CYCLOIDEA paralogs function partially redundantly to specify dorsal flower development in Mimulus lewisii.

PREMISE: Duplicated genes (paralogs) are abundant in plant genomes, and their retention may influence the function of genetic programs and contribute to evolutionary novelty. How gene duplication affects genetic modules and what forces contribute to paralog retention are outstanding questions. The CYCLOIDEA(CYC)-dependent flower symmetry program is a model for understanding the evolution of gene duplication, providing multiple examples of paralog partitioning and novelty. However, a novel CYC gene lineage duplication event near the origin of higher core Lamiales (HCL) has received little attention. METHODS: To understand the evolutionary fate of duplicated HCL CYC2 genes, we determined the effects on flower symmetry by suppressing MlCYC2A and MlCYC2B expression using RNA interference (RNAi). We determined the phenotypic effects on flower symmetry in single- and double-silenced backgrounds and coupled our functional analyses with expression surveys of MlCYC2A, MlCYC2B, and a putative downstream RADIALIS (MlRAD5) ortholog. RESULTS: MlCYC2A and MlCYC2B jointly contribute to bilateral flower symmetry. MlCYC2B exhibits a clear dorsal flower identity function and may additionally function in carpel development. MlCYC2A functions in establishing dorsal petal shape. Further, our results suggest an MlCYC2A-MlCYC2B regulatory interaction, which may affect pathway homeostasis. CONCLUSIONS: Our results suggest that CYC paralogs specific to higher core Lamiales may be selectively retained for their joint contribution to bilateral flower symmetry, similar to the independently derived CYC paralogs in the Lamiales model for bilateral flower symmetry research, Antirrhinum majus (snapdragon).

Delayed type hypersensitivity-induced myeloid-derived suppressor cells regulate autoreactive T cells.

Mild but efficient treatments of autoimmune diseases are urgently required. One such therapy, long-term maintenance of chronic delayed type hypersensitivity, has been described for alopecia areata (AA), a hair follicle-affecting autoimmune disease. The molecular mechanisms underlying the therapeutic efficacy are unknown, but may involve myeloid-derived suppressor cells (MDSCs). AA-affected mice were treated with squaric acid dibutyl ester (SADBE). The immunoreactivity of SADBE-treated AA lymphocytes and of AA lymphocytes co-cultured with SADBE-induced MDSCs was analyzed. The curative effect of SADBE was abolished by all-transretinoic acid, which drives MDSCs into differentiation, confirming a central role for MDSCs in therapeutic SADBE treatment. SADBE and SADBE-induced MDSCs strongly interfered with sustained autoreactive T-cell proliferation in response to AA skin lysate (autoantigen), which was accompanied by weak ζ-chain down-regulation and strongly impaired Lck activation. In contrast, activation of the mitochondrial apoptosis pathway and blockade of the anti-apoptotic PI3K/Akt pathway by SADBE-induced MDSCs did not require T-cell receptor engagement. Apoptosis induction correlated with high TNF-α expression in SADBE-induced MDSCs and elevated TNFRI levels in AA lymphocytes. SADBE-induced MDSCs interfere with persisting autoreactive T-cell proliferation and promote apoptosis of these T cells, which qualifies MDSCs induced and maintained by chronic delayed type hypersensitivity reactions as promising therapeutics in organ-related autoimmune diseases.

Lymphopenia and DMTs for relapsing forms of MS: Considerations for the treating neurologist.

PURPOSE OF REVIEW: To provide neurologists with an update on the proposed mechanisms of action (MOAs) of disease-modifying therapies (DMTs) for the treatment of relapsing MS, and their effect on peripheral blood leukocytes, in order to inform treatment decisions. RECENT FINDINGS: DMTs have vastly differing MOAs, including effects on peripheral blood leukocyte counts, particularly lymphocytes. The clinical implications of changes in lymphocyte counts need to be understood in the context of the underlying MOAs of each respective DMT, with treatment tailored to individual patient needs. SUMMARY: DMTs can alter lymphocyte counts, subsets, activation, and distribution, and thus can influence immune surveillance. Serial monitoring of total leukocytes and absolute lymphocyte counts (ALCs) is advisable in patients receiving DMTs. ALCs should be interpreted regarding expected immunologic changes and individual patient characteristics. Any decision to switch DMTs should consider these factors, along with drug efficacy, safety, and effect on quality of life.

