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1.
Braz. j. med. biol. res ; 52(8): e8688, 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1011611

RESUMEN

The objective of this study was to investigate the effect of whole body vibration (WBV) exercise on oxidative stress markers in a group of women with fibromyalgia (FM) compared to a group of healthy women (CT). Twenty-one women diagnosed with FM and 21 age- and weight-matched healthy women were enrolled the study. Plasma oxidative stress markers (primary outcomes) were evaluated at rest and after WBV, and included thiobarbituric acid reactive substances (TBARS), iron reduction capacity (FRAP), superoxide dismutase antioxidant enzymes activity (SOD), and catalase (CAT). At rest, the FM group had higher TBARS (P<0.001) and FRAP (P<0.001), and lower CAT (P=0.005) compared to the CT. In the CT group, the WBV had no effect on TBARS (P=0.559) and FRAP (P=0.926), whereas it increased both SOD (P<0.001) and CAT (P<0.001). In the FM group, the WBV reduced TBARS (p <0.001), FRAP (P<0.001), and CAT (P=0.005), while it increased SOD (P=0.019). There was an interaction effect (moments vs groups) in the TBARS (effect size=1.34), FRAP (effect size=0.93), CAT (effect size=1.45), and SOD (effect size=1.44) (P<0.001). A single trial of WBV exercise improved all oxidant and antioxidant parameters towards a greater adaptation to the stress response in FM women.


Asunto(s)
Humanos , Vibración , Biomarcadores/sangre , Fibromialgia/sangre , Estrés Oxidativo/fisiología , Fibromialgia/fisiopatología , Estudios de Casos y Controles
2.
Braz. j. med. biol. res ; 40(1): 77-80, Jan. 2007. tab
Artículo en Inglés | LILACS | ID: lil-439670

RESUMEN

The aim of the present study was to determine the effect of the oral ingestion of an extract of the herb Uncaria tomentosa (cat's claw) on the biodistribution of the radiobiocomplex sodium pertechnetate (Na99mTcO4) in rats. The animals (male Wistar rats, 2 months old, 180-220 g), were treated (1 mL) with an U. tomentosa extract (32 mg/mL, N = 5) or 0.9 percent NaCl solution (control, N = 5) for 7 days. After this period, Na99mTcO4 (3.7 MBq, 0.3 mL) was injected through the ocular plexus and after 10 min the rats were killed, the organs isolated and counted in a well-gamma counter. A significant (P < 0.05) alteration in Na99mTcO4 uptake i) from 0.57 ± 0.008 to 0.39 ± 0.06 percentATI/organ (P < 0.05) and from 0.57 ± 0.17 to 0.39 ± 0.14 percentATI/g (P < 0.05) was observed in the heart, ii) from 0.07 ± 0.02 to 0.19 ± 0.07 percentATI/g in the pancreas, and iii) from 0.07 ± 0.01 to 0.18 ± 0.07 percentATI/g (P < 0.05) in muscle after treatment with this extract. Although these results were obtained with animals, caution is advisable in the interpretation of the nuclear medicine examination when the patient is using this herb. This finding is probably an example of drug interaction with a radiopharmaceutical, a fact that could lead to misdiagnosis of the examination in clinical practice with unexpected consequences for the patient.


Asunto(s)
Animales , Masculino , Ratas , Uña de Gato/química , Radiofármacos/farmacocinética , /farmacocinética , Extractos Vegetales/farmacología , Ratas Wistar , Distribución Tisular/efectos de los fármacos
3.
Rev. bras. eng. biomed ; 20(2/3): 73-79, dez. 2004. ilus, graf
Artículo en Inglés | LILACS | ID: lil-495486

RESUMEN

In nuclear medicine, stannous, as stannous chloride (SnCl2) and stannous fluoride (SnF2), are used as reducing agents to obtain radiopharmaceuticals labeled with technetium-99m. In the literature, the SnCl2 action was studied and it seems to be mediated through free radicals (FR) production in a Fenton-like reaction. In this work it was evaluated: (i) the in vitro SnF2 effects in different concentrations using pBCKS plasmid deoxyribonucleid acid (DNA); (ii) the SnF, effects in different Escherichia coli (E.coli) cultures, proficient or deficient in DNA repair genes, treated simultaneously with FR scavengers; and (iii) the biological effects of Maytenus ilicifolia, Baccharis genistelloides and Cymbopogon citratus aqueous extracts on the SnCL2 action in E.coli culture. The SnF2 treatment induced plasmidd DNA damages (single and double DNA strand breaks), in a dose-dependent manner. Citotoxicity mediated by SNf2 was observed and the simultaneous tratment with FR scavengers has increased the cell survival, suggesting the participation of FR on the SnF2-deleterious effects. The vegetal extrracts prottected the E.coli cells agains the SnCl2 effects. The components of the extracts could be interacting with SnCl2 blocking its participation in the FR formation.


