Molecular identity of the lateral lemniscus nuclei in the adult mouse brain

Introduction

The dorsal (DLL), intermediate (ILL), and ventral (VLL) lateral lemniscus nuclei are relay centers in the central auditory pathway of the brainstem, commonly referred to as the lateral lemniscus nuclei (LLN). The LLN are situated in the prepontine and pontine hindbrain, from rhombomeres 1 to 4, extending from the more rostral DLL to the caudal VLL, with the ILL lying in between. These nuclei can be distinguished morphologically and by topological and connectivity criteria, and here, we set out to further characterize the molecular nature of each LLN.

Methods

We searched in situ hybridization studies in the Allen Mouse Brain Atlas for genes differentially expressed along the rostrocaudal axis of the brainstem, identifying 36 genes from diverse functional families expressed in the LLN.

Results

Available information in the databases indicated that 7 of these 36 genes are either associated with or potentially related to hearing disorders.

Discussion

In conclusion, the LLN are characterized by specific molecular profiles that reflect their rostrocaudal organization into the three constituent nuclei. This molecular regionalization may be involved in the etiology of some hearing disorders, in accordance with previous functional studies of these genes.

Epidemiology and impact of frailty in patients with atrial fibrillation in Europe

BACKGROUND

Frailty is a medical syndrome characterised by reduced physiological reserve and increased vulnerability to stressors. Data regarding the relationship between frailty and atrial fibrillation (AF) are still inconsistent.

OBJECTIVES

We aim to perform a comprehensive evaluation of frailty in a large European cohort of AF patients.

METHODS

A 40-item frailty index (FI) was built according to the accumulation of deficits model in the AF patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry. Association of baseline characteristics, clinical management, quality of life, healthcare resources use and risk of outcomes with frailty was examined.

RESULTS

Among 10,177 patients [mean age (standard deviation) 69.0 (11.4) years, 4,103 (40.3%) females], 6,066 (59.6%) were pre-frail and 2,172 (21.3%) were frail, whereas only 1,939 (19.1%) were considered robust. Baseline thromboembolic and bleeding risks were independently associated with increasing FI. Frail patients with AF were less likely to be treated with oral anticoagulants (OACs) (odds ratio 0.70, 95% confidence interval 0.55-0.89), especially with non-vitamin K antagonist OACs and managed with a rhythm control strategy, compared with robust patients. Increasing frailty was associated with a higher risk for all outcomes examined, with a non-linear exponential relationship. The use of OAC was associated with a lower risk of outcomes, except in patients with very/extremely high frailty.

CONCLUSIONS

In this large cohort of AF patients, there was a high burden of frailty, influencing clinical management and risk of adverse outcomes. The clinical benefit of OAC is maintained in patients with high frailty, but not in very high/extremely frail ones.

Molecular Segmentation of the Spinal Trigeminal Nucleus in the Adult Mouse Brain

The trigeminal column is a hindbrain structure formed by second order sensory neurons that receive afferences from trigeminal primary (ganglionic) nerve fibers. Classical studies subdivide it into the principal sensory trigeminal nucleus located next to the pontine nerve root, and the spinal trigeminal nucleus which in turn consists of oral, interpolar and caudal subnuclei. On the other hand, according to the prosomeric model, this column would be subdivided into segmental units derived from respective rhombomeres. Experimental studies have mapped the principal sensory trigeminal nucleus to pontine rhombomeres (r) r2-r3 in the mouse. The spinal trigeminal nucleus emerges as a plurisegmental formation covering several rhombomeres (r4 to r11 in mice) across pontine, retropontine and medullary hindbrain regions. In the present work we reexamined the issue of rhombomeric vs. classical subdivisions of this column. To this end, we analyzed its subdivisions in an AZIN2-lacZ transgenic mouse, known as a reference model for hindbrain topography, together with transgenic reporter lines for trigeminal fibers. We screened as well for genes differentially expressed along the axial dimension of this structure in the adult and juvenile mouse brain. This analysis yielded genes from multiple functional families that display transverse domains fitting the mentioned rhombomeric map. The spinal trigeminal nucleus thus represents a plurisegmental structure with a series of distinct neuromeric units having unique combinatorial molecular profiles.

Multiple Regionalized Genes and Their Putative Networks in the Interpeduncular Nucleus Suggest Complex Mechanisms of Neuron Development and Axon Guidance

The interpeduncular nucleus (IPN) is a highly conserved limbic structure in the vertebrate brain, located in the isthmus and rhombomere 1. It is formed by various populations that migrate from different sites to the distinct domains within the IPN: the prodromal, rostral interpeduncular, and caudal interpeduncular nuclei. The aim here was to identify genes that are differentially expressed across these domains, characterizing their putative functional roles and interactions. To this end, we screened the 2,038 genes in the Allen Developing Mouse Brain Atlas database expressed at E18.5 and we identified 135 genes expressed within the IPN. The functional analysis of these genes highlighted an overrepresentation of gene families related to neuron development, cell morphogenesis and axon guidance. The interactome analysis within each IPN domain yielded specific networks that mainly involve members of the ephrin/Eph and Cadherin families, transcription factors and molecules related to synaptic neurotransmission. These results bring to light specific mechanisms that might participate in the formation, molecular regionalization, axon guidance and connectivity of the different IPN domains. This genoarchitectonic model of the IPN enables data on gene expression and interactions to be integrated and interpreted, providing a basis for the further study of the connectivity and function of this poorly understood nuclear complex under both normal and pathological conditions.

Netrin-1/DCC Signaling Differentially Regulates the Migration of Pax7, Nkx6.1, Irx2, Otp, and Otx2 Cell Populations in the Developing Interpeduncular Nucleus

The interpeduncular nucleus (IPN) is a hindbrain structure formed by three main subdivisions, the prodromal (Pro) domain located at the isthmus (Ist), and the rostral and caudal interpeduncular domains (IPR, IPC) within rhombomere 1 (r1). Various cell populations can be detected in the IPN through the expression of the Nkx6.1, Otp, Otx2, Pax7, and/or Irx2 transcription factors. These cell populations follow independent dorsoventral tangential and radial migratory routes targeting the ventral paramedian region of Ist and r1. Here we set out to examine the influence of the Netrin-1/DCC pathway on these migrations, since it is known to regulate other processes of neuronal migration in the brain. To this end, we analyzed IPN development in late gestational wild-type and DCC^-/- mice, using mainly in situ hybridization (ISH) to identify the cells expressing each of the aforementioned genes. We found that the migration of Nkx6.1 ⁺ and Irx2 ⁺ cells into the Pro domain was strongly disrupted by the loss of DCC, as occurred with the migration of Pax7 ⁺, Irx2 ⁺, and Otp ⁺ cells that would normally form the IPR. In addition, there was mild impairment of the migration of the Pax7 ⁺ and Otx2 ⁺ cells that form the IPC. These results demonstrate that the Netrin-1/DCC signaling pathway is involved in the migration of most of the IPN populations, mainly affecting those of the Pro and IPR domains of this nucleus. There are psychiatric disorders that involve the medial habenula (mHb)-IPN system, so that this experimental model could provide a basis to study their neurodevelopmental etiology.

Top Common Differentially Expressed Genes in the Epileptogenic Nucleus of Two Strains of Rodents Susceptible to Audiogenic Seizures: WAR and GASH/Sal

The Wistar Audiogenic Rat (WAR) and the Genetic Audiogenic Seizure Hamster from Salamanca (GASH/Sal) strains are audiogenic epilepsy models, in which seizures are triggered by acoustic stimulation. These strains were developed by selective reproduction and have a genetic background with minimal or no variation. In the current study, we evaluated the transcriptome of the inferior colliculus, the epileptogenic nucleus, of both audiogenic models, in order to get insights into common molecular aspects associated to their epileptic phenotype. Based on GASH/Sal RNA-Seq and WAR microarray data, we performed a comparative analysis that includes selection and functional annotation of differentially regulated genes in each model, transcriptional evaluation by quantitative reverse transcription PCR of common genes identified in both transcriptomes and immunohistochemistry. The microarray data revealed 71 genes with differential expression in WAR, and the RNA-Seq data revealed 64 genes in GASH/Sal, showing common genes in both models. Analysis of transcripts showed that Egr3 was overexpressed in WAR and GASH/Sal after audiogenic seizures. The Npy, Rgs2, Ttr, and Abcb1a genes presented the same transcriptional profile in the WAR, being overexpressed in the naïve and stimulated WAR in relation to their controls. Npy appeared overexpressed only in the naïve GASH/Sal compared to its control, while Rgs2 and Ttr genes appeared overexpressed in naïve GASH/Sal and overexpressed after audiogenic seizure. No statistical difference was observed in the expression of Abcb1a in the GASH/Sal model. Compared to control animals, the immunohistochemical analysis of the inferior colliculus showed an increased immunoreactivity for NPY, RGS2, and TTR in both audiogenic models. Our data suggest that WAR and GASH/Sal strains have a difference in the timing of gene expression after seizure, in which GASH/Sal seems to respond more quickly. The transcriptional profile of the Npy, Rgs2, and Ttr genes under free-seizure conditions in both audiogenic models indicates an intrinsic expression already established in the strains. Our findings suggest that these genes may be causing small changes in different biological processes involved in seizure occurrence and response, and indirectly contributing to the susceptibility of the WAR and GASH/Sal models to audiogenic seizures.

