



@article {3321,
	title = {Natriuretic peptide system modulation in uninephrectomized rats},
	journal = {Experimental and Clinical Cardiology},
	volume = {20},
	year = {2014},
	note = {Export Date: 21 November 2014},
	month = {2014},
	pages = {2368 - 2387},
	abstract = {BACKGROUND: Cardiac activation of the natriuretic peptide (NP) system plays a major role in the renal adaptations to volume, expansion (VE). However, its role after uninephrectomy (Unx) remains to be elucidated. In the present study, we evaluated cardiac hemodynamics, plasma NP-Type B (BNP) levels nd NP receptor A (NPR-A) and C (NPR-C) expression in the renal cortex (RC) and medulla (RM) of Sham and Unx rats. METHODS: Male Wistar-Han rats (n=42) were randomly assigned to Unx or Sham surgery. Non-invasive blood pressure (BP), invasive left ventricular (LV) hemodynamics and natriuretic response to VE were performed and plasma was collected for BNP determination, 2, 10 and 26 weeks after surgery. In addition, samples from RC and RM were obtained for NPR-A and -C quantification (RT-PCR and western-blot). RESULTS: In Unx, blood pressure elevation and reduced natriuretic response to VE were observed. Although plasma BNP levels increased overtime, no LV dysfunction or myocardial BNP gene activation was observed in Unx. NPR-A mRNA in RC and RM were significantly increased in Unx at 26 weeks. This was accompanied by decreased NPR-C mRNA in the RM in Unx at 10 and 26 weeks, with no differences detected in the RC. CONCLUSIONS: In our experimentalmodel of Unx, progressive BP elevation and reduced natriuretic response to VE were accompanied by modulation of NPR-A and -C expression, in both the RC and RM, in the absence of cardiac activation of the NP system. Our results suggest a local renal modulation of the NP system after Unx. {\textcopyright} 2013 et al.; licensee Cardiology Academic Press.},
	keywords = {BNP, Hypertension, Natriuretic peptide receptor, Uninephrectomy},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84905968553\&partnerID=40\&md5=54369af569474ee0bfddfa5aeac3237a},
	author = {Santos-Ara{\'u}jo, C. and Roncon-Albuquerque Jr., R. and Moreira-Rodrigues, M. and Henriques-Coelho, T. and Quelhas-Santos, J. and Faria, B. and Sampaio-Maia, B. and Leite-Moreira, A.F. and Pestana, M.}
}
@article {2868,
	title = {Comparison of different methods of heart rate entropy analysis during acute anoxia superimposed on a chronic rat model of pulmonary hypertension},
	journal = {Medical Engineering and Physics},
	volume = {35},
	year = {2013},
	note = {Cited By (since 1996):1Export Date: 12 December 2013Source: Scopus},
	month = {2013///},
	pages = {559 - 568},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84877632838\&partnerID=40\&md5=05c9ef6d6fea4a96d6a63f1749251066},
	author = {Gon{\c c}alves, H. and Henriques-Coelho, T. and Rocha, A.P. and Louren{\c c}o, A.P. and Leite-Moreira, A. and Bernardes, J.}
}
@article {2260,
	title = {Analysis of heart rate variability in a rat model of induced pulmonary hypertension},
	journal = {Medical Engineering and PhysicsMed. Eng. Phys.},
	volume = {32},
	year = {2010},
	note = {Cited By (since 1996): 1Export Date: 21 November 2012Source: ScopusCODEN: MEPHEdoi: 10.1016/j.medengphy.2010.04.018PubMed ID: 20547091Language of Original Document: EnglishCorrespondence Address: Gon{\c c}alves, H.; Departamento de Geoci{\^e}ncias, Ambiente e Ordenamento do Territ{\'o}rio, Faculdade de Ci{\^e}ncias, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal; email: hernani.goncalves@fc.up.ptChemicals/CAS: monocrotaline, 315-22-0, 8051-27-2; Ketamine, 6740-88-1; Monocrotaline, 315-22-0References: (2005), ACOG, American College of Obstetricians and Gynecologists. ACOG Practice Bulletin. Clinical Management Guidelines for Obstetrician-Gynecologists, Number 70, December 2005. Obstet Gynecol 106(6):1453-60Akhavein, F., St.