997 resultados para BIOLOGICAL MARKER
Resumo:
Bone morphogenetic proteins (BMPs) are cytokines involved in proliferation and angiogenesis of many kind of human cancer. The present study analyzed the immunohistochemical expression of BMP-2, BMPR-II, BMPR-IA and endoglin (CD105) and their relationship with the biological behavior and local angiogenesis in tongue oral squamous cells carcinoma (SCC). The sample consisted of 25 cases of tongue SCC without metastasis, 25 tongue SCC with metastasis and 25 cases of Inflamatory Fibrous Hyperplasia (IFH).The histological grade of malignancy proposed by Bryne (1998), adapted by Miranda (2002) was used to classify all tongue SCC cases. Score 0 was attributed to absent-weak immunoexpression and score 1 for strong immunostaning and pattern of distribution was focal or diffuse. Microvessel counts (MVC) was established for CD105. Most of the patients with tongue SCC was male. The principal age in tongue SCC without metastasis was over 65 years and in tongue SCC with metastasis was between 45-65 years. There were predominance of stage II in TNM and in the specimens with high-grade, independent of studied group. For BMP-2, 56% of tongue SCC without metastasis and 72% tongue SCC with metastasis exhibited score 1 while the IFH showed secore 0 in 72% of the cases, with statistical association (p=0,007). Considering the BMPR-II, 52% of tongue SCC without metastasis exhibited score 0; 56% tongue SCC with metastasis and 60% IFH showed score 1. The majority cases of BMPR-IA demonstrated score 1 and 100% of CD105 exhibited strong immunoexpression in tongue SCC. Regarding the pattern distribution, it was noted a tendency to diffuse pattern for the proteins in all groups. The means of MVC were similar in tongue SCC without metastasis (32,91) and in tongue SCC with metastasis (32,05), however existed statistical difference with IFH (p<0,001). There was statistical association of BMP-2 expression with BMPR-II (p=0,008), BMPR-IA (p=0,006) and CD105 (p=0,046). An association between TNM and BMP-2 immunoexpression and their receptors was not detected, nevertheless this association was found with MVC (p=0,047) whose averages were higher for the stages II (35,97) e IV (35,69). No association between histological grading and these proteins was observed. This study suggests that the superexpression of BMP-2 signaling pathways acts on cell proliferation in tongue SCC and can be implicated with more invasive potential. Additionaly, the CD105 is a potent biological marker of neovascularization in this neoplasm and their association with BMP-2 and BMPR-IA receptor, showed that this type of cancer in BMP-2 is presented as pro-angiogenic in the metastatic process
Resumo:
This paper presents a simple, fast and sensitive method to determine chromic oxide (used as a biological marker of fish feed) in samples of fish feces by GFAAS through the direct introduction of slurries of the samples into the spectrometer's graphite tube. The standard samples of feces and of fish feed containing 0.10-1.00 mg kg(-1) of Cr2O3 were pre-frozen for I min in liquid nitrogen and then ground a cryogenic mill for 2 min, which reduced the samples' grain size to less than 60 mu m. The standard slurries were prepared by mixing 20 mg of standard samples of fish feed or feces with I mL of a solution containing 0.05% (v/v) of Triton X-100 and 0.50% (v/v) of suprapure HNO3 directly in the spectrometer's automatic sampling glass. The final concentrations of Cr2O3 present in the standard slurries were 2, 4, 8, 16 and 20 mu g L-1. After sonicating the mixture for 20s, 10 mu L of standard slurries were injected into the graphite tube, whose internal wall was lined with a metallic palladium film that acted as a permanent chemical modifier. The limits of detection (LOD) and quantification (LOQ) calculated for 20 readings of the blank of the standard slurries (2%, m/v of feces or feed devoid of minerals) were 0.81 and 2.70 mu g L-1 of Cr2O3 for the standard feces slurries, 0.84 and 2.83 mu g L-1 of Cr2O3 for the standard feed slurries. The proposed method was applied in studies of nutrient digestibility of different fish feeds and its results proved compatible with the results obtained from samples pre-mineralized by acid digestion. (c) 2005 Elsevier B.V. All rights reserved.