Impact of Diabetes Mellitus and Frailty on Long-Term Outcomes in Elderly Patients with Acute Coronary Syndromes

OBJECTIVES

Diabetes mellitus (DM) and frailty are common in older patients with acute coronary syndromes (ACS). No data exists about its prognostic impact on long-term outcomes and their possible interaction in this setting.

DESIGN

Observational prospective study.

SETTING

Multicenter registry conducted in 44 hospitals in Spain.

PARTICIPANTS

Consecutive patients with ACS aged 80≥years.

MEASUREMENTS

A comprehensive geriatric evaluation was performed during hospitalization, including frailty assessment by the FRAIL score. The impact of DM and frailty on the incidence of mortality/readmission at 24 months was analysed by a Cox regression model.

RESULTS

A total of 498 patients were included (mean age 84.3 years). Prevalence of previous DM was 199/498 (40.0%). The rate of frail patients was 135/498 (27.1%). The incidence of mortality/readmission was higher frail patients (HR 2.49) (both p<0.001). In contrast, DM was not significantly associated to a higher rate of outcomes (HR 1.23, p=0.060) in the whole cohort. Among non-frail patients, patients with DM had a similar incidence of mortality or readmission (p=0.959). In contrast, among frail patients, DM was significantly associated with a higher incidence of events (HR 1.51, p=0.034).

CONCLUSIONS

Unlike frailty status, DM was not associated to poorer long-term outcome in elderly patients with ACS. Among frail patients the presence of DM seems to provide additional prognostic information.

Efficacy and safety of peri-procedural bridging therapy with low molecular weight heparin in atrial fibrillation patients under vitamin K antagonists

BACKGROUND

The clinical effect of peri-operative bridging therapy in atrial fibrillation (AF) patients remains unclear given that it may increase bleeding risk without providing significant benefits. We aimed to investigate peri-procedural events in relation to peri-operative use of bridging therapy in AF patients under Vitamin K Antagonists (VKAs).

METHODS

We included AF patients stable the previous 6 months on VKAs. During a median follow-up of 6.5 years (IQR 4.3-7.9), we recorded all invasive procedures and the peri-operative clinical management. All peri-procedural events (ischaemic stroke/transient ischaemic attack/systemic embolism, clinically relevant non-major bleeding and major bleeding) and severe peri-procedural events (ischaemic stroke/transient ischaemic attack/systemic embolism and major bleeding) suffered until the 30-days post-intervention period were recorded.

RESULTS

We included 1361 patients (48.7% male, median age 76 [IQR 71-81] years). There were 1100 (70.9%) procedures performed using bridging therapy. The rate of any (4.5% vs. 0.7%, P < 0.001) and severe (2.3% vs. 0.0%, P = 0.002) peri-procedural events were higher in patients receiving bridging therapy. Adjusted logistic regressions demonstrated that the bleeding risk of the procedure was related with higher risk of severe peri-procedural events (OR 3.51, 95% CI 1.54-8.01) and peri-procedural events (OR 2.77, 95% CI 1.56-4.91). Importantly, the use of bridging therapy was also independently associated with higher risk of any peri-procedural events (OR 4.32, 95% CI 1.28-14.51).

CONCLUSIONS

In this study including AF patients under VKA therapy, the use of bridging therapy as part of the clinical management during an invasive procedure was independently associated with higher risk of any peri-procedural event.

Modeling and simulation of different and representative engineering problems using Network Simulation Method

Mathematical models simulating different and representative engineering problem, atomic dry friction, the moving front problems and elastic and solid mechanics are presented in the form of a set of non-linear, coupled or not coupled differential equations. For different parameters values that influence the solution, the problem is numerically solved by the network method, which provides all the variables of the problems. Although the model is extremely sensitive to the above parameters, no assumptions are considered as regards the linearization of the variables. The design of the models, which are run on standard electrical circuit simulation software, is explained in detail. The network model results are compared with common numerical methods or experimental data, published in the scientific literature, to show the reliability of the model.

Do physicians correctly calculate thromboembolic risk scores? A comparison of concordance between manual and computer-based calculation of CHADS2 and CHA2 DS2 -VASc scores

BACKGROUND

Clinical risk scores, CHADS2 and CHA2 DS2 -VASc scores, are the established tools for assessing stroke risk in patients with atrial fibrillation (AF).

AIM

The aim of this study is to assess concordance between manual and computer-based calculation of CHADS2 and CHA2 DS2 -VASc scores, as well as to analyse the patient categories using CHADS2 and the potential improvement on stroke risk stratification with CHA2 DS2 -VASc score.

METHODS

We linked data from Atrial Fibrillation Spanish registry FANTASIIA. Between June 2013 and March 2014, 1318 consecutive outpatients were recruited. We explore the concordance between manual scoring and computer-based calculation. We compare the distribution of embolic risk of patients using both CHADS2 and CHA2 DS2 -VASc scores

RESULTS

The mean age was 73.8 ± 9.4 years, and 758 (57.5%) were male. For CHADS2 score, concordance between manual scoring and computer-based calculation was 92.5%, whereas for CHA2 DS2 -VASc score was 96.4%. In CHADS2 score, 6.37% of patients with AF changed indication on antithrombotic therapy (3.49% of patients with no treatment changed to need antithrombotic treatment and 2.88% of patients otherwise). Using CHA2 DS2 -VASc score, only 0.45% of patients with AF needed to change in the recommendation of antithrombotic therapy.

CONCLUSION

We have found a strong concordance between manual and computer-based score calculation of both CHADS2 and CHA2 DS2 -VASc risk scores with minimal changes in anticoagulation recommendations. The use of CHA2 DS2 -VASc score significantly improves classification of AF patients at low and intermediate risk of stroke into higher grade of thromboembolic score. Moreover, CHA2 DS2 -VASc score could identify 'truly low risk' patients compared with CHADS2 score.

Expression patterns of Irx genes in the developing chick inner ear

The vertebrate inner ear is a complex three-dimensional sensorial structure with auditory and vestibular functions. The molecular patterning of the developing otic epithelium creates various positional identities, consequently leading to the stereotyped specification of each neurosensory and non-sensory element of the membranous labyrinth. The Iroquois (Iro/Irx) genes, clustered in two groups (A: Irx1, Irx2, and Irx4; and B: Irx3, Irx5, and Irx6), encode for transcriptional factors involved directly in numerous patterning processes of embryonic tissues in many phyla. This work presents a detailed study of the expression patterns of these six Irx genes during chick inner ear development, paying particular attention to the axial specification of the otic anlagen. The Irx genes seem to play different roles at different embryonic periods. At the otic vesicle stage (HH18), all the genes of each cluster are expressed identically. Both clusters A and B seem involved in the specification of the lateral and posterior portions of the otic anlagen. Cluster B seems to regulate a larger area than cluster A, including the presumptive territory of the endolymphatic apparatus. Both clusters seem also to be involved in neurogenic events. At stages HH24/25-HH27, combinations of IrxA and IrxB genes participate in the specification of most sensory patches and some non-sensory components of the otic epithelium. At stage HH34, the six Irx genes show divergent patterns of expression, leading to the final specification of the membranous labyrinth, as well as to cell differentiation.

