The evolution of ADAM gene family in eukaryotes.

The ADAM (A Disintegrin And Metalloprotease) gene family encodes proteins with adhesion and proteolytic functions. ADAM proteins are associated with diseases like cancers. Twenty ADAM genes have been identified in humans. However, little is known about the evolution of the family. We analyzed the repertoire of ADAM genes in a vast number of eukaryotic genomes to clarify the main gene copy number expansions. For the first time, we provide compelling evidence that early-branching green algae (Mamiellophyceae) have ADAM genes, suggesting that they originated in the last common ancestor of eukaryotes, before the split of plants, fungi and animals. The ADAM family expanded in early metazoans, with the most significative gene expansion happening during the first steps of vertebrate evolution. We concluded that most of mammal ADAM diversity can be explained by gene duplications in early bone fish. Our data suggest that ADAM genes were lost early in green plant evolution.

Inter-sexual habitat and isotopic niche segregation of the endangered Monteiro's storm-petrel during breeding.

At-sea distribution and trophic ecology of small seabird species (i.e.<100 g) is far less known when compared to their larger relatives. We studied the habitat use (spatial ecology) and isotopic niches (trophic ecology) of the endangered Monteiro's storm-petrel Hydrobates monteiroi during the incubation and chick-rearing periods of 2013. There was a sexual foraging segregation of Monteiro's storm-petrels during the breeding period (tracking data) but also during the non-breeding stage (stable isotope analysis). Females took advantage of their longer wings to forage over the shallower Mid-Atlantic ridge (MAR) north of Azores, under colder and windier regimes when compared to males, who mostly exploited northern deep waters comparatively closer to the breeding colony. Between-sex differences in the spatial distribution were more obvious during the incubation period, with the overlap in their distribution increasing during the chick-rearing phase. There was also an isotopic segregation between sexes both during the previous breeding and the non-breeding stages, with females exhibiting a narrower, lower level isotopic niche when compared to males. Though the distribution patterns reported here should be useful for the at-sea conservation of this endangered species, future research should focus on (1) performing year-round tracking to map the species' distribution during the non-breeding period and (2) gathering multi-year tracking information to understand the effect of inter-annual environmental stochasticity on the foraging choices and trophic habits of the species.

Regulation of Reactionary Dentine Formation.

During the treatment of dental caries that has not penetrated the tooth pulp, maintenance of as much unaffected dentine as possible is a major goal during the physical removal of decayed mineral. Damage to dentine leads to release of fossilized factors (transforming growth factor-ß [TGF-ß] and bone morphogenic protein [BMP]) in the dentine that are believed to stimulate odontoblasts to secrete new "tertiary" dentine (reactionary dentine). This is formed on the pulpal surface of existing dentine and rethickens the dentine. We have previously shown that activation of Wnt/ß-catenin signaling is pivotal for tooth repair in exposed pulp injury, and the pathway can be activated by small-molecule GSK-3 antagonists, resulting in enhanced reparative dentine formation. Here, we use a nonexposed pulp injury model to investigate the mechanisms of reactionary dentine formation in vivo, using small molecules to modulate the Wnt/ß-catenin, TGF-ß, and BMP pathways. We found that a local increase of Wnt activation at the injury site enhances reactionary dentine secretion. In addition, inhibition of TGF-ß, BMP, or Wnt pathways does not impede reactionary dentine formation, although inhibition of TGF-ß and/or BMP signaling does result in more disorganized, nontubular reactionary dentine. This suggests that Wnt/ß-catenin signaling plays no major role in the formation of reactionary dentine, but in common with reparative dentine formation, exogenous elevation of Wnt/ß-catenin signaling can enhance tertiary dentine formation. Release of latent TGF-ß or BMPs from dentine is not required for the deposition of mineral to form reactionary dentine but does play a role in its organization.

Quality of life related to oral mucositis of patients undergoing haematopoietic stem cell transplantation and receiving specialised oral care with low-level laser therapy: a prospective observational study.