-Michel, E.J., Seifert, E., Rohlicek, C.V., Decreased left ventricular function, myocarditis, and coronary arteriolar medial thickening following monocrotaline administration in adult rats (2007) J Appl Physiol, 103 (1), pp. 287-295;Beckers, F., Verheyden, B., Aubert, A.E., Aging and nonlinear heart rate control in a healthy population (2006) Am J Physiol Heart Circ Physiol, 290 (6), pp. H2560-H2570; 
Bernardes, J., Costa-Pereira, A., A more objective fetal heart rate baseline estimation (1996) Br J Obstet Gynaecol, 103, pp. 714-715; 
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Dudewicz, E., Mishra, S., (1988) Modern mathematical statistics, , Jonh Wiley and Sons, Inc; 
Falcao-Pires, I., Gon{\c c}alves, N., Henriques-Coelho, T., Roncon-Albuquerque, R., Moreira-Gon{\c c}alves, D., Leite-Moreira, A.F., Administration of Apelin modulates myocardial. expression of Apelin-APJ and improves right ventricular performance in MCT-induced pulmonary hypertension (2008) Circulation, 118, pp. S285; 
Gon{\c c}alves, H., Rocha, A.P., Ayres-de-Campos, D., Bernardes, J., Internal versus external intrapartum foetal heart rate monitoring: the effect on linear and nonlinear parameters (2006) Physiol Meas, 27 (3), pp. 307-319; 
Gon{\c c}alves, H., Rocha, A.P., Ayres-de-Campos, D., Bernardes, J., Linear and nonlinear fetal heart rate analysis of normal and acidemic fetuses in the minutes preceding delivery (2006) Med Biol Eng Comput, 44 (10), pp. 847-855; 
Gon{\c c}alves, H., Bernardes, J., Rocha, A.P., Ayres-de-Campos, D., Linear and nonlinear analysis of heart rate patterns associated with fetal behavioral states in the antepartum period (2007) Early Hum Dev, 83, pp. 585-591; 
Gon{\c c}alves, H., Henriques-Coelho, T., Bernardes, J., Rocha, A.P., Nogueira, A., Leite-Moreira, A., Linear and nonlinear heart rate analysis in a rat model of acute anoxia (2008) Physiol Meas, 29, pp. 1133-1143; 
Henriques-Coelho, T., Correia-Pinto, J., Roncon-Albuquerque, R., Baptista, M.J., Lourenco, A.P., Oliveira, S.M., Endogenous production of ghrelin and beneficial effects of its exogenous administration in monocrotaline-induced pulmonary hypertension (2004) Am J Physiol Heart Circ Physiol, 287 (6), pp. H2885-H2890; 
Henriques-Coelho, T., Oliveira, S.M., Moura, R.S., Roncon-Albuquerque, R., Neves, A.L., Santos, M., Thymulin inhibits monocrotaline-induced pulmonary hypertension modulating interleukin-6 expression and suppressing p38 pathway (2008) Endocrinology, 149 (9), pp. 4367-4373; 
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Oppenheimer, L.W., Lewinsky, R.M., Power spectral analysis of fetal heart rate (1994) Baillieres Clin Obstet Gynaecol, 8 (3), pp. 643-661; 
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Pincus, S., Viscarello, R., Approximate Entropy: A regularity measure for fetal heart rate analysis (1992) Obstet Gynecol, 79, pp. 249-255; 
Pincus, S., Aproximate entropy (ApEn) as a complexity measure (1995) Chaos, 5, pp. 110-117; 
Pincus, S.M., Gevers, E.F., Robinson, I.C.A.F., VanDenBerg, G., Roelfsema, F., Hartman, M.L., Females secrete growth hormone with more process irregularity than males in both humans and rats (1996) Am J Physiol-Endocrinol Metab, 270 (1), pp. E107-E115; 
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Sanyal, S.N., Ono, K., Derangement of autonomic nerve control in rat with right ventricular failure (2002) Pathophysiology, 8 (3), pp. 197-203; 
