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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.
Braz J Med Biol Res ; 56: e12777, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37493773

RESUMO

To evaluate the risks of hair dye exposure, we investigated cellular and molecular effects of Arianor Ebony dye, which is a mixture of azo and anthraquinone dyes, used in the composition of the black color. Cytotoxicity, genotoxicity, and gene expression of relevant molecules of apoptotic and oxidative stress mechanisms were investigated in HepG2 cells exposed to Arianor Ebony. Results showed that the dye did not induce cytotoxicity to exposed cells at a concentration up to 50 µg/mL compared to the negative control. However, genotoxic assays indicated that the dye was able to damage the genetic material at a concentration of 25 µg/mL, with induction factor values of exposed cells two- to five-fold higher than those recorded for the negative control. Moreover, the lowest observed effect concentration was 12.5 µg/mL. For gene expression, relevant changes were observed in cytochrome c and caspase 9, which decreased in cells incubated with the dye in a dose-dependent manner when compared with the negative control. In parallel, the expression of genes for antioxidant enzymes was increased in exposed cells, suggesting the presence of metabolic routes that protect cells against the toxic effect of the dye, avoiding exacerbated cellular death. Results suggested that the dye disrupted cellular homeostasis through mitochondrial dysfunction, which may be hazardous to human health. Thus, further investigations are necessary to deeply understand the mechanisms of action of the dye, considering its toxic potential found in our ex vivo assays.


Assuntos
Tinturas para Cabelo , Humanos , Tinturas para Cabelo/toxicidade , Células Hep G2
3.
Braz J Biol ; 83: e273414, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283339

RESUMO

Sugarcane cultivation stands out in Brazilian agribusiness, covering more than eight million hectares for the production of sugar, ethanol, and by-products. Fertilization is one of the limiting factors in sugarcane yield, for which filter cake is a viable solution to meet plant nutritional needs. This study aimed to assess the effect of enriched filter cake on gas exchange and yield in RB041443 sugarcane, cultivated in soils of the coastal tablelands of Paraíba, Brazil. The experiment was conducted in the Monte Alegre S/A sugarcane mill, in the municipality of Mamanguape, using a randomized blocks experimental design, with 12 treatments (T1- cake, T2- cake + MAP, T3- cake + gypsum, T4 - cake + phosphate, T5- cake + bagasse, T6- cake + MAP + gypsum, T7- cake + MAP + phosphate, T8- cake + MAP + bagasse, T9- cake + gypsum + phosphate, T10- cake + gypsum + bagasse, T11- cake + phosphate + bagasse, and T12- control (only MAP)), and 4 replications, totaling 48 plots. A significant effect (5% probability) was also observed for the variables number of leaves and tons of stem per hectare (TSH). T1- cake, T4- cake + phosphate, T6- cake + MAP + gypsum and T10- cake + gypsum + bagasse, had the best results for TSH, with yields greater than 140 t ha-1. Regarding stomatal conductance, the highest values were obtained in T6 and T8, which, together with T11, had the highest gs values. Concerning the internal carbon concentration, T1, T2, T6, and T8 stood out. T6 also had a significant effect on transpiration. From this study, it was concluded that the use of enriched filter cake as a base fertilizer in sugarcane culture contributes to increasing the yield of the RB041443 variety, generating positive responses for plant gas exchange, being T1 and T10 indicated to increase the production in the sugar-energy sector.


Assuntos
Saccharum , Sulfato de Cálcio , Grão Comestível , Fosfatos , Açúcares , Tireotropina
4.
Braz. j. med. biol. res ; 56: e12777, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1447683