Oral mucositis is a painful condition that occurs in 80% of patients who undergo haematopoietic stem cell transplantation (HSCT). Our objective was to determine the impact of mucositis on quality of life (QoL) of patients subjected to HSCT treated with low-level laser therapy (LLLT). Patients were evaluated: (1) on the first day of treatment; (2) 5 days after autologous or 8 days after allogeneic transplantation; (3) once bone marrow had integrated; and (4) 30 days after discharge. Clinical evaluation was performed using the World Health Organization criteria; oral health QoL was measured using the Oral Health Impact Profile (OHIP-14); and mucositis symptoms with the Patient-Reported Oral Mucositis Symptom (PROMS) scale. The higher the score, the lower the patient's QoL. The OHIP-14 responses showed that at D + 5/D + 8, all domains had the highest scores, while at times 1 and 4, the scores were lower. In the PROMS scale, all domains scored worst at time 2, and the differences between the scores at the four times were statistically significant. The study has shown that QoL improves over time in patients undergoing LLLT therapy for mucositis prevention.

Artrite reumatoide fator antinuclear positivo / Rheumatoid arthritis with positivity for antinuclear antibody

Objetivos: Verificar a prevalência de FAN positivo em portadores de AR e estudar a sua correlação com elementos clínicos. Material e Métodos: Foram estudados 113 pacientes portadores de AR quanto à idade do diagnóstico, sexo, presença de nódulos reumatóides, presença de alterações radiológicas (osteoporose justa articular e erosões) em RX de mãos, presença de fator reumatoide. Estes dados foram correlacionados com a presença do FAN. Resultados: A prevalência de FAN positivo foi de 21,24%, sem diferença estatisticamente significativa entre os sexos (p=0,553). Os títulos variaram entre 1:40 e 1:320, sendo a maioria (83,3%) padrão pontilhado. Não houve significância estatística entre o FAN positivo e idade de início da doença (p=0,4611) ou presença de alterações radiológicas (p=0,4397). Houve correlação significante entre FAN positivo e presença de nódulos reumatoides, onde 50% dos pacientes com nódulos tinham este anticorpo(p=0,0197). Conclusão: O presente estudo concluiu que os pacientes com AR nodular possuíam mais FAN positivo, o que pode ser indicativo de associação deste anticorpo com doença mais grave.

Objective: To verify the prevalence of ANA in patients with RA and study its correlation with clinical findings. Material and Methods: We studied 113 patients with rheumatoid arthritis for diagnosis age, sex, rheumatoid nodules, radiologic findings in hand X-rays and rheumatoid factor. These results were correlated with the presence of ANA. Results: About 21.24% of the patients had positive ANA and no significant gender differenceswere observed. The titers were between 1:40 to 1:320 and most of them (83.3%) with mottled pattern. No statistical significance could be found among ANA positive patients with regards to age of diagnosis (p=0.46) or radiological findings (p=0.43). There was a positive correlation of presence of rheumatoid nodules and finding of positive ANA (p=0.01). Conclusion: We conclude that patients with nodular RA have more frequently positive ANA, which can indicate that this antibody is present in more severe disease.

Distúrbios de humor em pacientes com lupus eritematoso sistêmico / Mood disorders in patients with lupus erythematosus

Objetivo: Estudar a prevalência de alterações de humor em pacientes com LES procurando relacioná-las com a percepção global de saúde. Metodologia: Estudaram-se 84 pacientes com LES e 84 pessoas saudáveis para depressão pela escala de Beck e ansiedade pela escala de Hamilton. No grupo com LES, obtiveram-se a percepção global da própria saúde por escala visual analógica. Resultados: Pacientes com LES obtiveram maiores resultados na escala de ansiedade (p=0,05); mas não na de depressão (p=0,65). O grau de ansiedade era maior naqueles pacientes com mais idade (p= 0,015) mas não nos com maior tempo de doença (p=0,73). Não se encontrou associação do grau de ansiedade com estado civil ou escolaridade do paciente. Todavia, o grau de ansiedade se correlacionou de maneira negativa com a percepção global da saúde (p=0,0023). Conclusões: Pacientes com LES sofrem mais de ansiedade do que a população normal. Este achado é mais comum nos pacientes mais idosos e naqueles que percebem a sua saúde como pior.