Signorini, M.G., Magenes, G., Cerrutti, S., Arduini, D., Linear and nonlinear parameters for the analysis of fetal heart rate signal from cardiotacographic recordings (2003) IEEE Trans Biomed Eng, 50, pp. 365-373; 
(1996), Task force, Heart rate variability - standards of measurement, physiological interpretation and clinical use Circulation 93 1043-65 Task force of the European Society of Cardiology and the North American Society of Pacing and ElectrophysiologyTaylor, J.A., Studinger, P., Cardiovascular variability is/is not an index of autonomic control of circulation (2006) J Appl Physiol, 101 (2), pp. 690-691; 
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Yum, M.K., Park, E.Y., Kim, C.R., Hwang, J.H., Alterations in irregular and fractal heart rate behavior in growth restricted fetuses (2001) Eur J Obstet Gynecol, 94, pp. 51-58
},
	month = {2010///},
	pages = {746 - 752},
	abstract = {Monocrotaline (MCT) is commonly used to experimentally induce pulmonary hypertension (PH), which might lead to chronic heart failure. In this study, linear and non-linear heart rate (HR) dynamics were weekly assessed in MCT-treated and non-treated Wistar rats.The HR of 10 adult Wistar rats injected with MCT (MCT group) and of 10 similar rats injected with vehicle (non-MCT group), anesthetized with Ketamine, was weekly recorded during 4 weeks. The first four segments of 1-min length of each HR recording were analysed using linear, time and frequency domains, and approximate (ApEn) and sample (SampEn) entropy indices, considering recently proposed values for the threshold parameter of ApEn and SampEn. Statistical analysis was performed using 95\% confidence intervals and statistical tests.Along the study period, an overall weekly maintenance of HR indices, or a decrease, namely in weeks 1-2, was manifest, in the MCT group, except for LF and LF/HF, in week 1, denoting a short-term increase in sympathetic activity without any other changes. On the other hand, a maintenance of HR indices, or an increase, namely on week 4, was observed in the non-MCT group, except for LF/HF, denoting a long-term increase of the overall activity of HR control systems, with a parasympathetic like dominance.Studies on long-term HR dynamics should be performed in very carefully controlled experimental settings, as significant weekly changes may occur, both among anesthetized MCT-treated and non-treated rats. {\textcopyright} 2010 IPEM.},
	keywords = {adrenergic activity, Amines, animal experiment, animal model, Animals, article, cholinergic activity, Chronic heart failures, Confidence interval, controlled study, Disease Models, Animal, Electrocardiography, entropy, Female, Frequency domain analysis, Frequency domains, Heart, heart electrophysiology, Heart rate, Heart rate variability, Heart rate variability (HRV), Heart rates, Hypertension, Pulmonary, Injections, Subcutaneous, Ketamine, Maintenance, Monocrotaline, Non-linear, nonhuman, priority journal, Pulmonary hypertension, rat, Rat model, Rats, Rats, Wistar, Statistical analysis, statistical parameters, Sympathetic activities, Threshold parameters, Time and frequency domain analysis, Time domain analysis, Time Factors, Wistar rat, Wistar rats},
	isbn = {13504533 (ISSN)},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77955279673\&partnerID=40\&md5=5fa2879d821f37e48f50a723fa1cb225},
	author = {Gon{\c c}alves, H. and Henriques-Coelho, T. and Bernardes, J. and Rocha, A.P. and Brand{\~a}o-Nogueira, A. and Leite-Moreira, A.}
}
@article {2339,
	title = {Linear and nonlinear heart-rate analysis in a rat model of acute anoxia},
	journal = {Physiological MeasurementPhysiol. Meas.},
	volume = {29},
	year = {2008},