Involvement of the -420C>G RETN polymorphism in myocardial fibrosis in patients with hypertrophic cardiomyopathy

AIMS

Hypertrophic cardiomyopathy (HCM) is characterized by left ventricular hypertrophy and fibrosis. HCM is an autosomal-dominant disease caused by more than 400 mutations in sarcomeric genes. Changes in nonsarcomeric genes contribute to its phenotypic heterogeneity. Cardiac fibrosis can be studied using late gadolinium enhancement (LGE) cardiac magnetic resonance imaging. We evaluated the potential role of two polymorphisms in nonsarcomeric genes on interstitial fibrosis in HCM.

MATERIALS AND METHODS

Two polymorphisms in nonsarcomeric genes [ACE (deletion of 287 bp in the 16th intron) and RETN (-420C>G)] were analysed in 146 HCM patients. Cardiac fibrosis was assessed using LGE to determine the number of affected segments.

RESULTS

Allelic frequencies in ACE and RETN polymorphisms were consistent with the Hardy-Weinberg equilibrium (both P > 0.05). We found that the presence of the polymorphic allele in the -420C>G RETN polymorphism was independently associated with the number of affected segments of LGE (P = 0.038). Increased circulating resistin concentration, measured by enzyme-linked immunosorbent assay, was associated with a higher degree of cardiac fibrosis. Myocardial fibrosis, assessed by Masson's trichrome staining, was associated with the -420C>G RETN polymorphism in 46 tissue samples obtained by septal myectomy (P = 0.044).

CONCLUSIONS

The -420C>G RETN polymorphism was independently associated with the degree of cardiac fibrosis, assessed by LGE, in patients with HCM. In addition, there was an association between the polymorphism and the circulating resistin levels as well as with myocardial fibrosis in tissues obtained by myectomy. Investigating the physiological implication of the RETN polymorphism in HCM in combination with the use of imaging technologies might help to establish the severity of disease in patients with HCM.

Crypto-rhombomeres of the mouse medulla oblongata, defined by molecular and morphological features

The medulla oblongata is the caudal portion of the vertebrate hindbrain. It contains major ascending and descending fiber tracts as well as several motor and interneuron populations, including neural centers that regulate the visceral functions and the maintenance of bodily homeostasis. In the avian embryo, it has been proposed that the primordium of this region is subdivided into five segments or crypto-rhombomeres (r7-r11), which were defined according to either their parameric position relative to intersomitic boundaries (Cambronero and Puelles, in J Comp Neurol 427:522-545, 2000) or a stepped expression of Hox genes (Marín et al., in Dev Biol 323:230-247, 2008). In the present work, we examine the implied similar segmental organization of the mouse medulla oblongata. To this end, we analyze the expression pattern of Hox genes from groups 3 to 8, comparing them to the expression of given cytoarchitectonic and molecular markers, from mid-gestational to perinatal stages. As a result of this approach, we conclude that the mouse medulla oblongata is segmentally organized, similarly as in avian embryos. Longitudinal structures such as the nucleus of the solitary tract, the dorsal vagal motor nucleus, the hypoglossal motor nucleus, the descending trigeminal and vestibular columns, or the reticular formation appear subdivided into discrete segmental units. Additionally, our analysis identified an internal molecular organization of the migrated pontine nuclei that reflects a differential segmental origin of their neurons as assessed by Hox gene expression.

The optimal management of patients on oral anticoagulation undergoing coronary artery stenting. The 10th Anniversary Overview

Even 10 years after the first appearance in the literature of articles reporting on the management of patients on oral anticoagulation (OAC) undergoing percutaneous coronary intervention with stent (PCI-S), this issue is still controversial. Nonetheless, some guidance for the everyday management of this patient subset, accounting for about 5-8 % of all patients referred for PCI-S, has been developed. In general, a period of triple therapy (TT) of OAC, with either vitamin K-antagonists (VKA) or non-vitamin K-antagonist oral anticoagulants (NOAC), aspirin, and clopidogrel is warranted, followed by the combination of OAC, and a single antiplatelet agent for up to 12 months, and then OAC alone. The duration of the initial period of TT is dependent on the individual risk of thromboembolism, and bleeding, as well as the clinical context in which PCI-S is performed (elective vs acute coronary syndrome), and the type of stent implanted (bare-metal vs drug-eluting). In this article, we aim to provide a comprehensive, at-a-glance, overview of the management strategies, which are currently suggested for the peri-procedural, medium-term, and long-term periods following PCI-S in OAC patients. While acknowledging that most of the evidence has been obtained from patients on OAC because of atrial fibrillation, and with warfarin being the most frequently used VKA, we refer in this overview to the whole population of OAC patients undergoing PCI-S. We refer to the whole population of patients on OAC undergoing PCI-S also when OAC is carried out with NOAC rather than VKA, pointing out, when appropriate, the particular management issues.

Prognostic value of two polymorphisms in non-sarcomeric genes for the development of atrial fibrillation in patients with hypertrophic cardiomyopathy

BACKGROUND

Several non-sarcomeric genes have been postulated to act as modifiers in the phenotypic manifestations of hypertrophic cardiomyopathy (HCM). The development of atrial fibrillation (AF) in HCM has adverse prognostic implications with increased thromboembolism and functional class impairment.

AIM

We tested the hypothesis that 2 non-sarcomeric genes [CYP11B2 (-344T>C) and COL1A1 (2046G>T)] are associated with the development of AF.

DESIGN

Prospective study.

METHODS

Two polymorphisms in non-sarcomeric genes [CYP11B2 (-344T>C) and COL1A1 (2046G>T)] were analysed in 159 HCM patients (49.3 ± 14.9 years, 70.6% male) and 136 controls. All subjects were clinically stable and in sinus rhythm at entry in the study, without ischemic heart disease or other significant co-morbidities that could mask the effect of the analysed polymorphisms (i.e. previous AF). Thirty-nine patients (24.4%) developed AF during a median follow-up of 49.5 months.

RESULTS

Patients with the -344T>C polymorphism in CYP11B2 gene had a higher risk for AF development [HR: 3.31 (95% CI 1.29-8.50); P = 0.008]. In a multivariate analysis, the presence of the C allele in CYP11B2 gene [HR: 3.02 (1.01-8.99); P = 0.047], previous AF [HR: 2.81 (1.09-7.23); P = 0.033] and a left atrial diameter of ≥42 mm [HR: 2.69 (1.01-7.18); P = 0.048] were independent predictors of AF development. The presence of the polymorphic allele was associated with higher aldosterone serum levels.

CONCLUSION

We have shown for the first time that the CYP11B2 polymorphism is an independent predictor for AF development in HCM patients. This highlights the importance of non-sarcomeric genes in the phenotypic heterogeneity of HCM. The association with higher aldosterone serum levels could relate to greater fibrosis and cardiac remodelling.

Biomarkers in atrial fibrillation: an overview

Atrial fibrillation (AF) confers a raised risk of stroke and death, and this risk of adverse events is increased by the coexistence of other cardiovascular risk factors. The pathophysiology of AF is complex, involving the role of inflammation, structural remodelling with apoptosis, inflammation or fibrosis. These changes confer a prothrombotic or hypercoagulable state in this arrhythmia. Despite being easy to use for decision-making concerning oral anticoagulant therapy in AF, clinical risk scores used for stratification have shown modest capability in predicting thromboembolic events, and biomarkers may improve our identification of 'high risk' patients. Biomarkers, whether measured in the peripheral blood, urine or imaging-based may improve our knowledge of the pathophysiology of AF. Importantly these biomarkers could help in the assessment of AF prognosis. The aim of this review was to summarise the published data about biomarkers studied in AF, with focus on data from randomised prospective clinical trials and large community-based cohorts. We will also review the application of these biomarkers to prognosis on the main schemes used to help stratify risk in AF.

Interleukin-6 as a predictor of cardiovascular events in troponin-negative non-ST elevation acute coronary syndrome patients

AIM

Risk stratification in acute coronary syndrome without ST-segment elevation (NSTE-ACS) and troponin-negative remains a challenge. We evaluated the value of interleukin-6 (IL-6) and amino-terminal pro-B-type natriuretic peptide (NT-proBNP) in the prognosis assessment of low-moderate risk NSTE-ACS and troponin-negative, and whether these biomarkers could improve the predictive performance of the established thrombolysis in myocardial infarction (TIMI) risk score.

