The effect of proton pump inhibitors on fracture risk: report from the Canadian Multicenter Osteoporosis Study

A large Canadian cohort was studied over 10 years to see if proton pump inhibitor (PPI) use increased the risk of sustaining a fragility fracture. We found an increased risk of fracture in individuals who used PPIs. The risk remained after controlling for other known fracture risk factors.

INTRODUCTION

Multiple retrospective studies have linked proton pump inhibitor use with increased risk of fragility fracture. We prospectively studied the association between PPI use and fracture in a large cohort over a 10-year period while controlling for known fracture risk factors.

METHODS

We studied 9,423 participants in the Canadian Multicenter Osteoporosis Study. The cohort was formed in 1995-1997 and followed for 10 years with monitoring for incident nontraumatic fracture and PPI use. Cox regression analyses were used to assess the association between PPI use and incident fracture risk.

RESULTS

PPI use, coded as a time-dependent variable, was associated with a shorter time to first nontraumatic fracture, hazard ratio (HR)=1.75 (95% confidence interval (CI) 1.41-2.17, p<0.001). After controlling for multiple risk factors, including femoral neck bone density, the association remained significant, HR=1.40 (95% CI 1.11-1.77, p=0.004). Similar results were obtained after controlling for bisphosphonate use, using PPI "ever" use, or when the outcome was restricted to hip fracture.

CONCLUSIONS

In this large prospective population-based cohort study, we found an association between PPI use and increased risk of fragility fracture. Although the increased risk found was modest, this finding is important, given the high prevalence of PPI use and the excess morbidity and mortality associated with osteoporosis-related fractures.

Practical tips for intrauterine devices use in adolescents

The American Congress of Obstetricians and Gynecologists (ACOG) has endorsed intrauterine devices (IUDs) as first-line contraceptive choices for both nulliparous and parous adolescents. The committee opinion did address some of the practical elements of IUD use in adolescents, but because these practical concerns may be barriers to use for both teens and clinicians, this review is devoted to "practical tips," based on the available literature as well as the author's clinical experience. Counseling, informed consent, techniques of pain management, and preventive guidance about possible side effects are addressed in an effort to promote successful use of this long-acting reversible contraception (LARC) option.

Metabolic disturbances and worsening of atherosclerotic lesions in ApoE-/- mice after cola beverages drinking

Background

Atherosclerosis is a major health burden. Metabolic disorders had been associated with large consumption of soft drinks. The rising incidence of atherosclerosis and metabolic alterations warrants the study of long-term soft drink consumption’ effects on metabolism and atherosclerosis in genetic deficiency of apolipoprotein E which typically develops spontaneous atherosclerosis and metabolic alterations.

Methods

ApoE^-/- mice were randomized in 3 groups accordingly with free access to: water (W), regular cola (C) or light cola (L). After 8 weeks, 50% of the animals in each group were euthanized (Treatment: W₈, C₈, L₈). The remaining mice (all groups) drank water for 8 weeks and were euthanized (Washout: W₁₆, C₁₆, L₁₆). Body weight and food and drink consumption were periodically measured. Blood was collected (biochemistry). At autopsy, transverse aortic sinus sections were serially cut and stained (histomorphometry); livers and kidneys were processed (microscopy). MANOVA (identification of variance factors) was followed by ANOVA and LSD tests (within-factor differences between levels). Conventionally a p< 0.05 was considered significant.

Results

Treatment increased drinking volumes (vs W₈: 4 fold C₈, p<0.0001; +47% L₈, p<0.02). Only C reduced eating amounts (–54%, p<0.05 vs W₈). I). Compared with W₈: C₈ developed hyperglycemia (+43%, p<0.03) and increased non-HDL cholesterol (+54%, p<0.05); L₈ showed decreased glycemia (–15%, p<0.05 vs W₈) and increased creatinine (2.5 fold, p<0.04), urea (+74, p<0.03) and aspartate-aminotransferase (2.8 fold, p<0.05). Hypercreatininemia was observed in L₁₆ (2.7 fold vs W₁₆, p<0.05). Hypertriglyceridemia (+91%, p<0.008) and hyperuremia (+68%, p<0.03) developed over time of study (age). II). Treatment caused plaque area increase (vs W₈: 28% C₈, p<0.02 and 50% L₈, p<0.01; vs W₁₆: 43% C₁₆, p<0.05 and 68% L₁₆, p<0.02) and stenosis (vs W₈: 38% C₈, p<0.04 and 57% L₈, p<0.01; vs W₁₆: 71% C₁₆, p<0.01 and 46% L₁₆, p<0.04). Age also caused plaque area increase (56%, p<0.04). Treatment- and age-effects on plaque enlargement were additive.

Conclusion

Cola beverages caused atherosclerotic lesions’ enlargement with metabolic (C) or non metabolic disturbances (L). ApoE^-/- mice were particularly sensitive to L treatment. These findings may likely relate to caramel colorant and non-nutritive sweeteners in cola drinks and have potential implications in particularly sensitive individuals.

Evaluation of Cardiac Mitochondrial Function by a Nuclear Imaging Technique using Technetium-99m-MIBI Uptake Kinetics

Mitochondria play an important role in energy production for the cell. The proper function of a myocardial cell largely depends on the functional capacity of the mitochondria. Therefore it is necessary to establish a novel and reliable method for a non-invasive assessment of mitochondrial function and metabolism in humans. Although originally designed for evaluating myocardial perfusion, ^99mTc-MIBI can be also used to evaluate cardiac mitochondrial function. In a clinical study on ischemic heart disease, reverse redistribution of ^99mTc-MIBI was evident after direct percutaneous transluminal coronary angioplasty. The presence of increased washout of ^99mTc-MIBI was associated with the infarct-related artery and preserved left ventricular function. In non-ischemic cardiomyopathy, an increased washout rate of ^99mTc-MIBI, which correlated inversely with left ventricular ejection fraction, was observed in patients with congestive heart failure. Increased ^99mTc-MIBI washout was also observed in mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) and in doxorubicin-induced cardiomyopathy. Noninvasive assessment of cardiac mitochondrial function could be greatly beneficial in monitoring possible cardiotoxic drug use and in the evaluation of cardiac damage in clinical medicine.

Sudden death and physical exercise: timely diagnosis of congenital anomalies of the coronary arteries with the new 320-slide multi-detector computed tomography

Congenital abnormalities of the coronary arteries here described are an uncommon form of structural heart disease. Nevertheless, they deserve attention because may cause chest pain and, in some cases, sudden cardiac death even during exercise. Traditional angiography has limitations due to its projectional and invasive nature. The recent development of the 320-slide multi-detector computer tomography with low radiation exposure has the potential to modify the current diagnostic work-up, as it allows even in young people a timely identification of clinical significant coronary anomalies minimizing the risks related to radiation exposure.

