Ultra-early continuous cardiac monitoring improves atrial fibrillation detection and prognosis of patients with cryptogenic stroke.

BACKGROUND AND PURPOSE: Subclinical atrial fibrillation (AF) is known to underlie a number of cases of cryptogenic stroke (CrS). However, there is need to define the most effective strategy for AF detection. The diagnostic usefulness was analysed of a strategy based on ultra-early continuous monitoring in patients with CrS in terms of AF detection, oral anticoagulation treatment and stroke recurrence, in comparison to a standard outpatient strategy. METHODS: Patients with ischaemic stroke of undetermined origin and confirmed to be cryptogenic after extensive work-up were searched for AF with (i) a conventional strategy (historical cohort, n = 101) with serial electrocardiograms and 24-h Holter monitoring or (ii) an ultra-early monitoring strategy with insertable cardiac monitor (ICM) implanted before discharge (prospective cohort, n = 90). AF episodes lasting >1 min, anticoagulant treatment and stroke recurrence were recorded. RESULTS: During admission, AF was similarly detected in both cohorts (24% of patients). After discharge (mean follow-up 30 ± 10 months), AF detection rates were 17/80 (21.3%) and 38/65 (58.5%) for patients in the conventional versus the ultra-early ICM group (P < 0.001). Up to 41% of AF cases in the ICM cohort were detected within the first month. Oral anticoagulation was initiated in 37.6% versus 65.5% (P < 0.001) and stroke recurrence was recorded in 10.9% versus 3.3% (P 0.04) in the conventional versus the ICM cohort. CONCLUSIONS: Pre-discharge ICM implant allows detection of AF during follow-up in up to 58% of selected patients with CrS. Compared to a conventional strategy, ultra-early ICM implant results in higher anticoagulation rates and a decrease in stroke recurrence.

No transmission of SARS-CoV-2 in a patient undergoing allogeneic hematopoietic cell transplantation from a matched-related donor with unknown COVID-19.

The Hematology Department and its Hematopoietic Cell Transplantation (HCT) program implemented several measures during COVID-19 outbreak in order to keep clinical activities with the maximum security for both donors and recipients. Nevertheless, there was a lack of evidence whether blood products and specifically bone marrow can cause transfusion-transmitted infection. Initially, there were many uncertainties and did not exist formal recommendations. Before official statements were available, we performed an allogeneic HCT in a 57-year-old male from a related matched donor in the incubation period of COVID-19 where the patient did not develop the disease. Actual epidemiology data suggest that transmission may occur early in the course of infection, even from asymptomatic patients in the incubation period. In our knowledge this is the first case report of an adult hematopoietic cell donor with COVID-19 in the incubation period where the transplant is successfully completed with no transmission of SARS-CoV-2. The low concentration of viral RNA in plasma of patients with COVID-19 could support the safety of blood products, including peripheral blood hematopoietic cells. In conclusion, blood products including hematopoietic stem cells are safe in the context of COVID-19 pandemic.

Neurohormonal activation induces intracellular iron deficiency and mitochondrial dysfunction in cardiac cells.