Reducing the burden of coronary artery disease in India: challenges and opportunities.

UNLABELLED: Asian Indians--living both in India and abroad--have one of the highest rates of coronary artery disease (CAD) in the world, three times higher than the rates among Caucasians in the United States. The CAD among Indians is usually more aggressive at the time of presentation compared with whites or East Asians. The overall impact is much greater because the CAD in Asian Indians affects the "younger" working population. This kind of disproportionate epidemic among the young Indians is causing tremendous number of work days lost at a time when India is experiencing a dizzying economic boom and needs a healthy populace to sustain this boom. While the mortality and morbidity from CAD has been falling in the western world, it has been climbing to epidemic proportions among the Indian population. Various factors that are thought to contribute to this rising epidemic include urbanization of rural areas, large-scale migration of rural population to urban areas, increase in sedentary lifestyle, abdominal obesity, metabolic syndrome, diabetes, inadequate consumption of fruits and vegetables, increased use of fried, processed and fast foods, tobacco abuse, poor awareness and control of CAD risk factors, unique dyslipidemia (high triglycerides, low HDL-cholesterol levels), and possible genetic predisposition due to lipoprotein (a) [Lp(a)] excess. The effect of established, as well as novel, risk factors is multiplicative, not just additive (total effect>sum of parts). The management would require aggressive individual, societal, and governmental (policy and regulatory) interventions. Indians will require specific lower cut-offs and stricter goals for treatment of various risk factors than is currently recommended for western populations. To this end, the First Indo-US Healthcare Summit was held in New Delhi, India on December 14 and 15, 2007. The participants included representatives from several professional entities including the American Association of Physicians of Indian origin (AAPI), Indian Medical Association (IMA), Medical Council of India (MCI), and Government of India (GOI) with their main objective to address specific issues and provide precise recommendations to implement the prevention of CAD among Indians. The summary of the deliberations by the committee on "CAD among Asian Indians" and the recommendations are presented in this document. OBJECTIVES: Discussion of demographics of CAD in Indians-both in India and abroad, current treatment strategies, primordial, primary, and secondary prevention. Development of specific recommendations for screening, evaluation and management for the prevention of CAD disease epidemic among Asian Indians. Recommendations for improving quality of care through professional, public and private initiatives.

Enhanced soluble production of biologically active recombinant human p38 mitogen-activated-protein kinase (MAPK) in Escherichia coli.

The conditions were optimized for maximum soluble yield of biologically active recombinant p38alpha mitogen activated protein kinase (MAPK) vis-à-vis insoluble fraction (inclusion body formation). This study reports a rapid, economical and single step purification process for the overproduction of GST tagged p38alpha MAPK. A yield of 18 mg of highly purified and soluble protein per liter of bacterial culture within 6 h timeframe was achieved. The purified protein was found to be biologically suitable for phosphorylation by upstream kinases and was catalytically active. We further demonstrated that our in-house p38alpha MAPK is more potent (>30%) than a commercially available enzyme.

Atherogenic dyslipidemia and diabetes mellitus: what's new in the management arena?

When compared with the general population, the diabetic population is at higher risk of cardiovascular disease (CVD), as predicted by the Framingham Risk Score calculations (10-year risk 20%). For this reason diabetes is considered a "coronary disease equivalent" condition, as classified by the National Cholesterol Education Program Adult Treatment Panel (NCEP-ATP) III. Furthermore, patients with diabetes who experience a myocardial infarction have a poorer prognosis than nondiabetic patients, which contributes to their overall higher mortality. Dyslipidemia is a major underlying risk factor contributing to the excess CVD risk, and is usually more atherogenic in the presence of diabetes. It is uniquely manifested by raised levels of triglycerides, low levels of high-density lipoprotein cholesterol, and smaller, denser, and more atherogenic low-density lipoprotein particles. Recent trials have suggested the need for more aggressive treatment of dyslipidemia in this subpopulation than the current recommendations by the NCEP-ATP III. This review addresses the newer developments in the diabetes arena in terms of our current understanding of atherogenic dyslipidemia in diabetes and data from the latest randomized trials addressing its management.