RESUMO

To evaluate the risks of hair dye exposure, we investigated cellular and molecular effects of Arianor Ebony dye, which is a mixture of azo and anthraquinone dyes, used in the composition of the black color. Cytotoxicity, genotoxicity, and gene expression of relevant molecules of apoptotic and oxidative stress mechanisms were investigated in HepG2 cells exposed to Arianor Ebony. Results showed that the dye did not induce cytotoxicity to exposed cells at a concentration up to 50 µg/mL compared to the negative control. However, genotoxic assays indicated that the dye was able to damage the genetic material at a concentration of 25 µg/mL, with induction factor values of exposed cells two- to five-fold higher than those recorded for the negative control. Moreover, the lowest observed effect concentration was 12.5 µg/mL. For gene expression, relevant changes were observed in cytochrome c and caspase 9, which decreased in cells incubated with the dye in a dose-dependent manner when compared with the negative control. In parallel, the expression of genes for antioxidant enzymes was increased in exposed cells, suggesting the presence of metabolic routes that protect cells against the toxic effect of the dye, avoiding exacerbated cellular death. Results suggested that the dye disrupted cellular homeostasis through mitochondrial dysfunction, which may be hazardous to human health. Thus, further investigations are necessary to deeply understand the mechanisms of action of the dye, considering its toxic potential found in our ex vivo assays.

5.
West Afr J Med ; 30(5): 373-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22752827

RESUMO

BACKGROUND: Many studies have found an association between sodium intake and blood pressure. Salt taste threshold is thought to be another marker of sodium intake. OBJECTIVE: This study sought to assess two markers of sodium intake, 24-hour-urinary sodium and salt-taste threshold. We also determined the relationship between these two markers and blood pressure. METHODS: Salt taste threshold was measured by the ability of the subjects to discern the taste of salt in graded solutions of saline. Twenty-four urinary sodium was measured by flame photometry in a 24-hour urine collection. Other plasma and urine electrolytes and creatinine were measured using standard automated chemistry methods. RESULTS: There was a significantly higher salt intake measured as 24-hour urinary sodium/mmol of creatinine in the hypertensive group, (36.6±20mmol/L/mmol creatinine) compared with the normotensive group (14.8±5.8mmol/L/mmol creatinine) p<0.001. Urinary potassium was also higher in the hypertensive subjects. When the subjects were grouped into low and high salt taste threshold, the high salt threshold group also had significantly higher 24 hour urinary sodium (30.3±5mmol/L creatinine vs the low STT urinary sodium of (19.5±14 p <.05). CONCLUSION: Sodium intake measured as 24-hour urinary sodium is increased in subjects with hypertension attesting to sodium intake as a risk factor for the development of high blood pressure. Subjects with high salt taste threshold also have increased urinary sodium excretion which may predispose them to development of hypertension.


Assuntos
Pressão Sanguínea/fisiologia , Hipertensão/epidemiologia , Sódio na Dieta/administração & dosagem , Limiar Gustativo/fisiologia , Adulto , Idoso , Pressão Sanguínea/efeitos dos fármacos , Feminino , Seguimentos , Humanos , Hipertensão/etiologia , Hipertensão/fisiopatologia , Incidência , Masculino , Pessoa de Meia-Idade , Nigéria/epidemiologia , Sódio na Dieta/efeitos adversos , Limiar Gustativo/efeitos dos fármacos , Adulto Jovem
6.
Nig Q J Hosp Med ; 18(2): 92-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19068560

RESUMO

Two methods are presented for the simultaneous determination of benzoic and salicylic acids in pharmaceutical preparations using first (1D) derivative spectrophotometry and high-performance liquid chromatography. Benzoic and salicylic acids were determined by measurement of first derivative amplitude at the zero crossing points 283 and 310 nm respectively. Methanolic solutions obeyed Beer's law in the concentration range of 20-60 and 10-30 microg/ml for benzoic and salicylic acids respectively. The HPLC method depends upon using a Vydac reversed-phase column at ambient temperature with a mobile phase consisting of 20:80 (ACN:H2O) at a flow rate 0.5 ml min(-1) Quantitation was achieved with UV detection of 230 nm at 0 min and 204 nm at 4 min based on peak area. For the two methods the regression line equations were derived with correlation coefficient better than 0.995. The two methods were successfully applied to the simultaneous determination of benzoic and salicylic acids in laboratory-prepared mixtures and in creams with good accuracy and precision. No significant differences were found between the results obtained both by the HPLC and derivative procedures.