BACKGROUND: Iron deficiency (ID) is common in patients with heart failure (HF) and is associated with poor outcomes, yet its role in the pathophysiology of HF is not well-defined. We sought to determine the consequences of HF neurohormonal activation in iron homeostasis and mitochondrial function in cardiac cells. METHODS: HF was induced in C57BL/6 mice by using isoproterenol osmotic pumps and embryonic rat heart-derived H9c2 cells were subsequently challenged with Angiotensin II and/or Norepinephrine. The expression of several genes and proteins related to intracellular iron metabolism were assessed by Real time-PCR and immunoblotting, respectively. The intracellular iron levels were also determined. Mitochondrial function was analyzed by studying the mitochondrial membrane potential, the accumulation of radical oxygen species (ROS) and the adenosine triphosphate (ATP) production. RESULTS: Hearts from isoproterenol-stimulated mice showed a decreased in both mRNA and protein levels of iron regulatory proteins, transferrin receptor 1, ferroportin 1 and hepcidin compared to control mice. Furthermore, mitoferrin 2 and mitochondrial ferritin were also downregulated in the hearts from HF mice. Similar data regarding these key iron regulatory molecules were found in the H9c2 cells challenged with neurohormonal stimuli. Accordingly, a depletion of intracellular iron levels was found in the stimulated cells compared to non-stimulated cells, as well as in the hearts from the isoproterenol-induced HF mice. Finally, neurohormonal activation impaired mitochondrial function as indicated by the accumulation of ROS, the impaired mitochondrial membrane potential and the decrease in the ATP levels in the cardiac cells. CONCLUSIONS: HF characteristic neurohormonal activation induced changes in the regulation of key molecules involved in iron homeostasis, reduced intracellular iron levels and impaired mitochondrial function. The current results suggest that iron could be involved in the pathophysiology of HF.

Role of genetic testing in arrhythmogenic right ventricular cardiomyopathy/dysplasia.

In a cohort of patients with confirmed or suspected arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D), genetic testing is useful in confirming the diagnosis, particularly in individuals who do not completely fulfil Task Force criteria for the disease, thereby also enabling the adoption of preventive measures in family members. Due to the high percentage of novel mutations that are expected to be identified in ARVC/D, the use of genetic screening technology based on the identification of known mutations seems to have very restricted value. Our results support that the presence of certain genetic variations could play a role in the final phenotype of patients with ARVC/D, where single and compound mutation carriers would have more symptomatic forms of the disease and the polymorphism P366L could be associated to a more benign phenotype.

Temporal evolution of a seismic sequence induced by a gas injection in the Eastern coast of Spain.

Induced seismicity associated with energy production is becoming an increasingly important issue worldwide for the hazard it poses to the exposed population and structures. We analyze one of the rare cases of induced seismicity associated with the underwater gas storage operations observed in the Castor platform, located in the Valencia gulf, east Spain, near a complex and important geological structure. In September 2013, some gas injection operations started at Castor, producing a series of seismic events around the reservoir area. The larger magnitude events (up to 4.2) took place some days after the end of the injection, with EMS intensities in coastal towns up to degree III. In this work, the seismic sequence is analyzed with the aim of detecting changes in statistical parameters describing the earthquake occurrence before and after the injection and identifying possible proxies to be used for monitoring the sequence evolution. Moreover, we explore the potential predictability of these statistical parameters which can be used to control the field operations in injection/storage fluid reservoirs. We firstly perform a retrospective approach and next a perspective analysis. We use different techniques for estimating the value of the expected maximum magnitude that can occur due to antropogenic activities in Castor.

Elevated levels of serum interleukin-6 are associated with low grade cellular rejection in patients with heart transplantation.

UNLABELLED: Endomyocardial biopsy is the gold-standard procedure to diagnose acute cellular rejection after heart transplantation. This study assessed whether the blood levels of cytokines involved in inflammation and immune activation are useful to detect the presence of acute cellular rejection. METHODS: Blood specimens collected before 275 endomyocardial biopsies in 66 patients were assayed for levels of TNFalpha, IL6, IL1beta, and IL2 receptor. The biopsies were grouped according to the presence (n = 41) or absence (n = 234) of acute cellular rejection grade > or = 3A of the International Society for Heart and Lung Transplantation. We compared the levels of cytokines in the two groups. RESULTS: Circulating IL6 levels were significantly higher when there was a low grade (0-2) cellular rejection in the biopsy versus the group of biopsies grade > or = 3A (19.8 +/- 27 versus 12.9 +/- 10 pg/mL; P = .001). An IL6 level higher than 30 pg/mL showed a negative predictive value of 95% for the presence of acute rejection grade > or = 3A. CONCLUSION: In heart transplant patients, high levels of serum IL6 were associated with low grade cellular rejection. Determination of IL6 levels may be useful to reduce the number of endomyocardial biopsies during follow-up in these patients.