Impaired mitochondrial function in chronically ischemic human heart

Chronic ischemic heart disease is associated with myocardial hypoperfusion. The resulting hypoxia potentially inflicts damage upon the mitochondria, leading to a compromised energetic state. Furthermore, ischemic damage may cause excessive production of reactive oxygen species (ROS), producing mitochondrial damage, hereby reinforcing a vicious circle. Ischemic preconditioning has been proven protective in acute ischemia, but the subject of chronic ischemic preconditioning has not been explored in humans. We hypothesized that mitochondrial respiratory capacity would be diminished in chronic ischemic regions of human myocardium but that these mitochondria would be more resistant to ex vivo ischemia and, second, that ROS generation would be higher in ischemic myocardium. The aim of this study was to test mitochondrial respiratory capacity during hyperoxia and hypoxia, to investigate ROS production, and finally to assess myocardial antioxidant levels. Mitochondrial respiration in biopsies from ischemic and nonischemic regions from the left ventricle of the same heart was compared in nine human subjects. Maximal oxidative phosphorylation capacity in fresh muscle fibers was lower in ischemic compared with nonischemic myocardium (P < 0.05), but the degree of coupling (respiratory control ratio) did not differ (P > 0.05). The presence of ex vivo hypoxia did not reveal any chronic ischemic preconditioning of the ischemic myocardial regions (P > 0.05). ROS production was higher in ischemic myocardium (P < 0.05), and the levels of antioxidant protein expression was lower. Diminished mitochondrial respiration capacity and excessive ROS production demonstrate an impaired mitochondrial function in ischemic human heart muscle. No chronic ischemic preconditioning effect was found.

An assessment of the vulnerability of carotid plaques: a comparative study between intraplaque neovascularization and plaque echogenicity

BACKGROUND

Carotid plaque echolucency as detected by Color Doppler ultrasonography (CDUS) has been used as a potential marker of plaque vulnerability. However, contrast-enhanced ultrasound (CEUS) has recently been shown to be a valuable method to evaluate the vulnerability and neovascularization within carotid atherosclerotic plaques. The aim of this study was to compare CEUS and CDUS in the assessment of plaque vulnerability using transcranial color Doppler (TCD) monitoring of microembolic signals (MES) as a reference technique.

METHODS

A total of 46 subjects with arterial stenosis (≥ 50%) underwent a carotid duplex ultrasound, TCD monitoring of MES and CEUS (SonoVue doses of 2.0 mL) within a span of 3 days. The agreement between the CEUS, CDUS, and MES findings was assessed with a chi-square test. A p-value less than 0.05 was considered statistically significant.

RESULTS

Neovascularization was observed in 30 lesions (44.4%). The vascular risk factors for stroke were similar and there were no age or gender differences between the 2 groups. Using CEUS, MES were identified in 2 patients (12.5%) within class 1 (non-neovascularization) as opposed to 15 patients (50.0%) within class 2 (neovascularization) (p = 0.023). CDUS revealed no significant differences in the appearance of the MES between the 2 groups (hyperechoic and hypoechoic) (p = 0.237).

CONCLUSION

This study provides preliminary evidence to suggest that intraplaque neovascularization detected by CEUS is associated with the presence of MESs, where as plaque echogenicity on traditional CDUS does not. These findings argue that CEUS may better identify high-risk plaques.

How does moxibustion possibly work?

"Acupmoxa" is a hybrid word of "acupuncture" and "moxibustion" that more closely resembles the Chinese ideograph for this treatment. People in Western countries are more familiar with acupuncture, while moxibustion is less popular, partially due to the paucity of scientific studies. Although the evidence-based efficacy of moxibustion needs to be further clarified, the mechanisms by which moxibustion may work include temperature-related and nontemperature-related ones. Local somatothermal stimulation (LSTS), one type of moxibustion, is achieved by application of a heat source to and above the acupoint. Such mild heat stimulation of the acupoint induces little skin damage, in contrast to the burning effect of moxibustion, but does provoke mild oxidative stress in the viscera. Thus, preconditioned LSTS at the peripheral acupoints LR 14 and PC 6 of animals is able to induce visceral HSP70 expression and to protect the liver and the heart against ischemia-reperfusion injury. Nontemperature-related mechanisms include smoke, herbs, and biophysical (far infrared) stimulation. We conclude that LSTS, a remote preconditioning method, has potential clinical usefulness. However, evidence-based efficacy and safety studies involving large-scaled clinical trials are needed in order that this approach will pass muster with Western scientists.

Platelet function tests in clinical cardiology: unfulfilled expectations

This review is a critical evaluation of publications in the past decade on the usefulness of platelet function tests (PFTs) in clinical cardiology, in aiding diagnosis, predicting risk, and monitoring therapy. The ideal PFT should: 1) detect baseline platelet hyperreactivity; 2) allow individualization of antiplatelet medication; 3) predict thrombotic risk; and 4) predict bleeding risk. The practicalities of clinical cardiology demand rapid, accurate, and reliable tests that are simple to operate at the bedside and available 24 h a day, 7 days a week. Point-of-care PFTs most widely evaluated clinically include PFA-100 and VerifyNow. None of these tests can reliably detect platelet hyperreactivity and thus identify a prothrombotic state. Identification of antiplatelet nonresponsiveness or hyporesponsiveness is highly test specific, and does not allow individualization of therapy. The power of PFTs in predicting thrombotic events for a given individual is variable and often modest, and alteration of antithrombotic treatment on the basis of the results of PFTs has not been shown to alter clinical outcome. PFTs in current mainstream use cannot reliably assess bleeding risk. These tests have been in use for over a decade, but the hopes raised by PFTs in clinical practice remain unfulfilled. Although physiologically relevant measurement of platelet function now is more important than ever, a critical reappraisal of available techniques in light of clinical requirements is needed. The use of native blood, global stimulus instead of individual agonists, contribution of thrombin generation by activated platelets to the test results, and establishment of a PFT therapeutic range for each antiplatelet drug should be considered and is discussed.

Pulmonary endarterectomy in chronic thromboembolic pulmonary hypertension: How can patients be better selected?

Chronic thromboembolic pulmonary hypertension (CTEPH) comprises organizing thrombotic obstructions in the pulmonary arteries by nonresolving thromboemboli, formation of fibrosis and remodeling of pulmonary blood vessels. Surgical pulmonary endarterectomy (PEA) is the therapy of choice for patients with surgically accessible CTEPH, which leads to a profound improvement in hemodynamics, functional class and survival. Selecting the candidates that will benefit from surgery is still a challenging task. Criteria for surgical suitability have been described but the decision-making for or against surgical intervention remains still subjective. The optimal characterization of the reciprocal contribution of large vessel and small vessel disease in the elevation of pulmonary vascular resistance is crucial for the indication and outcome of PEA. Recently, Toshner et al intended to validate the partition resistance into small and large vessels compartments (upstream resistance: Rup) by the occlusion technique in the preoperative assessment of PEA. We discuss the advantages and disadvantages of Rup and compare it with other hemodynamic predictor to evaluate operative risk in CTEPH patients.

Air pollution and heart failure: Relationship with the ejection fraction

AIM: To study whether the concentrations of particulate matter in ambient air are associated with hospital admission due to heart failure in patients with heart failure with preserved ejection fraction and reduced ejection fraction.

