State University of Centro Oeste

Guarapuava, Brazil

State University of Centro Oeste

Guarapuava, Brazil
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Rossi L.P.,State University of Centro Oeste | Rossi L.P.,Federal University of Paraná | Pereira R.,State University of Southwest Bahia | Brandalize M.,Guairaca Faculty | Gomes A.R.S.,Federal University of Paraná
Human Movement | Year: 2013

Purpose. The purpose of this study was to evaluate the effects of short-term perturbation-based balance training and a detraining period on postural control in older adults. Methods. A group of healthy older women were recruited and divided into two groups: an exercise group (EG, n = 21, age = 67.0 ± 2.0 y) that performed balance-based exercises three times a week over a sixweek period and a control group (CG, n = 20, age = 67.9 ± 3.1 y). Center-of-pressure displacement (CoP) and electromyographic data (EMG onset, time-to-peak and amplitude) were assessed during forward and backward perturbations for six leg muscles. All variables were analyzed before the training program began, at its end, and after a six-week period of detraining. A mixed ANOVA model was used to analyze the within- and between-subject results. Results. A decrease in backward CoP displacement, EMG onset and time-to-peak of the ankle muscles, especially the tibialis anterior (TA) and gastrocnemius (MG), was observed. Improvement in muscle EMG amplitude for the ankle muscles (TA, MG and Soleus - SO) at the early phase (0-200 ms) of the perturbation test, with the SO also showing an increase in amplitude at the intermediate phase (201-400 ms). After the detraining period, only the TA muscle maintained an improvement in reaction time. Conclusions. Perturbation-based balance training improved neuromuscular responses such as muscle reaction time and ankle muscle activation and consequently aided the body's ability to maintain correct center of pressure, although after a period of detraining this gain was not maintained for most of the assessed variables.


Romano M.A.,University of Sao Paulo | Romano M.A.,State University of Centro Oeste | Wisniewski P.,State University of Centro Oeste | Viau P.,University of Sao Paulo | And 7 more authors.
Archives of Toxicology | Year: 2012

Sexual differentiation in the brain takes place from late gestation to the early postnatal days. This is dependent on the conversion of circulating testosterone into estradiol by the enzyme aromatase. The glyphosate was shown to alter aromatase activity and decrease serum testosterone concentrations. Thus, the aim of this study was to investigate the effect of gestational maternal glyphosate exposure (50 mg/kg, NOAEL for reproductive toxicity) on the reproductive development of male offspring. Sixty-dayold male rat offspring were evaluated for sexual behavior and partner preference; serum testosterone concentrations, estradiol, FSH and LH; the mRNA and protein content of LH and FSH; sperm production and the morphology of the seminiferous epithelium; and the weight of the testes, epididymis and seminal vesicles. The growth, the weight and age at puberty of the animals were also recorded to evaluate the effect of the treatment. The most important findings were increases in sexual partner preference scores and the latency time to the first mount; testosterone and estradiol serum concentrations; the mRNA expression and protein content in the pituitary gland and the serum concentration of LH; sperm production and reserves; and the height of the germinal epithelium of seminiferous tubules. We also observed an early onset of puberty but no effect on the body growth in these animals. These results suggest that maternal exposure to glyphosate disturbed the masculinization process and promoted behavioral changes and histological and endocrine problems in reproductive parameters. These changes associated with the hypersecretion of androgens increased gonadal activity and sperm production. © Springer-Verlag 2011.