Asunto(s)
Compuestos Orgánicos de Estaño/efectos adversos , ADN , Radicales Libres/efectos adversos , Antioxidantes , Radiofármacos
4.
Braz. j. med. biol. res ; 37(2): 267-271, Feb. 2004. ilus, tab
Artículo en Inglés | LILACS | ID: lil-354180

RESUMEN

Ginkgo biloba extract (EGb) is a phytotherapeutic agent used for the treatment of ischemic and neurological disorders. Because the action of this important extract is not fully known, assays using different biological systems need to be performed. Red blood cells (RBC) are labeled with technetium-99m (Tc-99m) and used in nuclear medicine. The labeling depends on a reducing agent, usually stannous chloride (SnCl2). We assessed the effect of different concentrations of EGb on the labeling of blood constituents with Tc-99m, as sodium pertechnetate (3.7 MBq), and on the mobility of a plasmid DNA treated with SnCl2 (1.2 æg/ml) at room temperature. Blood was incubated with EGb before the addition of SnCl2 and Tc-99m. Plasma (P) and RBC were separated and precipitated with trichloroacetic acid, and soluble (SF-P and SF-RBC) and insoluble (IF-P and IF-RBC) fractions were isolated. The plasmid was incubated with Egb, SnCl2 or EGb plus SnCl2 and agarose gel electrophoresis was performed. The gel was stained with ethidium bromide and the DNA bands were visualized by fluorescence in an ultraviolet transilluminator system. EGb decreased the labeling of RBC, IF-P and IF-RBC. The supercoiled form of the plasmid was modified by treatment with SnCl2 and protected by 40 mg/ml EGb. The effect of EGb on the tested systems may be due to its chelating action with the stannous ions and/or pertechnetate or to the capability to generate reactive oxygen species that could oxidize the stannous ion.


Asunto(s)
Humanos , Animales , ADN , Eritrocitos , Ginkgo biloba , Plásmidos , Proteínas Sanguíneas , Electroforesis en Gel de Agar , Eritrocitos , Marcaje Isotópico , Extractos Vegetales , Pertecnetato de Sodio Tc 99m , Tecnecio
5.
Braz. j. med. biol. res ; 31(2): 303-6, feb. 1998. tab
Artículo en Inglés | LILACS | ID: lil-212577

RESUMEN

In the present study evaluated the binding of the radiopharmaceuticals sodium pertechnetate (Na (99m)TcO4), methylenediphosphonic acid (99m)Tc-MDP)) and glucoheptonate acid (99m)Tc-GHA)) to blood elements using centrifugation and radioautographic techniques. Heparinized blood was incubated with the labelled compounds for 0, 1, 2, 3, 4, 6 and 24 h. Plasma (P) and blood cells (BC) were isolated and precipitated with 5 percent trichloroacetic acid (TCA), and soluble (SF) and isoluble fractions (IF) were separated. Blood samples were prepared (0 and 24 h) and coated with LM-1 radioautographic emulsions and percent radioactivity (percent rad) in P and BC was determined. The binding of Na (99m)TcO4 (percentrad) to P was 61.2 percent (0 h) and 46.0 percent (24 h), and radioautography showed 63.7 percent (0 h) and 43.3 percent (24 h). The binding to BC was 38.8 percent (0 h) and 54.0 percent (24 h), and radioautography showed 36.3 percent (0h) and 56.7 percent (24 h), and radioautography showed 36.3 percent (0 h) and 56.7 percent (24 h). (99m) Tc-MDP study presented 91.1 percent (0 h) to P and 87.2 percent (24 h), and radioautography showed 67.9 percent (0 h) and 67.4 percent (24 h). The binding to BC was 8.9 percent (0 h) and 12.8 percent (24 h), and radioautography showed 32.1 percent (0 h) and 32.6 percent (24 h). (99m)Tc-GHA study was 90.1 percent (0 h) to P and 79.9 percent (24 h), and radioautography showed 67.2 percent (0 h) and 60.1 percent (24 h). The binding to BC was 9.9 percent (0 h) and 20.1 percent (24 h), and radioautography showed 32.8 percent (0 h) and 39.9 percent (24 h). The comparasion of the obtained results suggests that the binding to plasma and blood cells in the two techniques used (radioautography and centrifugation) qualitatively in accordance.