METHODS: We studied 353 consecutive patients admitted into a tertiary care hospital with a diagnosis of heart failure. Patients with ejection fraction of ≥ 45% were classified as having heart failure with preserved ejection fraction and those with an ejection fraction of < 45% were classified as having heart failure with reduced ejection fraction. We determined the average concentrations of different sizes of particulate matter (< 10, < 2.5, and < 1 μm) and the concentrations of gaseous pollutants (carbon monoxide, sulphur dioxide, nitrogen dioxide and ozone) from 1 d up to 7 d prior to admission.

RESULTS: The heart failure with preserved ejection fraction population was exposed to higher nitrogen dioxide concentrations compared to the heart failure with reduced ejection fraction population (12.95 ± 8.22 μg/m³vs 4.50 ± 2.34 μg/m³, P < 0.0001). Multivariate analysis showed that nitrogen dioxide was a significant predictor of heart failure with preserved ejection fraction (odds ratio ranging from (1.403, 95%CI: 1.003-2.007, P = 0.04) to (1.669, 95%CI: 1.043-2.671, P = 0.03).

CONCLUSION: This study demonstrates that short-term nitrogen dioxide exposure is independently associated with admission in the heart failure with preserved ejection fraction population.

Successful implanted pacemaker for an extreme inhibitory reflex syncope evoked by post herpetic trigeminal neuralgia

Syncope is defined as a transient loss of consciousness due to cerebral hypoperfusion characterized by rapid onset, short duration, and spontaneous complete recovery. Numerous causes of syncope have been described. Vasovagal syncope is the most common with a number of precipitants. We report a case of post herpetic trigeminal neuralgia leading to neurocardiogenic syncope. These episodes were preceded by severe stabbing left frontal headaches followed by significant sinus bradycardia, asystole, and syncope requiring pacemaker implantation. To our knowledge only one previous case of post herpetic trigeminal neuralgia leading to syncope has been reported. <Learning objective: Neuralgia-associated syncope is a rare phenomenon. Failing to recognize and treat appropriately may be associated with recurring episodes of syncope with significant lifestyle limitations. Although post herpetic neuralgia is treatable, one should be prepared to insert a pacemaker if treatment fails to control symptoms that progress to cardioinhibitory syncope.>.

Redox regulation of sodium and calcium handling

SIGNIFICANCE

In heart failure (HF), contractile dysfunction and arrhythmias result from disturbed intracellular Ca handling. Activated stress kinases like cAMP-dependent protein kinase A (PKA), protein kinase C (PKC), and Ca/calmodulin-dependent protein kinase II (CaMKII), which are known to influence many Ca-regulatory proteins, are mechanistically involved.

RECENT ADVANCES

Beside classical activation pathways, it is becoming increasingly evident that reactive oxygen species (ROS) can directly oxidize these kinases, leading to alternative activation. Since HF is associated with increased ROS generation, ROS-activated serine/threonine kinases may play a crucial role in the disturbance of cellular Ca homeostasis. Many of the previously described ROS effects on ion channels and transporters are possibly mediated by these stress kinases. For instance, ROS have been shown to oxidize and activate CaMKII, thereby increasing Na influx through voltage-gated Na channels, which can lead to intracellular Na accumulation and action potential prolongation. Consequently, Ca entry via activated NCX is favored, which together with ROS-induced dysfunction of the sarcoplasmic reticulum can lead to dramatic intracellular Ca accumulation, diminished contractility, and arrhythmias.

CRITICAL ISSUES

While low amounts of ROS may regulate kinase activity, excessive uncontrolled ROS production may lead to direct redox modification of Ca handling proteins. Therefore, depending on the source and amount of ROS generated, ROS could have very different effects on Ca-handling proteins.

FUTURE DIRECTIONS

The discrimination between fine-tuned ROS signaling and unspecific ROS damage may be crucial for the understanding of heart failure development and important for the investigation of targeted treatment strategies.

Oxidative stress and cardiovascular health: therapeutic potential of polyphenols

Reactive oxygen species (ROS) are important in normal cellular function and physiology. However, oxidative stress resulting from an accumulation of ROS has a detrimental impact on cellular function, and ROS has been implicated in the pathogenesis of a number of diseases, including cardiovascular diseases. This review provides a summary of the impact of ROS on cardiovascular health and diseases, highlighting the therapeutic use of antioxidants. In addition, this review summarizes the health benefits of polyphenols, and the recent progress on understanding the cellular and physiological actions by which polyphenols may impart their beneficial properties on cardiovascular health.

Utility of an advanced digital electronic stethoscope in the diagnosis of coronary artery disease compared with coronary computed tomographic angiography

The detection of coronary artery microbruits, subaudible bruits too faint to be heard through standard auscultation, may provide an alternative means to diagnose coronary artery disease (CAD). The aim of this study was to test the accuracy of a novel digital electronic stethoscope, the Cardiac Sonospectrographic Analyzer (CSA; SonoMedica model 3.0, SonoMedica, Inc., Vienna, Virginia, United States Food and Drug Administration 510[k] cleared) to diagnose CAD compared to gold-standard diagnosis using cardiac computed tomographic (CT) angiography. In this blinded, single-site study, adults previously referred for CT imaging were selected. Patients underwent CT and CSA evaluations. CSA exams entailed recording heart sounds at 9 positions on the chest for 40 seconds at each position. An algorithm then processed these data to generate a microbruit score. The CT scans were read blinded to patients' microbruit scores. Sensitivity and specificity of the CSA in detecting CAD compared to CT imaging were estimated using standard receiver-operating characteristic curves calculated from logistic regression models. A total of 161 patients, aged 57 ± 13 years (range 22 to 85), 53% with hypertension and 40% with obesity (body mass index ≥30 kg/m(2)), completed the protocol and had evaluable CT and CSA examinations. The overall sensitivity of the CSA to identify >50% stenosis in any major epicardial coronary artery as determined by CT imaging was 89.5% (p <0.0001). Gender-specific models based on smaller sample sizes had slightly poorer results and lower specificity among men with heavy chest hair. In conclusion, the CSA showed high sensitivity and specificity for the detection of significant early CAD in an outpatient setting and represents a new noninvasive device for detecting abnormal coronary blood flow as occurs in CAD.

Relaxation of human pulmonary arteries by PPARγ agonists

It has been suggested that activation of nuclear peroxisome proliferator-activated receptors γ (PPARγ) may represent a new strategy for the treatment of pulmonary arterial hypertension. It has been demonstrated that PPARγ activation relaxed the isolated mouse pulmonary artery. The aims of the present study were to examine whether and to which extent the two PPARγ agonists rosiglitazone and pioglitazone relax the isolated human pulmonary artery and to investigate the underlying mechanism(s). Isolated human pulmonary arteries were obtained from patients without clinical evidence of pulmonary hypertension during resection of lung carcinoma. Vasodilatory effects of PPARγ agonists were examined on endothelium-intact or endothelium-denuded vessels preconstricted with the thromboxane prostanoid receptor agonist U-46619. Rosiglitazone and pioglitazone (0.01–100 μM) caused a concentration- and/or time-dependent full relaxation of U-46619-preconstricted vessels. The rosiglitazone-induced relaxation was attenuated by the PPARγ antagonist GW9662 1 μM, endothelium denudation, the nitric oxide synthase inhibitor L-NAME 300 μM, the cyclooxygenase inhibitor indomethacin 10 μM, and the K_ATP channel blocker glibenclamide 10 μM. The prostacyclin IP receptor antagonist RO1138452 1 μM shifted the concentration–response curve for rosiglitazone to the right. The PPARγ agonists pioglitazone and rosiglitazone relax human pulmonary arteries. The rosiglitazone-induced vasorelaxation is partially endothelium-dependent and involves PPARγ receptors, arachidonic acid degradation products, nitric oxide, and K_ATP channels. Thus, the relaxant effect of PPARγ agonists in human pulmonary arteries may represent a new therapeutic target in pulmonary arterial hypertension.