Sleiman H.K.,State University of Centro Oeste | Romano R.M.,University of Sao Paulo | Oliveira C.A.D.,University of Sao Paulo | Romano M.A.,State University of Centro Oeste
Journal of Toxicology and Environmental Health - Part A: Current Issues | Year: 2013

The incidence of male reproductive pathologies, such as hypospadias, cryptorchidism, testicular cancer, and low sperm production in adulthood, is increasing and may be related to exposure to environmental contaminants. The silver nanoparticles (AgNP) are a new class of chemical compounds commonly used in both medical and nonmedical settings, and they affect development of spermatogonial stem cells in vitro. The aim of this study was to examine the adverse productive toxic effects of AgNPs in male Wistar rats exposed during the prepubertal period and sacrificed at postnatal day (PND) 53 and PND90. Growth was assessed by daily weighing. The progress of puberty in the rats was measured by preputial separation, while spermatogenesis was assayed by (1) measuring the sperm count in testes and epididymis and (2) examining the morphology and morphometry of seminiferous epithelium using stereological analysis. In addition, testosterone and estradiol levels were assayed by radioimmunoassay. The weight of the animals at PND90 did not change markedly, but growth was less in the group treated with AgNP at 50 μg/kg from PND34 to PND53. AgNP exposure produced a delay in puberty in both treated groups. Decreased sperm reserves in the epididymis and diminished sperm transit time were observed at PND53, while a reduction in sperm production occurred at PND90. The morphology of the seminiferous epithelium was markedly altered. Data demonstrated that prepubertal exposure to AgNP altered reproductive development in prepubertal male Wistar rats, as evidenced by impairment in spermatogenesis and a lower sperm count in adulthood. © 2013 Copyright Taylor and Francis Group, LLC.


Ferreira A.S.,Federal University of Paraná | Goncalves R.A.,State University of Centro Oeste | Pozo A.T.R.,Federal University of Paraná
Proceedings - 2015 Brazilian Conference on Intelligent Systems, BRACIS 2015 | Year: 2015

Hyper-heuristics are search methods that aim to solve optimization problems by selecting or generating heuristics. Selection hyper-heuristics choose from a pool of heuristics a good one to be applied at the current stage of the optimization process. The selection mechanism is the main part of a selection hyper-heuristic and have a great impact on its performance. In this paper a deterministic selection mechanism based on the concepts of the Multi-Armed Bandit (MAB) problem is proposed. The proposed approach is integrated into the HyFlex framework and is compared to twenty other hyper-heuristics using the methodology adapted by the CHeSC 2011 Challenge. The results obtained were good and comparable to those attained by the best hyper-heuristics. Therefore, it is possible to affirm that the use of a MAB mechanism as a selection method in a hyper-heuristic is a promising approach. © 2015 IEEE.


Mathias F.T.,State University of Centro Oeste | Romano R.M.,Federal University of São Paulo | Kizys M.M.L.,Federal University of São Paulo | Kasamatsu T.,Federal University of São Paulo | And 5 more authors.
Nanotoxicology | Year: 2013

As silver nanoparticles (AgNPs) have antimicrobial properties and potentiate the activity of some antibiotics, they are broadly used in both medical and nonmedical applications. In this study, prepubertal male Wistar rats were orally treated with 15 or 30 μg/kg/day AgNPs from postnatal day 23 (PND23) to PND58 and sacrificed at PND102. The acrosome integrity, plasma membrane integrity, mitochondrial activity and morphological alterations of the sperm were analyzed. Sexual partner preference, sexual behavior and the serum concentrations of FSH, LH, testosterone and estradiol were also recorded. The results were evaluated following the appropriate statistical analyses, and differences among the groups were considered significant when p < 0.05. AgNPs reduced the acrosome and plasma membrane integrities, reduced the mitochondrial activity and increased the abnormalities of the sperm in both treatment groups. AgNP exposure also delayed the onset of puberty, although no changes in body growth were observed in either treatment group. The animals did not show changes in sexual behavior or serum hormone concentrations. This study shows for the first time that prepubertal exposure to AgNPs causes alterations in adult sperm parameters. Importantly, the sperm appeared to be more sensitive to the toxic effects of AgNPs and demonstrated adverse effects following exposure to lower doses. Consequently, the effects of AgNPs on sperm should be considered in order to establish safety limits for the use of these particles. © 2014 Informa UK Ltd. All rights reserved.


