Cardiovascular Responses To Postural Change And Aerobic Capacity In Middle-aged Men And Women Before And After Aerobic Physical Training

Objective: To compare the cardiovascular responses to passive postural maneuvers (tilt test) and the cardiorespiratory capacity in middle-aged men and women, before and after aerobic physical training. Methods: Seven men (44.6±2.1 years old) and seven women (51.7±4.8 years old) participated in aerobic physical training for 12 weeks. The tilt test protocol (five minutes supine, ten minutes tilted at 70° and five minutes supine) was followed, with arterial blood pressure and heart rate monitoring. A cycle ergometer protocol was used to measure cardiorespiratory capacity. Results: In the sedentary condition, men showed greater parasympathetic influence in heart rate control, as demonstrated by their higher RR interval (iRR) during the tilt test. After training, the iRR values became more similar in the two groups, although the women had higher iRR in the supine position and the men continued to present higher iRR under tilted conditions. The women's blood pressures continued to be higher after training, but heart rate tended to become similar in the two groups. The cardiorespiratory capacity patterns in the two groups were similar after training. Except for absolute heart rate values, for which there were no differences between the groups, the men's values were higher than those of the women for all other variables. It was also observed that, after the training, the women's blood pressures were significantly lower, even though their pressures remained higher than the men's. Conclusions: The training seemed to reduce the women's arterial blood pressure levels and improve both groups' cardiorespiratory capacity, but the men continued to present better performance than the women.125392400Pollock, M.L., Dawson, G.A., Physiologic responses of men 49 to 65 years of age to endurance training (1976) J Am Geriatr Soc, 24 (3), pp. 97-104Haddock, B.L., Marshak, H.P.H., Mason, J.J., Blix, G., The effect of hormone replacement therapy and exercise on cardiovascular disease risk factors in postmenopausal women (2000) Sports Med, 29 (1), pp. 39-49Liu, C.C., Kuo, T.B., Yang, C.C., Effects of estrogen on gender-related autonomic differences in humans (2003) Am J Physiol Heart Circ Physiol, 285 (5), pp. H2188-H2193Rosano, G.M., Vitale, C., Fini, M., Hormone replacement therapy and cardioprotection: What is good and what is bad for the cardiovascular system? (2006) Ann. N.Y. Acad Sci, 1092, pp. 341-348Ghorayeb N, Baptista CA, Dioguardi GS, Reginatto LE. 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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.49149

Soil class map of the Rio Jardim watershed in Central Brazil at 30 meter spatial resolution based on proximal and remote sensed data and MESMA method

Geospatial soil information is critical for agricultural policy formulation and decision making, land-use suitability analysis, sustainable soil management, environmental assessment, and other research topics that are of vital importance to agriculture and economy. Proximal and Remote sensing technologies enables us to collect, process, and analyze spectral data and to retrieve, synthesize, visualize valuable geospatial information for multidisciplinary uses. We obtained the soil class map provided in this article by processing and analyzing proximal and remote sensed data from soil samples collected in toposequences based on pedomorphogeological relashionships. The soils were classified up to the second categorical level (suborder) of the Brazilian Soil Classification System (SiBCS), as well as in the World Reference Base (WRB) and United States Soil Taxonomy (ST) systems. The raster map has 30 m resolution and its accuracy is 73% (Kappa coefficient of 0.73). The soil legend represents a soil class followed by its topsoil color

Effect of temperature and copper doping on the heterogeneous Fenton-like activity of Cux_xFe3−x_{3-x}O4_4 nanoparticles

Ferrite nanoparticles serve as potent heterogeneous Fenton-like catalysts, producing reactive oxygen species (ROS) for decomposing organic pollutants. We investigated the impact of temperature and copper content on the catalytic activity of nanoparticles with different oxidation states of iron. Via solvothermal synthesis, we fabricated copper-doped magnetite (Cu$_x$Fe$_{3-x}$O$_4$) with a Fe$^{2+}$/Fe ratio ~0.33 for the undoped system. Using a microwave-assisted method, we produced copper-doped oxidized ferrites, yielding a Fe$^{2+}$/Fe ratio of ~0.11 for the undoped nanoparticles. The ROS generated by the catalyst were identified and quantified by electron paramagnetic resonance, while optical spectroscopy allowed us to evaluate its effectiveness for the degradation of a model organic dye. At room temperature, the magnetite nanoparticles exhibited the most $\cdot$OH radical production and achieved almost 90% dye discoloration in 2 hours. This efficiency decreased with increasing Cu concentration, concurrently with a decrease in $\cdot$OH generation. Conversely, above room temperature, Cu-doped nanoparticles significantly enhance the dye degradation, reaching 100% discoloration at 90$^\circ$C. This enhancement is accompanied by a systematic increase in the kinetic constants, obtained from reaction equations, with Cu doping. This study highlights the superior stability and high-temperature catalytic advantages of copper ferrite holding promise for enhancing the performance of nanocatalysts for decomposing organic contaminants.Comment: 40 pages, 11 figure