Dexamethasone-eluting vascular stents

Percutaneous transluminal angioplasty (PTA) with stenting is widely used in the treatment of vascular disorders, but restenosis remains a significant problem. Drug-eluting stents (DES) have been developed as an attempt to reduce the intimal response leading to restenosis. Drugs used in DES include mainly immunosuppressive and anti-proliferative compounds. Glucocorticoids are also an interesting possibility for those purposes because they have anti-proliferative effects in vascular smooth muscle cells and down-regulate the production of cytokines and growth factors driving inflammation and fibrosis. In this MiniReview, feasibility and safety of drug-eluting metal and biodegradable vascular stents are discussed with special emphasis on dexamethasone-eluting stents.

Antioxidant capacity of calendula officinalis flowers extract and prevention of radiation induced oropharyngeal mucositis in patients with head and neck cancers: a randomized controlled clinical study

This study was designed to determine the effect of Calendula officinalis flowers extract mouthwash as oral gel on radiation-induced oropharyngeal mucositis (OM) in patients with head-and-neck cancer. Forty patients with neck and head cancers under radiotherapy or concurrent chemoradiotherapy protocols were randomly assigned to receive either 2% calendula extract mouthwash or placebo (20 patients in each group). Patients were treated with telecobalt radiotherapy at conventional fractionation (200 cGy/fraction, five fractions weekly, 30–35 fractions within 4–7 weeks). The oropharyngeal mucositis was evaluated by two clinical investigators (a radiation oncologist and a dentist), using the oral mucositis assessment scale (OMAS). Trying to find out the possible mechanism of action of the treatment, total antioxidant, polyphenol and flavonoid contents, and quercetin concentration of the mouth wash were measured. Calendula mouthwash significantly decreased the intensity of OM compared to placebo at week 2 (score: 5.5 vs. 6.8, p = 0.019), week 3 (score: 8.25 vs. 10.95, p < 0.0001) and week 6 (score: 11.4 vs. 13.35, p = 0.031). Total antioxidant, polyphenol and flavonoid contents and quercetin concentration of the 2% extract were 2353.4 ± 56.5 μM, 313.40 ± 6.52 mg/g, 76.66 ± 23.24 mg/g, and 19.41 ± 4.34 mg/l, respectively. Calendula extract gel could be effective on decreasing the intensity of radiotherapy- induced OM during the treatment and antioxidant capacity may be partly responsible for the effect.

Hierarchical approaches for systems modeling in cardiac development

Ordered cardiac morphogenesis and function are essential for all vertebrate life. The heart begins as a simple contractile tube, but quickly grows and morphs into a multichambered pumping organ complete with valves, while maintaining regulation of blood flow and nutrient distribution. Though not identical, cardiac morphogenesis shares many molecular and morphological processes across vertebrate species. Quantitative data across multiple time and length scales have been gathered through decades of reductionist single variable analyses. These range from detailed molecular signaling pathways at the cellular levels to cardiac function at the tissue/organ levels. However, none of these components act in true isolation from others, and each, in turn, exhibits short- and long-range effects in both time and space. With the absence of a gene, entire signaling cascades and genetic profiles may be shifted, resulting in complex feedback mechanisms. Also taking into account local microenvironmental changes throughout development, it is apparent that a systems level approach is an essential resource to accelerate information generation concerning the functional relationships across multiple length scales (molecular data vs physiological function) and structural development. In this review, we discuss relevant in vivo and in vitro experimental approaches, compare different computational frameworks for systems modeling, and the latest information about systems modeling of cardiac development. Finally, we conclude with some important future directions for cardiac systems modeling.

Uremia and chronic kidney disease: the role of the gut microflora and therapies with pro- and prebiotics

Uremia is an illness that accompanies kidney failure and chronic kidney disease (CKD). Uremic illness is considered to be due largely to the accumulation of organic waste products that are normally cleared by the kidneys. However, uremic retention solutes are generated in part in the gastrointestinal tract (GIT), with the gut microbiota and the ensuing micro-biometabolome playing a significant role in the proliferation of uremic retention solutes. Toxins generated in, or introduced into the body via the intestine, such as advanced glycation end products, phenols, and indoles, all may contribute to the pathogenesis of CKD. Hence, it is biologically plausible, but not well recognized, that an important participant in the toxic load that contributes to CKD originates in the GIT. The microbiota that colonize the GIT perform a number of functions that include regulating the normal development and function of the mucosal barriers; assisting with maturation of immunological tissues, which in turn promotes immunological tolerance to antigens from foods, the environment, or potentially pathogenic organisms; controlling nutrient uptake and metabolism; and preventing propagation of pathogenic micro-organisms. Here, we develop a hypothesis that probiotics and prebiotics have a therapeutic role in maintaining a metabolically balanced GIT, and reducing progression of CKD and associated uremia.

Matrix metalloproteinases: drug targets for myocardial infarction

Myocardial infarction (MI) remains a major cause of morbidity and mortality worldwide. Rapid advances in the treatment of acute MI have significantly improved short-term outcomes in patients, due in large part to successes in preventing myocardial cell death and limiting infarct area during the time of ischemia and subsequent reperfusion. Matrix metalloproteases (MMPs) play key roles in post-MI cardiac remodeling and in the development of adverse outcomes. This review highlights the importance of MMPs in the injury and remodeling response of the left ventricle and also discusses their potential as therapeutic targets Additional pre-clinical and clinical research is needed to further investigate and understand the cardioprotective effects of MMPs inhibitors.

Is the neck circumference an emergent predictor for inflammatory status in obese adults?

BACKGROUND

Plasminogen Activator Inhibitor 1 (PAI-1) is a prothrombotic adipokine involved in the coagulation cascade and fibrinolysis that associated with proinflammatory adipokines may increase the risk related to obesity. Anthropometric measures are commonly used in clinical practice and, currently, neck circumference (NC) has been used as a marker of cardiovascular risk that can favour inflammatory factors.

OBJECTIVE

To verify the possible correlations between prothrombotic and pro/anti-inflammatory markers with anthropometric measurements in obese.

SUBJECTS AND METHODS

  A total of 43 obese adults were enrolled. The variables include body mass, stature, body mass index (BMI), NC, chest circumference (CC), abdominal circumference (AC), hip circumference (HC), blood pressure and blood collection used to assess the level of adipokines.