Wisniewski P.,State University of Centro Oeste | Romano R.M.,State University of Centro Oeste | Kizys M.M.L.,Federal University of São Paulo | Oliveira K.C.,Federal University of São Paulo | And 5 more authors.
Toxicology | Year: 2015

Reproductive physiology involves complex biological processes that can be disrupted by exposure to environmental contaminants. The effects of bisphenol A (BPA) on spermatogenesis and sperm quality is still unclear. The objective of this study was to investigate the reproductive toxicity of BPA at dosages considered to be safe (5 or 25. mg BPA/kg/day). We assessed multiple sperm parameters, the relative expression of genes involved in the central regulation of the hypothalamic-pituitary-testicular axis, and the serum concentrations of testosterone, estradiol, LH and FSH. BPA exposure reduced sperm production, reserves and transit time. Significant damage to the acrosomes and the plasma membrane with reduced mitochondrial activity and increased levels of defective spermatozoa may have compromised sperm function and caused faster movement through the epididymis. BPA exposure reduced the serum concentrations of testosterone, LH and FSH and increased the concentration of estradiol. The relative gene expression revealed an increase in gonadotropin releasing hormone receptor (. Gnrhr), luteinizing hormone beta (. Lhb), follicle stimulating hormone beta (. Fshb), estrogen receptor beta (. Esr2) and androgen receptor (. Ar) transcripts in the pituitary and a reduction in estrogen receptor alpha (. Esr1) transcripts in the hypothalamus. In this study, we demonstrated for the first time that adult male exposure to BPA caused a reduction in sperm production and specific functional parameters. The corresponding pattern of gene expression is indicative of an attempt by the pituitary to reestablish normal levels of LH, FSH and testosterone serum concentrations. In conclusion, these data suggest that at dosages previously considered nontoxic to reproductive function, BPA compromises the spermatozoa and disrupts the hypothalamic-pituitary-gonadal axis, causing a state of hypogonadotropic hypogonadism. © 2015 Elsevier Ireland Ltd.


Romano R.M.,University of Sao Paulo | Romano M.A.,State University of Centro Oeste | Bernardi M.M.,University of Sao Paulo | Furtado P.V.,University of Sao Paulo | Oliveira C.A.,University of Sao Paulo
Archives of Toxicology | Year: 2010

Glyphosate is a herbicide widely used to kill weeds both in agricultural and non-agricultural landscapes. Its reproductive toxicity is related to the inhibition of a StAR protein and an aromatase enzyme, which causes an in vitro reduction in testosterone and estradiol synthesis. Studies in vivo about this herbicide effects in prepubertal Wistar rats reproductive development were not performed at this moment. Evaluations included the progression of puberty, body development, the hormonal production of testosterone, estradiol and corticosterone, and the morphology of the testis. Results showed that the herbicide (1) significantly changed the progression of puberty in a dose-dependent manner; (2) reduced the testosterone production, in semineferous tubules' morphology, decreased significantly the epithelium height (P < 0.001; control = 85.8 ± 2.8 μm; 5 mg/kg = 71.9 ± 5.3 μm; 50 mg/kg = 69.1 ± 1.7 μm; 250 mg/kg = 65.2 ± 1.3 μm) and increased the luminal diameter (P < 0.01; control = 94.0 ± 5.7 μm; 5 mg/kg = 116.6 ± 6.6 μm; 50 mg/kg = 114.3 ± 3.1 μm; 250 mg/kg = 130.3 ± 4.8 μm); (4) no difference in tubular diameter was observed; and (5) relative to the controls, no differences in serum corticosterone or estradiol levels were detected, but the concentrations of testosterone serum were lower in all treated groups (P < 0.001; control = 154.5 ± 12.9 ng/dL; 5 mg/kg = 108.6 ± 19.6 ng/dL; 50 mg/dL = 84.5 ± 12.2 ng/dL; 250 mg/kg = 76.9 ± 14.2 ng/dL). These results suggest that commercial formulation of glyphosate is a potent endocrine disruptor in vivo, causing disturbances in the reproductive development of rats when the exposure was performed during the puberty period. © 2009 Springer-Verlag.