Úlcera duodenal benigna con penetración en cabeza de páncreas, con obstrucción de la vía biliar / Benign duodenal ulcer penetrating into pancreas, with obstruction of common bile duct

Resumen Objetivo: Reportamos un caso clínico con presentación atípica de una úlcera duodenal benigna que simula el cuadro clínico y radiológico de una neoplasia de páncreas. Materiales y Método: Presentamos el caso de un varón de 83 años que debuta con un cuadro clínico de astenia e ictericia mucocutánea. En estudio de imagen se identifica una masa en cabeza pancreática. En estudio endoscópico se observa úlcera duodenal benigna penetrada a cabeza de páncreas que condiciona obstrucción de vía biliar. Discusión y Conclusiones: El manejo de estos pacientes suele ser quirúrgico porque desarrollan un deterioro asociado a sepsis o perforación. Si la situación clínica lo permite se puede intentar un tratamiento conservador. En nuestro caso el paciente precisó un mes de hospitalización con antibioticoterapia intravenosa de amplio espectro, reposo alimentario, nutrición parenteral y tratamiento con inhibidores de la bomba de protones (IBP) para la resolución del cuadro. La penetración o fistulización a la cabeza del páncreas es una complicación grave e infrecuente de la enfermedad ulcerosa péptica. Su manejo puede ser conservador en casos seleccionados donde no exista perforación de la úlcera a la cavidad peritoneal, ni exista deterioro séptico ni hemodinámico.

Aim: To report an atypical presentation of a benign duodenal ulcer that simulates pancreatic neoplasia. Materials and Method: A case of a 83 years old male patient with astenia and jaundice due to a benign duodenal ulcer penetrating into the pancreas with obstruction of common bile duct. Imagining study identified a pancreatic head mass. The patient required one month admission, receiving broad-spectrum antibiotics, parenteral nutrition and intravenous proton pump inhibitors. Discussion and Conclusion: Due to frequent complications associated to this condition, such as haemodynamic failure, sepsis or free peritoneal perforation, surgery is the main treatment. However, in mild cases, as in our patient, conservative management can be considered. Penetration or fistulization to the head of the pancreas is a rare and serious complication of peptic ulcer disease. Its management can be conservative in selected cases where there is no perforation of the ulcer into the peritoneal cavity, nor septic or hemodynamic deterioration.

Half-life of the plasma membrane ATPase and its activating system in resting yeast cells.

The stability of the yeast plasma membrane ATPase and its activating system has been investigated in resting Saccharomyces cerevisiae. The half-life of ATPase in the presence of glucose is about 11 h whereas in the presence of ethanol it is greater than 30 h. In the case of the ATPase activating system half-life values of about 5 and 14 h have been observed, respectively, in the presence of these substrates. These results indicate that, similarly to sugar transport systems, plasma membrane ATPase as well as its activating system are less stable than the bulk of proteins in this organism. The fact that all plasma membrane proteins so far examined show low half-life values suggests that a low stability could be a general characteristic of these proteins.

Overexpression of the sodium ATPase of Saccharomyces cerevisiae: conditions for phosphorylation from ATP and Pi.

The ENA1 gene of Saccharomyces cerevisiae encodes a putative ATPase necessary for Na+ efflux. Plasma membranes and intracellular membranes of a yeast strain overexpressing the ENA1 gene contain significant amounts of ENA1 protein. Consequences of the overexpression with reference to the wild-type strain are: (1) a 5-fold higher content of the ENA1-protein in plasma membranes; (2) lower Na+ and Li+ effluxes; (3) slightly higher Na+ tolerance; and (4) much higher Li+ tolerance. The ENA1-specific ATPase activity in plasma membrane preparations of the overexpressing strain was low, but an ENA1 phosphoprotein was clearly detected when the plasma membranes were exposed to ATP in the presence of Na+ or to Pi in the absence of Na+. The characteristics of this phosphoprotein, which correspond to the acyl phosphate intermediaries of P-type ATPases, the absolute requirement of Na+ or other alkali cations for phosphorylation, and the Na+ and pH dependence of phosphorylation from ATP and Pi suggest that the product of the ENA1 gene may be a Na,H-ATPase, which can also pump other alkali cations. The role of the intracellular membranes structures produced with the overexpression of ENA1 in Na+ and Li+ tolerances and the existence of a beta-subunit of the ENA1 ATPase are discussed.

