Instrumento para la evaluación del riesgo de arritmias durante el entrenamiento no aeróbico en pacientes con enfermedad cardiovascular / Prediction of arrhythmias during non-aerobic training in patients with cardiovascular disease

Objetivo: El entrenamiento físico de fuerza, flexibilidad, coordinación, propiocepción y equilibrio neuromuscular (fisioterapia) está recomendado en programas de rehabilitación cardiaca. Sin embargo, los pacientes pueden presentar arritmias no pronosticadas en la estratificación del riesgo. El objetivo de este estudio fue realizar un modelo de predicción de arritmias en las sesiones de fisioterapia. Material y método: Estudiamos una cohorte de pacientes (n = 412) que realizaron ejercicios de fisioterapia durante 30 min al día, 3 veces por semana, a intensidad moderada, mientras un cardiólogo supervisaba el trazo electrocardiográfico. Se comparó la presencia de arritmias en sesiones de fisioterapia según su aparición en la prueba de ejercicio (PE) de estratificación. Todo valor de p < 0,05 fue significativo. Finalmente, se realizó un modelo multivariable de regresión logística. Resultados: De los 412 pacientes, 270 (65%) presentaron arritmias en kinesioterapia y no hubo complicaciones mayores. El riesgo relativo para tener arritmias en fisioterapia fue de 1,89 (IC95% 1,25-2,86, p < 0,01), acorde a su presencia en la PE. Otras variables asociadas fueron miocardiopatía dilatada, baja fracción de eyección, uso de digoxina, diuréticos, bajo consumo pico de oxígeno y baja eficiencia ventilatoria (VE/VCO2). En el modelo de regresión, las variables que se mantuvieron significativas fueron: arritmias en la PE, consumo pico de oxígeno y uso de diuréticos. Conclusión: Las arritmias son frecuentes en pacientes con cardiopatía durante las sesiones de fisioterapia y las variables predictivas fueron el uso de diuréticos, el consumo pico de oxígeno y la ocurrencia de arritmias en la PE. Se recomienda supervisar con monitorización electrocardiográfica continua estas sesiones en sujetos de riesgo

Aim: Non-aerobic physical training (NAPhT) sessions with strength, flexibility, coordination, proprioception and neuromuscular balance exercises is recommended in cardiac rehabilitation programs. However, some patients have arrhythmias that are not detected in the risk stratification. The aim of this study was to make a prediction model of arrhythmias during NAPhT sessions. Material and method: We studied a cohort of patients (n= 412) undergoing NAPhT for 30 min, 3 times a week, with a moderate intensity. A cardiologist monitored the electrocardiographic signal. The occurrence of arrhythmia during NAPhT was compared with its presence in the risk stratification stress testing. All P values <.05 were considered significant. Multivariate logistic regression model was also performed. Results: From a total of 412 patients, 270 (65%) showed arrhythmias in NAPhT, without major complications. Relative risk of arrhythmia in NAPhT was 1.89 (95% CI 1.25-2.86, P < .01), when arrhythmia was present during stress testing. In the bivariate analysis, other variables associated were dilated cardiomyopathy, low ejection fraction, use of digoxin, diuretics, low peak oxygen uptake and low ventilatory efficiency. In the regression model, 3 variables remained significant: arrhythmias in stress test, peak oxygen uptake and diuretic. Conclusion: The presence of arrhythmias during NAPhT sessions in patients with heart disease is elevated, and they are associated with diuretic use, peak oxygen uptake values and the presence of arrhythmias in stress testing. Therefore, continuous electrocardiographic monitoring is recommended in these kind of patients

South American Guidelines for Cardiovascular Disease Prevention and Rehabilitation / Diretriz Sul-Americana de Prevenção e Reabilitação Cardiovascular

