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1.
Neoplasma ; 65(2): 234-241, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29534585

RESUMO

Early diagnosis of bladder cancer is crucial for improvement of cancer specific survival and recurrence rate. We analyzed the possible role of fluorescence urine analysis in bladder cancer diagnosis. The cohort consisted of 20 healthy controls, 40 patients with hematuria and 75 patients with hematuria and histologically proven bladder tumor. Synchronous fluores- cence spectra with a 70 nm wavelength difference were recorded for (1:1-1:128) urine dilutions. Concentration matrices of synchronous spectra (CMSS) were used to classify samples into tested groups. CMSS analysis allowed us to distinguish patients with tumor from patients with hematuria with a sensitivity 55% and specificity 74.7%. This is comparable to the sensitivity and specificity of other non-invasive tests like BTA stat and nmP-22 (Bladder check®). Lower fluorescence inten- sity of Imax 280 nm and ratio of 280 nm to 450 nm was found to be associated with the presence of tumor. We have found an association of decreased fluorescence with the stage of the disease. Our data suggest that CMSS urine analysis has a potential role in the non-invasive diagnostic tests for bladder cancer, but it cannot replace the current diagnostic algorithm yet.


Assuntos
Espectrometria de Fluorescência , Urinálise , Neoplasias da Bexiga Urinária/diagnóstico , Biomarcadores Tumorais , Fluorescência , Hematúria , Humanos , Sensibilidade e Especificidade , Neoplasias da Bexiga Urinária/urina
2.
J Photochem Photobiol B ; 153: 191-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26414289

RESUMO

Pteridines belong to a class of fluorescent metabolites that are excreted by humans in urine and their concentrations can reflect various pathophysiological states. We quantified the differences in urinary pteridine levels in patients with malignant and benign ovarian tumors and in healthy individuals. Urine samples were centrifuged and supernatants were oxidized by MnO2 before analysis. Levels of neopterin, biopterin, and pterin were assessed by fluorescence analysis of human urine after HPLC separation. We have revealed that the median neopterin levels were higher in urine samples from patients with malignant (0.226 µmol/mmol creatinine) and benign ovarian tumors (0.150 µmol/mmol creatinine) than in healthy subjects (0.056 µmol/mmol creatinine). The median neopterin levels of patients with malignant tumors were higher (1.5-times) than in patients with benign tumors. The median biopterin level in urine of patients with benign ovarian tumors (0.268 µmol/mmol creatinine) was found to be very close to the level in patients with malignant ovarian tumors (0.239 µmol/mmol creatinine), and both were higher than in healthy samples (0.096 µmol/mmol creatinine). The levels of urine pterin followed a pattern similar to neopterin levels for both ovarian tumors, but their concentrations were about three times lower than neopterin levels.


Assuntos
Neoplasias Ovarianas/patologia , Pteridinas/urina , Adulto , Idoso , Biopterinas/urina , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Compostos de Manganês/química , Pessoa de Meia-Idade , Neopterina/urina , Neoplasias Ovarianas/metabolismo , Óxidos/química , Pteridinas/metabolismo
3.
Neoplasma ; 62(3): 500-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25869797

RESUMO

Early diagnosis of ovarian cancer could lead to decreased mortality. We assessed the possible use of urine autofluorescence analysis in its diagnostics and screening.We analysed urine from 42 healthy volunteers, 35 patients with benign, and 36 patients with malignant ovarian tumors. Synchronous fluorescence spectra with a 70 nm wavelength difference were recorded for (1:1 - 1:1024) urine dilutions. Concentration matrices of synchronous spectra (CMSS) were used to classify samples into tested groups.CMSS analysis allowed us to distinguish patients with malignant tumors from healthy ones with a high sensitivity (91.67 %) and specificity (100 %), a positive predictive value (PPV) 100 % and a negative predictive value (NPV) 93.33 %. However, discrimination between benign and malignant ovarian tumors was weaker, with sensitivity 86.11 %, specificity 77.14 %, PPV 79.49 % and NPV 84.38 %. Fluorescence intensity and the position of peaks at 330 and 360 nm were found to be associated with the grade and stage, suggesting that different fluorescent metabolites may prevail at different stages of the disease.CMSS analysis of urine provides an alternative for ovarian cancer screening method development and could be used as a diagnostic test to detect the recurrence of the disease after therapy.