METHODS

A total of 212 low-moderate risk patients with NSTE-ACS and troponin-negative were prospectively studied. Clinical follow up at 6 months was performed for adverse endpoints.

RESULTS

A total of 28 patients (13.5%) presented adverse clinical events. Those with adverse clinical events were associated with higher levels of IL-6 [8.58 (5.13-20.95) ng/l vs. 6.12 (4.16-9.14) ng/l, p = 0.043] and NT-proBNP [275.3 (108.6-548.2) ng/l vs. 126.8 (55.97-430.20) ng/l, p = 0.046]. In moderate risk group, we observed a higher event rate in patients with troponin-negative but elevated levels of IL-6 (p = 0.024). Only elevated IL-6 (> 12.40 ng/l) was an independent predictor of adverse outcomes [hazard ratios: 3.62, 95% confidence interval (CI) 1.69-7.75, p = 0.001]. The addition of IL-6 and history of ischaemic heart disease (IHD) to TIMI risk score significantly improved both the discrimination (integrated discrimination improvement, p = 0.003) and reclassification (Clinical Net reclassification improvement, p = 0.010) of the model for adverse events.

CONCLUSIONS

Interleukin-6 is an independent predictor of adverse events in low-moderate risk patients with NSTE-ACS and troponin-negative. Its use identifies a higher risk population in moderate-risk patients. This provides together with history of IHD a better discrimination and reclassification beyond that achieved with clinical risk variables from TIMI risk score in these patients.

Neurological manifestations of cardiac myxoma: experience in a referral hospital

INTRODUCTION

Cardiac myxoma is an important but uncommon cause of stroke in younger patients. Few published case series analyse the frequency and clinical presentation of neurological complications in patients with myxoma.

OBJECTIVE

To list all neurological complications from cardiac myxoma recorded in our hospital in the past 28 years.

PATIENTS AND METHODS

We retrospectively reviewed the neurological manifestations of cardiac myxoma in patients treated in our hospital between December 1983 and March 2012.

RESULTS

Of the 36 patients with cardiac myxoma, 8 (22%) presented neurological manifestations. Half were women and mean age of patients was 52.4 ± 11.6 years. Sudden-onset hemiparesis was the most frequent neurological symptom (63%). Established ischaemic stroke was the most common clinical manifestation (75%), followed by transient ischemic attack. The most commonly affected territory corresponded to the middle cerebral artery. Myxoma was diagnosed by echocardiography in all cases. Mean myxoma size was 4.1cm and most of the tumours (63%) had a polypoid surface. All tumours were successfully removed by surgery. There were no in-hospital deaths.

CONCLUSIONS

Cardiac myxomas frequently present with neurological symptoms, especially ischaemic events (established stroke or transient ischaemic attack), in younger patients with no cardiovascular risk factors. The anterior circulation is more frequently affected, especially the middle cerebral artery. Echocardiography can facilitate prompt diagnosis and early treatment of the lesion.

High sensitivity cardiac troponin T and interleukin-6 predict adverse cardiovascular events and mortality in anticoagulated patients with atrial fibrillation

There are limited data on the prognostic role of biomarkers in anticoagulated patients with atrial fibrillation (AF). We evaluated the prognostic value of high sensitivity TnT (hsTnT) and high-sensitivity interleukin-6 (hsIL6) in a large cohort of AF patients taking oral anticoagulant therapy (OAC) as both biomarkers have been associated with adverse cardiovascular events.

METHODS

We studied 930 patients (51% male; median age 76) with permanent/ paroxysmal AF who were stabilized (for at least 6 months) on OAC (INRs 2.0-3.0). Plasma hsTnT and hsIL6 levels were quantified by electrochemiluminescense immunoassay at baseline. Patients were followed-up for up to 2 years, and adverse events (thrombotic and vascular events, mortality and major bleeding) were recorded.

RESULTS

At follow-up, 96 patients (3.97%/year) died whilst 107 had an adverse cardiovascular event (3.14%/year). On multivariate analysis, high hsTnT and high hsIL6 remained significantly associated with prognosis even after adjusting for CHADS2 score: HR 2.21 (1.46-3.35, P<0.001) for high hsTnT and 1.97 (1.29-3.02, P=0.002) for high hsIL6, for adverse cardiovascular events. For all-cause mortality, the HRs were 1.79 (1.13-2.83, P=0.013) and 2.48 (1.60-3.85, P<0.001), respectively. The integrated discrimination index (IDI) values of clinical scores (CHADS2 and CHA2 DS2-VASc) were improved by the addition of hsTnT and/or hsIL6 (all P<0.05).

CONCLUSION

In a large 'real world' cohort of anticoagulated AF patients, both hsTnT and hsIL6 levels provided prognostic information that was complementary to clinical risk scores for prediction of long-term cardiovascular events and death, suggesting that these biomarkers may potentially be used to refine clinical risk stratification in AF.

New perspectives in antiplatelet therapy

Platelet activation is a complex mechanism of response to vascular injury and atherothrombotic disease, leading to thrombus formation. A wide variety of surface receptors -integrins, leucine-rich family receptors, G protein coupled receptors, tyrosine kinase receptors- and intraplatelet molecules support and regulate platelet activation. They are potential targets of antiplatelet therapy for the prevention and treatment of arterial thrombosis. Despite the overall clinical benefit of established antiplatelet drugs targeting cyclooxigenase-1 (COX-1), glycoprotein integrin αIIbβ3, and the purinergic P2Y(12) receptor of adenosine diphosphate, a significant proportion of treated patients continue to experience recurrent ischaemic events. This may be in partly attributed to insufficient inhibition of platelet activation. In addition, it should not be underestimated that these drugs are not immune from bleeding complications. The substantial progress in understating the regulation of platelet activation has played a key role in the development of novel antiplatelet agents. Current examples of drug under development and evaluation include: novel P2Y(12) receptor inhibitors (prasugrel, ticagrelor, cangrelor, and elinogrel), thrombin receptor PAR-1 antagonists (vorapaxar, atopaxar), new integrin glycoprotein IIb/IIIa inhibitors, and inhibitors targeting the thromboxane receptor (TP), phosphodiesterases, the collagen receptor glycoprotein VI, and intraplatelet signalling molecules. This review summarizes the mechanisms of action and current clinical evaluation of these novel antiplatelet agents.

Developmental expression pattern of Hspb8 mRNA in the mouse brain: analysis through online databases

Hspb8 is a member of the Hspb family of chaperone-like proteins. It is involved in several neural disorders such as Alzheimer's disease, amyotrophic lateral sclerosis, hereditary distal motor neuropathy, and Charcot-Marie-Tooth's disease. In this work, we aimed to characterize its expression pattern in the mouse brain, by using the information available at online databases of high-throughput in situ hybridization. Therefore, we downloaded and analyzed the image series from these databases showing Hspb8 mRNA expression from embryonic to adult and aging stages. In early gestational embryos, Hspb8 was expressed in the hippocampal anlagen and in the ventricular layer of rhombomere 4. At perinatal stages, there appeared transitory expression in the dentate gyrus and the cerebellar cortex. From perinatal to aging stages, the neurons of the mesencephalic trigeminal nucleus and cranial motor nuclei displayed stable and strong Hspb8 expression. Additionally, along these stages there was moderate and relatively homogenous expression in the anterodorsal thalamic, lateral mammillary, arcuate hypothalamic and medial habenular nuclei, and in the locus coeruleus. In its turn, the basal ganglia, cerebellar inner granular layer and diverse sensory and reticular formation nuclei of the hindbrain contained scattered cells with strong expression. In conclusion, Hspb8 mRNA is constitutively expressed in specific brain structures across ontogeny, so that eventually they could be affected by the malfunction or deregulation of this molecule.