PubMed | State University of Centro Oeste
Type: | Journal: ISRN toxicology | Year: 2013

S-metolachlor is a chloroacetanilide herbicide widely used in the agriculture to control weeds and was demonstrated that it increases the activity of the aromatase enzyme in cell cultures, which may culminate as endocrine disruption action in vivo. To investigate this hypothesis, prepubertal Wistar male rats were exposed to metolachlor (5 or 50mg/kg/day, NOEL for reproductive toxicity: 23.5-26.0mg/kg/day) from PND23 (postnatal day) to PND53. During this period, the growth of the animals and the age and weight at puberty were recorded. In PND53, tissues were collected and the analysis of LH, FSH, testosterone, dihydrotestosterone (DHT), estradiol serum concentrations, morphometric evaluation of the seminiferous epithelium, and weight of the testes and the seminal vesicle (undrained and drained) was performed (Statistical difference: P < 0.05). Metolachlor caused an increase in serum concentrations of testosterone, estradiol, and FSH and a reduction in DHT but did not alter the LH. There were also observed a higher amount of fluid in the seminal vesicles, precocious puberty, and changes in morphology of the seminiferous epithelium of treated animals. We demonstrated in this paper that prepubertal exposure to S-metolachlor caused changes in reproductive endocrinology of male rats.


PubMed | State University of Centro Oeste
Type: Journal Article | Journal: Nanotoxicology | Year: 2015

As silver nanoparticles (AgNPs) have antimicrobial properties and potentiate the activity of some antibiotics, they are broadly used in both medical and nonmedical applications. In this study, prepubertal male Wistar rats were orally treated with 15 or 30g/kg/day AgNPs from postnatal day 23 (PND23) to PND58 and sacrificed at PND102. The acrosome integrity, plasma membrane integrity, mitochondrial activity and morphological alterations of the sperm were analyzed. Sexual partner preference, sexual behavior and the serum concentrations of FSH, LH, testosterone and estradiol were also recorded. The results were evaluated following the appropriate statistical analyses, and differences among the groups were considered significant when p<0.05. AgNPs reduced the acrosome and plasma membrane integrities, reduced the mitochondrial activity and increased the abnormalities of the sperm in both treatment groups. AgNP exposure also delayed the onset of puberty, although no changes in body growth were observed in either treatment group. The animals did not show changes in sexual behavior or serum hormone concentrations. This study shows for the first time that prepubertal exposure to AgNPs causes alterations in adult sperm parameters. Importantly, the sperm appeared to be more sensitive to the toxic effects of AgNPs and demonstrated adverse effects following exposure to lower doses. Consequently, the effects of AgNPs on sperm should be considered in order to establish safety limits for the use of these particles.


PubMed | Federal University of Paraná, Institute Pesquisa Pele Pequeno Principe and State University of Centro Oeste
Type: | Journal: International journal of biological macromolecules | Year: 2016

In order to obtain polysaccharides from green and black teas (Camellia sinensis), commercial leaves were submitted to infusion and then to alkaline extraction. The extracts were fractionated by freeze-thawing process, giving insoluble and soluble fractions. Complex arabinogalactan protein from the soluble fractions of both teas (GTPS and BTPS) were determined by methylation analysis and (1)H/(13)C-HSQC spectroscopy, showing a main chain of (13)--Galp, substituted at O-6 by (16)-linked -Galp with side chains of -Araf and terminal units of -Araf, -Fucp and -Rhap. A highly branched heteroxylan from the insoluble fractions (GTPI and BTPI) showed in methylation analysis and (1)H/(13)C-HSQC spectroscopy the main chain of (14)--Xylp, substituted in O-3 by -Araf, -Galp and -Glcp units. Evaluating their gastroprotective activity, the fractions containing the soluble heteropolysaccharides from green (GTPS) and black teas (BTPS) reduced the gastric lesions induced by ethanol. Furthermore, the fraction of insoluble heteropolysaccharides of green (GTPI) and black (BTPI) teas also protected the gastric mucosa. In addition, the maintenance of gastric mucus and reduced glutathione (GSH) levels was involved in the polysaccharides gastroprotection.

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