Low high-density lipoprotein cholesterol: current status and future strategies for management.

Atherosclerotic cardiovascular disease is the foremost cause of death and disability in the Western world, and it is rapidly becoming so in the developing nations. Even though the use of statin therapy aiming at the low-density lipoprotein cholesterol (LDL) has significantly reduced cardiovascular events and mortality, substantial residual cardiac events still occur in those being treated to the currently recommended targets. In fact, residual risk is also seen in those who are treated "aggressively" such as the "high risk" patients so defined by the National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP III). Consequently, one must look for the predictors of risk beyond LDL reduction. High-density lipoprotein cholesterol (HDL) is the next frontier. The protectiveness of elevated HDL against atherosclerosis is well described in the literature. HDL subdues several atherogenic processes, such as oxidation, inflammation, cell proliferation and thrombosis. It also helps mobilize the excess LDL via reverse cholesterol transport. Low levels of HDL have been shown to be independent predictors of risk. Thus, therapies to raise the HDL hold promise for additional cardiac risk reduction. In this regard, several randomized trials have recently tested this hypothesis, especially in patients at high risk. In addition to the use of aggressive lifestyle modification, clinical outcomes have been measured following augmentation of HDL levels with various treatment modalities, including aggressive statin therapy, combination therapy with fibrates and niacin, and direct HDL-raising drug treatments. These data for low HDL as an independent risk factor and as the new treatment target are reviewed in this paper.

Cardiac risk stratification: role of the coronary calcium score.

Coronary artery calcium (CAC) is an integral part of atherosclerotic coronary heart disease (CHD). CHD is the leading cause of death in industrialized nations and there is a constant effort to develop preventative strategies. The emphasis is on risk stratification and primary risk prevention in asymptomatic patients to decrease cardiovascular mortality and morbidity. The Framingham Risk Score predicts CHD events only moderately well where family history is not included as a risk factor. There has been an exploration for new tests for better risk stratification and risk factor modification. While the Framingham Risk Score, European Systematic Coronary Risk Evaluation Project, and European Prospective Cardiovascular Munster study remain excellent tools for risk factor modification, the CAC score may have additional benefit in risk assessment. There have been several studies supporting the role of CAC score for prediction of myocardial infarction and cardiovascular mortality. It has been shown to have great scope in risk stratification of asymptomatic patients in the emergency room. Additionally, it may help in assessment of progression or regression of coronary artery disease. Furthermore, the CAC score may help differentiate ischemic from nonischemic cardiomyopathy.

The interaction between clopidogrel and proton pump inhibitors (PPI): is there any clinical relevance?

The potential interaction between clopidogrel and proton pump inhibitors (PPI) in patients with acute coronary syndrome (ACS) raises serious concerns for cardiologists. However, in patients on this combination of drugs, there is no conclusive evidence of an increase in adverse cardiovascular events. From pharmacologic and pharmacodynamic perspectives, there is a real interaction between clopidogrel and PPIs because of the competitive inhibition of CYP2C19 isoenzyme which is required for biotransformation of clopidogrel to its active metabolite. The consequent decrease in the availability of this active metabolite leads to attenuation of antiplatelet efficacy of clopidogrel. In several observational trials, it was shown that decreased antiplatelet effect of clopidogrel due to PPIs may translate into poor cardiovascular outcomes. However, an incomplete RCT (COGENT) and a post hoc analysis of two large trials (PRINCIPLE-TIMI 44 and TRITON-TIMI 38 trial) showed no significant adverse cardiovascular events with this combination. Caution is however needed in patients who are hypometabolizers of clopidogrel putting them at a higher risk of adverse coronary events. Since 3% of patients are likely to be hypometabolizers of clopidogrel, routine combination of clopidogrel and PPIs should be avoided. There is a heightened awareness of this interaction following multiple advisory warnings. At the same time, one should not withhold PPIs in patients who are at a high risk of developing gastrointestinal (GI) bleeding. In these patients, selected choices of PPI such as pantoprazole may be helpful and for low risk patients, serious consideration should be given to H(2) receptor antagonists or antacids. Therefore, while not compromising the cardioprotective effect of antiplatelet agents, the gastroprotective benefit of PPI should be strongly considered in patients who need both. Health care providers should remain alert to more outcome data. Future researchers will need to demonstrate the safety of coadministration of PPIs and clopidogrel and trials should be powered to detect major adverse cardiovascular events and facilitate risk stratification based on genetic polymorphism.