Interactions between clopidogrel and proton pump inhibitors: a review of evidence

Clopidogrel is a thienopyridine, which inhibits the platelet P2Y adenosine diphosphate (ADP) receptor termed P2Y(12). It is taken as a prodrug that requires biotransformation to an active metabolite by cytochrome P450 (CYP) isoenzymes. In addition, esterases shunt the majority of clopidogrel to an inactive pathway, whilst the remaining prodrug requires two separate CYP-dependent oxidative steps. PPIs might diminish the antiplatelet effects and the clinical effectiveness of clopidogrel possibly through inhibition of CYP2C19 and CYP3A4 isoenzymes. Treatment with clopidogrel and aspirin decreases recurrent cardiovascular events after an acute coronary syndrome. However, an inherent increment of major bleeding is also associated with antiplatelet therapy, as well as dyspepsia with aspirin. Also, major bleeding has been associated with high risk for ischemic events and mortality. For this reason, a proton pump inhibitor (PPI) is often co-prescribed to reduce the risk of gastrointestinal tract bleeding, but its concomitant use might reduce the inhibitory effect of clopidogrel on platelet aggregation. Nevertheless, doubts exist about the possible interaction of concomitant PPI use that may reduce the inhibitory effect of clopidogrel on platelet aggregation. Indeed, there is some controversy with regard to the true risk of cardiovascular adverse events arising from a potential drug-drug interaction between clopidogrel and PPI. In this article, we will review the current status and controversies in relation to a possible interaction between clopidogrel and PPIs.

Multiple origins, migratory paths and molecular profiles of cells populating the avian interpeduncular nucleus

The interpeduncular nucleus (IP) is a key limbic structure, highly conserved evolutionarily among vertebrates. The IP receives indirect input from limbic areas of the telencephalon, relayed by the habenula via the fasciculus retroflexus. The function of the habenulo-IP complex is poorly understood, although there is evidence that in rodents it modulates behaviors such as learning and memory, avoidance, reward and affective states. The IP has been an important subject of interest for neuroscientists, and there are multiple studies about the adult structure, chemoarchitecture and its connectivity, with complex results, due to the presence of multiple cell types across a variety of subnuclei. However, the ontogenetic origins of these populations have not been examined, and there is some controversy about its location in the midbrain-anterior hindbrain area. To address these issues, we first investigated the anteroposterior (AP) origin of the IP complex by fate-mapping its neuromeric origin in the chick, discovering that the IP develops strictly within isthmus and rhombomere 1. Next, we studied the dorsoventral (DV) positional identity of subpopulations of the IP complex. Our results indicate that there are at least four IP progenitor domains along the DV axis. These specific domains give rise to distinct subtypes of cell populations that target the IP with variable subnuclear specificity. Interestingly, these populations can be characterized by differential expression of the transcription factors Pax7, Nkx6.1, Otp, and Otx2. Each of these subpopulations follows a specific route of migration from its source, and all reach the IP roughly at the same stage. Remarkably, IP progenitor domains were found both in the alar and basal plates. Some IP populations showed rostrocaudal restriction in their origins (isthmus versus anterior or posterior r1 regions). A tentative developmental model of the structure of the avian IP is proposed. The IP emerges as a plurisegmental and developmentally heterogeneous formation that forms ventromedially within the isthmus and r1. These findings are relevant since they help to understand the highly complex chemoarchitecture, hodology and functions of this important brainstem structure.

Left atrial remodelling in hypertrophic cardiomyopathy: relation with exercise capacity and biochemical markers of tissue strain and remodelling

BACKGROUND

Left atrial remodelling, assessed as left atrial volume (LAV), has been proposed as a good marker of left ventricular diastolic dysfunction. The aim of this study was to analyse the influence of LAV on exercise performance in hypertrophic cardiomyopathy (HCM), and in a subset of subjects, assess the relation of LAV and exercise performance to four biomarkers of disease pathophysiology: matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) (as indices of tissue remodelling), N-terminal portion of pro B-type natriuretic peptide (NT-pro-BNP) (associated with ventricular dysfunction) and C-reactive protein (CRP, an index of inflammation).

METHODS

We studied 75 consecutive HCM patients (aged 46 +/- 14 years, 56 men) where LAV was calculated assuming the ellipsoid model with two orthogonal planes. LAV was indexed to body surface area. Exercise capacity was evaluated by treadmill exercise test (symptom limited) and assessed with metabolic equivalent units (MET). Basal NT-pro-BNP and CRP levels were measured in 70 patients, whereas MMP-2 and TIMP-1 in 43 patients.

RESULTS

Enlarged LAV was observed in those patients with previous atrial fibrillation (p = 0.016). Mean LAV was greater in patients with impaired functional New York Heart Association (NYHA) class (p < 0.001). LAV correlated with age (Spearman, r: 0.28), higher maximal left ventricular wall thickness (r: 0.32) and raised E/A ratio (r: 0.37) (all p < 0.01). LAV was significantly correlated with NT-pro-BNP values (r: 0.34; p = 0.04), MMP-2 (r: 0.32; p = 0.034), CRP (r: 0.33; p = 0.005) and correlated inversely with MET units (r: -0.39; p < 0.01). In multivariate analysis, MET units were only associated with NT-pro-BNP (p = 0.002) and LAV (p = 0.010).

CONCLUSIONS

Enlarged LAV is associated with impaired functional NYHA class and inversely with treadmill exercise capacity. Enlarged LAV is also associated with NT-pro-BNP, MMP-2 and CRP, perhaps as markers of disease severity and tissue remodelling. Age, LAV and NT-pro-BNP are independent predictors of exercise performance.

Semichemical pulping of Miscanthus giganteus. Effect of pulping conditions on some pulp and paper properties

Miscanthus is an interesting raw material for pulp production, it is a high yield low maintenance plant with a high cellulose and hemicellulose content. Its semichemical pulp can be beneficial in paper for cardboard production process, which nowadays is usually made from secondary fibers, by increasing the mechanical properties of the paper produced. In this study, the influence of the percentage of NaOH used related to the dry Miscanthus weight, digestion time and refining time on some pulp and paper properties have been studied and compared with pulp obtained from commercial fluting paper (CF). Fiber size distribution of the Miscanthus pulp was found to contain a higher fines (less than 0.2mm) percentage than the CF pulp. Hand-sheets made from Miscanthus pulp showed better mechanical properties than the ones made with the CF pulp. CMT, RCT and CCT indexes were higher when using 100% Miscanthus pulp or mixtures of Miscanthus and CF pulp. The only property which worsened was Gurley porosity. Of the three operational variables changed, refining time exerts the most significant influence on the pulp and paper properties measured.

Relationship between bone quantitative ultrasound and mortality: a prospective study

In a cohort of 5,201 women [72.3 +/- 5.3 years] from 58 primary care centers in Spain, followed for three years, no relationship between heel QUS parameters and overall mortality was found. However, a significant relationship between a low speed of sound (SOS) and vascular mortality was observed.

INTRODUCTION

An inverse relationship between mortality and bone mineral density measured by dual-energy absorption densitometry or quantitative bone ultrasound (QUS) has been described. The aim of the present study was to test this relationship in the ECOSAP cohort, a 3-year prospective study designed to assess the ability of heel QUS and clinical risk factors to predict non-vertebral fracture risk in women over 64.

METHODS

A cohort of 5,201 women [72.3 +/- 5.3 years] was studied. QUS was assessed with the Sahara(R) bone sonometer. Women attended follow-up visits every 6 months. Physicians recorded if the patient died and cause of death. Hazard rates (HR) of all-cause and vascular mortality per one standard deviation reduction in QUS parameters were determined.

RESULTS

One hundred (1.9%) women died during a median of 36.1 months follow-up, for a total of 14,999 patient-years, 42 because of vascular events (both cardiovascular and cerebrovascular). After adjusting for age, none of the QUS variables showed statistically significant differences between the patients who died and the survivors. In the final multivariate model, adjusted for age, current thyroxine and hypoglycaemic drug use, chronic obstructive pulmonary disease and decreased visual acuity, SOS was marginally non-significant: (HR: 1.19; 0.97-1.45). However, each 1 SD reduction in SOS was associated with a 39% increase in vascular mortality (HR: 1.39; 1.15-1.66).

CONCLUSIONS

In our cohort, SOS was related with vascular mortality, but not overall mortality.

