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1.
Braz J Biol ; 83: e278007, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126483

RESUMO

Low density sugarcane plantation (LDSP) has been implemented by some sugarcane producers in Brazil, aiming to save seeds and operational costs. The study was carried out in the municipality of Areia, Paraíba, Brazil. Five planting densities were used, varying from 5 to 25 m-2 of buds arranged in randomized blocks, with four replications. Data were measured annually over three cultivation cycles (2017 to 2020), during which the field was fertilized with NPK and the harvests were carried out manually without prior burning. The lower planting density presents higher productivity only in the cane plant (101.03 t ha-1) due to the higher plant height (2.37 m) and the higher number of stalks (11 stalks m-2), suggesting that these variables are due to the greater availability of light, water and photosynthate. However, there is a drastic reduction in sugarcane yield for this lower population in the 2nd ratoon by up to 65.62%, which is correlated with number of stalks per meter. We demonstrate the agronomic viability of LDSP in the population of 10 buds m-2 in relation to conventional planting of sugarcane until the 2nd ratoon. Data are important for future studies to present additional considerations for other production factors, such as the effects of mechanized harvesting and the management of nutrients and water, assessing the sustainability of this large-scale planting system.


Assuntos
Saccharum , Agricultura , Sementes , Água , Brasil
2.
Mater Today Bio ; 3: 100026, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32159152

RESUMO

Unlike the central nervous system, peripheral nerves can regenerate after injury. However, depending on the size of the lesion, the endogenous regenerative potential is not enough to replace the lost nerve tissue. Many strategies have been used to generate biomaterials capable of restoring nerve functions. Here, we set out to investigate whether adsorbing the extracellular matrix protein, laminin (LM), to poly-ℇ-caprolactone (PCL) filaments would enhance functional nerve regeneration. Initial in vitro studies showed that explants of dorsal root ganglia (DRGs) of P1 neonate mice exhibited stronger neuritogenesis on a substrate of LM that had been previously polymerized (polylaminin [polyLM]) than on ordinary LM. On the other hand, when silicone tubes filled with PCL filaments were used to bridge a 10-mm sciatic nerve gap in rats, only filaments coated with LM improved tissue replacement beyond that obtained with empty tubes. Motor function recovery correlated with tissue replacement as only LM-coated filaments consistently improved motor skills. Finally, analysis of the lateral gastrocnemius muscle revealed that the LM group presented twice the amount of α-bungarotixin-labeled motor plates. In conclusion, although polyLM was more effective in stimulating growth of sensory fibers out of DRGs in vitro, LM adsorbed to PCL filaments exhibited the best regenerative properties in inducing functional motor recovery after peripheral injury in vivo.

3.
Life Sci ; 169: 37-42, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27984075

RESUMO

INTRODUCTION: Acute kidney injury is a serious public health problem, especially in intensive care units, where patients may require dialysis support, resulting in 50% mortality. AIM: To evaluate the effects of moderate aerobic exercise on the recovery phase of acute kidney injury induced by gentamicin in rats. MAIN METHODS: Male adult Wistar rats were allocated into 4 groups: W10+R30, G10+R30, W10+EX30 and G10+EX30; W10 received water (gentamicin vehicle) and G10 received gentamicin for 10days; R30 remained resting and EX30 made exercise for 30days after gentamicin suspension. Training was performed on treadmill. Blood, 24h urine and kidneys were collected for renal function and oxidative stress, antioxidant, TGF-ß and histological analysis. KEY FINDINGS: Gentamicin treatment caused decreased renal function significant oxidative stress, reduced urinary nitric oxide and increased TGF-ß. G10+R30 presented partial recovery of metabolic data, renal function and lipoperoxidation levels, although they were still altered compared to W10+R30. Besides, we observed the presence of lymphomononuclear infiltrate in the kidneys of G10+R30. G10+EX30 vs G10+R30 showed additional improvement of all the mentioned parameters, showing at histology, regeneration of the tubule epithelium. SIGNIFICANCE: Our data suggest that moderate exercises could help in the recovery of metabolic parameters, renal function and structure on gentamicin-induced AKI, perhaps due to restoration of redox balance. This could protect the kidneys from further insults like challenges with nephrotoxic drugs or the aging per se.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/terapia , Antibacterianos , Terapia por Exercício/métodos , Gentamicinas , Rim/fisiopatologia , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/fisiopatologia , Animais , Rim/efeitos dos fármacos , Rim/metabolismo , Testes de Função Renal , Masculino , Estresse Oxidativo/efeitos dos fármacos , Condicionamento Físico Animal , Ratos Wistar
4.
Environ Sci Pollut Res Int ; 22(24): 20060-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26300358