Coronary computed tomographic angiography (CCTA) in community hospitals: "current and emerging role".

Coronary computed tomographic angiography (CCTA) is a rapidly evolving test for diagnosis of coronary artery disease. Although invasive coronary angiography is the gold standard for coronary artery disease (CAD), CCTA is an excellent noninvasive tool for evaluation of chest pain. There is ample evidence to support the cost-effective use of CCTA in the early triage process of patients presenting with chest pain in the emergency room. CCTA plays a critical role in the diagnosis of chest pain etiology as one of potentially fatal conditions, aortic dissection, pulmonary embolism, and myocardial infarction. This 'triple rule out' protocol is becoming an increasingly practicable and popular diagnostic tool in ERs across the country. In addition to a quick triage of chest pain patients, it may improve quality of care, decrease cost, and prevent medico-legal risk for missing potentially lethal conditions presenting as chest pain. CCTA is also helpful in the detection of subclinical and vulnerable coronary plaques. The major limitations for wide spread acceptance of this test include radiation exposure, motion artifacts, and its suboptimal imaging with increased body mass index.

Reducing morbidity and mortality in high risk patients with statins.

Residual coronary heart disease remains a significant problem even after adequate statin therapy for cardiovascular risk reduction as currently recommended by the Adult Treatment Panel III (ATP-III) of the National Cholesterol Education Program (NCEP). This is particularly true for the high risk patients as defined by ATP-III that includes those patients who have a greater than 20% 10-year risk of adverse cardiac events. For such patients the current goal of a low-density lipoprotein cholesterol (LDL-cholesterol) maintenance level of < or =100 mg/dL plasma appears to be suboptimal. Accumulating data from several recent randomized studies of more aggressive LDL-cholesterol reduction to levels below 70 mg/dL in the high risk patients favor acceptance of such a new lower target for LDL-cholesterol using more intensive statin therapy which would affect the treatment strategy for patients with coronary heart disease pre-percutaneous intervention, metabolic syndrome, diabetes mellitus, congestive heart failure, cerebrovascular disease and chronic kidney disease.

Low high-density lipoprotein cholesterol and increased cardiovascular disease risk: an analysis of statin clinical trials.

It is well established that low high-density lipoprotein (HDL) cholesterol is a risk factor for coronary artery disease (CAD). Growing evidence from epidemiologic as well as intervention studies have identified that a low level of HDL cholesterol contributes to cardiovascular disease risk. In addition, a number of clinical trials have substantiated that an inverse association between HDL cholesterol concentrations and cardiovascular risk exists. Decreasing low-density lipoprotein cholesterol levels with statins has a major impact on cardiovascular risk reduction, and statin therapy plays a significant role in the management of CAD. However, low levels of HDL cholesterol remain as a cardiovascular risk factor despite statin therapy. This article presents an overview of statin clinical trials and discusses implications for the clinical management of patients with low HDL cholesterol levels and increased cardiovascular risk.

Thinking beyond low-density lipoprotein cholesterol: strategies to further reduce cardiovascular risk.