RESULTS

The sample was stratified by BMI. PAI-1 levels were positively correlated with body mass (r=0.31, p=0.04), NC (r=0.43, p=0.004), CC (r=0.40, p=0.004), AC (r=0.37, p=0.01), diastolic blood pressure (r=0.35, p=0.03), leptin/adiponectin ratio (r=0.36, p=0.01) and negatively correlated with adiponectin (r=-0.34, p=0.02). In stepwise multiple linear regression analysis, NC showed to be an independent predictor to PAI-1 when adjusted for gender and BMI, according to the age (β=0.47, p=0.02 and β=0.42, p=0.02 respectively).

CONCLUSION

In conclusion, NC could be suggested as an independent predictor higher PAI-1. This association can be a new screening of persons at an enhanced cardiovascular risk and inflammation in this obese population, so useful in clinical practice.

Mitochondrial dysfunction: a basic mechanism in inflammation-related non-communicable diseases and therapeutic opportunities

Obesity is not necessarily a predisposing factor for disease. It is the handling of fat and/or excessive energy intake that encompasses the linkage of inflammation, oxidation, and metabolism to the deleterious effects associated with the continuous excess of food ingestion. The roles of cytokines and insulin resistance in excessive energy intake have been studied extensively. Tobacco use and obesity accompanied by an unhealthy diet and physical inactivity are the main factors that underlie noncommunicable diseases. The implication is that the management of energy or food intake, which is the main role of mitochondria, is involved in the most common diseases. In this study, we highlight the importance of mitochondrial dysfunction in the mutual relationships between causative conditions. Mitochondria are highly dynamic organelles that fuse and divide in response to environmental stimuli, developmental status, and energy requirements. These organelles act to supply the cell with ATP and to synthesise key molecules in the processes of inflammation, oxidation, and metabolism. Therefore, energy sensors and management effectors are determinants in the course and development of diseases. Regulating mitochondrial function may require a multifaceted approach that includes drugs and plant-derived phenolic compounds with antioxidant and anti-inflammatory activities that improve mitochondrial biogenesis and act to modulate the AMPK/mTOR pathway.

Benefit to decrease esophageal damage using an ablation catheter with increased irrigation channels for pulmonary vein isolation

INTRODUCTION

An ablation catheter has been developed with six additional irrigation channels at the proximal end of the ablating electrode. We investigated the potential improvement of esophageal damage when the number of irrigation channels of the ablation catheter was increased during pulmonary vein isolation (PVI).

METHODS

This study included a total of 296 consecutive patients with atrial fibrillation. One hundred forty-eight patients were randomly assigned to receive PVI using an ablation catheter with six distal irrigation channels (6C) and 148 patients to receive PVI using an ablation catheter with 12 distal irrigation channels (12C). The luminal esophageal temperature (LET) was monitored in all patients.

RESULTS

A total of 639 radiofrequency energy applications (in 225 out of 296 patients) reached the cut-off temperature. The time for the LET to reach the cut-off temperature was shorter for the 6C than the 12C group, and the 6C group had a higher T max of the LET than the 12C group. Some patients experienced a transient drop in the LET (TDLET) just before the delivery of the energy. The site that caused a TDLET before the energy delivery always reached the cut-off temperature. TDLET was more frequent in the 6C group than in the 12C group.

CONCLUSIONS

The LET only showed a small difference between the 6C and 12C groups. In contrast, there may be a lower risk of esophageal injury with the 6C than the 12C if we use TDLET.

Effects of berberine on lipid profile in subjects with low cardiovascular risk

OBJECTIVE

To evaluate the efficacy as antihypercholesterolemic agent of berberine in patients with low cardiovascular risk.

RESEARCH DESIGN AND METHODS

144 Caucasian subjects were enrolled. After a 6-month run-in period following diet and practicing physical activity, patients were randomized to take placebo or berberine 500 mg twice a day, for 3 months, in a double-blind, placebo-controlled design. Berberine and placebo were then interrupted for 2 months (washout period), and all patients continued with only diet and physical activity. At the end of the washout period, patients restarted berberine or placebo twice a day for further 3 months. Anthropometric and metabolic parameters were assessed during the run-in period, at randomization, before and after the washout period.

RESULTS

A decrease of body weight and BMI was observed after the run-in period. Berberine reduced total cholesterol, triglycerides and LDL cholesterol and increased HDL cholesterol after 3 months from randomization and compared with placebo. After the washout period, lipid profile worsened; afterward, when berberine was reintroduced, lipid profile improved again both compared with the washout period, and with placebo.

CONCLUSIONS

Berberine is effective and safe to mildly improve lipid profile in subjects with low risk for cardiovascular disease.

Myoblasts and embryonic stem cells differentially engraft in a mouse model of genetic dilated cardiomyopathy

The functional and architectural benefits of embryonic stem cells (ESC) and myoblasts (Mb) transplantations into infarcted myocardium have been investigated extensively. Whereas ESC repopulated fibrotic areas and contributed to myocardial regeneration, Mb exerted their effects through paracrine secretions and scar remodeling. This therapeutic perspective, however, has been less explored in the setting of nonischemic dilated cardiomyopathies (DCMs). Our aim was to compare the integration and functional efficacy of ESC committed to cardiac fate by bone morphogenic protein 2 (BMP-2) pretreatment and Mb used as gold standard following their transplantation into the myocardium of a mouse model of laminopathy exhibiting a progressive and lethal DCM. After 4 and 8 weeks of transplantation, stabilization was observed in Mb-transplanted mice (P = 0.008) but not in groups of ESC-transplanted or medium-injected animals, where the left ventricular fractional shortening (LVFS) decreased by 32 ± 8% and 41 ± 8% respectively. Engrafted differentiated cells were consistently detected in myocardia of mice receiving Mb, whereas few or no cells were detected in the hearts of mice receiving ESC, except in two cases where teratomas were formed. These data suggest that committed ESC fail to integrate in DCM where scar tissue is absent to provide the appropriate niche, whereas the functional benefits of Mb transplantation might extend to nonischemic cardiomyopathy.

Low-density lipoprotein, its susceptibility to oxidation and the role of lipoprotein-associated phospholipase A2 and carboxyl ester lipase lipases in atherosclerotic plaque formation

An increased level of low-density lipoprotein (LDL) is a very well established risk factor of coronary artery disease (CAD). Unoxidized LDL is an inert transport vehicle of cholesterol and other lipids in the body and is thought to be atherogenic. Recently it has been appreciated that oxidized products of LDL are responsible for plaque formation properties previously attributed to the intact particle. The goal of this article is to review the recent understanding of the LDL oxidation pathway. The role of oxidized products and key enzymes (lipoprotein-associated phospholipase A2 and carboxyl ester lipase) are also extensively discussed in the context of clinical conditions.

