Different acquisition systems for heart rate variability analysis may lead to diverse outcomes.

Heart rate variability (HRV) is a relevant physiological variable for the estimation of cardiac autonomic function. Although the gold standard for HRV registration is the electrocardiogram (ECG), several applications (APPs) have been increasingly developed. The evaluation carried out by these devices must be compatible with ECG standards. The aim of this study was to compare the data obtained simultaneously with ECG and APP with chest heart rate transmitters. Fifty-six healthy individuals (28 men and 28 women) were evaluated at rest through a short simultaneous HRV measurement with both devices. Data from both acquisition systems were analyzed separately using their own analysis software and exported and analyzed using a validated software. Signal recordings were compatible between the two acquisition systems (Pearson r=0.99; P<0.0001). Although a high correlation was found for the HRV variables obtained in the time domain (Spearman r=0.99; P<0.0001), the correlation decreased in the frequency domain (Pearson r=0.85; P<0.0001) when two software programs were used. Comparison of the averages of spectral analysis parameters also showed differences when HRV data were analyzed separately in each device for low-frequency (LF) and high-frequency (HF) bands. Although the portability of these mobile devices allows for optimal HRV evaluation, the direct analysis obtained from these devices must be carefully evaluated with respect to frequency domain parameters.

Different acquisition systems for heart rate variability analysis may lead to diverse outcomes

Heart rate variability (HRV) is a relevant physiological variable for the estimation of cardiac autonomic function. Although the gold standard for HRV registration is the electrocardiogram (ECG), several applications (APPs) have been increasingly developed. The evaluation carried out by these devices must be compatible with ECG standards. The aim of this study was to compare the data obtained simultaneously with ECG and APP with chest heart rate transmitters. Fifty-six healthy individuals (28 men and 28 women) were evaluated at rest through a short simultaneous HRV measurement with both devices. Data from both acquisition systems were analyzed separately using their own analysis software and exported and analyzed using a validated software. Signal recordings were compatible between the two acquisition systems (Pearson r=0.99; P<0.0001). Although a high correlation was found for the HRV variables obtained in the time domain (Spearman r=0.99; P<0.0001), the correlation decreased in the frequency domain (Pearson r=0.85; P<0.0001) when two software programs were used. Comparison of the averages of spectral analysis parameters also showed differences when HRV data were analyzed separately in each device for low-frequency (LF) and high-frequency (HF) bands. Although the portability of these mobile devices allows for optimal HRV evaluation, the direct analysis obtained from these devices must be carefully evaluated with respect to frequency domain parameters.

Insights on the epigenetic mechanisms underlying pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH), characterized by localized increased arterial blood pressure in the lungs, is a slow developing long-term disease that can be fatal. PAH is characterized by inflammation, vascular tone imbalance, pathological pulmonary vascular remodeling, and right-sided heart failure. Current treatments for PAH are palliative and development of new therapies is necessary. Recent and relevant studies have demonstrated that epigenetic processes may exert key influences on the pathogenesis of PAH and may be promising therapeutic targets in the prevention and/or cure of this condition. The aim of the present mini-review is to summarize the occurrence of epigenetic-based mechanisms in the context of PAH physiopathology, focusing on the roles of DNA methylation, histone post-translational modifications and non-coding RNAs. We also discuss the potential of epigenetic-based therapies for PAH.

Insights on the epigenetic mechanisms underlying pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH), characterized by localized increased arterial blood pressure in the lungs, is a slow developing long-term disease that can be fatal. PAH is characterized by inflammation, vascular tone imbalance, pathological pulmonary vascular remodeling, and right-sided heart failure. Current treatments for PAH are palliative and development of new therapies is necessary. Recent and relevant studies have demonstrated that epigenetic processes may exert key influences on the pathogenesis of PAH and may be promising therapeutic targets in the prevention and/or cure of this condition. The aim of the present mini-review is to summarize the occurrence of epigenetic-based mechanisms in the context of PAH physiopathology, focusing on the roles of DNA methylation, histone post-translational modifications and non-coding RNAs. We also discuss the potential of epigenetic-based therapies for PAH.

Integrity of the dorsolateral periaqueductal grey is essential for the fight-or-flight response, but not the respiratory component of a defense reaction.