Insulin regulation of malic enzyme gene expression in rat liver: evidence for nuclear proteins that bind to two putative insulin response elements.

Diabetes in rats is characterized by insulin deficiency accompanied by a decrease in lipogenic enzymes. The malic enzyme (ME) gene, which encodes an important lipogenic enzyme, was used to investigate insulin regulation of gene expression. ME mRNA levels were reduced by more than 90% in the liver of diabetic rats. The administration of insulin (3 U/15 days) to either control or diabetic rats increased ME mRNA by 2- to 10-fold, respectively. Since diabetes reduces circulating T3 and the levels of nuclear T3-receptors, the potential role of thyroid hormone on insulin regulation of ME gene expression was also evaluated in thyroidectomized-diabetic rats. In these animals the levels of ME mRNA were undetectable but were increased by insulin even in the absence of thyroid hormones. These in vivo effects of insulin and T3 were not additive. The transcription rate of the gene was also reduced in the diabetic liver and recovered after insulin therapy. By computer analyses we have identified two different putative insulin response elements (IREs) in the ME gene promoter, hereafter referred to as IRE-I (-683 to -692), which is similar to the phosphoenol pyruvate carboxy kinase promoter IRE and IRE-II (-161 to -170), which is similar to the glyceraldehyde phosphate dehydrogenase gene promoter IRE-A. Results from gel retardation assays suggest that a single nuclear protein binds to IRE-I whereas two different nuclear proteins bind to IRE-II. The protein/IRE-I complex increased in liver nuclear extracts from diabetic rats and decreased after insulin administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Turnover of the K+ transport system in Saccharomyces cerevisiae.

The stability of the K+ transport system in Saccharomyces cerevisiae has been studied upon inhibition of protein synthesis with cycloheximide. Addition of the antibiotic gave rise to an inactivation of this transport. This activation followed first-order kinetics and was stimulated by the presence of a fermentable substrate. A half-life of about 4 h could be calculated in the presence of glucose. The results indicate that, similarly to sugar carriers, K+ transport system is less stable than the bulk of proteins of this organism.

In vivo activation of the yeast plasma membrane ATPase during nitrogen starvation. Identification of the regulatory domain that controls activation.

Yeast plasma membrane ATPase is activated during nitrogen starvation when a fermentable substrate is present. This activation is due to changes in the Vmax and it is irreversible, independent of protein synthesis and apparently triggered by a decrease in the intracellular pH. It is shown that the ATPase regulatory domain implicated in the activation by fermentable carbon sources is also implicated in activation by nitrogen starvation and by external acidification.

Norepinephrine, tri-iodothyronine and insulin upregulate glyceraldehyde-3-phosphate dehydrogenase mRNA during Brown adipocyte differentiation.

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene expression was studied in differentiating brown adipocytes. Northern blot analysis showed that GAPDH mRNA levels increased during differentiation of precursor cells into mature adipocytes, mainly in the initial stages of the differentiation process. Insulin, tri-iodothyronine (T(3)) and norepinephrine, the main regulators of brown adipose tissue function, upregulated GAPDH mRNA levels, whereas retinoic acid inhibited them. The effect of insulin was present on all culture days examined, was time- and dose-dependent, and was exerted through its own receptors, as demonstrated by comparing insulin and insulin-like growth factor (IGF)-I and -II potencies in this system. Using the transcriptional inhibitor, actinomycin D, we demonstrated that T(3), and to a lesser extent insulin, stabilized GAPDH mRNA. Experiments with cycloheximide indicated that both hormones require de novo protein synthesis to achieve their effects. Using cAMP analogs, we showed that the effect of norepinephrine is probably exerted through this second messenger. Co-operation was elucidated between norepinephrine- and insulin-mediated induction of GAPDH mRNA levels. In summary, we have demonstrated that GAPDH mRNA is subjected to multifactorial regulation in differentiating brown adipocytes that includes differentiation of precursor cells and the lipogenic/lipolytic regulators of the tissue.