In this document, the Inter-American Committee of Cardiovascular Prevention and Rehabilitation, together with the South American Society of Cardiology, aimed to formulate strategies, measures, and actions for cardiovascular disease prevention and rehabilitation (CVDPR). In the context of the implementation of a regional and national health policy in Latin American countries, the goal is to promote cardiovascular health and thereby decrease morbidity and mortality. The study group on Cardiopulmonary and Metabolic Rehabilitation from the Department of Exercise, Ergometry, and Cardiovascular Rehabilitation of the Brazilian Society of Cardiology has created a committee of experts to review the Portuguese version of the guideline and adapt it to the national reality. The mission of this document is to help health professionals to adopt effective measures of CVDPR in the routine clinical practice. The publication of this document and its broad implementation will contribute to the goal of the World Health Organization (WHO), which is the reduction of worldwide cardiovascular mortality by 25% until 2025. The study group's priorities are the following: • Emphasize the important role of CVDPR as an instrument of secondary prevention with significant impact on cardiovascular morbidity and mortality; • Join efforts for the knowledge on CVDPR, its dissemination, and adoption in most cardiovascular centers and institutes in South America, prioritizing the adoption of cardiovascular prevention methods that are comprehensive, practical, simple and which have a good cost/benefit ratio; • Improve the education of health professionals and patients with education programs on the importance of CVDPR services, which are directly targeted at the health system, clinical staff, patients, and community leaders, with the aim of decreasing the barriers to CVDPR implementation.

Com este documento, o Comitê Interamericano de Prevenção e Reabilitação Cardiovascular, em posição conjunta com a Sociedade Sul-Americana de Cardiologia, mostra seu interesse no desenvolvimento de estratégias, medidas e intervenções para a prevenção e a reabilitação cardiovascular. Com o objetivo de implementar na América Latina uma política de saúde regional e nacional dos países membros, tem-se o objetivo de promover a saúde cardiovascular e, consequentemente, diminuir a morbimortalidade. O grupo de estudos em Reabilitação Cardiopulmonar e Metabólica do Departamento de Exercício, Ergometria e Reabilitação Cardiovascular de Sociedade Brasileira de Cardiologia (DERC/SBC) criou uma comissão de experts para revisar a versão em português e adaptá-la à realidade nacional. Este documento tem como missão principal auxiliar os profissionais de saúde a alcançarem medidas efetivas de prevenção e reabilitação cardiovascular (RCV) na prática clínica diária. Com a difusão deste documento, bem como com a sua implementação de forma mais abrangente, contribuiremos com a meta da Organização Mundial de Saúde de diminuir a mortalidade cardiovascular no mundo em 25% até o ano de 2025. As prioridades deste grupo de trabalho são: • Enfatizar o caráter prioritário da RCV como instrumento de prevenção secundária com importante impacto na morbimortalidade cardiovascular; • Unir esforços para melhorar o conhecimento da RCV, sua difusão e aplicação na maioria dos centros e institutos cardiovasculares da América do Sul, priorizando a utilização de um método de prevenção cardiovascular integral, prático, de fácil aplicação e de custo/benefício comprovado; • Melhorar a educação do pessoal da saúde e dos pacientes por meio de programas educativos dirigidos, que permitam envolver diretamente os sistemas de saúde, pessoal médico, pacientes e líderes comunitários sobre a importância dos serviços de RCV, a fim de diminuir as barreiras para a sua implantação.

Sleep evaluation scales and questionaries: a review.

INTRODUCTION: Whenever a new scale is created or translated from another language, it must be validated, establishing its reliability for the new population where it will be used. Sleep quality concept is a construct that can be evaluated using self-report scales. Resulting elements vary depending on the individuals surveyed. This type of evaluation is mainly subjective and includes quantitative aspects such as sleep duration, number of awakenings, latency time, and qualitative aspects such as rest sensation, mood and oneiric content (Valencia, 2000). In the present study we made a critical review of the sleep scales designed for child, adolescent and adult populations that have been validated and the difficulties they might present. METHODOLOGY: Between September 2005 and May 2006 a bibliographical search was made within Pubmed, Ovid and the data base of the periodical and book library of the Ramon de la Fuente Muñiz National Institute of Psychiatry, using and combining the following key words: sleep, sleep questionnaire, sleep scale, sleep inventory, adolescent, adolescent sleep scale. The most relevant papers to our study were selected. The search was limited to Spanish and English articles, although there was no year or geographical origin limit. Articles that did not include clinimetrical data where excluded. CONCLUSIONS: Based on our bibliographical search and our discussion, we suggested the design and validation of a Spanish scale to evaluate adolescent population which avoids a time interval between awakening and the answering of the instrument in order to decrease recall bias.

[Malfunction of a permanent pacemaker]. / Disfunción de marcapaso definitivo.