Palmitoylethanolamide reduces early renal dysfunction and injury caused by experimental ischemia and reperfusion in mice

This study was designed to assess a protective effect of palmitoylethanolamide (PEA) in the development of inflammation after ischemia-reperfusion injury of the kidney. Moreover, to suggest a possible mechanism, renal ischemia-reperfusion was performed in mice with targeted disruption of peroxisome proliferator-activated receptor α (PPAR-α) gene (PPAR-αKO) to explain whether the observed PEA effect was dependent on PPAR-α pathway. Peroxisome proliferator-activated receptor-αKO and littermate wild-type controls (PPAR-αWT) were subjected to bilateral renal artery occlusion (30 min) and reperfusion (6 h) and received PEA (10 mg/kg i.p.) 15 min before release of clamps. Serum and urinary indicators of renal dysfunction and tubular and reperfusion injury were measured, specifically serum urea, creatinine, aspartate aminotransferase and γ-glutamyl transferase, and creatinine clearance. In addition, renal sections were used for histological scoring of renal injury and for immunologic evidence of nitrotyrosine formation, poly[adenosine diphosphate-ribose] (PAR), and adhesion molecules expression. The oxidative stress-sensitive nuclear factor κB signaling pathway was also investigated by Western blot analysis. Kidney myeloperoxidase activity and malondialdehyde levels were measured for assessment of polymorphonuclear leukocyte cell infiltration and lipid peroxidation, respectively. Apoptotic mechanisms were also investigated. Moreover, the infiltration and activation of mast cells were explored. In vivo, PEA administration during ischemia significantly reduced the increase in (i) creatinine, γ-glutamyl transferase, aspartate aminotransferase; (ii) nuclear translocation of nuclear factor κB p65; (iii) kidney myeloperoxidase activity and malondialdehyde levels; (iv) nitrotyrosine, PAR, and adhesion molecules expression; (v) the infiltration and activation of mast cells; and (vi) apoptosis. Our results clearly demonstrate that PEA significantly attenuated the degree of renal dysfunction, injury, and inflammation caused by ischemia-reperfusion injury. Moreover, the positive effects of PEA were at least in part dependent on PPAR-α pathway.

Evaluation of the anti-myocardial ischemia effect of individual and combined extracts of Panax notoginseng and Carthamus tinctorius in rats

ETHNOPHARMACOLOGICAL RELEVANCE

The decoction of combined Panax notoginseng (Burk) F.H. Chen and Carthamus tinctorius L. has a history of use in traditional medicine for the prevention and treatment of cardiovascular diseases such as angina pectoris and myocardial infarction.

AIM OF THE STUDY

In this study, we investigated the effects of individual herbal extracts and combined extracts on anti-myocardial ischemia injuries in vivo, and determined the proper dosage of Panax notoginseng (EPN) combined with Carthamus tinctorius (ECT) that could strengthen their cardio-protective effects. Meanwhile, their potential anti-oxidative stress and anti-inflammation effect were assessed.

MATERIAL AND METHODS

SD rats were orally given individual EPN 50, 100mg/kg, ECT 100, 200mg/kg, and different combinations between them. Myocardial infarction was produced by occlusion of the left anterior descending coronary artery for 24h. Infarct area was determined with 2,3,5-triphenyltetrazolium chloride (TTC) staining. The biomarkers related to myocardial ischemia injury were determined. Simultaneously, hemodynamic parameters were monitored as left ventricular systolic pressure (LVSP), LV end-diastolic pressure (LVEDP) and maximal rate of increase and decrease of left ventricular pressure (dP/dt(max)). The oxidative stress indicators and inflammatory factors were also evaluated.

RESULTS

The results showed EPN or ECT significantly reduced infarct size, improved cardiac function, decreased levels of creatine kinase (CK) and lactate dehydrogenase (LDH) (all P<0.05 vs. control ). EPN or ECT alone also restrained the oxidative stress related to myocardial ischemia injury as evidenced by decreased malondialdehyde (MDA) and elevated superoxide dismutase (SOD) activity (all P<0.05 vs. control). However, this cardio-protective effect was further strengthened by their combinations. Among all the combinations, EPN 50mg/kg plus ECT 200mg/kg showed predominant potential to reduce infarct size (22.21±1.72%, P<0.05 vs. each single, respectively), preserve cardiac function (P<0.05 vs. ECT 200mg/kg for LVEDP and -dP/dt(max)) after myocardial ischemia injury in rats. This heart protection was confirmed with the lowered cardiac troponin I (cTnI) (P<0.05 vs. ECT 200mg/kg and EPN 50mg/kg, respectively). Oxidative stress and inflammation are the two key factors in the pathogenesis of myocardial ischemia injury. In the present study, EPN 50mg/kg plus ECT 200mg/kg markedly increased SOD and GSH-Px activity (475.30±23.60U/ml, P<0.05 vs. each single, respectively), while elevated MDA level was significantly depressed. Meanwhile, the inflammatory cascade was inhibited as evidenced by decreased cytokines such as tumor necrosis factor-α (TNF-α), C-reactive protein (CRP) and interleukin-1β (IL-1β).

CONCLUSION

These results demonstrated EPN, ECT and their combinations exhibited significant cardio-protective effects. The findings suggest EPN combined with ECT may be therapeutically more useful for ameliorating anti-myocardial ischemia injuries than individual herbal extract, and EPN 50mg/kg plus ECT 200mg/kg is the appropriate combination in the present research. The cardio-protective effect of this combination was achieved partially by decreasing oxidative stress and repressing inflammatory cascade.

Effects of ethanol on aggregation, serotonin release, and amyloid precursor protein processing in rat and human platelets

It is known that oxidative stress leads to amyloid precursor protein (APP) dysregulation in platelets. Ethanol (EtOH) is a vascular risk factor and induces oxidative stress. The aim of the present study was thus to investigate whether EtOH affects APP processing in rat and human platelets. Platelets were exposed to 50 mM EtOH with and without 2 mM calcium-chloride (CaCl₂) for 20 or 180 minutes at 37°C. Platelet aggregation, serotonin release and APP isoforms 130 and 106/110 kDa were analyzed. As a control, 100 mM H₂O₂ was tested in rat platelets. Our data show that EtOH alone did not affect any of the analyzed parameters, whereas CaCl₂ significantly increased aggregation of rat and human platelets. In addition, CaCl₂ alone enhanced serotonin release in rat platelets. EtOH counteracted CaCl₂-induced aggregation and serotonin release. In the presence of CaCl₂, EtOH reduced the 130 kDa APP isoform in rat and human platelets. In conclusion, this study shows that in the presence of CaCl₂, EtOH affects the platelet function and APP processing in rat and human platelets.

Functional polymorphisms in the CYP1A1, ACE, and IL-6 genes contribute to susceptibility to community-acquired and nosocomial pneumonia

OBJECTIVES

To establish the contribution of genetic host factors to the risk of community-acquired pneumonia (CAP) and nosocomial pneumonia (NP) in the population of the Russian Federation.

METHODS

A total of 796 subjects (CAP: 334 patients, 134 controls; NP: 216 critically ill patients with NP, 105 critically ill patients without NP) were included in two case-control studies. We analyzed 13 polymorphisms in 11 genes (IL-6, TNF-α, MBL2, CCR5, NOS3, CYP1A1 (three sites), GSTM1, GSTT1, ABCB1, ACE, and MTHFR) using a tetra-primer allele-specific PCR method.