	note = {Cited By (since 1996): 6Export Date: 21 November 2012Source: ScopusCODEN: PMEAEdoi: 10.1088/0967-3334/29/9/010PubMed ID: 18784391Language of Original Document: EnglishCorrespondence Address: Gon{\c c}alves, H.; Departamento de Matem{\'a}tica Aplicada, Faculdade de Ci{\^e}ncias, Universidade Do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal; email: hernani.goncalves@fc.up.ptReferences: American College of Obstetricians and Gynecologists. ACOG Practice Bulletin. Clinical Management Guidelines for Obstetrician-Gynecologists, Number 70, December 2005 (2005) Obstet. Gynecol., 106, pp. 1453-1460;Ayres-De-Campos, D., Bernardes, J., Garrido, A., Marques-De-S{\'a}, J., Pereira-Leite, L., SisPorto 2.0: A program for automated analysis of cardiotocograms (2000) J. Mat. Fet. Med., 9 (5), pp. 311-318; 
Ayres-De-Campos, D., Santos, C., Bernardes, J., Prediction of neonatal state by computer analysis of fetal heart rate tracings: The antepartum arm of the SisPorto{\textregistered} validation study (2005) Eur. J. Obstet. Gynecol. Reprod. Biol., 118 (1), pp. 52-60; 
Beckers, F., Verheyden, B., Aubert, A.E., Aging and nonlinear heart rate control in a healthy population (2006) Am. J. Physiol. Heart Circ. Physiol., 290 (6), pp. 2560-H2570; 
Beckers, F., Verheyden, B., Ramaekers, D., Swinghedauw, B., Aubert, A.E., Effects of autonomic blockade on non-linear cardiovascular variability indices in rats (2006) Clin. Exp. Pharmacol. Physiol., 33 (5-6), pp. 431-439; 
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Cerutti, C., Gustin, M.P., Paultre, C.Z., Lo, M., Julien, C., Vincent, M., Sassard, J., Autonomic nervous-system and cardiovascular variability in rats-a spectral-analysis approach (1991) Am. J. Physiol., 261, pp. 1292-H1299; 
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Felgueiras, C., Marques-De-S{\'a}, J.P., Bernardes, J., Gama, S., Fractal characterisation of fetal heart rate sequences (1998) Biomedical Eng., 36, pp. 197-201; 
Gon{\c c}alves, H., Bernardes, J., Rocha, A.P., Ayres-De-Campos, D., Linear and nonlinear analysis of heart rate patterns associated with fetal behavioral states in the antepartum period (2007) Early Human Develop., 83 (9), pp. 585-591; 
Gon{\c c}alves, H., Rocha, A.P., Ayres-De-Campos, D., Bernardes, J., Internal versus external intrapartum foetal heart rate monitoring: The effect on linear and nonlinear parameters (2006) Physiol. Meas., 27 (3), pp. 307-319; 
Gon{\c c}alves, H., Rocha, A.P., Ayres-De-Campos, D., Bernardes, J., Linear and nonlinear fetal heart rate analysis of normal and acidemic fetuses in the minutes preceding delivery (2006) Med. Biol. Eng. Comput., 44 (10), pp. 847-855; 
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Kuwahara, M., Yayou, K., Ishii, K., Hashimoto, S., Tsubone, H., Sugano, S., Power spectral analysis of heart rate variability as a new method for assessing autonomic activity in the rat (1994) J. Electrocardiology, 27 (4), pp. 333-337; 
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Louren{\c c}o, A.P., Roncon-Albuquerque, R., Bras-Silva, C., Faria, B., Wieland, J., Henriques-Coelho, T., Correia-Pinto, J., Leite-Moreira, A.F., Myocardial dysfunction and neurohumoral activation without remodeling in left ventricle of monocrotaline-induced pulmonary hypertensive rats (2006) Am. J. Physiol. Heart Circ. Physiol., 291 (4), pp. 1587-H1594; 
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Martinez, W.L., Martinez, A.R., (2002) Computational Statistics Handbook with MATLAB; 
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Pincus, S.M., Gevers, E.F., Robinson, I.C.A.F., Vandenberg, G., Roelfsema, F., Hartman, M.L., Veldhuis, J.D., Females secrete growth hormone with more process irregularity than males in both humans and rats (1996) Am. J. Physiol., 270, pp. 107-E115; 