RESUMO

This study was designed to assess the presence of human adenovirus (HAdV), rotavirus-A (RVA), hepatitis A virus (HAV), and porcine circovirus-2 (PCV2) in groundwater from deep wells, and recreational and network waters. The water samples were collected and concentrated and the virus genomes were assessed and quantified by quantitative PCR (qPCR). Infectious HAdV was evaluated in groundwater and network water samples by integrated cell culture using transcribed messenger RNA (mRNA) (ICC-RT-qPCR). In recreational water samples, HAdV was detected in 100 % (6/6), HAV in 66.6 % (4/6), and RVA in 66.6 % (4/6). In network water, HAdV was detected in 100 % (6/6) of the samples (these 83 % contained infectious HAdV), although HAV and RVA were not detected and PCV2 was not evaluated. In groundwater from deep wells, during rainy period, HAdV and RVA were detected in 80 % (4/5) of the samples, and HAV and PCV2 were not detected; however, during dry period, HAdV and RVA were detected in 60 % (3/5), HAV in only one sample, and PCV2 in 60 % (4/5). In groundwater, all samples contained infectious HAdV. PCV2 presence in groundwater is indicative of contamination caused by swine manure in Concórdia, Santa Catarina, Brazil. The disinfection of human and animal wastes is urgent, since they can contaminate surface and groundwater, being a potential threat for public and animal health.


Assuntos
Adenovírus Humanos/isolamento & purificação , Circovirus/isolamento & purificação , Água Subterrânea/virologia , Rotavirus/isolamento & purificação , Microbiologia da Água , Adenovírus Humanos/genética , Adenovírus Humanos/patogenicidade , Animais , Brasil , Linhagem Celular Tumoral , Circovirus/genética , Circovirus/patogenicidade , Genes Virais , Humanos , Esterco/virologia , Parques Recreativos , Reação em Cadeia da Polimerase em Tempo Real , Rotavirus/genética , Rotavirus/patogenicidade , Estações do Ano , Suínos , Qualidade da Água , Poços de Água
5.
Phys Chem Chem Phys ; 16(25): 12793-801, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24837441

RESUMO

A study of the OH + SO → H + SO2 reaction using a quasi-classical trajectory method is presented with the aim of investigating the role of the ro-vibrational energy of the reactants in the reactivity. The calculations were carried out using a previously reported global potential energy surface for HSO2((2)A). Different initial conditions with one and both reactants ro-vibrationally excited were studied. The reactive cross sections, for each studied combination, are calculated and then fitted to a capture-like model combined with a factor accounting for the recrossing effects. The Vibrational Energy Quantum Mechanical Threshold of the Complex method was used to correct for the zero-point vibrational energy leakage of the classical calculations. State specific and averaged rate constants are reported. The reactivity is affected when ro-vibrational energy of either of the reactants is changed. The present calculations provide a theoretical support for the experimental rate constant for temperatures below 550 K, but fail to account for the significant fall in the observed rate constant upon increasing the temperature above this value.