Insights into the role of microRNAs in cardiac diseases: from biological signalling to therapeutic targets

microRNAs have recently opened new pathways to explain gene expression and disease biology in many scenarios, including cardiac diseases. microRNAs are endogenous small non-coding RNAs that mediate post-transcriptional repression or messenger RNA degradation. By annealing to inexactly complementary sequences in the 3' untranslated region of the target messenger RNA, protein level is down-regulated. Several microRNAs appear to act cooperatively through multiple target sites in one gene and, conversely, most microRNAs can target several genes. miR-133 and miR-1 are specifically expressed in cardiac and skeletal muscle and control myogenesis, cardiac development, cardiac performance and cardiomyocyte hypertrophy (mainly by tuning transcription factors and other growth-related targets). They also modulate the expression of certain cardiac ion channels and related proteins with proarrhythmic effect. Besides them, other microRNAs have been shown to exert influence on the myocardial growth, the electrical balance and the angiogenesis processes that take place in the heart. Bioinformatics is a useful tool to identify potential targets of a given microRNA, although there is still substantial concern about their reliability. Experimental manipulation of microRNAs has provided a tantalizing basis to speculate that future research on microRNAs may yield important progress in the prevention of sudden cardiac death and in the treatment of cardiac heart failure. However, the final effect of the blockage of microRNAs in vivo remains unclear, since each of them can target hundreds of genes with different intensity. The era of the microRNAs in cardiovascular diseases has just started.

The impact of statin use on atrial fibrillation

The aim of the present systematic review is to present an overview of the evidence linking atrial fibrillation (AF), inflammation and oxidative stress, with emphasis on the potential of statins to decrease the incidence of different types of AF, including new-onset AF, after electrical cardioversion (EC) and after cardiac surgery. Observational and clinical trials have studied the impact of statin therapy on new-onset, post-EC or postoperative AF. Data from different observational trials have shown that treatment with statins significantly reduces the incidence of new-onset AF in the primary and secondary prevention. The data are insufficient to recommend the use of statins before EC. Finally, perioperative statin therapy may represent an important non-antiarrhythmic adjunctive therapeutic strategy for the prevention of postoperative AF.

Molecular and morphological changes in placenta and embryo development associated with the inhibition of polyamine synthesis during midpregnancy in mice

Polyamines play an essential role in murine development, as demonstrated by both gene ablation in ornithine decarboxylase (ODC)-deficient embryos and pharmacological treatments of pregnant mice. However, the molecular and cellular mechanisms by which ODC inhibition affects embryonic development during critical periods of pregnancy are mostly unknown. Our present results demonstrate that the contragestational effect of alpha-difluoromethylornithine (DFMO), a suicide inhibitor of ODC, when given at d 7-9 of pregnancy, is associated with embryo growth arrest and marked alterations in the development of yolk sac and placenta. Blood island formation as well as the transcript levels of embryonary globins alpha-like x chain and beta-like y-chain was markedly decreased in the yolk sac. At the placental level, abnormal chorioallantoic attachment, absence of the spongiotrophoblast layer and a deficient development of the labyrinthine zone were evident. Real-time RT-PCR analysis showed that transcript levels of the steroidogenic genes steroidogenic acute regulatory protein, 3beta-hydroxysteroid dehydrogenase VI, and 17alpha-hydroxylase were markedly decreased by DFMO treatment in the developing placenta at d 9 and 10 of pregnancy. Plasma values of progesterone and androstenedione were also decreased by DFMO treatment. Transcriptomic analysis also detected changes in the expression of several genes involved in placentation and the differentiation of trophoblastic lineages. In conclusion, our results indicate that ODC inhibition at d 8 of pregnancy is related to alterations in yolk sac formation and trophoblast differentiation, affecting processes such as vasculogenesis and steroidogenesis.

A multimarker risk stratification approach to non-ST elevation acute coronary syndrome: implications of troponin T, CRP, NT pro-BNP and fibrin D-dimer levels

INTRODUCTION

Biomarkers have emerged as interesting predictors of risk in non-ST elevation acute coronary syndromes (non-ST ACS). The aim of this study was to define the utility of the combined measurement of troponin T (TnT), C-reactive protein (CRP), NT pro-brain natriuretic peptide (NT pro-BNP) and D-dimer as biomarkers to predict adverse events.

METHODS

We included 358 consecutive patients admitted in two hospitals for non-ST ACS. Baseline measurements of TnT (associated with myocardial injury, positive, if > or =0.1 ng mL(-1)), CRP (a marker of inflammation), NT-proBNP (associated with left ventricular (dys)function) and fibrin D-dimer (and index of thrombogenesis) were performed. A positive CRP, NT-proBNP and D-dimer test was considered upper than the 75th percentile of our population. The risk for major events (death, new ACS, revascularization and heart failure) at 6 months' follow-up was analysed.

RESULTS

Troponin T, NT pro-BNP and CRP were predictors of adverse events in the multivariate analysis [hazards ratio (HR): 2.00 (1.30-3.07), P = 0.0016; HR: 2.27 (1.47-3.50), P = 0.0002; HR: 1.90 (1.24-2.92), P = 0.0034 respectively], but not D-dimer levels [HR: 1.26 (0.79-2.02), P = 0.337). After adjusting for baseline characteristics and electrocardiographic changes, multimarker risk approach was associated with adverse events at 6 months, especially with the presence of three positive biomarkers [HR 2.80 (95%CI 1.68-4.68), P < 0.001]. When we divided patients by risk groups [Thrombolysis in Myocardial Infarction (TIMI) risk score], patients with two or three elevated biomarkers had higher event rates [HR 2.59 (95% CI 1.37-4.91), P = 0.004].

CONCLUSION

A multimarker approach based on TnT, CRP and NT-proBNP provides added information to the TIMI risk score in terms of ACS prognosis at 6 months, with a worse outcome for those with two or three elevated biomarkers.

Patient compliance with alendronate, risedronate and raloxifene for the treatment of osteoporosis in postmenopausal women

OBJECTIVES

The aim was to investigate patient compliance with different osteoporosis medications commonly prescribed in clinical practice, to determine risk factors associated with discontinuation and to evaluate quality of life changes.

RESEARCH DESIGN AND METHODS

We conducted a 1-year observational study of patients of age > or = 60 years in a clinical setting at 917 sites in 10 European countries (Germany, Greece, UK, Sweden, Netherlands, Romania, Norway, Finland, Denmark, Estonia), Lebanon and South Africa. Demographic data, concomitant diseases, the reasons for intervention, educational, socio-economical status and disease knowledge were captured at baseline. Self-reported compliance, discontinuation data and health status were collected.

MAIN OUTCOME MEASURES

Out of 5198 patients, 3490 (67.1%) patients received 60 mg daily raloxifene (RAL), 452 (8.7%) 10 mg daily alendronate (AQD), 769 (14.8%) 70 mg once weekly alendronate (AQW) and 487 (9.4%) 5 mg daily risedronate (RIS). Among patients completing the study (4231, 81%), the percentage of patients with high compliance was 80% (RAL), 79% (AQD), 65% (AQW) and 76% (RIS). The discontinuation due to side effects was highest on AQW (7.0%), followed by AQD (6.4%), RAL (3.8%) and RIS (3.4%). The discontinuation-rate was higher for patients with a history of surgical menopause, increased age, lack of knowledge about medical prevention of osteoporosis and thin frame as a reason for intervention. The EQ-5D weighted index showed the highest improvement for RIS (0.13), followed by RAL (0.11), AQD (0.08) and AQW (0.07).

CONCLUSIONS

Data from this non-interventional observational study indicate moderate overall compliance and discontinuation rate with the prescribed osteoporosis medications.

Matrix metalloproteinase-1 and its inhibitor, TIMP-1, in systolic heart failure: relation to functional data and prognosis

BACKGROUND

Structural remodelling of left ventricle is a common feature in the progression of congestive heart failure (CHF). Matrix metalloproteinases (MMPs) have been directly implicated as they degrade extracellular proteins. To test the hypothesis that MMP-and its inhibitor, tissue type inhibitor of matrix metalloproteinases (TIMP-1), could be related to functional status and prognosis in CHF, we examined the relationship of MMP-1 and TIMP-1 to peak oxygen consumption (VO2) and peak minute ventilation/carbon dioxide production relationship (VE/VCO2), and assessed their prognostic value.

METHODS

We studied 50 patients with CHF, who were compared with 53 controls echocardiogram and ergoespirometry were performed, and serum levels of MMP-1 and TIMP-1 were assayed by ELISA. Patients were followed up for 17.5+/-8.9 months, and total mortality, readmissions for heart failure and cardiac transplantation were recorded.