Objective: To study the prevalence of humor disturbances in patients with SLE trying to correlate them with the global perception of health. Methods: We studied 84 patients with SLE and 84 controls for depression scale of Beck and anxiety scale of Hamilton. In the SLE group we obtained the global perception of health through an analogical visual scale. Results: Patients with SLE obtained higher scores in anxiety scale (p=0.05) but not in depression scale (p=0.65). The anxiety degree correlated with patient's age but not with disease duration, degree of formal education or civil estate. However the degree of anxiety correlated in a negative way with global perception of health (p=0.0023). Conclusion: Patients with SLE suffer more from anxiety than the normal population.

Efeitos colaterais oculares dos antimaláricos / Antimalarial ocular side effects

Introdução: A cloroquina e a hidroxicloroquina são medicamentos amplamente utilizados para tratamento das doenças do tecido conjuntivo como artrite reumatóide, lúpus eritematoso sistêmico, Síndrome de Sjögren e osteoartrite mãos. Seus efeitos colaterais mais temidos são os oculares: depósitos corneais e retinopatia. Material e métodos: Foram estudados os prontuários dos pacientes portadores de artrite reumatoide do ambulatório de reumatologia do Hospital Evangélico de Curitiba e usuários de antimaláricos (total de 167) para alterações oculares secundárias ao medicamento. Resultados: Em 5 pacientes existia diagnóstico de maculopatia e em 4 o diagnóstico de ceratopatia por cloroquina, com associação positiva para idade avançada e com tempo de uso. Conclusão: A ceratopatia e maculopatia por antimaláricos ocorreram em pequena proporção de usuários de cloroquina (2,4% e 3% respectivamente), não sendo encontrado este efeito adverso nos usuários de hidroxicloroquina.

Chloroquine and hydroxychloroquine are widely used drugs indicated for treatment of connective tissue diseases such as rheumatoid arthritis, systemic lupus erythematosus, Sjogren´s syndrome and hand osteoarthritis. The most feared side effects of these medications are corneal deposits and maculopathy. Material and methods: We reviewed the charts of 167 patients with rheumatoid arthritis from rheumatology unit of Hospital Evangélico de Curitiba for ocular side effects of this medication. Results: There was maculopathy in 5 patients using chloroquine and in 4 of them, there was ceratopathy. This finding had a positive association with older age and prolonged use of this medication. Conclusions: Antimalarial cerathopathy and maculopathy occurred in a small proportion of cloroquine users (2,4 and 3% respectively). These side effects weren't found in hydroxylchlroquine patients.

Prevalência de alterações cognitivas em uma população com lupus eritematoso sistêmico / Prevalence of cognitive disorders in a systemic lupus erythematosus population

Objetivo: estudar a prevalência de alterações cognitivas em pacientes com lúpus eritematoso sistêmico (LES) comparando-a com a de população saudável. Métodos: Foram aplicados 168 questionários a 84 pacientes portadores de LES e 84 controles. O questionário era composto da escala de Beck para depressão, mini-mental e escala de Hamilton para ansiedade, assim como determinação da percepção da saúde global através de escala visual analógica. Dados clínicos e demográficos foram coletados dos prontuários. Resultados: Pacientes com LES mostraram resultados significativamente inferiores no mini-mental (p=0,0065) do que os controles. Esta diminuição mostrou correlação com o grau de ansiedade (p=0,002), mas não com o de depressão (0,06). Observou-se também correlação entre alteração do mini-mental e percepção global de saúde (p=0,03). Conclusão: Pacientes com LES têm mais alterações cognitivas que a população normal. O grau dessas alterações está associado ao grau de ansiedade e percepção global de saúde.