Periaqueductal grey is believed to be one of the key structures of the central respiratory stress network. Previous studies established that stimulation of the periaqueductal grey, especially its dorsolateral division (dlPAG), evokes tachypnea as well as increases in other autonomic parameters and motor activity. We investigated the effects of blockade of the dlPAG with GABAA agonist muscimol on respiration during stress and presentation of brief alerting stimuli in conscious unrestrained rats. We found that integrity of the dlPAG is not essential for stress-induced increase in basal/resting respiratory rate or for generation of respiratory responses to brief alerting stimuli. However, blockade of the dlPAG reduced the amount of motor activity and concomitant high-frequency respiratory activity during restraint and the first 5min of novelty stress. We conclude that the integrity of the dlPAG is not essential for generation of respiratory component of the defense reaction, but it mediates expression of the fight-or-flight response including its respiratory component.

Scavenging of NADPH oxidase-derived superoxide anions improves depressed baroreflex sensitivity in spontaneously hypertensive rats.

In pathological conditions, such as hypertension, there is impairment in the autonomic control of blood pressure resulting in changes in baroreflex sensitivity. In the present study we tested the hypothesis that acute superoxide scavenging would restore the depressed baroreflex sensitivity (BRS) in spontaneously hypertensive rats (SHR). Male 10-week-old SHR (n = 14) and their controls (Wistar-Kyoto (WKY) rats; n = 14) underwent femoral artery and vein catheterization for conscious blood pressure recording and drug administration. The BRS was obtained by the drug-induced method using phenylephrine (8 µg/kg, i.v.) and sodium nitroprusside (25 µg/kg, i.v.) before and after the administration of tiron (30 mg/kg, i.v.), a superoxide dismutase mimetic, or apocynin (30 µg/kg), an NADPH oxidase inhibitor. Spontaneously hypertensive rats was significantly hypertensive compared with WKY rats (160 ± 7 vs 105 ± 2 mmHg, respectively). However, there was no significant difference in heart rate between the two groups (388 ± 10 vs 370 ± 20 b.p.m.). In addition, SHR exhibited a diminished BRS compared with WKY rats (-1.34 ± 0.11 vs -2.91 ± 0.20 b.p.m./mmHg, respectively). Administration of tiron improved BRS in SHR (from -1.34 ± 0.11 to 2.26 ± 0.21 b.p.m./mmHg), as did apocynin (to -2.14 ± 0.23 b.p.m./mmHg). Serum samples from SHR (n = 20) and WKY rats (n = 20) were collected for thiobarbituric acid-reactive substances assays before and after tiron or apocynin to confirm the reduction in oxidative stress. There was considerably greater oxidative stress in SHR compared with WKY rats (36.2 ± 3.0 vs 13.3 ± 2.6 nmol/L, respectively). Both apocynin and tiron treatment reduced the oxidative stress in SHR (from 36.2 ± 3.0 to 21.5 ± 3.0 nmol/L and from 37.2 ± 3.9 to 21.9 ± 1.6 nmol/L, respectively). The data suggest that acute scavenging of NADPH oxidase-derived superoxide improves baroreflex sensitivity in SHR.

Angiotensin-II-induced reactive oxygen species along the SFO-PVN-RVLM pathway: implications in neurogenic hypertension

Neurogenic hypertension has been the subject of extensive research worldwide. This review is based on the premise that some forms of neurogenic hypertension are caused in part by the formation of angiotensin-II (Ang-II)-induced reactive oxygen species along the subfornical organ-paraventricular nucleus of the hypothalamus-rostral ventrolateral medulla pathway (SFO-PVN-RVLM pathway). We will discuss the recent contribution of our laboratory and others regarding the mechanisms by which neurons in the SFO (an important circumventricular organ) are activated by Ang-II, how the SFO communicates with two other important areas involved in sympathetic activity regulation (PVN and RVLM) and how Ang-II-induced reactive oxygen species participate along the SFO-PVN-RVLM pathway in the pathogenesis of neurogenic hypertension.

Angiotensin-II-induced reactive oxygen species along the SFO-PVN-RVLM pathway: implications in neurogenic hypertension.

Neurogenic hypertension has been the subject of extensive research worldwide. This review is based on the premise that some forms of neurogenic hypertension are caused in part by the formation of angiotensin-II (Ang-II)-induced reactive oxygen species along the subfornical organ-paraventricular nucleus of the hypothalamus-rostral ventrolateral medulla pathway (SFO-PVN-RVLM pathway). We will discuss the recent contribution of our laboratory and others regarding the mechanisms by which neurons in the SFO (an important circumventricular organ) are activated by Ang-II, how the SFO communicates with two other important areas involved in sympathetic activity regulation (PVN and RVLM) and how Ang-II-induced reactive oxygen species participate along the SFO-PVN-RVLM pathway in the pathogenesis of neurogenic hypertension.

