hepatocyte nuclear factor 4 (HNF-4), apolipoprotein AI regulatory protein 1 (ARP-1), and Ear3/COUP-TF, act at the C3P site. HNF-4 activates apoCIII gene expression in HepG2 and Caco2 cells, while ARP-1 and Ear3/COUP-TF repress its expression in the same cells. HNF-4 activation is abolished by increasing amounts of ARP-1 or Ear3/COUP-TF, and repression by ARP-1 or Ear3/COUP-TF is alleviated by increasing amounts of HNF-4. HNF-4 and ARP-1 bind with similar affinities to the C3P site, suggesting that their opposing transcriptional effects may be mediated by direct competition for DNA binding. HNF-4 and ARP-1 mRNAs are present within the same cells in the liver and intestine, and protein extracts from hepatic tissue, HepG2, and Caco2 cells contain significantly more HNF-4 than ARP-1 or Ear3/COUP-TF binding activities. These findings suggest that the transcription of the apoCIII gene in vivo is dependent, at least in part, upon the intracellular balance of these positive and negative regulatory factors.

Physical properties of cholesteryl esters.

Cholesteryl esters, the intracellular storage form and intravascular transport form of cholesterol, can exist in crystal, liquid crystal and liquid states. The physical state of cholesteryl esters at physiologic temperatures may be a determinant of their pathogenicity. This review has surveyed saturated aliphatic cholesteryl esters of chain length 1 to 24 carbons and a series of medium-chained unsaturated cholesteryl esters from chain lengths 14 to 24 carbons. A systematic study of transition temperatures by polarizing microscopy and enthalpies by differential scanning calorimetry has provided unifying concepts concerning the phase behavior as a function of chain length and unsaturation. Neat cholesteryl esters show chain-length dependence of transition temperature and enthalpy of both the crystal and liquid crystal transitions. Double bond position along the fatty acyl chain affected stability of the liquid crystal phases; a smectic phase was not observed for any cholesteryl ester with a double bond more proximal than delta 9. 13C NMR spectroscopy in the isotropic liquid phase has provided evidence suggesting a balance of ring-ring vs. chain-chain interactions as a determinant for isotropic liquid----cholesteric vs. isotropic liquid----smectic transitions. Specifically, anisotropic molecular motions of the steroid ring are greater for cholesteryl esters forming a cholesteric phase than a smectic phase from the melt. Chain-chain interactions apparently predominate in smectic phase formation. The X-ray diffraction patterns of cholesteryl esters as a function of chain length reveal several isostructural series and known single crystal data are presented. A chain length depending on the periodicity of the smectic phase is observed which may be different for saturated vs. unsaturated esters. In summary, the phase behavior of cholesteryl ester molecules is complex and cannot be determined a priori from the phase behavior of component cholesterol and fatty acid. The data presented here should provide insight into the biological behavior of this lipid class.

Physical properties of cholesteryl esters having 20 carbons or more.

By polarizing microscopy and differential scanning calorimetry we observed that the relative stability of the smectic and cholesteric mesophases of cholesteryl esters of acyl chain length of 20 carbons or more depends on the length of the acyl chain and its degree of unsaturation. Significantly, the addition of a single double bond to the acyl chain of a fully saturated cholesteryl ester which exhibits no mesophases (e.g., cholesteryl behenate (C22:0) and cholesteryl lignocerate (C24:0) yields an ester which displays an unusually stable smectic mesophase, bot no cholesteric mesophase. In fact, increasing unsaturation was found to have a destabilizing effect on the cholesteric phase. Similarly, a decrease in thermal stability of the cholesteric mesophase was observed with increasing thermal stability of the smectic mesophase increased in the same series. X-ray scattering data are presented on the smectic mesophase of cholesteryl erucate (C22:1) and cholesteryl nervonate (C24:1). Significant differences in molecular packing of these two monounsaturated omega = 9 cholesteryl esters in the crystalline state are demonstrated by preliminary X-ray scattering experiments.