6.
Int J Sports Med ; 34(9): 806-13, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23459854

RESUMO

The purpose of this study was to investigate the effect of resistance training on resting blood pressure and heart rate variability in elderly postmenopausal women. 29 untrained, non-hypertensive elderly women were randomly assigned to 2 groups: an intervention group (n=15, 65.5±5.0 years, 57.3±6.5 kg, 156.7±5.1 cm) that underwent a supervised resistance training program (8 exercises, 2 sets, 10-15 repetitions, 3 times/week) or a control group (n=14, 66.2±4.1 years, 61.1±11.7 kg, 157.5±7.1 cm) that participated in a supervised stretching program (25-30 min/session, 2 times/week). Resting auscultatory blood pressure, heart rate variability, evaluated from short recordings in a seated position, and maximal dynamic strength (1-RM test) were measured at baseline and after 12 weeks. A group x time ANOVA revealed that muscular strength increased significantly in the resistance training group (+ 10.2% for bench press and +12.7% for leg extension, P<0.05). Systolic blood pressure was reduced significantly in the resistance training group from pre- to post-intervention period (- 5 mmHg; P<0.05), while no significant effect was noted for diastolic blood pressure and heart rate variability indexes (P>0.05). None of these variables changed in the control group throughout the study. In conclusion, a supervised resistance training program improved muscular strength and reduced systolic blood pressure without affecting diastolic blood pressure and heart rate variability in elderly postmenopausal women.


Assuntos
Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Pós-Menopausa , Treinamento Resistido/métodos , Idoso , Análise de Variância , Feminino , Humanos , Pessoa de Meia-Idade , Força Muscular/fisiologia
7.
Water Sci Technol ; 66(12): 2682-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23109586

RESUMO

The present study evaluated the contamination of a surface water lagoon (Peri Lagoon) in Florianópolis, Santa Catarina, Brazil, by human adenovirus (HAdV), polyomavirus JC (JCPyV), hepatitis A virus (HAV) and rotavirus species A (RVA). Efforts were driven to determine the correlation between viral presence and the physicochemical parameters of the lagoon and measure the distribution of these viruses throughout the year (June 2010 to May 2011). A total of 48 samples were collected, concentrated and analyzed by qPCR (quantitative polymerase chain reaction). Approximately 96% of the samples were positive for HAdV (46/48), 65% were positive for RVA (31/48), 21% were positive for JCPyV (10/48) and 12% were positive for HAV (6/48). The presence of JCPyV was positively correlated with that of NO(2)(-)N, and also there was a positive correlation between the presence of each one of the viruses (HAdV, HAV and RVA) in winter. Samples from water dedicated for human consumption and recreation tested positive for HAdV by qPCR. These samples were also subjected to viral integrity and viability assays: 83% (10/12) contained intact viral particles and 66% (8/12) contained infectious particles. Our results demonstrate the release of human waste into water sources, justifying the urgent need to add viral parameters to water quality surveillance.


Assuntos
Fenômenos Químicos , Monitoramento Ambiental , Vírus/isolamento & purificação , Microbiologia da Água , Poluição da Água/análise , Abastecimento de Água , Adenovírus Humanos/isolamento & purificação , Brasil , Desoxirribonucleases/metabolismo , Geografia , Humanos , Reação em Cadeia da Polimerase , Propriedades de Superfície
8.
Mar Pollut Bull ; 64(1): 40-48, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22104718

RESUMO

The aim of this study was to assess the impact of sewage discharge on coastal waters by evaluating the influence of physicochemical parameters on the presence of enteric microorganisms in seawater samples collected from 11 beaches in Florianopolis, Santa Catarina, Brazil, over a one-year period (August 2009 to July 2010). Samples were assessed for the presence of human adenoviruses (HAdV), polyomavirus (JCPyV), hepatitis A virus (HAV), and noroviruses (HuNoV GI and GII). Escherichia coli and physicochemical parameters (salinity, temperature, pH and dissolved oxygen) were also evaluated. From the 132 samples analyzed, 55% were positive for HAdV, 51.5% for HAV, 7.5% for HuNoV GI, 4.5% for HuNoV GII, and 3% for JCPyV. E. coli levels ranged from 8 to 1325 CFU/100mL at all sites. The overall results highlight the problem of sewage discharge into coastal waters and confirm that there is no correlation between viral presence and bacterial contamination.