Resumo:
A sensibilidade do método espectrofotométrico da s-difenilcarbazida de determinação do crômio permite que esse metal possa ser determinado em teores e em massas de amostras tão pequenas que as concentrações atualmente usadas de óxido de crômio (III) como marcador externo em ensaios biológicos poderiam ser drasticamente diminuídas. Utilizando-se do piauçu (Leporinus macrocephalus) para um estudo sobre o coeficiente de digestibilidade aparente (CDA) da fração protéica, seis níveis de óxido de crômio (III) - 0,01% - 0,02% - 0,03% - 0,05% - 0,1% e 0,2% - foram incorporados em dietas isoprotéica e isoenergética, objetivando-se verificar se o cálculo do CDA seria afetado pela variação do teor do marcador. Os seis tratamentos foram dispostos em um delineamento em blocos inteiramente casualisados, sendo as fezes coletadas durante 16 dias. Verificou-se que os resultados do coeficiente de digestibilidade aparente da fração protéica não apresentaram diferenças estatísticas significativas devidas aos teores incorporados do marcador à ração e aos dias de coleta. Conseqüentemente, e em experimentos dessa natureza, nada impede que seja reduzido o teor de óxido de crômio (III) ao menos até 0,01%: além da economia relativa ao consumo do mesmo e da facilidade na manipulação de menor quantidade de amostras de fezes, o método espectrofotométrico da s-difenilcarbazida permite dosar esse nível (e até menor do que 0,01%) de modo simples e rápido, com precisão e exatidão.
Resumo:
As peroxidases, presentes nos peroxissomos e lisossomos, pertencem às oxidases e atuam como catalítico para o peróxido de hidrogênio (H2O2), posteriormente decomposto pela oxidação de cossubstratos, evitando danos celulares.(¹) Foi aplicada a técnica da peroxidase(2) em esfregaços sanguíneos de Phrynops geoffroanus, comparando com sangue humano, para avaliação da atividade e controle da reação. O esfregaço sanguíneo humano apresentou marcações em neutrófilos, fagócitos com muitos lisossomos e peroxissomos (Figura 1). Nos esfregaços sanguíneos de Phrynops geoffroanus, as marcações apresentaram-se nos basófilos (Figura 2), que representam de 10% a 25% dos leucócitos de quelônios e possuem grande número de granulações citoplasmáticas,(3) sugerindo a presença de grande quantidade de enzimas e organelas como lisossomos e peroxissomos, possivelmente associadas a sua participação em reações imunes. A atividade peroxidásica representa resposta do organismo a ações ambientais danosas, servindo como marcador biológico.
Resumo:
O objetivo deste estudo foi ajustar o método espectrofotométrico da 1,5-difenilcarbazida à determinação do crômio em fezes, como marcador biológico, adequando-o à rotina laboratorial. Fatores que poderiam exercer interferência na transformação do crômio (III) à crômio (VI) foram testados, como a recuperação do metal, quantidade de amostra, quantidade e ordem de emprego dos ácidos oxidantes da digestão úmida, temperatura e tempo de digestão e perda por volatilização do crômio como cloreto de cromila, porém não se determinou estatisticamente interferência destes fatores. No método ajustado, a amostra é digerida pela clássica mistura ácida nítrica/perclórica, levando a oxidação do crômio (III) a crômio (VI), e alíquota do extrato diluído é usado para reação com 1,5-difenilcarbazida; as absorbâncias são medidas a 550nm, utilizando-se de cubetas de um centímetro de caminho óptico, contra prova em branco conduzida simultaneamente. Dicromato de potássio foi empregado como substância de referência para obtenção da curva padrão na faixa de 0,25 - 2,5mg.mL-1 de Cr2O3 (1mg Cr2O3 º 1,9355mg K2Cr2O7).
