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1.
Pesqui. vet. bras ; 38(6): 1015-1025, jun. 2018. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-955456

RESUMO

This study aimed to determine the lethal concentration and the structural and ultra-structural effects caused by the formalin exposure on juveniles of Arapaima gigas. Ninety fish (60.1± 2.5g and 20.2±0.9cm) were exposed to 0, 22, 44, 66, 88 and 110mg L-1 in order to determine the lethal concentration (LC50-96h) that was 36.4mg L-1 of formalin. Sublethal effects were evaluated using histopathological analysis on the gills and assessment of behavioral alterations and clinical signs. The LC50 of formalin for 24, 48 and 72h was 88.3, 64.7 and 56.8mg L-1 respectively. Clinical signs and behavioral changes were found: erratic swimming, lethargy, crowding on the water surface, loss of hydrodynamic equilibrium, spasms and agonistic confrontation, which were observed only at 88 and 110mg L-1. The histological alteration index (HAI) showed that 66, 88 and 100mg L-1 presented significant difference (p<0.05) in relation to unexposed fish, indicating that moderate damage to the gills of fish exposed to formalin had occurred. The mean values of alteration (MVA) for 22, 44, 66, 88 and 110mg L-1 were 1.14, 1.29, 1.51, 1.53 and 1.60 respectively, and differences in this index were only observed with 110 mgL-1 of formalin. It is therefore possible to conclude that sublethal concentrations of formalin (22.0mg L-1) did not compromise the health of juveniles of A. gigas. Finally, concentrations greater than to LC50-96h may be carefully used for short-term exposure, since the MVA for all concentrations tested only indicated localized lesions that did not compromise gills functionality of exposed fish.(AU)


O presente estudo teve como objetivo determinar a concentração letal e efeitos estruturais e ultraestruturais causados pela exposição a formalina em juvenis de Arapaima gigas. Noventa peixes (60,1±2,5g e 20,2±0,9cm) foram expostos a 0, 22, 44, 66, 88 e 110mg L-1, para determinar a concentração letal (CL50-96h) de formalina que foi 36,4mg L-1. Os efeitos subletais foram avaliados por análises histopatológicas das brânquias e avaliação das alterações comportamentais e sinais clínicos. A CL50 de formalina para 24, 48 e 72horas foi de 88,3, 64,7 e 56,8; respectivamente. Sinais clínicos e alterações comportamentais encontradas foram: natação errática, letargia, aglomeração de peixes na superfície da água, perda de equilíbrio hidrodinâmico, espasmos e confronto agonísticos, observados apenas nas concentrações de 88 e 110mg L-1. O índice de alteração histológica (IAH) mostrou que as concentrações de 66, 88 e 100mg L-1 apresentaram diferenças significativas (p<0,05) em relação aos controles, indicando a ocorrência de danos moderados nas brânquias dos peixes expostos a formalina. Os valores médios de alteração (VMA) para as concentrações 22, 44, 66, 88 e 110mg L-1 foram 1,14, 1,29, 1,51, 1,53 e 1,60; respectivamente, e as diferenças na composição desse índice foram observados apenas na exposição com 110mg L-1 de formalina. Foi possível concluir que concentrações subletais de formalina (22,0mg L-1) não comprometem a saúde de juvenis de A. gigas. Concentrações de formalina acima da CL50-96h podem ser usadas cuidadosamente para banho de curto tempo, uma vez que o VMA para todas as concentrações testadas indicou apenas lesões localizadas que não comprometem a funcionalidade das brânquias dos peixes expostos.(AU)


Assuntos
Animais , Medição da Dor/veterinária , Peixes/anatomia & histologia , Toxicidade
2.
J Clin Apher ; 33(3): 331-341, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29350425

RESUMO

BACKGROUND: Autologous peripheral blood hematopoietic stem cell (PBSC) collection efficiency (CE) is reportedly affected by the patient's blood properties; however, studies to identify factors correlated with CE have shown inconsistent results. Additionally, variables such as stem cell graft granulocyte content and patient age, sex, and underlying disease, may be associated with hematopietic stem cell (HSC) infusion-related adverse reactions. In this study, we evaluated the correlation of preleukapheresis PB granulocyte count and PBSC harvest variables with CD34+ collection yield and efficiency, and thawed HSC infusion side effect occurrence. PATIENTS AND METHODS: We evaluated data from 361 patients who had undergone autologous PBSC transplant. Large volume leukapheresis was the method for PBSC collection. Complete Blood Count and CD34+ cell enumeration were performed in the preapheresis PB and the apheresis product sample. The PBSC grafts were submitted to non-controlled rate freezing after addition of 5% DMSO plus 6% hidroxyethylstarch as a cryoprotectant solution. The cryopreserved graft was thawed in a 37°C water bath and then infused without further manipulation. RESULTS: The CD34+ yield was associated with preapheresis PB CD34+ count and immature granulocyte count. The PBSC CE was negatively correlated with preapheresis white blood cell (WBC), immature granulocyte and granulocyte count. The leukapheresis product total nucleated cell (TNC) and granulocyte content was correlated with the thawed graft infusion side effect occurrence. CONCLUSION: This study has shown that preapheresis PB WBC and granulocyte counts were associated with leukapheresis CE. Additionally, the leukapheresis product TNC and granulocyte content was correlated with thawed graft infusion side effect occurrence.