4.
Physiol Res ; 63(Suppl 4): S593-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25669690

RESUMO

Chronic kidney disease (CKD) is associated with increased concentration of intracellular calcium, which is pathological and may lead to irreversible damage of cell functions and structures. The aim of our study was to investigate the impact of 6 months vitamin D(3) supplementation (14 000 IU/week) on free cytosolic calcium concentration ([Ca(2+)](i)) and on the plasma membrane calcium ATPase (PMCA) activity of patients with CKD stage 2-3. PMCA activity of patients was also compared to that of healthy volunteers. Vitamin D(3) supplementation of CKD patients resulted in the decrease of [Ca(2+)](i) (119.79+/-5.87 nmol/l vs. 105.36+/-3.59 nmol/l, n=14, P<0.001), whereas PMCA activity of CKD patients (38.75+/-22.89 nmol P(i)/mg/h) remained unchanged after vitamin D(3) supplementation (40.96+/-17.74 nmol P(i)/mg/h, n=14). PMCA activity of early stage CKD patients before supplementation of vitamin D(3), was reduced by 34 % (42.01+/-20.64 nmol P(i)/mg/h) in comparison to healthy volunteers (63.68+/-20.32 nmol P(i)/mg/h, n=28, P<0.001). These results indicate that vitamin D(3) supplementation had a lowering effect on [Ca(2+)](i) and negligible effect on PMCA activity in CKD patients.


Assuntos
Cálcio/metabolismo , Colecalciferol/uso terapêutico , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Insuficiência Renal Crônica/enzimologia , Deficiência de Vitamina D/prevenção & controle , Adulto , Idoso , Estudos de Casos e Controles , Suplementos Nutricionais , Voluntários Saudáveis , Humanos , Pessoa de Meia-Idade , Insuficiência Renal Crônica/complicações , Deficiência de Vitamina D/enzimologia , Deficiência de Vitamina D/etiologia
5.
Neoplasma ; 60(5): 533-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23790172

RESUMO

Early diagnostics of ovarian cancer is difficult, because there are no symptoms until the disease has progressed to an advanced stage. As urine contains many intrinsic fluorophores, modern fluorescence techniques are perspective candidates for new routine urine tests. The presented work deals with differences in the fluorescence of metabolites in urine of ovarian cancer patients comparing to healthy volunteers using the fluorescence excitation-emission matrices. The most serious differences were found in undiluted urine at the fluorescence emission wavelengths from 400 nm to 460 nm when excited at 310 - 390 nm. Statistical analyses of our data have shown a 5-fold reduction in the intensity of the peak at 330/420 nm (excitation/emission wavelength) for undiluted urine samples excreted by cancer patients as compared to those of normal donors. Moreover, the ratio of intensities of the peaks at 370/440 nm and at 330/420 nm is 18-times elevated in urine excreted by patients with ovarian cancer as compared to healthy urine samples. The observed changes could be interpreted as reduction of the presence of pyridoxic acid, whereas blue-fluorescing pteridines becomes dominant in excitation-emission matrices of cancer urine samples in comparison to healthy donors. We suggest pteridines, which are related to cellular metabolism, as suitable candidates for neoplasia-associated fluorescent markers in human urine. Our work showed that monitoring of human urine fluorescent metabolites offers an alternative for ovarian cancer screening.


Assuntos
Detecção Precoce de Câncer/métodos , Neoplasias Ovarianas/urina , Pteridinas/urina , Urina/química , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Imagem Óptica , Espectrometria de Fluorescência , Urinálise
6.
Bioelectrochemistry ; 87: 226-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22425286

RESUMO

Chronic kidney disease (CKD) is progressive loss of renal function associated among others with increased intracellular calcium concentration. The purpose of this study was to identify the effects of CKD on cell membrane properties such as human red blood cell Ca(2+) ATPase activity, lymphocyte plasma membrane P2X(7) receptor expression and function. This could help us in elucidating the origin of increased calcium concentration in blood cells. We found out Ca(2+) ATPase activity is decreased in early stage CKD patients resulting in altered calcium removal from cytoplasm. By means of flow cytometry we assessed that P2X(7) receptor expression on lymphocyte membrane is 1.5 fold increased for CKD patients. Moreover, we detected an increased uptake of ethidium bromide through this receptor in CKD at basal conditions. It means CKD lymphocyte membranes contain more receptors which are more permeable thus allowing increased calcium influx from extracellular milieu. Finally, we can state alterations in blood cell membranes are closely linked to CKD and may be responsible for intracellular calcium accumulation.