Resumo:
Objective - To evaluate the reliability of urine carnitine concentrations measured in single postprandial samples, compared with carnitine concentrations measured in 24-hour urine samples. Animals - 19 healthy Beagles. Procedure - After emptying the urinary bladder by catheterization, dogs were fed a canned canine maintenance diet. Approximately 8 hours later, urine, plasma, and serum samples were obtained for determination of urinary carnitine fractional excretion and urine carnitine-to-creatinine concentration ratio. Results were compared with 24-hour urinary carnitine excretion rate. Results - Fractional excretion of carnitine and urine carnitine-to-creatinine ratios correlated poorly with 24-hour urinary carnitine excretion. Conclusion - Determination of 24-hour urinary carnitine excretion is recommended to measure urine carnitine concentrations in dogs.
Resumo:
Inhibins are dimeric glycoproteins composed of an α-subunit and a βA-subunit (inhibin A) or βB-subunit (inhibin B), which inhibits pituitary gonadotropin secretion of FSH. The inhibin B is a product of the cohort of antral follicles. The ovarian follicle number decrease steadily as a function of increasing age, with consequent falls in the levels of inhibin B and increase of FSH levels. It is sufficient to maintain ovulatory function and continued secretion of estradiol. Elevated FSH levels seem to occur late in the sequence of events associated with ovarian failure. The inhibin B, produced by granulosa cells, is the earliest marker of the decline in ovarian follicular reserve across reproductive aging.
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Although systemic hypertension is very common in patients with glomerulonephritis there is a dispute if this alteration is consequence of the glomerulonephritis per se or is a consequence of the renal failure secondary to the glomerular lesion. With the aim to analyze the factors associated with systemic hypertension, 196 patients with different forms of nephritis were studied. The systemic arterial pressure was measured by standard sphygmomanometer, renal function was evaluated by the determination of the serum creatinine concentration or creatinine clearance. The diagnosis of the type of glomerulonephritis was made on the basis of an examination of kidney biopsy specimens. The prevalence of arterial hypertension among patients with glomerulonephritis was 62.7%. The hypertensive patients were older (hypertensive = 30.6 ± 12.8; normotensive = 25.4 ± 1.6 years; P = 0.03). The prevalence of arterial hypertension was lower in patients with minimal glomerular lesion (12.5%), though their ages were also lower (18.1 ± 3.6 and 29.1 ± 1.03 years; P = 0.03). Arterial hypertension did not correlate with the serum levels of creatinine and albumin; creatinine clearance and 24-h proteinuria. In conclusion: In the patients with glomerulonephritis, the presence of arterial hypertension was associated with a higher mean age whereas the intensity of proteinuria, the level of renal function or the type of glomerulonephritis was not different between the two groups.
Resumo:
Dietary modification ought to be the first line of strategy in prevention of the development of cardiac disease. The purpose of this study was to investigate whether dietary restriction, dietary-fibre-enriched diet, and their interactions might affect antioxidant capacity and oxidative stress in cardiac tissue. Male Wistar rats (180-200 g; n = 10) were divided into four groups: control ad libitum diet (C), 50% restricted diet (DR), fed with fibre-enriched diet (F), and 50% restricted fibre-enriched diet (DR-F). After 35 days of the treatments, F, DR, and DR-F rats showed low cholesterol, LDL-cholesterol, and triacylglycerol, and high HDL-cholesterol in serum. The DR, DR-F, and F groups had decreased myocardial lipoperoxide and lipid hydroperoxide. The DR-F and F treatments increased superoxide dismutase and glutatione peroxidase (GSH-Px). The DR treatment increased GSH-Px and catalase activities. Dietary fibre beneficial effects were related to metabolic alterations. The F and DR-F groups showed high cardiac glycogen and low lactate dehydrogenase/citrate synthase ratios, indicating diminished anaerobic and elevated aerobic myocardial metabolism in these animals. There was no synergistic effect between dietary restriction and dietary fibre addition, since no differences were observed in markers of oxidative stress in the F and DR-F groups. Dietary fibre supplementation, rather than energy intake and dietary restriction, appears to be the main process retarding oxidative stress in cardiac tissue.