La concentración plasmática de microARN-1-3p se asocia con fibrilación auricular subclínica en los pacientes con ictus criptogénico / Plasma levels of miRNA-1-3p are associated with subclinical atrial fibrillation in patients with cryptogenic stroke

Introducción y objetivos La identificación de biomarcadores de fibrilación auricular (FA) subclínica en los pacientes con ictus criptogénico (ICr) es de gran interés. Con dicho objetivo, se evaluó el perfil de microARN circulante de los pacientes con ICr y FA frente a aquellos en ritmo sinusal. Métodos Se incluyó a 64 pacientes con ICr consecutivos monitorizados mediante Holter subcutáneo. Se seleccionó a 18 pacientes (9 con FA y 9 en ritmo sinusal persistente) para determinación de 754 microARN mediante tecnología de alto rendimiento. Se incluyó a 9 pacientes adicionales con ictus y FA concomitante para guiar la selección de microARN. Los microARN de interés se replicaron en una cohorte independiente (n=46). La asociación de biomarcadores con FA a los 6 y 12 meses se analizó mediante regresión logística. Resultados Ocho microARN mostraron expresión diferencial entre los pacientes con y sin FA. El miR-1-3p, un regulador génico involucrado en la arritmogénesis cardiaca, fue el único que permaneció significativamente más elevado en pacientes con ICr y FA de la cohorte de repetición, y además mostró una discreta asociación con la carga arrítmica. Los valores de miR-1-3p por encima de la mediana y la fracción de eyección de la aurícula izquierda se asociaron de forma independiente con la presencia de FA a los 6 y 12 meses. Conclusiones En nuestra cohorte, los valores plasmáticos de miR-1-3p fueron más altos en los pacientes con ICr y FA en el seguimiento. Nuestros resultados indican que el miR-1-3p podría ser un nuevo biomarcador de FA oculta en los pacientes con ICr (AU)

Introduction and objectives Identifying biomarkers of subclinical atrial fibrillation (AF) is of most interest in patients with cryptogenic stroke (CrS). We sought to evaluate the circulating microRNA (miRNA) profile of patients with CrS and AF compared with those in persistent sinus rhythm. Methods Among 64 consecutive patients with CrS under continuous monitoring by a predischarge insertable monitor, 18 patients (9 with AF and 9 in persistent sinus rhythm) were selected for high-throughput determination of 754 miRNAs. Nine patients with concomitant stroke and AF were also screened to improve the yield of miRNA selection. Differentially expressed miRNAs were replicated in an independent cohort (n=46). Biological markers were stratified by the median and included in logistic regression analyses to evaluate their association with AF at 6 and 12 months. Results Eight miRNAs were differentially expressed between patients with and without AF. In the replication cohort, miR-1-3p, a gene regulator involved in cardiac arrhythmogenesis, was the only miRNA to remain significantly higher in patients with CrS and AF vs those in sinus rhythm and showed a modest association with AF burden. High (= above the median) miR-1-3p plasma values, together with a low left atrial ejection fraction, were independently associated with the presence of AF at 6 and 12 months. Conclusions In this cohort, plasma levels of miR-1-3p were elevated in CrS patients with subsequent AF. Our results preliminarily suggest that miR-1-3p could be a novel biomarker that, together with clinical parameters, could help identify patients with CrS and a high risk of occult AF (AU)

Combination of clinical risk profile, early exercise testing and circulating biomarkers for evaluation of patients with acute chest pain without ST-segment deviation or troponin elevation.