Forty years have gone by since the first pacemaker implant; this fact had strong impact in the life of thousands of persons. The objective of this work is to report the case of definitive pacemaker malfunction with epicardiac lead and review the literature concerning the important aspects of the causes and diagnosis of pacemaker malfunction. We consider that physicians dealing with patients implanted these devices must be prepared to diagnose and treat them adequately.

The Drosophila melanogaster homologue of the Xeroderma pigmentosum D gene product is located in euchromatic regions and has a dynamic response to UV light-induced lesions in polytene chromosomes.

The XPD/ERCC2/Rad3 gene is required for excision repair of UV-damaged DNA and is an important component of nucleotide excision repair. Mutations in the XPD gene generate the cancer-prone syndrome, xeroderma pigmentosum, Cockayne's syndrome, and trichothiodystrophy. XPD has a 5'- to 3'-helicase activity and is a component of the TFIIH transcription factor, which is essential for RNA polymerase II elongation. We present here the characterization of the Drosophila melanogaster XPD gene (DmXPD). DmXPD encodes a product that is highly related to its human homologue. The DmXPD protein is ubiquitous during development. In embryos at the syncytial blastoderm stage, DmXPD is cytoplasmic. At the onset of transcription in somatic cells and during gastrulation in germ cells, DmXPD moves to the nuclei. Distribution analysis in polytene chromosomes shows that DmXPD is highly concentrated in the interbands, especially in the highly transcribed regions known as puffs. UV-light irradiation of third-instar larvae induces an increase in the signal intensity and in the number of sites where the DmXPD protein is located in polytene chromosomes, indicating that the DmXPD protein is recruited intensively in the chromosomes as a response to DNA damage. This is the first time that the response to DNA damage by UV-light irradiation can be visualized directly on the chromosomes using one of the TFIIH components.

Z/AP, a double reporter for cre-mediated recombination.

The Cre/loxP site-specific recombination system combined with embryonic stem cell-mediated technologies has greatly expanded our capability to address normal and disease development in mammals using genetic approaches. The success of this emerging technology hinges on the production of Cre-expressing transgenic lines that provide cell type-, tissue-, or developmental stage-specific recombination between loxP sites placed in the genome. Here we describe and characterize the production of a double-reporter mouse line that provides a convenient and reliable readout of Cre recombinase activity. Throughout all embryonic and adult stages, the transgenic animal expresses the lacZ reporter gene before Cre-mediated excision occurs. Cre excision, however, removes the lacZ gene, allowing expression of the second reporter, the human alkaline phosphatase gene. This double-reporter transgenic line is able to indicate the occurrence of Cre excision in an extremely widespread manner from early embryonic to adult lineages. It will be a valuable reagent for the increasing number of investigators taking advantage of the powerful tools provided by the Cre/loxP site-specific recombinase system.

Kearns-Sayre syndromes an absolute indication for prophylactic implantation of definitive pacemaker?

Kearns-Sayre syndrome is a mitochondrial cytopathy characterized by chronic progressive external ophthalmoplegia, retinitis pigmentosa and heart block, the last of which determines the survival of these patients. The case of a 23 year old man with Kearns-Sayre syndrome, conduction disturbances and mitral valve prolapse is presented. The characteristics of this syndrome are described and the criteria for prophylactic installation of a pacemaker discussed.

Localisation of inositol trisphosphate and ryanodine receptors during mouse spermatogenesis: possible functional implications.

During spermatogenesis the activity of intracellular Ca(2+)-release channels is likely to play an important role in different specific cellular functions. Accordingly, messenger RNAs for the three inositol 1,4,5-trisphosphate receptor (IP3R) subtypes were found to be present throughout spermatogenesis. Immunocytochemical analysis revealed distinct distribution patterns of the mature IP3Rs during sperm differentiation. At early stages, IP3Rs are distributed throughout the cytoplasm, and as differentiation proceeds they become selectively localised to the Golgi complex. Consistently, spermatogonia underwent large intracellular Ca2+ release in response to thapsigargin (TG), while smaller responses were detected in late spermatocytes and spermatids. The distribution of IP3Rs and the larger Ca(2+)-release responses found in spermatogonia, suggest that IP3Rs may be involved in cell proliferation at this stage. This notion is supported by our observations in a spermatogenic cell line that depletion of intracellular Ca2+ pools using TG inhibits cell division, and that incubation with an IP3R-I antisense oligonucleotide completely inhibited proliferation. Furthermore, the three genes encoding ryanodine receptor proteins (RyRs) are expressed at all stages of spermatogenesis. However, immunocytochemical studies with specific antibodies against each of the RyR subtypes detected types 1 and 3 in spermatogenic cells and only type 3 in mature sperm. In contrast to IP3Rs, RyRs remain scattered in the cytoplasm throughout differentiation. Functional responses to caffeine and ryanodine were absent in spermatogenic cells and in mature sperm. These findings suggest that IP3Rs have significantly more important roles in spermatogenesis than RyRs, and that one of these roles is crucial for cell proliferation.