Comparison of cardiorespiratory responses between constant and incremental load exercises below, above and at the ventilatory anaerobic threshold

OBJECTIVE: To apply different analytical methodologies to data from continuous ramp tests (CRT) and discontinuous step tests (DST), and compare responses from cardiorespiratory parameters. METHOD: Eight men performed spirometric tests on an electrically braked cycle ergometer: CRT increasing from 20 to 25 W.min-1 and DST in 15-min steps, each based on the ventilatory anaerobic threshold (VAT) for CRT. Step 1 was 70% VAT; step 2, 100% VAT; and step 3, 130% VAT. VAT was determined as loss of parallelism between O2 uptake (VO2) and CO2 output (VCO2). Heart rate (HR, bpm), VCO2, VO2 (ml.min-1), VO2 (ml.kg.min-1) and ventilation (VE L.min-1) values for CRT were obtained as moving averages of eight breath-to-breath respiratory cycles, using linear regression. For DST, means were applied from the third to fifteenth minute of the steps. Statistical comparisons utilized the Kolmogorov-Smirnov test, ANOVA, post-hoc Tukey-Kramer test and linear regression, with significance limit of p0.05), but VO2 was different between VAT and all steps (p0,05), porém VO2 relativo foi diferente (p<0,05) entre LAV e todos os degraus; a FC mostrou diferença (p<0,05) entre LAV e degrau 3, e na análise entre os três degraus houve diferença (p<0,05). CONCLUSÃO: Os resultados indicam que a regressão linear foi eficaz para estimar as variáveis cardiorrespiratórias. Em relação aos protocolos, verificou-se que para a obtenção no TDD de valores cardiorrespiratórios similares ao LAV do TCR foi necessário diminuir a potência em 30%.16316

Proper Sterol Distribution Is Required for Candida albicans Hyphal Formation and Virulence

Candida albicans is an opportunistic fungus responsible for the majority of systemic fungal infections. Multiple factors contribute to C. albicans pathogenicity. C. albicans strains lacking CaArv1 are avirulent. Arv1 has a conserved Arv1 homology domain (AHD) that has a zinc-binding domain containing two cysteine clusters. Here, we explored the role of the CaAHD and zinc-binding motif in CaArv1-dependent virulence. Overall, we found that the CaAHD was necessary but not sufficient for cells to be virulent, whereas the zinc-binding domain was essential, as Caarv1/Caarv1 cells expressing the full-length zinc-binding domain mutants, Caarv1C3S and Caarv1C28S, were avirulent. Phenotypically, we found a direct correlation between the avirulence of Caarv1/Caarv1, Caarrv1AHD, Caarv1C3S, and Caarv1C28S cells and defects in bud site selection, septa formation and localization, and hyphal formation and elongation. Importantly, all avirulent mutant strains lacked the ability to maintain proper sterol distribution. Overall, our results have established the importance of the AHD and zinc-binding domain in fungal invasion, and have correlated an avirulent phenotype with the inability to maintain proper sterol distribution

"We can't carry the weight of the whole world": illness experiences among Peruvian older adults with symptoms of depression and anxiety

Background: Despite the high levels of depression and anxiety symptoms in old age, the use of mental health services in this population is low. Help-seeking behaviors are shaped by how an individual perceives and experiences their illness. The objective of this study was to characterize the illness experiences of Peruvian older adults with depression and anxiety symptoms in order to lay the foundation for tailored community-based mental health interventions. Methods: In this qualitative study, we conducted in-depth interviews with a purposively selected sample of older adults (≥ 60 years) from peri-urban areas of Lima, Peru. We included individuals with only depressive symptoms (Patient Health Questionnaire-9 ≥ 10), only anxiety symptoms (Beck Anxiety Inventory ≥ 16), with depressive and anxiety symptoms, and older adults who mentioned they had received mental health treatment/care. The interview guide included the following topics: perceptions and experiences about depression and anxiety; perceptions about the relationship between physical chronic diseases and mental health; experiences with mental health professionals and treatments, and coping mechanisms. Data collection was conducted between October 2018 and February 2019. Results: We interviewed 38 participants (23 women, 15 men) with a mean age of 67.9 years. Participants' ideas and perceptions of depression and anxiety showed considerable overlap. Participants attributed depression and anxiety mainly to familial and financial problems, loneliness, loss of independence and past traumatic experiences. Coping strategies used by older adults included 'self-reflection and adaptation' to circumstances, 'do your part', and seeking 'emotional support' mainly from non-professionals (relatives, friends, acquaintances, and religion). Conclusions: Illness experiences of depression and anxiety set the pathway for tailored community-based mental health interventions for older adults. Overlapping narratives and perceptions of depression and anxiety suggest that these conditions should be addressed together. Mental health interventions should incorporate addressing areas related to depression and anxiety such as prevention of loss of independence, trauma, and loneliness. Good acceptability of receiving emotional support for non-professionals might offer an opportunity to incorporate them when delivering mental health care to older adults