RESULTS

Patients with CHF had lower levels of MMP-1 (P=0.027), and higher levels of TIMP-1 and TIMP-1/MMP-1 ratio (both P<0.01) than controls. TIMP-1 levels and the TIMP-1/MMP-1 ratio correlated negatively with peak VO2 (Spearman, r:-0.51; P=0.001 and r: -0.42; P=0.030, respectively). During the follow-up period, 23 patients (47.9%) suffered endpoints--these patients had higher baseline peak VE/VCO2 (P=0.001), TIMP-1 (P=0.004), and TIMP-1/MMP-1 ratio values (P=0.002), whereas MMP-1 levels were lower (P=0.027). On multivariate analysis, VE/VCO2, MMP-1 levels and age were the only variables independently related to prognosis (all P<0.05).

CONCLUSION

Poor functional capacity in CHF can be related to abnormal extracellular matrix turnover. Patients who suffered endpoints had more abnormal indices of matrix turnover, where MMP-1 levels showed independent prognostic value.

The genetic interaction between VKORC1 c1173t and calumenin a29809g modulates the anticoagulant response of acenocoumarol

BACKGROUND

The efficacy of oral anticoagulant therapy is largely conditioned by both environmental and genetic factors.

OBJECTIVES

To attempt to define the genetic profile involved in the response to this treatment.

PATIENTS AND METHODS

We selected 100 men younger than 75 years, with non-valvular atrial fibrillation, who started anticoagulation with acenocoumarol following the same protocol: 3 mg for three consecutive days. Then, doses were individually adjusted to achieve a steady International Normalized Ratio (INR). The basal plasma level and the level after 3 days were obtained, and the INR was determined. We studied five functional polymorphisms: FVII -323 Del/Ins, CYP2C*9, VKORC1 c1173t, calumenin (CALU) R4Q and CALU a29809g. The dose required for a steady INR was also recorded.

RESULTS

Only the VKORC1 genotype had significant impact on the efficacy of therapy. Carriers of the 1173t allele were significantly more sensitive to therapy for 3 days [INR 2.07 (1.59-2.87) vs. 1.74 (1.30-2.09); P = 0.015] and they needed lower acenocoumarol doses to stabilize their INR (15.8 +/- 5.6 vs. 19.5 +/- 6.0 mg week(-1); P = 0.004). Its effect was exacerbated by combination with the CALU a29809g polymorphism. Carriers of both variants (27% of the sample) achieved the highest INR [2.26 (1.70-3.32)] and required the lowest dose (14.1 +/- 5.1 mg week(-1)). This genetic profile was particularly relevant in patients with INR >or= 3.5 at the start of therapy (P = 0.005; odds ratio = 6.67, 95% confidence interval = 1.32-37.43).

CONCLUSIONS

Our results suggest that CALU a29809g might be a new genetic factor involved in the pharmacogenetics of anticoagulant therapy, and confirm that specific genetic profiles defined by different polymorphisms will determine the initial response and dose required to achieve a stable and safe INR.

Prediction of absolute risk of non-spinal fractures using clinical risk factors and heel quantitative ultrasound

The relationship between osteoporosis risk factors, bone quantitative ultrasound (QUS) and non-spinal fracture risk was estimated in a cohort of 5,201 postmenopausal women from Spain who were prospectively evaluated during three years. Several clinical risk factors and low heel QUS values were independently associated with non-spinal fracture risk.

INTRODUCTION

Low-trauma, non-spinal fractures are a growing source of morbidity and mortality in the elderly. The aim of the present study was to examine the association of heel quantitative ultrasound (QUS) and a series of osteoporosis and fracture risk factors, with incident low energy non-spinal fractures in a population of elderly women, and to incorporate them into fracture prediction models.

METHODS

5,201 women aged 65 or older were enrolled in a three-year cohort study. Participants completed an osteoporosis and fracture risk factors questionnaire. QUS was measured at the heel with a gel-coupled device. Cox-proportional hazard analyses were performed to evaluate the association with the first incident low-trauma non-spinal fracture.

RESULTS

Three hundred and eleven women (6.0%) sustained a total of 363 low-trauma fractures, including 133 forearm/wrist, 54 hip, 50 humerus, 37 leg and 17 pelvic fractures. For every standard deviation decrease in the quantitative ultrasound index, the adjusted hazard ratios (95% CI) for any non-vertebral, hip, forearm/wrist, and humerus fractures were 1.31 (1.15-1.49), 1.40 (1.01-1.95), 1.50 (1.19-1.89) and 1.35 (0.97-1.87), respectively. Similar results were observed with other QUS variables. The best predictive models indicated that age, a history of falls, a previous low-trauma fracture, a family history of fracture, a calcium intake from dairy products of less than 250 mg/day, and lower values of QUS parameters were independently associated with the risk of non-spinal fractures.

CONCLUSIONS

Both clinical risk factors and QUS are independent predictors of risk of fragility non-spinal fractures. A prediction algorithm using these variables was developed to estimate the absolute risk of non-spinal fractures in elderly women in Spain.

The expression of Scratch genes in the developing and adult brain

The Scratch genes belong to the Snail superfamily of zinc-finger transcription factors present in the metazoa, represented in mammals by the Scratch1 and Scratch2 genes. We have analyzed the expression of these genes in the brain of mice at developmental stages between 9.5 days-post-coitum to adulthood. Both genes are expressed in the mantle layer of the neuroepithelium at mid-gestational stages in all regions except for the region corresponding to the V2 interneuron column, which lacked Scratch2 transcripts. From perinatal to adult stages, the expression patterns of the two genes differ. Scratch1 remains strongly expressed in almost all brain regions, although it is not found in some ventral structures such as motor nuclei and hypothalamic regions. In contrast, Scratch2 expression progressively diminishes and virtually no expression can be detected in the adult brain. Nevertheless, strong expression of Scratch2 is retained in the postnatal cortical subventricular zone, in the inner part of the cerebellar external granular layer, and in the glial cells of the adult vomeronasal nerve.

Expression of Lrrn1 marks the prospective site of the zona limitans thalami in the early embryonic chicken diencephalon

An unknown chicken gene selected from a published substractive hybridization screen (GenBank Accession No. ; [Christiansen, J.H., Coles, E.G., Robinson, V., Pasini, A., Wilkinson, D.G., 2001. Screening from a subtracted embryonic chick hindbrain cDNA library: identification of genes expressed during hindbrain, midbrain and cranial neural crest development. Mech. Dev. 102, 119-133.]) was deemed of interest because of its dynamic pattern of expression across the forebrain and midbrain regions. A 528bp fragment cloned from early chick embryo cDNA and used for in situ hybridization corresponded to part of the 3' untranslated region of the chicken gene Leucine-rich repeat neuronal protein 1 (Lrrn1). The expression of this gene, mapped in the embryonic chick brain between stages HH10 and HH26, apparently preconfigures the zona limitans thalami site before overt formation of this boundary structure. Apart of colateral expression in the forebrain, midbrain and hindbrain basal plate, the most significant expression of Lrrn1 was found early on across the entire alar plate of midbrain and forebrain (HH10). This unitary domain soon divides at HH14 into a rostral part, across alar secondary prosencephalon and prospective alar prosomere 3 (prethalamus; caudal limit at the prospective zona limitans), and a caudal part in alar prosomere 1 (pretectum) and midbrain. The rostral forebrain domain later downregulates gradually most extratelencephalic signal of Lrrn1, but the rostral shell of zona limitans retains expression longer. Expression in the caudal alar domain also changes by downregulation within its pretectal subdomain. Caudally, the midbrain domain ends at the isthmo-mesencephalic junction throughout the studied period. Embryonic Lrrn1 signal also appears in the somites and in the otic vesicle.

Characterization of patients with an inadequate clinical outcome from osteoporosis therapy: the Observational Study of Severe Osteoporosis (OSSO)

BACKGROUND

Osteoporotic fractures remain a major public health problem. Currently available osteoporosis therapies significantly reduce the risk of fractures, but up to 50% of patients have an inadequate clinical outcome to therapy.

AIM

To describe the clinical and quality of life (QOL) of a study population meeting a proposed definition of inadequate clinical outcome to osteoporosis therapy, recruited for the Observational Study of Severe Osteoporosis (OSSO).

DESIGN

Cross-sectional, observational study.