Reactive oxygen species participate in the control of mouse embryonic cell death.

Programmed cell death or apoptosis is an essential process during the morphogenesis of a large number of structures. Evidence obtained over the past few years indicates that, in some cases, the generation of reactive oxygen species (ROS) is an important event during the course of apoptosis. Using an in vitro culture system in which digit individualization of developing limbs normally occurs, we assayed the effect of different antioxidants on the cell death that takes place at interdigits. The addition of phenol, dimethyl sulfoxide, or 2',7'-dichlorodihydrofluorescein diacetate (DCDHF-DA) to murine developing limbs in culture prevented digit individualization as well as the typical interdigital cell death. Two ROS-sensitive dyes, 3-(4,5-dimethylthiazol)-2,5-diphenyl tetrazolium bromide and DCDHF-DA, stained interdigits and the so-called "necrotic zones," implying that they contain cells under oxidative stress. Very few interdigital cells were doubly stained with the ROS probes and two cell death indicators (i.e., acridine orange and propidium iodide), suggesting that they detect a different stage during the course of apoptosis. Furthermore, we found cells stained for ROS that did not express a specific macrophage marker and in a few cases were seen surrounded by a macrophage. Surprisingly, many regions of the midgestation mouse embryo that are undergoing cell death correlated with those that have a markedly higher level of ROS. Our data suggest that the generation of oxidative stress is a common requirement for cell death that occurs during mouse embryonic development.

Control of kinetic properties of AMPA receptor channels by nuclear RNA editing.

AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptor channels mediate the fast component of excitatory postsynaptic currents in the central nervous system. Site-selective nuclear RNA editing controls the calcium permeability of these channels, and RNA editing at a second site is shown here to affect the kinetic aspects of these channels in rat brain. In three of the four AMPA receptor subunits (GluR-B, -C, and -D), intronic elements determine a codon switch (AGA, arginine, to GGA, glycine) in the primary transcripts in a position termed the R/G site, which immediately precedes the alternatively spliced modules "flip" and "flop." The extent of editing at this site progresses with brain development in a manner specific for subunit and splice form, and edited channels possess faster recovery rates from desensitization.

Molecular biology of glutamate receptors.

The ligand-gated receptors for L-glutamate play a central role in acute neuronal degeneration. Recently cDNAs have been isolated for subunits of several glutamate receptor subtypes. By sequence homology all these subunits clearly belong to one large gene family. Several subfamilies exist and match roughly previously pharmacologically and electrophysiologically defined subtypes of glutamate receptors. Currently four genes (GluR A, B, C and D) are known that code for the AMPA subtypes of glutamate receptors. Recombinant expression of wild type and mutated sequences identified a critical residue in the putative TM2 channel-lining segment that controls Ca2+ ion permeability. The arginine (R) found in GluR B subunits at that position renders AMPA channels impermeable for Ca2+ ions, whereas glutamine (Q) containing GluR A, C and D subunits give rise to Ca2+ permeable channels. RNA editing converts the genomically encoded glutamine codon into the arginine codon found in GluR B cDNAs for the Q/R site. NMDA subtypes of glutamate receptors are formed after coexpression of the NR1 cDNA with a cDNA of the NR2 family. Depending on the member of the NR2 family used, NMDA receptors with different kinetical and pharmacological properties are generated. Common to all channels of these NMDA receptors is a high permeability for Ca2+ ions and a voltage dependent block by Mg2+ ions. All currently known NMDA receptor subunits have an asparagine at the Q/R homologous position. We found that this residue is critical for Mg2+ block and Ca2+ permeability of NMDA receptor channels.