Objective: To study the prevalence of cognitive impairment in a group of systemic lupus erythematosus (SLE) patients comparing them with normal population. Methods: We applied 168 questionnaires to 84 lupus patients and 84 controls. The questioner included demographic date, Beck scale for depression, mini-mental, Hamilton scale for anxiety as well as determination of global health state by analogical visual scale. Results: Patients with SLE scored significantly lower in mini-mental as controls (p=0,0065). This results showed a correlation with the degree of anxiety (p=0,002) but not with depression (0,006). We also observed correlation between mini-mental results and global health perception (p=0,003). Conclusion: Patients with SLE have more cognitive impairment than normal population. The degree of such alterations is related with the degree of anxiety and global perception of health.

Prevalência de doenças de autoimunidade em pacientes com tireoidite de Hashimoto / Autoimmunity diseases prevalence in patients with Hashimoto

Objetivo: Avaliar a prevalência de tais doenças em pacientes com tireoidite de Hashimoto (TH). Métodos: Foi utilizada uma amostra aleatória de 155 pacientes com TH, questionando-se idade, tempo de diagnóstico, existência de autoanticorpos tireoidianos e coexistência de outras doenças. Resultados: A amostra compunha-se de 135 mulheres e 20 homens, com idade média de 53 anos e duração média de doença de 6 anos. Existia positividade para anticorpo antitireoperoxidase (TPO) e 54,54% para antitireoglobulina (TG). Em 67,82% existia positividade para algum dos anticorpos antitireoidianos. Em 6,45% dos pacientes havia uma segunda doença associada, destes, em 40% artrite reumatóide, em 20% lúpus eritematoso sistêmico, em 10% polimiosite, em10% psoríase e em 10% retocolite ulcerativa. Uma paciente com AR tinha também esclerodermia associada. Conclusão: Concluiu-se que em TH existia uma prevalência de 6% de uma segunda doença de autoimunidade, o que é compatível com a literatura. Como o hipotireoidismo pode simular doenças reumáticas, esse conhecimento é importante no manejo correto destes pacientes.

Objective: It is to assess the prevalence of such diseases in patients with Hashimoto's thyroiditis (HT). Methods: We used a random sample of 155 patients with HT, questioning whether age, time of diagnosis, presence of thyroid autoantibodies and the coexistence of other diseases. Results: The sample consisted of 135 women and 20 men, with mean age was 53 years and with mean disease duration of 6 years. Eighty six percent were positive for anti-thyroperoxidase (TPO) and 54.54% for thyroglobulin (TG). In 67.82% existed at least one antithyroid antibody. In 6.45% of patients there was a second disease associated; 40% were reumatoid arthritis, 20% systemic lupus erythematosus, 10% polymyositis, 10% psoriasis and 10% of ulcerative colitis. One patient with RA had also 50 Prevalência de Doenças de Autoimunidade em Pacientes com Tireoidite de Hashimoto. scleroderma. Conclusion: We conclude that in TH there was a prevalence of 6% of a second autoimmune disease, which is according with the literature. Because hypothyroidism can mimic rheumatic diseases, such knowledge is important in the correct management of these patients.

Design of double-walled carbon nanotubes for biomedical applications.

Double-walled carbon nanotubes (DWNTs) prepared by catalytic chemical vapour deposition were functionalized in such a way that they were optimally designed as a nano-vector for the delivery of small interfering RNA (siRNA), which is of great interest for biomedical research and drug development. DWNTs were initially oxidized and coated with a polypeptide (Poly(Lys:Phe)), which was then conjugated to thiol-modified siRNA using a heterobifunctional cross-linker. The obtained oxDWNT-siRNA was characterized by Raman spectroscopy inside and outside a biological environment (mammalian cells). Uptake of the custom-designed nanotubes was not associated with detectable biochemical perturbations in cultured cells, but transfection of cells with DWNTs loaded with siRNA targeting the green fluorescent protein (GFP) gene, serving as a model system, as well as with therapeutic siRNA targeting the survivin gene, led to a significant gene silencing effect, and in the latter case a resulting apoptotic effect in cancer cells.

Chronic stress, but not hypercaloric diet, impairs vascular function in rats.