Assuntos
Contagem de Leucócitos , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Células-Tronco de Sangue Periférico/citologia , Adulto , Idoso , Antígenos CD34/sangue , Criopreservação/métodos , Feminino , Granulócitos/citologia , Células-Tronco Hematopoéticas , Humanos , Leucaférese , Masculino , Pessoa de Meia-Idade , Transplante Autólogo
3.
Food Chem ; 245: 1-6, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29287315

RESUMO

This work investigated the underlying formation of acrylamide from amino acids in frying oils during high temperatures and at different times via modeling systems. Eighteen amino acids were used in order to determine which one was more effective on acrylamide production. Significantly the highest amount of acrylamide was produced from asparagine (5987.5µg/kg) and the lowest from phenylalanine (9.25µg/kg). A constant amount of asparagine and glutamine in palm olein and soy bean oils was heated up in modelling system at different temperatures (160, 180 and 200°C) and times (1.5, 3, 4.5, 6, 7.5min). The highest amount of acrylamide was found at 200°C for 7.5min (9317 and 8511µg/kg) and lowest at 160°C for 1.5min (156 and 254µg/kg) in both frying oils and both amino acids. Direct correlations have been found between time (R2=0.884), temperature (R2=0.951) and amount of acrylamide formation, both at p<0.05.


Assuntos
Acrilamida/química , Aminoácidos/química , Culinária/métodos , Óleo de Palmeira/química , Óleo de Soja/química , Asparagina/química , Glutamina/química , Temperatura
4.
Food Chem ; 212: 244-9, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27374529

RESUMO

The method of liquid chromatographic tandem mass spectrometry was utilized and modified to confirm and quantify acrylamide in heating cooking oil and animal fat. Heating asparagine with various cooking oils and animal fat at 180°C produced varying amounts of acrylamide. The acrylamide in the different cooking oils and animal fat using a constant amount of asparagine was measured. Cooking oils were also examined for peroxide, anisidine and iodine values (or oxidation values). A direct correlation was observed between oxidation values and acrylamide formation in different cooking oils. Significantly less acrylamide was produced in saturated animal fat than in unsaturated cooking oil, with 366ng/g in lard and 211ng/g in ghee versus 2447ng/g in soy oil, followed by palm olein with 1442ng/g.


Assuntos
Acrilamida/análise , Culinária/métodos , Gorduras na Dieta , Temperatura Alta , Óleos de Plantas/química , Óleo de Soja/química , Animais , Asparagina , Cromatografia Líquida , Ácidos Graxos/análise , Espectrometria de Massas em Tandem
5.
Food Chem ; 145: 514-21, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24128508

RESUMO

The aim of the study was to determine the effect of different types of sugar on the formation of heterocyclic amines (HCA) in marinated grilled chicken. Chicken breast samples were marinated with table sugar, brown sugar, and honey for 24h at 4 °C. The internal temperature, weight loss, free amino acids, sugars, and HCA were determined. The concentrations of all types of HCA (except IQx) in samples that were marinated with table sugar were significantly higher (p<0.006) than brown sugar; whereas those were marinated with honey had the lowest HCA concentrations. A substantial reduction in the concentration of MeIQ, PhIP, DiMeIQx, IQ, IQx, and norharman was achieved in chicken marinated with honey. A correlation study indicated that adding honey into the recipe retarded the formation of most HCA (MeIQ, DiMeIQx, IQ, IQx, norharman, and harman), whereas table sugars enhanced the formation of all HCA except norharman, harman, and AαC.


Assuntos
Aminas/química , Frutose/química , Glucose/química , Imidazóis/química , Carne/análise , Sacarose/química , Animais , Galinhas , Culinária , Manipulação de Alimentos/métodos , Mel
6.
J Food Sci ; 79(1): T115-21, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24344977

RESUMO

The objective of this study was to evaluate the precursors of acrylamide formation in sweet potato (SP) (Ipomoea batatas L. Lam) chips and to determine the effect of different types of vegetable oils (VOs), that is, palm olein, coconut oil, canola oil, and soya bean oil, on acrylamide formation. The reducing sugars and amino acids in the SP slices were analyzed, and the acrylamide concentrations of SP chips were measured. SP chips that were fried in a lower degree of unsaturation oils contained a lower acrylamide concentration (1443 µg/kg), whereas those fried with higher degree of unsaturated oils contained a higher acrylamide concentration (2019 µg/kg). SP roots were found to contain acrylamide precursors, that is, 4.17 mg/g glucose and 5.05 mg/g fructose, and 1.63 mg/g free asparagine. The type of VO and condition used for frying, significantly influenced acrylamide formation. This study clearly indicates that the contribution of lipids in the formation of acrylamide should not be neglected.