Personalized medicine: revolutionizing drug discovery and patient care.

Advances in human genome research are opening the door to a new paradigm for practising medicine that promises to transform healthcare. Personalized medicine, the use of marker-assisted diagnosis and targeted therapies derived from an individual's molecular profile, will impact the way drugs are developed and medicine is practiced. Knowledge of the molecular basis of disease will lead to novel target identification, toxicogenomic markers to screen compounds and improved selection of clinical trial patients, which will fundamentally change the pharmaceutical industry. The traditional linear process of drug discovery and development will be replaced by an integrated and heuristic approach. In addition, patient care will be revolutionized through the use of novel molecular predisposition, screening, diagnostic, prognostic, pharmacogenomic and monitoring markers. Although numerous challenges will need to be met to make personalized medicine a reality, with time, this approach will replace the traditional trial-and-error practice of medicine.

The treatment of anxiety disorders in children and adolescents.

Anxiety disorders are the most common psychiatric conditions in the pediatric population, with prevalence estimates ranging from 5-18%. Children and adolescents with excessive anxiety often meet diagnostic criteria for a number of disorders within the DSM-IV. Unfortunately, the current diagnostic system is controversial because of high rates of symptom overlap, comorbidity with other psychiatric disorders, and lack of biological markers that would support a more empirical anxiety nosology. Treatment strategies for pediatric anxiety disorders have important historical roots. Several controlled studies of cognitive-behavioral therapy (CBT) demonstrate efficacy for pediatric anxiety disorders. In contrast, no controlled psychopharmacology studies have demonstrated efficacy in children and adolescents with anxiety disorders, except obsessive-compulsive disorder; however, several large, methodologically sound psychopharmacotherapy trials are underway for pediatric anxiety disorders. This update will review the current status of psychosocial and psychopharmacologic treatment of pediatric anxiety disorders. In addition, a brief discussion of nosology, epidemiology, and developmental course of anxiety is included. Preliminary psychopharmacology treatment and CBT treatment algorithms are presented for pediatric anxiety disorders, based on the best available data. Recommendations for future research directions are also discussed.

High-density lipoprotein subfractions.

High-density lipoprotein (HDL) consists of a heterogeneous group of particles defined either by size or by apolipoprotein content. Subfractions of HDL appear to have distinct but interrelated metabolic functions, including facilitation of cholesteryl ester transfer to low- and very-low-density lipoproteins, modulation of triglyceride-rich particle catabolism, and, possibly, removal of cholesterol from peripheral tissues. Like HDL cholesterol, HDL subfractions are widely affected by a variety of factors. Subfractions also are markers for epidemiologic risk for coronary artery disease. Because they provide information about the physiologic processes of cholesterol metabolism, HDL subfractions are emerging as an increasingly important tool in the study of the relationship between lipids and cardiovascular disease.

Frequency of low serum high-density lipoprotein cholesterol levels in hospitalized patients with "desirable" total cholesterol levels.

Because the National Cholesterol Education Program guidelines suggest that levels of total serum cholesterol less than 5.17 mmol/liter (200 mg/dl) are "desirable," we performed a retrospective observational analysis to determine the prevalence of coronary artery disease (CAD) in patients with total cholesterol less than 5.17 mmol/liter (200 mg/dl) and the prevalence of total cholesterol less than 5.17 mmol/liter (200 mg/dl) in patients with CAD by angiography. Cholesterol levels less than 5.17 mmol/liter (200 mg/dl) were found in 1,084 of 2,535 patients (42%) having cholesterol measured on hospital admission; 690 of these 1,084 (64%) had CAD. These patients were mostly men, had a family history of premature CAD, and 60% (414 of 690) had high-density lipoprotein (HDL) cholesterol less than 0.90 mmol/liter (35 mg/dl). In a separate group of patients defined from the same admission population but having angiographically established CAD, 32% (424 of 1,197) had a total cholesterol less than 5.17 mmol/liter (200 mg/dl), 59% of whom (252 of 424) had HDL less than 0.90 mmol/liter (35 mg/dl). An analysis of persons admitted electively for angiography (to exclude any effects of hospitalization per se on serum lipids) revealed a similar proportion of persons with total cholesterol less than 5.17 mmol/liter (200 mg/dl) (35%), CAD (82%), and HDL less than 0.90 mmol/liter (35 mg/dl).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of heparin and cardiac catheterization on serum lipoprotein and triglyceride levels.