Characterization of reproductive disorders in ewes given an intrauterine dose of Toxoplasma gondii tachyzoites during the intrauterine insemination.

The aim of this study was to characterize the reproductive disorders in the acute and chronic phases in ewes experimentally infected with different doses of Toxoplasma gondii during artificial insemination occurred. Animals (n=41) were divided into three experimental groups: in the group 1 (G1, n=15), animals were inseminated using contaminated semen containing 6.5×104 tachyzoites; in the group 2 (G2, n=15), animals were inseminated with contaminated semen containing 4×107 tachyzoites and in the group 3 (G3, n=11), animals were inseminated using tachyzoite-free semen, serving as control group. Parasitemia and seroconversion were observed in 28 of 30 and 20 of 30, respectively, from the seventh day after infection. Embryonic reabsorption was observed in the acute phase in ewes from G1 and G2. Persistent anestrus, hydrometra, mucometra and follicular cysts were observed in the second phase of the experiment in animals from G1 and G2. Histopathological lesions similar to those of toxoplasmosis were found in the placentas. In conclusion, artificial insemination using semen containing experimentally added tachyzoites can establish toxoplasmosis in ewes and cause reproductive pathologies during the acute and chronic phases of the disease.

[Central neuropathic pain and its relation to the quality of life of a person with a traumatic spinal cord injury]. / Dolor neuropático central y su relación con la calidad de vida de una persona portadora de una lesión medular traumática.

INTRODUCTION AND AIMS: To conduct an exploratory cross-sectional study carried out in the city of Fortaleza (Ceara, Brazil) with the aim of evaluating the relation between central neuropathic pain and the quality of life in individuals with central neuropathic pain due to traumatic injury. PATIENTS AND METHODS: The study examined the cases of 17 adult paraplegic patients with complete traumatic injuries, mainly due to perforations caused by gunshot wounds. The sample was divided into two groups: 1) those with pain, and 2) those with intense pain (more than 20 points according to McGill and eight on the numerical visual scale). The instruments used were the following: the MOS 36-item Short-Form Health Survey (SF-36) and the McGill pain questionnaire, oriented towards the descriptors and the numerical visual scale. RESULTS: The quality of life of patients with central neuropathic pain due to a spinal cord injury is greatly compromised and when the pain is intense the quality of life is even more effected, especially in the following areas: "functional capacity" (p = 0.005), "general state of health" (p = 0.003), "mental health" (p = 0.035), "social aspects" (p = 0.006) and "pain" (p = 0.003). CONCLUSIONS: The quality of life in patients with neuropathic pain due to a traumatic spinal cord injury is severely compromised and the more intense this pain is, the greater its effect on the quality of life will be. It can also be stated that the instruments used were valid for this type of patients (in spite of certain shortcomings) given the complexity and subjectivity of the matter.

[Teaching psychiatric nursing in Ceara: a reality in outline]. / O ensino de enfermagem psiquiátrica no Ceará: a realidade que se esboça.

The teaching of Psychiatric Nursing Course in the Nursing Undergraduate Programs in Ceará, topic of this study, is a reality that has been building up, fusing itself, in a broader context, the teaching of Nursing as a whole. To study it, attempts have been made in order to go deep in the Institutions' formal discourse, (Syllabuses, Course Programs) and in the ideological discourse of social actors which are responsible for the passing on the knowledge absorbed there, produced and reproduced. In the analysis under a structural-historical approach it has been possible to notice that the Psychiatric Nursing Courses are going through a moment of reflection, uncertainties and changes which have been originated by the process of syllabus reform and of the psychiatric assistance. The change of paradigm still turns out be an utopia, not wholly shared by everyone concerned, yet searched for by the majority.

[Nursing and the course in psychiatric nursing: the students' view]. / A enfermagem e a disciplina enfermagem psiquiátrica: visão da aluna.

This study shows an outline of the students of 6th and 8th semester in the Nursing School of Universidade Federal do Ceará, specially with respect to nursing, detaching aspects of conception about nursing, nursing assistance and, about the Psychiatric Nursing course. It regards the expectations and contributions of this discipline at the student professional formation and personal growth.

[Scientific production in nursing in northeastern Brazil (1988-1992)]. / Produção científica de enfermagem na região nordeste (1988-1992).

Descriptive exploratory study accomplished with the purpose of identifying nurses' scientific productions in the Northeast Region during the period of 1988-1992, checking the rind of papers presented, the predominating theme area and the divulgation used. We observe that there is a sensitive increase in these productions since 1990. Scientific articles and assistentcal area themes predominated, as did the divulgation through national events.