Assuntos
Ácido Benzoico/química , Cromatografia Líquida de Alta Pressão , Preparações Farmacêuticas/química , Ácido Salicílico/química , Espectrofotometria Ultravioleta , Humanos , Análise de Regressão , Fatores de Tempo
7.
Nig Q J Hosp Med ; 18(2): 101-3, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19068562

RESUMO

BACKGROUND: In Nigeria, diarrhoeal disease is second only to malaria as a cause of death the under 5 age group. This study was aimed at assessing the benefit or otherwise of zinc supplement in acute diarrhoea. SUBJECTS AND METHODS: This was a multi-centred randomized double blind controlled study. Children with acute diarrhoea aged between 6 and 24 months were randomized into zinc supplemented and placebo groups. Plasma zinc levels were analyzed at enrollment and at the end of the study. The children were reviewed for the next three months from the time of enrollment. RESULTS: The mean plasma zinc levels at baseline and at the end of the study were 0.06 +/- 0.04 and 0.067 +/- 0.03 ppm in the zinc supplemented group and 0.11 +/- 0.02 and 0.05 +/- 0.03 ppm in the control group. The differences were not statistically significant. The zinc supplemented group had an average weight gain of 1.1 kg as against 0.73 kg (p = 0.00) for the control group in the study period. No adverse effect was reported on account of zinc supplementation. CONCLUSION: Zinc supplementation is beneficial in acute diarrhoea as observed in this study.


Assuntos
Diarreia Infantil/tratamento farmacológico , Suplementos Nutricionais , Compostos de Zinco/uso terapêutico , Doença Aguda , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Lactente , Masculino , Estado Nutricional , Aumento de Peso , Compostos de Zinco/sangue
8.
Arq. bras. med. vet. zootec ; 58(6): 1192-1198, dez. 2006. tab
Artigo em Português | LILACS | ID: lil-455067

RESUMO

Avaliaram-se o consumo e a digestibilidade aparente de dietas, contendo diferentes proporções de silagem de girassol em substituição à silagem de milho, para vacas leiteiras em lactação. Foram utilizadas cinco vacas da raça Holandesa, que produziam 25kg leite/dia, distribuídas em um delineamento em quadrado latino 5´5. Os tratamentos foram compostos por: 100 por cento de silagem de girassol e concentrado (100SG), 66 por cento de silagem de girassol mais 34 por cento de silagem de milho e concentrado (66SG), 34 por cento de silagem de girassol mais 66 por cento de silagem de milho e concentrado (34SG), 100 por cento de silagem de milho e concentrado (100SM) e 100 por cento de silagem de milho mais caroço de algodão (16,5 por cento da matéria seca) e concentrado (SM+CA). A ingestão de matéria seca (17,8kg para 100SG e 21,6kg para 100SM), a ingestão de matéria orgânica (15,5kg para 100SG e 20,2kg para 100SM), a ingestão de fibra insolúvel em detergente neutro (8,1kg para 100SG e 9,9kg para 100SM), a digestibilidade aparente da fibra insolúvel em detergente neutro (30,7 por cento para 100SG e 51,4 por cento para 100SM) e da fibra insolúvel em detergente ácido (28,4 por cento para 100SG e 49,4 por cento para 100SM) foram menores para a dieta 100SG comparada à dieta 100SM (P<0,05). A substituição parcial da silagem de milho pela silagem de girassol pode ser uma alternativa viável na alimentação de vacas leiteiras.


The intake and the apparent digestibility of dry matter, organic matter, neutral detergent fiber, acid detergent fiber and the intake of crude protein were evaluated in lactating Holstein cows fed sunflower silage (SS) in replacement of corn silage (CS) in their diets. Five ruminal cannulated cows, 60 to 82 days in milk, were arranged in a 5 x 5 latin square design. The treatments werethe following: 100 percent corn silage (100CS) and concentrate; 34 percent sunflower silage plus 66 percent corn silage (34SS) and concentrate; 66 percent sunflower silage plus 34 percent corn silage (66SS) and concentrate; 100 percent sunflower silage (100SS) and concentrate;and 100 percent corn silage plus whole cotton seed (CS-WCS) and concentrate. Dry matter (17.86kg for 100SS and 21.62kg for 100CS) and organic matter intake (17.5kg for 100SS and 20.2kg for 100CS), intake and apparent digestibility of neutral detergent fiber and acid detergent fiber were lower for 100SS compared to 100CS (P<0.05). Apparent digestibility of organic matter for treatment 100SS was the lowest (54.8 percent). Increasing levels of corn silage in the diets increased the dry matter intake, the organic matter intake and the apparent digestibility. Parcial replacement of the corn silage with sunflower silage could be a viable option for lactating cows diets.