This study determined whether heparin administration and procedures involving heparin significantly affect lipid measurement. Serum lipid and lipoprotein analyses (total cholesterol, triglycerides, high-density lipoprotein [HDL] cholesterol, low-density lipoprotein [LDL] cholesterol, apolipoprotein B, and apolipoprotein A-I) were performed at baseline and at several time points after (1) intravenous heparin or placebo in 6 healthy volunteers (group 1), (2) cardiac catheterization with heparin in 26 patients (group 2), and (3) peripheral angiography without heparin in 11 patients (group 3). In group 1, after heparinization, triglycerides decreased 50 +/- 12 mg/dl (-57%, p < 0.001 vs baseline and placebo) at 60 minutes. No changes were observed in other lipid or lipoprotein fractions. After cardiac catheterization (group 2), however, decreases were observed not only in triglycerides (58 +/- 26 mg/dl [-40%]), but also in total cholesterol (28 +/- 12 mg/dl [-14%]), LDL cholesterol (19 +/- 22 mg/dl [-15%]), apolipoprotein B (13 +/- 9 mg/dl [-14%]), and apolipoprotein A-I (21 +/- 14 mg/dl [-17%]) (p < 0.001 vs baseline for all), and HDL cholesterol (4 +/- 7 mg/dl [-3%], p = 0.07). With the exception of triglycerides, these values remained significantly decreased for > or = 24 hours. The change in HDL was variable: Whereas most patients had a decrease (n = 24), 2 patients had a dramatic increase (> 100%) after administration of heparin. Similar decreases in total cholesterol, LDL cholesterol, and apolipoproteins B and A-I were observed in group 3 undergoing peripheral angiography without heparin.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation and clinical application of a direct low-density lipoprotein cholesterol assay in normolipidemic and hyperlipidemic adults.

This study examines the performance and clinical use of a commercial immunoseparation assay for low-density lipoprotein (LDL) cholesterol in a sample population of normolipidemic and hyperlipidemic adult volunteers. Using paired fasting and nonfasting samples, we compared the direct LDL assay with the beta quantification method and the Friedewald calculation. Overall, the direct LDL assay correctly classified 82% and 60% of fasting and nonfasting subjects, respectively, into National Cholesterol Education Program risk groups. The Friedewald method correctly classified 84% of subjects. The fasting direct LDL assay has comparable positive and negative predictive values to the Friedewald method, except at an LDL cholesterol of 100 mg/dl. The nonfasting direct LDL assay demonstrates unacceptable positive predictive values when LDL cholesterol decreases to the 130 to 159 and > or = 160 mg/dl categories. Overall, direct LDL assay demonstrates limitations in the nonfasting state and at the LDL cholesterol level of 100 mg/dl used for patients with established coronary heart disease.

Cardiac troponin T and I, echocardiographic [correction of electrocardiographic] wall motion analyses, and ejection fractions in athletes participating in the Hawaii Ironman Triathlon.