RESULTS

Individual single nucleotide polymorphism (SNP) analysis revealed a strong association between CYP1A1 rs2606345 and CAP (p=3.9 × 10(-5), odds ratio (OR) 0.42, 95% confidence interval (CI) 0.27-0.63). Three genes (CYP1A1, ACE, and IL-6) were identified that account for part of the increase in vulnerability to both diseases, CAP and NP. The carriage of three predisposing genotypes versus protective genotypes increased the CAP risk (p=0.001, OR 7.01, 95% CI 1.99-24.70) and NP risk (p=0.028, OR 4.34, 95% CI 1.15-16.45).

CONCLUSIONS

Genetic predisposition to CAP and NP is attributed to the cumulative contribution of polymorphisms at the CYP1A1, IL-6, and ACE genes, independently of age, gender, causative pathogen, and the use of mechanical ventilation, in patients in the Russian Federation.

Intense exercise training is not effective to restore the endothelial NO-dependent relaxation in STZ-diabetic rat aorta

BACKGROUND

The aim of this study was to examine the effects of intense physical training on vascular function in streptozotocin-diabetic rats. We focused on the endothelium-dependent relaxation (EDR) induced by acetylcholine (ACh) and stable ADP adenosine-5'- O - (2-thiodiphosphate) (ADPβS).

METHODS

Control or diabetic male Wistar rats (n=44) were randomly assigned to sedentary or trained groups. The training program consisted in a regular period of running on a treadmill during 8 weeks (10° incline and up to 25 m/min, 60 min/day). The reactivity of isolated thoracic aorta rings of healthy, diabetic and/or trained has been tested.

RESULTS

ACh and ADPβS-induced EDR were observed in phenylephrine (PE) pre-contracted vessels. As compared to sedentary control group, diabetic rats showed an increase in PE-induced contraction and a decrease in ACh and ADPβS-induced EDR (p<0.05). Moreover, there were no increase in ACh and ADPβS-induced EDR in diabetic rats. N-Nitro-L-Arginine Methyl Ester inhibited the nitric oxide synthase in diabetic and control rats, thereby resulting in a strong inhibition of the EDR induced by ACh and ADPβS (10-6 M).

CONCLUSION

Diabetes induced an endothelium dysfunction. Nevertheless, our intense physical training was not effective to restore the aorta endothelial function.

Genetic variation in PEAR1 is associated with platelet aggregation and cardiovascular outcomes

BACKGROUND- Aspirin or dual antiplatelet therapy with aspirin and clopidogrel is a standard therapy for patients who are at increased risk for cardiovascular events. However, the genetic determinants of variable response to aspirin (alone and in combination with clopidogrel) are not known. METHODS AND RESULTS- We measured ex vivo platelet aggregation before and after dual antiplatelet therapy in individuals (n=565) from the Pharmacogenomics of Anti-Platelet Intervention (PAPI) Study and conducted a genome-wide association study of drug response. Significant findings were extended by examining genotype and cardiovascular outcomes in 2 independent aspirin-treated cohorts: 227 percutaneous coronary intervention patients and 1000 patients of the International Verapamil SR/Trandolapril Study (INVEST) Genetic Substudy (INVEST-GENES). Results from the genome-wide association study revealed a strong association between single-nucleotide polymorphisms on chromosome 1q23 and post-dual antiplatelet therapyplatelet aggregation. Further genotyping revealed rs12041331 in the platelet endothelial aggregation receptor-1 (PEAR1) gene to be most strongly associated with dual antiplatelet therapy response (P=7.66×10(-9)). In white and black patients undergoing percutaneous coronary intervention, A-allele carriers of rs12041331 were more likely to experience a cardiovascular event or death compared with GG homozygotes (hazard ratio, 2.62; 95% confidence interval, 0.96-7.10; P=0.059; and hazard ratio, 3.97; 95% confidence interval, 1.10-14.31; P=0.035, respectively). In aspirin-treated INVEST-GENES patients, rs12041331 A-allele carriers had significantly increased risk of myocardial infarction compared with GG homozygotes (odds ratio, 2.03; 95% confidence interval, 1.01-4.09; P=0.048). CONCLUSION- Common genetic variation in PEAR1 may be a determinant of platelet response and cardiovascular events in patients on aspirin alone or in combination with clopidogrel. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00799396 and NCT00370045.

Dysfunction of circulating endothelial progenitor cells in type 1 diabetic rats with diabetic retinopathy

PURPOSE

To investigate the role of endothelial progenitor cell (EPC) in the pathogenesis of diabetic retinopathy (DR) in streptozotocin (STZ)-induced type 1 diabetes mellitus (T1DM) rats.

METHODS

A total of 160 male Wistar rats (12 weeks old; 250-350 g) were randomly assigned into four groups (n = 40 for each), including control (group 1, no treatment), T1DM1 (group 2, 1 month after 50 mg/kg of STZ, single i.p.), T1DM3 (group 3, 3 months after 50 mg/kg of STZ, single i.p.), T1DM6 (group 4, 6 months after 50 mg/kg of STZ, single i.p.). Enumeration of circulating EPC from peripheral blood was measured by flow cytometry. EPC from bone marrow of rats was cultured in vitro to evaluate its function of proliferation, adhesion, and migration activities. Plasma levels of vascular endothelial growth factor (VEGF) and nitric oxide (NO) were measured by enzyme-linked immunosorbent assay (ELISA). Retinal sections were imaged by light microscopy and a transmission electron microscope (TEM).

RESULTS

The numbers of circulating EPC were significantly decreased in diabetic groups compared with the control group. Impaired proliferation, adhesion, and migratory activities of cultured EPC were observed in diabetic groups. There were significantly higher levels of plasma VEGF but lower levels of plasma NO in diabetic groups than those in non-diabetic controls. The significantly reduced thickness and obvious disorganized retinal cell layers were seen in T1DM DR rats. In the diabetic groups, we also found that T1DM rats developed telangiectatic vessels, vacuolar degeneration of ganglion cells, and thickened capillary basement membrane with capillary lumen stenosis in the retina. Significantly raised EPC numbers during DR formation and progression were also found.

CONCLUSIONS

The reduced numbers and impaired function of circulating EPC may contribute to the pathogenesis of DR in T1DM rats.

Gender disparities in the presentation, management and outcomes of acute coronary syndrome patients: data from the 2nd Gulf Registry of Acute Coronary Events (Gulf RACE-2)

Background

Gender-related differences in mortality of acute coronary syndrome (ACS) have been reported. The extent and causes of these differences in the Middle-East are poorly understood. We studied to what extent difference in outcome, specifically 1-year mortality are attributable to demographic, baseline clinical differences at presentation, and management differences between female and male patients.