Resumo:
Protein malnutrition leads to functional impairment in several organs, which is not fully restored with nutritional recovery. Little is known about the role of oxidative stress in the genesis of these alterations. This study was designed to assess the sensitivity of blood oxidative stress biomarkers to a dietary protein restriction. Male Wistar rats were divided into two groups, according to the diet fed from weaning (21 days) to 60 day old: normal protein (17% protein) and low protein (6% protein). Serum protein, albumin, free fatty acid and liver glycogen and lipids were evaluated to assess the nutritional status. Blood glutathione reductase (GR) and catalase (CAT) activities, plasma total sulfhydryl groups concentration (TSG) as well as plasma thiobarbituric acid reactive substances (TBARs) and reactive carbonyl derivatives (RCD) were measured as biomarkers of the antioxidant system and oxidative damage, respectively. The glucose metabolism in soleus muscle was also evaluated as an index of stress severity imposed to muscular mass by protein malnutrition. No difference was observed in muscle glucose metabolism or plasma RCD concentration between both groups. However, our results showed that the low protein group had higher plasma TBARs (62%) concentration and lower TSG (44%) concentration than control group, indicating increased reactive oxygen species production in low protein group. The enhancement of erythrocyte GR (29%) and CAT (28%) activities in this group also suggest an adaptation to the stress generated by the protein deficiency. Taken together, the results presented here show that the biomarkers used were able to reflect the oxidative stress level induced by this specific protein deficient diet.
Resumo:
Morphological, cytochemical and ultrastructural studies are important to demonstrate the function of the blood cells, which is very little understood in teleosts. In peripheral blood of piracanjuba' Brycon orbignyanus, thrombocytes, lymphocytes, monocytes, neutrophils and heterophils were studied and characterized. Thrombocytes had a fusiform or oval shape with PAS-positive granules. Lymphocytes presented small size with sparse basophilic cytoplasm. Monocytes were large in size, presented basophilic cytoplasm that may be foamy or vacuolated, with non-specific esterase staining. The neutrophils presented lightly neutrophilic granule cytoplasm, with positivity for PAS and peroxidase. The heterophils were large in size, with eosinophilic and basophilic granules cytoplasm and PAS-positive. Transmission electron microscopy study demonstrated that the thrombocytes, lymphocytes and monocytes features were similar to other teleosts. In ultrastructural study only one type of neutrophils was observed. Cytochemical findings indicated that neutrophils and monocytes of B. orbignyanus may be involved in phagocytosis, and neutrophils play an important microbicidal role.
Resumo:
This study evaluated the efficacy of dietary vitamin C (ascorbic acid or AA), vitamin E (α-tocopherol or α-T), and C + E supplementation on the blood parameters of Arapaima gigas grown in net cages for 45 days. Four treatments were tested: control (commercial feed); C800; E500 and C + E (800 + 500) with supplementation of 800 mg AA kg- 1, 500 mg α-T kg- 1 and 800 + 500 mg AA + α-T kg- 1, respectively. Hematocrit (Ht), red blood cells (RBC), and hemoglobin concentration (Hb) (oxidative status indicators), thrombocytes and leukocytes (immunological indicators), plasma protein and glucose were evaluated. Fish fed vitamin C and C + E supplemented diets showed greater weight gain and survival. Dietary vitamin C and C + E diet supplementation resulted in increased Ht, Hb, RBC, MCHC, total leukocytes, total proteins, thrombocytes and eosinophils compared to the control and α-T. The α-tocopherol-supplemented diet reduced the number of total thrombocytes, lymphocytes and neutrophils and increased glucose and eosinophils relatively to the control. In general, leukocytes and thrombocytes were good indicators of the efficiency of vitamin on the defense mechanism of the A. gigas reared in cages. Results indicate that high α-T diet supplementation provides no benefit for the maintenance of the oxidative or the immunological status of A. gigas. However, it was demonstrated that high dietary AA improves A. gigas immunological status. Red blood cell indices and immune system indicators showed no synergistic effect between the vitamins after supplementing the A. gigas diet with α-T + AA. © 2006 Elsevier Inc. All rights reserved.