Cardiac troponin T (cTnT) and troponin I (cTnI) are highly sensitive and specific for detecting myocardial damage even in the presence of skeletal muscle injury. In this study, we assessed whether ultraendurance exercise induced cardiomyocyte injury using plasma cTnT and cTnI measurements, quantitative echocardiographic wall-motion analysis, and ejection fraction measurement in athletes who participated in the Hawaii Ironman Triathlon. Twenty-three athletes (11 men) who completed the triathlon (3.9 km swim, 180.2 km bike, and 42.2 km run) participated in this study. Blood samples were obtained 2 days before and immediately after the triathlon for the determination of cTnT (Enzymun, Roche Diagnostics) and cTnI (Dade Behring) concentrations. Quantitative echocardiographic wall motion analysis and ejection fraction were obtained on 12 of the 23 participants before and immediately after the race. No subject had detectable cTnT or cTnI or abnormal echo score before the race. Following the race, 2 subjects (9%) had marked increases in both cTnT (0.15 and 0.33 microg/L) and cTnI (2.09 and 4.44 microg/L). Four additional subjects (17%) had moderate increases in cTnT (0.04 to 0.05 microg/L) but no detectable cTnI. Race time correlated inversely with cTnT (r = -0.65, p <0.01). Mean change in the number of abnormal echo segments after the race was 6.5 in those with a marked increase in cTnT and cTnI, 2.3 in those with a moderate increase in cTnT, and 1.7 in those with no increase. Ejection fraction decreased by an average of 24% after the race (p <0.002). Thus, ultraendurance exercise may cause myocardial damage as indicated by biochemical cardiac-specific markers and echocardiography. The cellular nature of this damage and whether it is transient or permanent is unclear at present.

Left ventricular hypertrophy in athletes.

Left ventricular wall thickness >1.3 cm, septal-to-posterior wall ratios > 1.5, diastolic left ventricular size >6.0 cm, and eccentric or concentric remodeling are rare in athletes. Values outside of these cutoffs in an athlete of any age probably represent a pathologic state.

Novel missense mutation in the cyclic nucleotide-binding domain of HERG causes long QT syndrome.

Autosomal-dominant long QT syndrome (LQT) is an inherited disorder, predisposing affected individuals to sudden death from tachyarrhythmias. To identify the gene(s) responsible for LQT, we identified and characterized an LQT family consisting of 48 individuals. DNA was screened with 150 microsatellite polymorphic markers encompassing approximately 70% of the genome. We found evidence for linkage of the LQT phenotype to chromosome 7(q35-36). Marker D7S636 yielded a maximum lod score of 6.93 at a recombination fraction (theta) of 0.00. Haplotype analysis further localized the LQT gene within a 6.2-cM interval. HERG encodes a potassium channel which has been mapped to this region. Single-strand conformational polymorphism analyses demonstrated aberrant bands that were unique to all affected individuals. DNA sequencing of the aberrant bands demonstrated a G to A substitution in all affected patients; this point mutation results in the substitution of a highly conserved valine residue with a methionine (V822M) in the cyclic nucleotide-binding domain of this potassium channel. The cosegregation of this distinct mutation with LQT demonstrates that HERG is the LQT gene in this pedigree. Furthermore, the location and character of this mutation suggests that the cyclic nucleotide-binding domain of the potassium channel encoded by HERG plays an important role in normal cardiac repolarization and may decrease susceptibility to ventricular tachyarrhythmias.

Atherosclerosis: a cancer of the blood vessels?

A series of molecular pathways have in common a significant role in the pathogenesis and progression of atherosclerosis and cancer. Shared mechanisms implicated for both diseases include oxidative stress and the cellular damage that results from it, toxic metabolites produced by cigarette smoking, and increased dietary fat intake. Atherosclerosis may begin when an injury or infection mutates or transforms a single arterial smooth muscle cell in the progenitor of a proliferative clone, similar to the most widely held carcinogenesis theory. Cell proliferation regulatory pathways have been associated with plaque progression, stenosis, and restenosis after angioplasty and with cancer progression. Alterations in cell adhesion molecules have been linked to plaque formation and thrombosis and to tumor invasion and metastasis. Altered expression of proteases associated with thrombolysis has been implicated in atherosclerotic plaque expansion and hemorrhage and in the invasion and metastasis of malignant neoplasms. Ligand-growth factor receptor interactions have been associated with early atherosclerotic lesions and with cancer development and spread. Nuclear transcription factors have been associated with progression of both diseases. Angiogenesis modulators have been linked to plaque expansion and restenosis of atherosclerotic lesions and to local and metastatic tumor expansion.