The aim of this study was to evaluate vascular and metabolic effects of chronic mild unpredictable stress (CMS) and hypercaloric diet (HD) without carbohydrate supplementation in rats. Male Sprague-Dawley rats were randomly assigned to four groups: Control, HD, CMS, and HD plus CMS. CMS consisted of the application of different stressors for 3 weeks. The rats were killed 15 days after CMS exposure. The HD group presented higher plasma lipid concentrations, without changes in fasting glucose concentration, glucose tolerance test, and vascular function and morphology, in comparison with the control group. Stressed rats presented higher fasting blood concentration of insulin, higher homeostasis model assessment index values and area under the curve in an oral glucose tolerance test, in comparison with non-stressed rats. CMS increased the plasma concentrations of corticosterone and lipids, and the atherogenic index values, without change in high-density lipoprotein level. CMS increased intima-media thickness and induced endothelium-dependent supersensitivity to phenylephrine, and lowered the relaxation response to acetylcholine in the thoracic aorta isolated from rats fed with control or HD, in comparison with non-stressed groups. CMS effects were independent of diet. In non-stressed rats, the HD induced dyslipidemia, but did not change glucose metabolism, vascular function, or morphology. The data from this study indicate that CMS promotes a set of events which together can contribute to impair function of the thoracic aorta.

AFM imaging of functionalized carbon nanotubes on biological membranes.

Multifunctional carbon nanotubes are promising for biomedical applications as their nano-size, together with their physical stability, gives access into the cell and various cellular compartments including the nucleus. However, the direct and label-free detection of carbon nanotube uptake into cells is a challenging task. The atomic force microscope (AFM) is capable of resolving details of cellular surfaces at the nanometer scale and thus allows following of the docking of carbon nanotubes to biological membranes. Here we present topographical AFM images of non-covalently functionalized single walled (SWNT) and double walled carbon nanotubes (DWNT) immobilized on different biological membranes, such as plasma membranes and nuclear envelopes, as well as on a monolayer of avidin molecules. We were able to visualize DWNT on the nuclear membrane while at the same time resolving individual nuclear pore complexes. Furthermore, we succeeded in localizing individual SWNT at the border of incubated cells and in identifying bundles of DWNT on cell surfaces by AFM imaging.

Proatherosclerotic effects of chronic stress in male rats: altered phenylephrine sensitivity and nitric oxide synthase activity of aorta and circulating lipids.

The aim of this study was to analyze the effects of chronic mild unpredictable stress (CMS) on the vasoconstrictor response and morphology of the thoracic aorta and serum lipid profiles in rats. Male Sprague-Dawley rats were submitted to CMS, which consisted of the application of different stressors for 7 days per week across 3 weeks. The rats were sacrificed 15 days after CMS exposure. CMS induced supersensitivity to the vasoconstrictor effect of phenylephrine in endothelium-intact thoracic aortic rings without changes in aortic rings without endothelium, or pre-incubated with nitric oxide (NO) synthesis inhibitor. Rats submitted to CMS showed hypertrophy of the intima and tunica media of thoracic aorta, increased serum levels of triglycerides, total cholesterol, very low-density lipoprotein cholesterol, low-density lipoprotein cholesterol and atherogenic index, without changes in high-density lipoprotein cholesterol levels, when compared with control rats. These data indicate that CMS induces physiological and morphological changes that may contribute to the development of atherosclerosis by mechanisms related to deficiency in NO production and dyslipidemia.

American visceral leishmaniasis: disease control strategies in Dracena microregion in Alta Paulista, SP, Brazil

Despite measures adopted to control American visceral leishmaniasis (AVL), the disease is spreading in a fast and worrying way throughout western São Paulo state. The aim of this work was to study the variables involved in the disease cycle as well as the effectiveness of controlling measures. The study was carried out in the microregion of Dracena, which is composed of twelve cities and belongs to Alta Paulista, a region of western São Paulo. The necessary data were provided by the Superintendence for Endemic Disease Control and Adolfo Lutz Institute, Regional Laboratory of Presidente Prudente. From August 2005 to January 2008, the following factors were observed: detection of phlebotomine sandflies in the cities and periods in which dogs or humans were diagnosed; number of human deaths; prevalence of suspected dogs tested by serology; percentage of euthanasia in suspected dogs; a possible correlation between positive dogs and cases of the disease in humans; and the disease prevalence among municipalities from the studied region. It was verified that, despite the strategies adopted in Dracena microregion to control AVL, the disease continues to rise. Thus, some procedures of the AVL Monitoring and Control Program should be reviewed, to grant the initiative more credibility and effectiveness.