OBJECTIVE: To investigate the combination of clinical data, exercise testing and biomarkers for the evaluation of patients with chest pain without ST-segment deviation or troponin elevation. DESIGN: Prospective cohort design. SETTTING: Two teaching hospitals in Spain. PATIENTS: 422 patients presenting to the emergency department were studied. Leukocyte count, C-reactive protein (CRP), pregnancy-associated plasma protein A (PAPP-A) and N-terminal pro-brain natriuretic peptide (NT-proBNP) were determined. A validated clinical risk score (number of points according to pain characteristics and risk factors) was used for clinical evaluation and early exercise testing was performed. MAIN OUTCOME MEASURES: Adverse events (death, myocardial infarction or revascularisation) during a median 60 weeks follow-up. RESULTS: By receiver operating characteristic curve analysis, the association between death or myocardial infarction and adverse events was not significant with leukocyte count (p = 0.3, p = 0.3) or CRP (p = 0.5, p = 0.8), was borderline significant with PAPP-A (p = 0.07, p = 0.04) and strongly significant with NT-pro-BNP (p = 0.0001, p = 0.0001). By Cox regression including clinical risk score, exercise testing result and biomarkers, exercise testing was the independent predictor of revascularisation (p = 0.0001), whereas risk score (p = 0.03) and NT-proBNP (p = 0.0004) predicted death or myocardial infarction. The inclusion of NT-proBNP improved the accuracy of the model for death or myocardial infarction (C-statistic 0.84 versus 0.76, p = 0.01). The combination of clinical score and NT-proBNP afforded the stratification in high (17.2%, p = 0.0001), intermediate (5.3%) and low (1.1%) risk categories of death or myocardial infarction. CONCLUSIONS: NT-proBNP provides incremental prognostic information above that given by clinical history and exercise testing in patients with chest pain without ST-segment deviation and negative troponin.

The low-affinity component of Saccharomyces cerevisiae maltose transport is an artifact.

It has been reported by several laboratories that maltose transport in Saccharomyces cerevisiae consists of two components with high- and low-affinity constants for maltose. We have investigated the characteristics of the low-affinity component and have found that it shows an abnormal behavior without similarity to any transport mechanism described in this organism. The results strongly indicate that this apparent transport activity is due not to a genuine transport process but to nonspecific binding of maltose to the cell wall and plasma membrane.

Inhibition of biosynthesis of Saccharomyces cerevisiae sugar transport system by tunicamycin.

Tunicamycin apparently inhibited the biosynthesis of glucose, galactose, and maltose transport systems in Saccharomyces cerevisiae. Under the conditions used, the antibiotic also blocked the biosynthesis of invertase, a well-known yeast glycoprotein, as well as the glycosylation of a marker mannoprotein of the yeast cell wall. However, the antibiotic did not affect certain proteins which did not contain carbohydrate. It seems, therefore, that these sugar carriers are glycoproteins.

Molecular cloning of the calcium and sodium ATPases in Neurospora crassa.

Using PCR, reverse transcription-PCR (RT-PCR) and colony hybridization in a genomic library, we isolated six genes which encode type II P-type ATPases in Neurospora crassa. The six full-length cDNAs were cloned in a yeast expression vector and transformed into Saccharomyces cerevisiae null Ca2+- or Na+-ATPase mutants. Three cDNAs suppressed the defect of the Ca2+ mutant and two of these protected from Mn2+ toxicity. One cDNA suppressed the defect of the Na+ mutant and two cDNAs were not functional in S. cerevisiae. The expression of the transcripts of the six genes in the presence of Ca2+, Na+, high pH or supporting an osmotic shock indicated that, with the exception of one of the Ca2+-ATPases, the main function of the cloned ATPases is the adaptation to stress conditions. The relationship between the cloned fungal Ca2+- and Na+-ATPases and plant type II P-ATPases is discussed.