Assuntos
Acrilamida/análise , Culinária/métodos , Temperatura Alta , Ipomoea batatas/química , Óleos de Plantas/análise , Asparagina/análise , Cor , Frutose/análise , Glucose/análise
7.
J Food Prot ; 76(3): 462-72, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23462084

RESUMO

The objective of this study was to obtain insight into the effect of frying instructions on food handlers' control decisions in restaurants and to investigate the impact of control decisions on the variation and concentration of acrylamide in French fries. The concentrations of acrylamide and reducing sugars were analyzed, the frying temperature and time were measured, and thawing practices were observed. The results obtained before and after instructions were provided to the food handlers were compared for restaurants as a group and for each restaurant. Frying instructions supported food handlers' decisions to start frying when the oil temperature reached 175°C; all handlers started frying at the correct temperature. However, the effect of the instructions on the food handlers' decisions for frying time differed; most handlers increased the frying time beyond 240 s to achieve crispier French fries with a final color dictated by their preference. Providing instructions did not result in a significant difference in the mean concentration of acrylamide in French fries for the restaurants as a group. However, data analyzed for each restaurant revealed that when food handlers properly followed the instructions, the mean concentration of acrylamide was significantly lower (169 µg/kg) than that before instructions were provided (1,517 µg/kg). When food handlers did not complying with the frying instructions, mean acrylamide concentrations were even higher than those before instructions were provided. Two different strategies were developed to overcome the noncompliant behavior of food handlers: establishing requirements for the features of commercial fryers and strict monitoring of compliance with instructions.


Assuntos
Acrilamida/química , Culinária/métodos , Contaminação de Alimentos/análise , Solanum tuberosum/química , Acrilamida/análise , Carboidratos/química , Contaminação de Alimentos/prevenção & controle , Manipulação de Alimentos/métodos , Inocuidade dos Alimentos , Temperatura Alta , Humanos , Restaurantes , Fatores de Tempo
8.
Food Chem ; 135(3): 2012-20, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22953952

RESUMO

The objective of this study was to obtain insight into the actual effectiveness of lowering reducing sugars concentration in par-fried potato strips on the concentration and variation of acrylamide in French fries prepared in real-life situations in food service establishments. Acrylamide, frying time, frying temperature, and reducing sugars were measured and characteristics of fryers were recorded. Data showed that the use of par-fried potato strips with lower concentrations of reducing sugars than the commonly used potato strips was an effective measure to reduce acrylamide concentrations in French fries prepared under standardised frying conditions. However, there was still large variation in the acrylamide concentrations in French fries, although the variation in reducing sugars concentrations in low and normal types of par-fried potato strips was very small and the frying conditions were similar. Factors that could affect the temperature-time profile of frying oil were discussed, such as setting a lower frying temperature at the end than at the start of frying, product/oil ratio and thawing practice. These need to be controlled in daily practice to reduce variation in acrylamide.


Assuntos
Acrilamida/química , Carboidratos/química , Culinária/métodos , Serviços de Alimentação/normas , Solanum tuberosum/química , Inocuidade dos Alimentos , Oxirredução , Tubérculos/química
9.
Food Chem ; 132(1): 134-43, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26434272

RESUMO

Acrylamide is a probable human carcinogen, and its presence in a range of fried and oven-cooked foods has raised considerable health concern world-wide. Dietary intake studies observed significant variations in acrylamide concentrations, which complicate risk assessment and the establishment of effective control measures. The objective of this study was to obtain an insight into the actual variation in acrylamide concentrations in French fries prepared under typical conditions in a food service establishment (FSE). Besides acrylamide, frying time, frying temperature, and reducing sugars were measured and the actual practices at receiving, thawing and frying during French fries preparation were observed and recorded. The variation in the actual frying temperature contributed most to the variation in acrylamide concentrations, followed by the variation in actual frying time; no obvious effect of reducing sugars was found. The lack of standardised control of frying temperature and frying time (due to inadequate frying equipment) and the variable practices of food handlers seem to contribute most to the large variation and high acrylamide concentrations in French fries prepared in a restaurant type of FSE as compared to chain fast-food services, and institutional caterers. The obtained insights in this study can be used to develop dedicated control measures in FSE, which may contribute to a sustainable reduction in the acrylamide intake.


Assuntos
Acrilamida/química , Culinária/métodos , Gorduras na Dieta/análise , Solanum tuberosum/química , Acrilamida/análise , Manipulação de Alimentos , Serviços de Alimentação , Temperatura Alta , Humanos
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