Assuntos
Monitoramento Ambiental/métodos , Água do Mar/química , Poluentes da Água/análise , Adenovírus Humanos/isolamento & purificação , Brasil , DNA Viral/análise , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/isolamento & purificação , Vírus da Hepatite A/isolamento & purificação , Norovirus/isolamento & purificação , Água do Mar/microbiologia , Água do Mar/virologia , Esgotos/análise , Esgotos/estatística & dados numéricos , Poluição da Água/análise , Poluição da Água/estatística & dados numéricos
9.
J Phys Chem A ; 110(33): 10018-24, 2006 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-16913675

RESUMO

Positive and negatively charged ammonia clusters produced by the impact of (252)Cf fission fragments (FF) on an NH(3) ice target have been examined theoretical and experimentally. The ammonia clusters generated by (252)Cf FF show an exponential dependence of the cluster population on its mass, and the desorption yields for the positive (NH(3))(n)NH(4)(+) clusters are 1 order of magnitude higher than those for the negative (NH(3))(n)NH(2)(-) clusters. The experimental population analysis of (NH(3))(n)NH(4)(+) (n = 0-18) and (NH(3))(n)NH(2)(-) (n = 0-8) cluster series show a special stability at n = 4 and 16 and n = 2, 4, and 6, respectively. DFT/B3LYP calculations of the (NH(3))(0)(-)(8)NH(4)(+) clusters show that the structures of the more stable conformers follow a clear pattern: each additional NH(3) group makes a new hydrogen bond with one of the hydrogen atoms of an NH(3) unit already bound to the NH(4)(+) core. For the (NH(3))(0)(-)(8)NH(2)(-) clusters, the DFT/B3LYP calculations show that, within the calculation error, the more stable conformers follow a clear pattern for n = 1-6: each additional NH(3) group makes a new hydrogen bond to the NH(2)(-) core. For n = 7 and 8, the additional NH(3) groups bind to other NH(3) groups, probably because of the saturation of the NH(2)(-) core. Similar results were obtained at the MP2 level of calculation. A stability analysis was performed using the commonly defined stability function E(n)(-)(1) + E(n)(+1) - 2E(n), where E is the total energy of the cluster, including the zero point correction energy (E = E(t) + ZPE). The trend on the relative stability of the clusters presents an excellent agreement with the distribution of experimental cluster abundances. Moreover, the stability analysis predicts that the (NH(3))(4)NH(4)(+) and the even negative clusters [(NH(3))(n)NH(2)(-), n = 2, 4, and 6] should be the most stable ones, in perfect agreement with the experimental results.

10.
Bioresour Technol ; 97(12): 1387-91, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16226027

RESUMO

Turnera ulmifolia L. is used in Brazilian folk medicine as an anti-inflammatory. Since this activity may be correlated with the presence of antioxidant compounds, a leaf extract was evaluated for its radical scavenging capacity (RSC). The in vitro RSC of a 50% hydroethanolic (HE) extract was evaluated by beta-carotene/linoleic acid coupled oxidation system for the inhibition of oxidation and the lipid peroxidation inhibition in rat brain homogenates, using thiobarbituric acid reactive substances (TBARS) and chemiluminescence (CL). Results indicated, through peroxidation suppression, that this extract exhibited greater antioxidative activity (77.4% +/- 10%) than alpha-tocopherol (58.4% +/- 3.7%). TBARS and CL inhibition was concentration-dependent and Q(1/2) values were 8.2 and 6.0 microg/mL for TBARS and CL, respectively. For alpha-tocopherol these values were 7.1 microg/mL (TBARS) and 9.8 microg/mL (CL). Phenolic compounds may be responsible for this antioxidant capacity.


Assuntos
Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Turnera/metabolismo , Animais , Antioxidantes/metabolismo , Biotecnologia/métodos , Encéfalo/metabolismo , Desenho de Fármacos , Radicais Livres , Peroxidação de Lipídeos , Folhas de Planta , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico , beta Caroteno/metabolismo
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