Methodology/Principal Findings

Baseline characteristics, treatment patterns, and 1-year mortality of 7390 ACS patients in 65 hospitals in 6 Arabian Gulf countries were evaluated during 2008–2009, as part of the 2nd Gulf Registry of Acute Coronary Events (Gulf RACE-2). Women were older (61.3±11.8 vs. 55.6±12.4; P<0.001), more overweight (BMI: 28.1±6.6 vs. 26.7±5.1; P<0.001), and more likely to have a history of hypertension, hyperlipidemia or diabetes. Fewer women than men received angiotensin-converting enzyme inhibitors (ACE), aspirin, clopidogrel, beta blockers or statins at discharge. They also underwent fewer invasive procedures including angiography (27.0% vs. 34.0%; P<0.001), percutaneous coronary intervention (PCI) (10.5% vs. 15.6%; P<0.001) and reperfusion therapy (6.9% vs. 20.2%; P<0.001) than men. Women were at higher unadjusted risk for in-hospital death (6.8% vs. 4.0%, P<0.001) and heart failure (HF) (18% vs. 11.8%, P<0.001). Both 1-month and 1-year mortality rates were higher in women than men (11% vs. 7.4% and 17.3% vs. 11.4%, respectively, P<0.001). Both baseline and management differences contributed to a worse outcome in women. Together these variables explained almost all mortality disparities.

Conclusions/Significance

Differences between genders in mortality appeared to be largely explained by differences in prognostic variables and management patterns. However, the origin of the latter differences need further study.

A process-based review of mouse models of pulmonary hypertension

Genetically modified mouse models have unparalleled power to determine the mechanisms behind different processes involved in the molecular and physiologic etiology of various classes of human pulmonary hypertension (PH). Processes known to be involved in PH for which there are extensive mouse models available include the following: (1) Regulation of vascular tone through secreted vasoactive factors; (2) regulation of vascular tone through potassium and calcium channels; (3) regulation of vascular remodeling through alteration in metabolic processes, either through alteration in substrate usage or through circulating factors; (4) spontaneous vascular remodeling either before or after development of elevated pulmonary pressures; and (5) models in which changes in tone and remodeling are primarily driven by inflammation. PH development in mice is of necessity faster and with different physiologic ramifications than found in human disease, and so mice make poor models of natural history of PH. However, transgenic mouse models are a perfect tool for studying the processes involved in pulmonary vascular function and disease, and can effectively be used to test interventions designed against particular molecular pathways and processes involved in disease.

Directional atherectomy of a heavy calcified axillary artery stenosis inducing critical hand ischemia

The presence of a severe calcified peripheral artery lesion is responsible for a poor response to balloon dilation, due to significant acute vessel recoil and frequent flow-limiting dissections requiring stent implantation. This possibility could be associated with very high compression and/or fracture rates particularly in cases of lesion located at the mobile joints. In this setting directional atherectomy offers the theoretical advantages of eliminating stretch injury on arterial walls and reducing the restenosis rate by direct plaque excision. In this report, we present a case of critical hand ischemia due to a heavily calcified axillary artery lesion managed by directional atherectomy and balloon angioplasty followed by immediate angiographic success and sustained clinical benefit up to 3 years of follow-up.

Association of adiponectin with blood pressure in healthy people

OBJECTIVE

With the increasing prevalence of diseases related to obesity, metabolic syndrome and its key player adiponectin are now attracting considerable attention. Hypoadiponectinaemia is reported to be a risk factor for hypertension and associated with endothelial dysfunction, which is closely related to complications of obesity such as hypertension. As there is limited information regarding serum adiponectin levels in normotensive people, we undertook the large-scale study to determine the association of adiponectin with blood pressure (BP) in mainly normotensive people.

DESIGN, PATIENTS AND MEASUREMENTS

In 21 100 Japanese adults (12 363 men and 8737 women) who had no apparent diseases, we examined the relationship between the serum adiponectin concentration and BP by performing a questionnaire survey, physical measurements and measurement of laboratory parameters including the serum adiponectin level.

RESULTS

Subjects with hypoadiponectinaemia had higher systolic and diastolic BPs as already reported. And interestingly, subjects with higher adiponectin had lower systolic and diastolic BP. According to linear regression analysis, adiponectin showed a significant negative correlation with systolic and diastolic BP independently of the other variables. Analysis of covariance according to adiponectin quintiles showed that systolic and diastolic BP in highest adiponectin quintile was significantly lower than in other quintiles.

CONCLUSIONS

This study revealed that there were significant trends toward lower systolic and diastolic BP with higher adiponectin not only in hypertensive people but also in normotensive people.

The protective effect of oxytocin on ischemia/reperfusion injury in rat urinary bladder

Oxytocin (OXY), a well-known nonapeptide, plays a crucial role in reproduction, and has effects on modulating the immune and inflammatory processes in living organisms as well. Recently it is also known as an antioxidant in several organs. The present study aims to demonstrate the protective effect of OXY against ischemia/reperfusion (I/R) injury in urinary bladder tissue. Abdominal aorta of rats, were clamped to perform urinary bladder ischemia. OXY (0.5 μg/kg) was injected intraperitoneally before ischemia in I/R+OXY group, whereas the vehicle solution was injected to I/R group. At the end of reperfusion, tissue samples from urinary bladder were processed for histochemical, ultrastructural and biochemical analysis. Tissue sections were stained by toluidine blue for mast cell counting and hematoxylin-eosin for histopathology. In addition, malondialdehyde (MDA) and glutathione (GSH) levels were determined biochemically. The results demonstrated that there was an extreme damage at urothelium, dilatation of intercellular junctions, inflammatory cell infiltration in I/R group. I/R+OXY group demonstrated a reduction in the severity of urinary bladder damage. According to mast cell counting results, both granulated and degranulated mast cells were decreased in I/R+OXY group compared to I/R group. The mean MDA level was higher in I/R group compared to control and lower in I/R+OXY group compared to I/R group. GSH level reduced in I/R group compared to the control and increased in I/R+OXY group compared to I/R group. In conclusion, oxytocin, as confirmed by histological evaluation and biochemical assays has a potential protective effect in the urinary bladder tissue against ischemia/reperfusion injury.

Focused transthoracic echocardiography by sports medicine physicians: measurements relevant to hypertrophic cardiomyopathy

OBJECTIVES

The purpose of this study was to investigate whether sports medicine physicians can use portable echocardiography to obtain measurements pertinent to hypertrophic cardiomyopathy.

METHODS

Thirty male collegiate athletes, aged 18 to 21 years, were prospectively enrolled. Focused portable echocardiography was performed by a board-certified sports medicine physician and a resident physician, followed by comprehensive echocardiography within 2 weeks by a registered diagnostic cardiac sonographer. A left parasternal long-axis view was acquired to measure 3 dimensions: (1) end-diastolic interventricular septal thickness (IVSd), (2) end-diastolic left ventricular internal diameter (LVIDd), and (3) end-diastolic left ventricular posterior wall thickness (LVPWd).

RESULTS

Intraclass correlation coefficients between the sports medicine physician and the sonographer were strong: 0.77 for IVSd, 0.73 for LVIDd, and 0.64 for LVPWd. Intraclass correlation coefficients between measurements by the resident physician and sonographer were strong to moderate: 0.61 for IVSd, 0.62 for LVIDd, and 0.63 for LVPWd. Across all 3 readers, intraclass correlation coefficient calculations were 0.77 for IVSd, 0.81 LVIDd, and 0.75 for LVPWd, which indicated strong inter-rater reliability.

CONCLUSIONS

Sports medicine physicians are able to obtain measurements relevant to the diagnosis of hypertrophic cardiomyopathy with focused portable echocardiography that are consistent with comprehensive echocardiography by a registered sonographer.