Assuntos
ATPases Transportadoras de Cálcio/metabolismo , Cálcio/metabolismo , Eritrócitos/metabolismo , Rim/metabolismo , Linfócitos/metabolismo , Insuficiência Renal Crônica/metabolismo , Transporte Biológico , Estudos de Casos e Controles , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular , Citoplasma/metabolismo , Eritrócitos/patologia , Etídio/metabolismo , Feminino , Citometria de Fluxo , Expressão Gênica , Humanos , Rim/patologia , Linfócitos/patologia , Masculino , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2X7/metabolismo , Insuficiência Renal Crônica/patologia
7.
Physiol Res ; 57 Suppl 2: S67-S73, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18373390

RESUMO

The aim of present study was to investigate functional and physical alterations in membranes of heart mitochondria that are associated with remodeling of these organelles in acute phase of streptozotocin-induced diabetes and to elucidate the role of these changes in adaptation of the heart to acute streptozotocin-induced diabetes (evaluated 8 days after single dose streptozotocin application to male Wistar rats). Action of free radicals on the respiratory chain of diabetic-heart mitochondria was manifested by 17 % increase (p<0.05) in oxidized form of the coenzyme Q(10) and resulted in a decrease of states S3 and S4 respiration, the respiratory control index, rate of phosphorylation (all p<0.01) and the mitochondrial transmembrane potential (p<0.05), but the ADP/O ratio decreased only moderately (p>0.05). On the contrary, membrane fluidity and the total mitochondrial Mg2+-ATPase activity increased (both p<0.05). In diabetic heart mitochondria, linear regression analysis revealed a reciprocal relationship between the increase in membrane fluidity and decrease in trans-membrane potential (p<0.05, r = 0.67). Changes in membrane fluidity, transmembrane potential, Mg2+-ATPase activity and the almost preserved ADP/O ratio appear as the manifestation of endogenous protective mechanisms participating in the functional remodeling of mitochondria which contributes to adaptation of the heart to diabetes.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Mitocôndrias Cardíacas/metabolismo , Membranas Mitocondriais/metabolismo , Miocárdio/metabolismo , Adaptação Fisiológica , Animais , ATPase de Ca(2+) e Mg(2+)/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Transporte de Elétrons , Radicais Livres/metabolismo , Masculino , Fluidez de Membrana , Potencial da Membrana Mitocondrial , Mitocôndrias Cardíacas/enzimologia , Miocárdio/enzimologia , Fosforilação Oxidativa , Ratos , Ratos Wistar , Ubiquinona/análogos & derivados , Ubiquinona/metabolismo
8.
Physiol Res ; 55(2): 189-194, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-15910177

RESUMO

The objective of this study was to investigate the response of Na(+)/K(+)-ATPase of human erythrocytes to green laser irradiation. Effects of green laser light of fluences 9.5-63.3 J.cm(-2) and merocyanine 540-mediated laser light treatment were studied. Isolated erythrocyte membranes (protein concentration of 1 mg/ml) were irradiated by Nd:YAG laser (532 nm, 30 mW) and then incubated in a medium with 2 mM ATP for 30 min. Activity of ATPase was determined colorimetrically by measuring the colored reaction product of liberated inorganic phosphate and malachite green at 640 nm. Contribution of Na(+)/K(+)-ATPase to overall phosphate production was determined using ouabain. A positive effect of green laser light on Na(+)/K(+)-ATPase activity was observed. The dependence of enzymatically liberated inorganic phosphate on light fluence showed a linear correlation (R(2)=0.96, P=0.0005) for all fluences applied (9.5-63.3 J.cm(-2)). On the other hand, MC 540-mediated phototreatment caused a suppression of enzyme activity.


Assuntos
Eritrócitos/efeitos da radiação , Lasers , ATPase Trocadora de Sódio-Potássio/efeitos da radiação , Cor , Corantes Fluorescentes , Humanos , Terapia com Luz de Baixa Intensidade , Pirimidinonas
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