Avaliação da qualidade de vida em idosos com demência e depressão

Foram avaliados 50 pacientes, 35 (70%) mulheres e 15 (30%) homens, com média de idade de 77,74 anos. Não houve diferença entre os grupos em relação ao índice de Pfeffer. O QOL-AD mostrou diferença estatisticamente significante entre os grupos com e sem depressão. Conclusão: a depressão é um fator importante de piora da qualidade de vida em idosos com demência de leve a moderada intensidade e deve ser tratada também nesses pacientes

Avaliação da qualidade de vida em idosos com demência e depressão / Assessment of quality of life in elderly people with dementia and depression

Foram avaliados 50 pacientes, 35 (70%) mulheres e 15 (30%) homens, com média de idade de 77,74 anos. Não houve diferença entre os grupos em relação ao índice de Pfeffer. O QOL-AD mostrou diferença estatisticamente significante entre os grupos com e sem depressão. Conclusão: a depressão é um fator importante de piora da qualidade de vida em idosos com demência de leve a moderada intensidade e deve ser tratada também nesses pacientes (AU)

Autonomic modulation of heart rate of young and postmenopausal women undergoing estrogen therapy.

The aim of the present study was to determine whether estrogen therapy (ET) reduces alterations of the autonomic control of heart rate (HR) due to hypoestrogenism and aging. Thirteen young (24 +/- 2.6 years), 10 postmenopausal (53 +/- 4.6 years) undergoing ET (PM-ET), and 14 postmenopausal (56 +/- 2.6 years) women not undergoing ET (PM) were studied. ET consisted of 0.625 mg/day conjugated equine estrogen. HR was recorded continuously for 8 min at rest in the supine and sitting positions. HR variability (HRV) was analyzed by time (SDNN and rMSSD indices) and frequency domain methods. Power spectral components are reported as normalized units (nu) at low (LF) and high (HF) frequencies, and as LF/HF ratio. Intergroup comparisons: SDNN index was higher in young (median: supine, 47 ms; sitting, 42 ms) than in PM-ET (33; 29 ms) and PM (31; 29 ms) women (P < 0.05). PM showed lower HFnu, higher LFnu and higher LF/HF ratio (supine: 44, 56, 1.29; sitting: 38, 62, 1.60) than the young group in the supine position (61, 39, 0.63) and the PM-ET group in the sitting position (57, 43, 0.75; P < 0.05). Intragroup comparisons: HR was lower in the supine than in the sitting position for all groups (P < 0.05). The HRV decrease from the supine to the sitting position was significant only in the young group. These results suggest that HRV decreases during aging. ET seems to attenuate this process, promoting a reduction in sympathetic activity on the heart and contributing to the cardioprotective effect of estrogen hormones.

Comparison of anaerobic threshold determined by visual and mathematical methods in healthy women.