METHODS

Post-menopausal women with osteoporosis (n = 2314) were divided into Group 1 (those who had previously experienced a fragility fracture despite osteoporosis drug therapy for at least 12 months) (n = 1309, 57%), or Group 2 (those who had previously discontinued osteoporosis drug therapy due to non-compliance or side-effects) (n = 1005; 43%). Baseline clinical characteristics, quality of life (QOL) and osteoporosis/falls risk factors were analysed.

RESULTS

The overall population had low BMD (mean +/- SD T-score at lumbar spine -3.1 +/- 1.1), and risk factors for fracture such as previous fractures (67.8%), family history (15.1%), and prolonged glucocorticoid use (17.5%). QOL was poor: total QUALEFFO and EQ-5D scores were 46.8 +/- 18.7, and 0.50 +/- 0.33, respectively. Patients in Group 1 had higher age and body mass index, fewer hours of exercise, more previous fragility fractures and falls, and poorer QOL scores.

DISCUSSION

Our definition of inadequate clinical outcome from osteoporosis drug therapy identifies a severe osteoporosis cohort with poor QOL and increased fracture risk. Using such a definition may lead to earlier recognition of inadequate clinical outcome to osteoporosis therapy, and improved interventions and results.

Ontogeny of tyrosine hydroxylase mRNA expression in mid- and forebrain: neuromeric pattern and novel positive regions

Tyrosine hydroxylase (TH) is the rate-limiting enzyme in the synthesis of catecholamines and, thus, critical in determining the catecholaminergic phenotype. In this study, we have examined the expression of TH mRNA by in situ hybridization in the embryonic mouse forebrain and midbrain and have mapped its localization according to the neuromeric pattern. We find that early in embryonic development, 10 to 12 days post coitum (dpc), TH mRNA is expressed in ample continuous regions of the neuroepithelium, extending across several neuromeres. However, from 12.5 dpc onward, the expression becomes restricted to discrete regions, which correspond to the dopaminergic nuclei (A8 to A15). In addition to these nuclei previously described, TH mRNA is also observed in regions that do not express this enzyme according to immunohistochemical studies. This difference in relation to protein expression pattern is consequent with the known posttranscriptional regulation of TH expression. The most representative example of a novel positive region is the conspicuous mRNA expression in both medial and lateral ganglionic eminences. This result agrees with reports describing the capacity of striatal stem cells (that is, located at the lateral ganglionic eminence) to become dopaminergic in vitro. Other regions include the isthmic mantle layer and the early floor plate of the midbrain-caudal forebrain. On the whole, the expression map we have obtained opens new perspectives for evolutionary/comparative studies, as well as for therapeutic approaches looking for potentially dopaminergic cells. Developmental Dynamics 234:709-717, 2005. (c) 2005 Wiley-Liss, Inc.

Mite allergen exposure, sensitisation and clinical symptoms in Valdivia, Chile

One hundred consecutive asthmatic paediatric patients were evaluated and skin tested with a battery of skin prick test reagents, including 8 different standardized house dust mite extracts. Asthma severity was graded according to the Global Initiative for Asthma (GINA) document in mild persistent (52 patients), moderate persistent (39) and severe persistent (9). Sixty patients had asthma and allergic rhinitis, 12 asthma and eczema, and 8 asthma, allergic rhinitis and eczema. The patient population was divided into 2 different socioeconomic groups (50 patients per group) based on a standardized, validated questionnaire. A dust sample was collected with an adapted vacuum cleaner from the mattress of each patient and analysed for Der p 1, Der f 1 and Der p 2 allergen content using monoclonal antibodies. Eighty patients were skin test positive to at least one mite species. All positive skin test patients were positive to Dermatophagoides pteronyssinus, 99% to D. farinae, 92% to Euroglyphus maynei, 80% to Lepidoglyphus destructor, 73% to Tyrophagus putrescientae, 72% to Blomia tropicalis; 70% to Acarus siro and 68% to Chortoglyphus arcuatus. All patients with severe persistent asthma had a positive skin test to mites, 85% in the moderate group, and 73% in the mild group (p < 0.01). 95% of patients with asthma and allergic rhinitis had a positive skin test to mites, 92% of patients with asthma and eczema and 100% of patients with asthma, allergic rhinitis and eczema; (p < 0.01). Mean Der p 1, Der f 1 and Der p 2 allergen concentrations were 18.3, 0.6 and 5.6 microg/g of mattress dust, respectively. Mean Der p 1 allergen levels in the middle-low socioeconomic group were significantly higher than in the middle high group (p < 0.01). There is a high rate of allergic sensitisation among pediatric asthmatic patients in Chile. More than one species are implicated, although sensitisation and exposure to D. pteronyssinus predominates. Mite allergic patients are exposed to high mite allergen concentrations, exceeding previously established risk levels for sensitisation and symptoms.

Plasma von Willebrand factor, soluble thrombomodulin, and fibrin D-dimer concentrations in acute onset non-rheumatic atrial fibrillation

OBJECTIVE

To investigate whether new onset acute atrial fibrillation (AF) of < 48 hours' duration creates a prothrombotic state in the absence of anticoagulation and to assess the evolution in research indices after spontaneous or pharmacological cardioversion.

METHODS

24 patients were recruited with first onset acute non-rheumatic AF, in whom sinus rhythm was restored within 48 hours of arrhythmia onset, without anticoagulant treatment. Atrial mechanical function was assessed by transmitral inflow. Soluble thrombomodulin and von Willebrand factor concentrations (both as indices of endothelial damage or dysfunction) and fibrin D-dimer concentrations (as an index of thrombogenesis) were measured. Blood samples were drawn and echocardiographic studies were performed at days 1, 3, 7, and 30 after cardioversion. Research indices were compared with those of 24 healthy participants, 24 patients with chronic AF, and 24 patients with ischaemic heart disease in sinus rhythm.

RESULTS

Patients with AF had higher concentrations of soluble thrombomodulin (acute AF 12.1 (4.1) ng/ml; chronic AF 11.8 (4.6) ng/ml), von Willebrand factor (acute AF 137.2 (36.9) ng/ml; chronic AF 133.1 (25.0) ng/ml), and fibrin D-dimer concentrations (acute AF 2.35 (2.68) microg/ml; chronic AF 1.12 (0.65) microg/ml) than did healthy controls (5.9 (2.7) ng/ml, 86.7 (33.2) ng/ml, and 0.39 (0.28) microg/ml, respectively) and patients with ischaemic heart disease (7.4 (3.7) ng/ml, 110.0 (29.0) ng/ml, and 0.99 (0.73) microg/ml, respectively) (all p < 0.05). Day 30 concentrations of fibrin D-dimer were higher in patients with acute AF than in patients with chronic AF (p = 0.038) but sTM and von Willebrand factor concentrations were not different (both not significant). There were no significant changes in research indices or echocardiographic parameters after cardioversion (all p > 0.05).

CONCLUSIONS

There was evidence among patients with acute onset AF of endothelial damage or dysfunction and increased thrombogenesis, which persisted up to 30 days after cardioversion.

[Horner's syndrome following epidural analgesia for labor]

Horner's syndrome is a disorder of the sympathetic nerve supplying the eye. Infrequently, Horner's syndrome can arise as a complication of epidural anesthesia, but its clinical course is favorable. The incidence increases when epidural analgesia is used in obstetrics because of physiological and anatomic changes in obstetric patients that favor spread of the local anesthetic. We report the case of a 31-year-old woman requiring epidural analgesia for labor. She received 10 mL of 0.15% ropivacaine with a bolus dose of 50 microg of fentanyl, followed by epidural catheter infusion of 0.15% and 0.001% fentanyl at a rate of 10 mL/h. Two hours after starting the infusion, the patient's right eye presented a contracted pupil, a drooping eyelid, and enophthalmos, accompanied by flushing on the same side of the face. Horner's syndrome was diagnosed. Signs resolved over the next hour without treatment. The literature contains reports of widely differing incidences of Horner's Syndrome ranging from 1.3% to 75%. The case we report was the only one in our hospital over a period of 4 years during which 12,796 epidural procedures were performed. These data suggest to us that Horner's syndrome often passes undetected because clinical manifestations are not remarkable. Nevertheless, the diagnosis should be kept in mind so that unnecessary treatment is avoided, given that the clinical course is favorable with spontaneous resolution.