Pincus, S., Viscarello, R., Approximate Entropy: A regularity measure for fetal heart rate analysis (1992) Obstet. Gynecol., 79, pp. 249-255; 
Richman, J.S., Moorman, J.R., Physiological time-series analysis using approximate entropy and sample entropy (2000) Am. J. Physiol. Heart Circ. Physiol., 278, pp. 2039-H2049; 
Signorini, M.G., Magenes, G., Cerrutti, S., Arduini, D., Linear and nonlinear parameters for the analysis of fetal heart rate signal from cardiotacographic recordings (2003) IEEE Trans. Biomed. Eng., 50 (3), pp. 365-373; 
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Vieira, P., Marques-De-S{\'a}, J.P., Bernardes, J., Fractal analysis of foetal heart rate (2004) Proc. Biosignal 2004, pp. 53-55
},
	month = {2008///},
	pages = {1133 - 1143},
	abstract = {The objective of this study was the assessment of heart-rate (HR) dynamics with linear and nonlinear methods during episodes of mechanical ventilation and acute anoxia in rats. Namely, to assess whether linear and nonlinear HR analysis was able to discriminate acute anoxia from baseline in rats and if this was consistent with human foetal and adult studies. Five HR segments of 1 min duration, during baseline recording, mechanical ventilation and first, second and third minutes of induced acute anoxia, were analysed in ten adult Wistar rats. Linear time and frequency domain and nonlinear methods were used, namely mean HR (mHR), long-term irregularity (LTI), interval index (II), low frequency (LF) and high frequency (HF), approximate entropy (ApEn) and sample entropy (SampEn). New parameters for the entropy indices are proposed for the analysis of rats{\textquoteright} HR. Bootstrap percentile confidence intervals and nonparametric statistical tests were used in the evaluation of the differences between segments. During mechanical ventilation a clear spectral band was detectable at the ventilation rate, but mHR, II and the {\textquoteright}new{\textquoteright} entropy indices were the only significantly changed indices. In the transition from baseline-mechanical- ventilation to mechanical-ventilation-induced anoxia, a statistically significant decrease of mHR, II and entropy indices was observed, clearly discriminating these two instances, whereas most linear indices increased. With continued anoxia, most linear indices decreased significantly, whereas entropy remained stably low. These results are consistent with other foetal human and non-human studies and evidence that the rat model may be used for further research on linear and nonlinear analysis of heart-rate dynamics. The transition from baseline to acute anoxia was encompassed by signs of increased activation of the autonomic nervous system sympathetic branch, and decreased or blunted activity of the HR complexity regulatory centres. {\textcopyright} 2008 Institute of Physics and Engineering in Medicine.},
	keywords = {acute disease, animal experiment, animal model, Animals, Anoxia, article, artificial ventilation, bootstrapping, controlled study, entropy, Female, Fetal monitoring, frequency analysis, Heart rate, Heart rate variability, Humans, Linear analysis, linear system, lung ventilation, Models, Cardiovascular, nonhuman, nonlinear system, priority journal, rat, Rats, Rats, Wistar, Rattus, Rattus norvegicus, Respiration, Artificial, Statistical analysis, Variability, Wistar rat, Wistar rats},
	isbn = {09673334 (ISSN)},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-51849120545\&partnerID=40\&md5=56be327bb0d959060a2f4a0f080ae264},
	author = {Gon{\c c}alves, H. and Henriques-Coelho, T. and Bernardes, J. and Rocha, A.P. and Nogueira, A. and Leite-Moreira, A.}
}