Several methods are used to estimate anaerobic threshold (AT) during exercise. The aim of the present study was to compare AT obtained by a graphic visual method for the estimate of ventilatory and metabolic variables (gold standard), to a bi-segmental linear regression mathematical model of Hinkley's algorithm applied to heart rate (HR) and carbon dioxide output (VCO2) data. Thirteen young (24 +/- 2.63 years old) and 16 postmenopausal (57 +/- 4.79 years old) healthy and sedentary women were submitted to a continuous ergospirometric incremental test on an electromagnetic braking cycloergometer with 10 to 20 W/min increases until physical exhaustion. The ventilatory variables were recorded breath-to-breath and HR was obtained beat-to-beat over real time. Data were analyzed by the nonparametric Friedman test and Spearman correlation test with the level of significance set at 5%. Power output (W), HR (bpm), oxygen uptake (VO2; mL kg(-1) min(-1)), VO2 (mL/min), VCO2 (mL/min), and minute ventilation (VE; L/min) data observed at the AT level were similar for both methods and groups studied (P > 0.05). The VO2 (mL kg(-1) min(-1)) data showed significant correlation (P < 0.05) between the gold standard method and the mathematical model when applied to HR (rs = 0.75) and VCO2 (rs = 0.78) data for the subjects as a whole (N = 29). The proposed mathematical method for the detection of changes in response patterns of VCO2 and HR was adequate and promising for AT detection in young and middle-aged women, representing a semi-automatic, non-invasive and objective AT measurement.

Autonomic modulation of heart rate of young and postmenopausal women undergoing estrogen therapy

The aim of the present study was to determine whether estrogen therapy (ET) reduces alterations of the autonomic control of heart rate (HR) due to hypoestrogenism and aging. Thirteen young (24 ± 2.6 years), 10 postmenopausal (53 ± 4.6 years) undergoing ET (PM-ET), and 14 postmenopausal (56 ± 2.6 years) women not undergoing ET (PM) were studied. ET consisted of 0.625 mg/day conjugated equine estrogen. HR was recorded continuously for 8 min at rest in the supine and sitting positions. HR variability (HRV) was analyzed by time (SDNN and rMSSD indices) and frequency domain methods. Power spectral components are reported as normalized units (nu) at low (LF) and high (HF) frequencies, and as LF/HF ratio. Intergroup comparisons: SDNN index was higher in young (median: supine, 47 ms; sitting, 42 ms) than in PM-ET (33; 29 ms) and PM (31; 29 ms) women (P < 0.05). PM showed lower HFnu, higher LFnu and higher LF/HF ratio (supine: 44, 56, 1.29; sitting: 38, 62, 1.60) than the young group in the supine position (61, 39, 0.63) and the PM-ET group in the sitting position (57, 43, 0.75; P < 0.05). Intragroup comparisons: HR was lower in the supine than in the sitting position for all groups (P < 0.05). The HRV decrease from the supine to the sitting position was significant only in the young group. These results suggest that HRV decreases during aging. ET seems to attenuate this process, promoting a reduction in sympathetic activity on the heart and contributing to the cardioprotective effect of estrogen hormones.

Comparison of anaerobic threshold determined by visual and mathematical methods in healthy women

Several methods are used to estimate anaerobic threshold (AT) during exercise. The aim of the present study was to compare AT obtained by a graphic visual method for the estimate of ventilatory and metabolic variables (gold standard), to a bi-segmental linear regression mathematical model of Hinkley's algorithm applied to heart rate (HR) and carbon dioxide output (VCO2) data. Thirteen young (24 ± 2.63 years old) and 16 postmenopausal (57 ± 4.79 years old) healthy and sedentary women were submitted to a continuous ergospirometric incremental test on an electromagnetic braking cycloergometer with 10 to 20 W/min increases until physical exhaustion. The ventilatory variables were recorded breath-to-breath and HR was obtained beat-to-beat over real time. Data were analyzed by the nonparametric Friedman test and Spearman correlation test with the level of significance set at 5 percent. Power output (W), HR (bpm), oxygen uptake (VO2; mL kg-1 min-1), VO2 (mL/min), VCO2 (mL/min), and minute ventilation (VE; L/min) data observed at the AT level were similar for both methods and groups studied (P > 0.05). The VO2 (mL kg-1 min-1) data showed significant correlation (P < 0.05) between the gold standard method and the mathematical model when applied to HR (r s = 0.75) and VCO2 (r s = 0.78) data for the subjects as a whole (N = 29). The proposed mathematical method for the detection of changes in response patterns of VCO2 and HR was adequate and promising for AT detection in young and middle-aged women, representing a semi-automatic, non-invasive and objective AT measurement.