Assuntos
Animais , Bovinos , Helianthus/efeitos adversos , Matéria Orgânica/efeitos adversos , Rúmen/fisiologia , Silagem/efeitos adversos , Zea mays/efeitos adversos
9.
J Dairy Sci ; 88(8): 3000-8, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16027214

RESUMO

Four experiments were conducted to evaluate the Petrifilm Staph Express Count plate (3M, Minneapolis, MN) for diagnosis of mastitis caused by Staphylococcus aureus. The objective of experiment 1 was to determine the sensitivity of Petrifilm compared with results of standard and augmented microbiological techniques, and the objective of experiment 2 was to compare microbiological results of composite and quarter milk samples processed using Petrifilm. Experiment 3 was conducted to determine the specificity of the Petrifilm method based on different interpretation parameters, and the objective of experiment 4 was to determine the repeatability of reading Petrifilm Staph Express plates. Results of standard microbiological techniques used for experiments 1 and 2 were compared with results of samples preprocessed using centrifugation or preincubation. The prevalence of recovery of Staph. aureus from milk samples processed using Petrifilm was significantly greater than the prevalence of milk samples processed using standard microbiological techniques. The sensitivity of isolation of Staph. aureus was 65.6, 75.0, 84.4, and 87.5% for standard, centrifugation, incubation, and Petrifilm methods, respectively. The occurrence of a distinct pink zone surrounding a colony was highly specific for Staph. aureus, and the specificity was 98.5 and 96.0% for experiments 3 and 4, respectively. The use of a weak pink zone to diagnose Staph. aureus resulted in a high rate of false-positive results. The interpretation of results of Petrifilm Staph Express was associated with the person that read the plates. Results from all 4 experiments indicate potential for the Petrifilm products as a diagnostic tool in some herd situations when Staph. aureus is the pathogen of interest. Results also indicate the need for standardization of interpretive criteria for personnel working with the products.


Assuntos
Técnicas Bacteriológicas/métodos , Leite/microbiologia , Staphylococcus aureus/isolamento & purificação , Animais , Bovinos , Feminino , Manipulação de Alimentos/métodos , Mastite Bovina/microbiologia , Mastite Bovina/prevenção & controle , Sensibilidade e Especificidade , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/prevenção & controle , Infecções Estafilocócicas/veterinária
10.
Arq. bras. med. vet. zootec ; 56(6): 750-756, dez. 2004. tab
Artigo em Português | LILACS | ID: lil-394421

RESUMO

Avaliaram-se a produção e a composição do leite de vacas alimentadas com dietas contendo diferentes proporções de silagem de girassol, em substituição à silagem de milho na dieta, e caroço de algodão como substituto parcial do concentrado. Foram utilizadas cinco vacas holandesas com 25kg leite/dia, distribuídas em um delineamento em quadrado latino 5 5. Os períodos foram de 21 dias e os tratamentos foram as dietas compostas por: 100 por cento de silagem de girassol e concentrado (100SG), 66 por cento de silagem de girassol e 34 por cento de silagem de milho e concentrado (66SG), 34 por cento de silagem de girassol mais 66 por cento de silagem de milho e concentrado (34SG), 100 por cento de silagem de milho e concentrado (100SM) e 100 por cento de silagem de milho mais caroço de algodão (16,5 por cento da matéria seca) e concentrado (16,5CA). As produções de leite, proteína e extrato seco total foram inferiores no tratamento 100SG em relação ao 100SM (P<0,05). A substituição parcial de silagem de milho por silagem de girassol não afetou as produções de leite, gordura ou proteína. A substituição parcial de concentrados por caroço de algodão não afetou as características estudadas.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Bovinos , Laticínios/análise , Leite , Silagem
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