Resumo:
PURPOSE: Subclinical inflammation may be observed in patients using topical antiglaucomatous drugs. The objective of this study was to investigate inflammation in conjunctiva of glaucoma patients using prostaglandin analogs, by the detection of an immunogenetic marker (HLA-DR) and compare the effect of 3 different drugs: latanoprost, bimatoprost, and travoprost in the induction of this inflammation. SUBJECTS AND METHODS: Thirty-three patients with primary open-angle glaucoma were evaluated without and with prostaglandin analogs topical therapy. Imprints of conjunctival cells were obtained, fixed on glass slides, and prepared for immunohistochemical analysis. RESULTS: Before the use of prostaglandin analogs, 4 of the 33 patients evaluated presented expression of HLA-DR in the conjunctiva (mild). After 1 month on prostaglandin analog treatment, all but 1 patient presented HLA-DR staining. HLA-DR expression of these 32 patients was scored as mild (19 patients), medium (11 patients), or intense (2 patients). The differences were statistically significant both when the presence and the increased expression of HLA-DR were considered (P<0.001). When the 3 different groups were analyzed (latanoprost, bimatoprost, and travoprost) no statistically significant difference was found (P=0.27). CONCLUSIONS: The use of prostaglandin analogs eye drops provokes a subclinical inflammatory reaction, observed by HLA-DR expression, even after a short period of treatment, independently of the class of the prostaglandin analogs used. © 2009 Lippincott Williams & Wilkins, Inc.
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The aims of this study were to characterize the microstructure of a commercially pure titanium (cpTi) surface etched with HCl/H 2SO 4 (AE-cpTi) and to investigate its in vitro cytocompatibility compared to turned cpTi (T-cpTi). T-cpTi showed a grooved surface and AE-cpTi revealed a surface characterized by the presence of micropits. Surface parameters indicated that the AE-cpTi surface is more isotropic and present a greater area compared to T-cpTi. The oxide film thickness was similar between both surfaces; however, AE-cpTi presented more Ti and O and less C. Osteoblastic cell proliferation, alkaline phosphatase activity, and bone-like nodule formation were greater on T-cpTi than on AE-cpTi. These results show that acid etching treatment produced a surface with different topographical and chemical features compared to the turned one, and such surface modification affected negatively the in vitro cytocompatibility of cpTi as demonstrated by decreasing culture growth and expression of osteoblastic phenotype.
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Fossil fuels such as diesel are being gradually replaced by biodiesel, a renewable energy source, cheaper and less polluting. However, little is known about the toxic effects of this new energy source on aquatic organisms. Thus, we evaluated biochemical biomarkers related to oxidative stress in Nile tilapia (Oreochromis niloticus) after two and seven exposure days to diesel and pure biodiesel (B100) and blends B5 and B20 at concentrations of 0.01 and 0.1mLL -1. The hepatic ethoxyresorufin-O-deethylase activity was highly induced in all groups, except for those animals exposed to B100. There was an increase in lipid peroxidation in liver and gills in the group exposed to the higher concentration of B5. All treatments caused a significant increase in the levels of 1-hydroxypyrene excreted in the bile after 2 and 7d, except for those fish exposed to B100. The hepatic glutathione-S-transferase increased after 7d in animals exposed to the higher concentration of diesel and in the gill of fish exposed to the higher concentration of pure diesel and B5, but decreased for the two tested concentrations of B100. Superoxide dismutase, catalase and glutathione peroxidase also presented significant changes according to the treatments for all groups, including B100. Biodiesel B20 in the conditions tested had fewer adverse effects than diesel and B5 for the Nile tilapia, and can be suggested as a less harmful fuel in substitution to diesel. However, even B100 could activate biochemical responses in fish, at the experimental conditions tested, indicating that this fuel can also represent a risk to the aquatic biota. © 2011 Elsevier Ltd.