The rat delta-1 and delta-2 subunits extend the excitatory amino acid receptor family.

We have characterized a second member (delta-2) of a new class of subunits for the ligand-gated excitatory amino acid receptor superfamily. The sequence of delta-2 exhibits an average identity of 25% and 18.5% to the non-NMDA and NMDA receptor subunits, respectively. The rat delta-2 gene is expressed predominantly in Purkinje cells of the cerebellum whereas only low levels of delta-1 transcripts are found in the adult brain. However, delta-1 gene expression undergoes a pronounced developmental peak, with particularly high mRNA levels in the caudate putamen of late embryonic/early postnatal stages.

High-affinity kainate and domoate receptors in rat brain.

Mammalian brain expresses receptors which bind the potent neurotoxins, kainate and domoate, with high affinity, and which form a subclass of ionotropic glutamate receptors. A new member of these receptors, expressed in both adult and embryonic CNS is compared in its ligand binding properties to its closely sequence-related homologs.

Heteromeric NMDA receptors: molecular and functional distinction of subtypes.

The N-methyl D-aspartate (NMDA) receptor subtype of glutamate-gated ion channels possesses high calcium permeability and unique voltage-dependent sensitivity to magnesium and is modulated by glycine. Molecular cloning identified three complementary DNA species of rat brain, encoding NMDA receptor subunits NMDAR2A (NR2A), NR2B, and NR2C, which are 55 to 70% identical in sequence. These are structurally related, with less than 20% sequence identity, to other excitatory amino acid receptor subunits, including the NMDA receptor subunit NMDAR1 (NR1). Upon expression in cultured cells, the new subunits yielded prominent, typical glutamate- and NMDA-activated currents only when they were in heteromeric configurations with NR1. NR1-NR2A and NR1-NR2C channels differed in gating behavior and magnesium sensitivity. Such heteromeric NMDA receptor subtypes may exist in neurons, since NR1 messenger RNA is synthesized throughout the mature rat brain, while NR2 messenger RNA show a differential distribution.

Quantitative assays based on the use of replicatable hybridization probes.

Amplifiable hybridization probes--molecules with a probe sequence embedded within the sequence of a replicatable RNA--will promote the development of sensitive clinical assays. To demonstrate their utility, we prepared a recombinant RNA that contained a 30-nucleotide-long probe complementary to a conserved region of the pol gene in human immunodeficiency virus type 1 (HIV-1) mRNA. Test samples were prepared, each containing a different number of HIV-1 transcripts that served as simulated HIV-1 mRNA targets. Hybridizations were carried out in a solution containing the chaotropic salt, guanidine thiocyanate. Probe-target hybrids were isolated by reversible target capture on paramagnetic particles. The probes were then released from their targets and amplified by incubation with the RNA-directed RNA polymerase, Q beta replicase (EC 2.7.7.48). The replicase copied the probes in an exponential manner: after each round of copying, the number of RNA molecules doubled. The amount of RNA synthesized in each reaction (approximately 50 ng) was sufficient to measure without using radioisotopes. Kinetic analysis of the reactions demonstrated that the number of HIV-1 targets originally present in each sample could be determined by measuring the time it took to synthesize a particular amount of RNA (the longer the synthesis took, the fewer the number of targets originally present). The results suggest that clinical assays involving replicatable hybridization probes will be simple, accurate, sensitive, and automatable.

Plasmid vector pBR322 and its special-purpose derivatives--a review.

The plasmid pBR322 was one of the first EK2 multipurpose cloning vectors to be designed and constructed (ten years ago) for the efficient cloning and selection of recombinant DNA molecules in Escherichia coli. This 4363-bp DNA molecule has been extensively used as a cloning vehicle because of its simplicity and the availability of its nucleotide sequence. The widespread use of pBR322 has prompted numerous studies into its molecular structure and function. These studies revealed two features that detract from the plasmid's effectiveness as a cloning vector: plasmid instability in the absence of selection and, the lack of a direct selection scheme for recombinant DNA molecules. Several vectors based on pBR322 have been constructed to overcome these limitations and to extend the vector's versatility to accommodate special cloning purposes. The objective of this review is to provide a survey of these derivative vectors and to summarize information currently available on pBR322.