Several large statin trials and meta-analyses have demonstrated a reduction in low-density lipoprotein cholesterol (LDL-C) and cardiovascular morbidity and mortality. Some trials have also highlighted the significance of residual cardiovascular risk after treatment of LDL-C to target levels. This reflects the complex nature of residual cardiovascular risk. This residual risk is partially due to low HDL-C and high triglycerides (TG) despite achievement of LDL goals with statin therapy. The NCEP ATP III guidelines reported that low HDL-C is a significant and an independent risk factor for coronary heart disease (CHD) and is inversely related to CHD. Epidemiologic studies have also shown a similar inverse relationship of HDL-C with CHD. High-density lipoprotein cholesterol (HDL-C) may directly participate in the anti-atherogenic process by promoting efflux of cholesterol of the foam cells of atherogenic lesions. Many studies have demonstrated multiple anti-atherogenic actions of HDL-C and its role in promoting efflux of cholesterol from the foam cells. The residual risk by increased TG with or without low HDL-C can be assessed by calculating non-HDL-C and a reduction in TG results in decreased CHD.

Aspirin and clopidogrel hyporesponsiveness and nonresponsiveness in patients with coronary artery stenting.

Patients undergoing coronary artery stenting receive an antiplatelet regimen to reduce the risk of antithrombotic complications. Current guidelines recommend the use of acetyl salicylic acid (aspirin) and clopidogrel as evidenced by large clinical trials. There has been a concern about variable responses of patients to aspirin and clopidogrel which may predispose them to subacute stent thrombosis or late stent thrombosis. Up to 25% of patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) were found to have hyporesponsiveness or resistance to clopidogrel which may predispose them to recurrent events. Dual antiplatelet regimen is a standard therapy in these patients and there is always a concern about variable responses to aspirin and clopidogrel predisposing them to acute coronary syndrome (ACS). Prevalence of this hyporesponsiveness or resistance may be due to noncompliance, genetic mutations, co-morbid situations and concomitant use of other drugs. This issue is of considerable importance in the era of coronary drug eluting stents when a long-term dual antiplatelet regimen is needed. This paper is a review for clinicians taking care of such patients with hyporesponsiveness or nonresponsiveness to dual antiplatelet regimen.

Expanding roles for atorvastatin.

Atherosclerosis, especially when manifested as coronary artery disease (CAD), continues to be the number one cause of mortality and morbidity in developed nations and will soon become so in developing countries. Survivors of an acute heart attack have an increased risk of illness and death that is 1.5-15 times greater than in the general population. Sudden death occurs in myocardial infarction (MI) survivors at a rate 4-6 times greater than in the general population. After an initial recognized MI, 25% of male and 38% of female survivors die within 1 year. Within 6 years after a recognized MI, 18% of men and 35% of women will have a second MI, 7% of men and 6% of women will suffer sudden death, and 22% of men and 46% of women will be disabled with heart failure. Aggressive secondary prevention, therefore, is the key to containing and reversing the "malignant" natural history of CAD, since patients with CAD or CAD risk equivalents are already in the "high risk" category according to the Adult Treatment Panel III (ATP III) of the National Cholesterol Education rogram (NCEP). Treatment of dyslipidemia, especially the reduction of low-density lipoprotein (LDL) cholesterol levels to below 100 mg/dl, was recommended by the 2001 NCEP-ATP Guidelines. In 2004, based on the increasing evidence from several major clinical trials between 2001 and 2004, the NCEP-ATP reaffirmed its LDL goal of < 100 mg/dl in patients with CAD or coronary disease risk equivalents (including multiple risk factors), with an optional LDL goal of < 70 mg/dl in very-high-risk patients (including patients with established coronary heart disease plus other highrisk conditions) Findings from major studies, such as the Treating to New Targets (TNT) study, the Scandinavian Simvastatin Survival Study (4S), the Collaborative Atorvastatin Diabetes Study (CARDS), the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) trial and, more recently, the Lipid-Lowering Arm of the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT-LAA), lend support to the idea that greater LDL cholesterol lowering than that achieved with standard doses of statins may be warranted in patients with CAD and metabolic syndrome, CAD and diabetes, CAD and congestive heart failure, and CAD and renal insufficiency. On the other hand, additional lipid reduction may also be warranted in patients with risk factors such as diabetes, hypertension or a history of stroke, but without manifest CAD and despite relatively normal cholesterol levels. These newer indications for statins, atorvastatin in particular, as part of more aggressive secondary and primary prevention, are reviewed in this paper.