Asunto(s)
Ratas , Animales , Células Sanguíneas/química , Ácidos Fosforosos/sangre , Ácidos Fosforosos/farmacocinética , Radiofármacos/sangre , Radiofármacos/farmacocinética , Pertecnetato de Sodio Tc 99m/sangre , Pertecnetato de Sodio Tc 99m/farmacocinética , Autorradiografía , Centrifugación , Ratas Wistar
6.
Braz. j. med. biol. res ; 28(2): 256-60, Feb. 1995. tab
Artículo en Inglés | LILACS | ID: lil-154274

RESUMEN

Sodium pertechnetate (99mTcO4) and many99m Tc-products are the radiopharmaceuticals most frequently used in nuclear medicine. Using an in vitro model, we evaluated the effect of cyclophosphamide on per cent radioactivity of 99mTcO4 and methylenedi-phosphonic acid (99mTc-MDP) bound toi isolated blood elements. Blood samples were incubated with the two radiopharmaceuticals, plasma and blood cells were separated and precipitated, and soluble and insoluble fractions were separated. To evaluate the effect of cyclophosphamide, blood was incubated with this drug 1h prior to the addition of the radiopharmaceuticals. The fraction of 99mTcO4 radioactivity was slightly higher in plasma (61.2 to 53.8 per cent) than in blood cells (38.8 to 46.2 per cent) up to 6 h and cyclophosphamide did not interfere with this distribution. The amount of 99mTc-mdp radioactivity was higher in plasma (91.1 to 87.2 per cent) than in blood cells 8.9 to 12.9 per cent) up to 24 h and cyclophosphamide did not modify it. The binding of 99mTcO4 to the insoluble fraction of plasma (4.9 to 6.1 per cent) was low and cyclophosphamide did not interfere with it up to 6h, but a small blockade (9.8 to 4.8 per cent) was observed at 24 h. From 3 h on, cyclophosphamide slightly inhibited 99mTcO4 binding to blood cells (23.1 to 16.6 per cent) and increased it at 24h (31.2 to 14.3 per cent). Cyclophosphamide did not alter 99mTc-MDP binding to the insoluble fraction of blood cells and slightly decreased 99mTc-MDP binding to the insoluble fraction of plasma (29.8 to 23.6 per cent) up to 6 h. The effect of cyclophosphamide was strongest at 24 h, with decreased radioactivity binding to the insoluble fraction of plasma (47.6 to 27.0 per cent) and blood cells (51.2 to 23.2 per cent). The fact that cyclophosphamide can bind to plasma proteins and/or cross the cell membrne explains in part the results obtained. Studies using other chemotherapeutic drugs may lead to the development of an in vitro model for the evaluation of drug interaction with radiopharmaceutical substances


Asunto(s)
Humanos , Sangre/efectos de los fármacos , Ciclofosfamida/farmacología , Técnicas In Vitro , /farmacocinética , Medronato de Tecnecio Tc 99m/farmacocinética , Radiactividad
7.
Braz. j. med. biol. res ; 28(1): 131-5, Jan. 1995. tab
Artículo en Inglés | LILACS | ID: lil-153341

RESUMEN

Since the introduction of technetium-99m (99mTc) and its rapid acceptance as a tool in nuclear medicine, very little information is available about is biological action as 99mTc-radiopharmaceuticals. We have determined if cyclophosphamide, an alkylating agent, used in oncology as a chemotherapeutic drug, modifies the binding of 99mTCO-4 and 99mTc-MDP (99mTc-metylenediphosphonic acid) to blood cells and to plasma proteins. The radiopharmaceuticals were injected intravenously (iv) into SW-55 mice (male and female, weight 25 g) and samples of plasma and blood cells were separated. Cyclophosphamide (50 µg) was injected iv 1 h before the radipharmaceuticals. Samples of plasma and blood cells were also precipitated with 5 per cent trichloroacetic acid and soluble and insoluble fractions were isolated. The following results were obtained: 1) cyclophosphamide did not alter (0.25 to 8h) percent radioactivity of 99m TcO04 in plasma or blood cells but increased the binding of 99m Tc-MDP to blood cells; 2) cyclophosphamide did not alter (o.25 to 8h) 6the binding of 99m TcO-4 in insoluble fraction of plasma and decreasde (1 to 4h) percent radioactivity of 99mTc-MDP in the insoluble fraction of plasma; 3) cyclophosphamide increased (0.25 to 4h) percent radioactivity of 99mTcO-4 in the insoluble fraction of blood cells but did not alter the binding of 99m Tc-MDP. Cyclophosphamide and/ or its methabolities modified the effective half-life of these radiopharmaceuticals (to 99TcO-4 was increased 2.3 to 3.4h and to 99mTc-MDP was decreased 3.3 to 2.1 h) and possibly increased the permeability of blood cells to 99m TcO-4


Asunto(s)
Animales , Femenino , Ratones , Células Sanguíneas/efectos de la radiación , Ciclofosfamida/farmacología , Plasma/efectos de la radiación
8.
Radiol. bras ; 24(2): 117-9, abr.-jun. 1991.
Artículo en Portugués | LILACS | ID: lil-100035

RESUMEN

A cintilografia esplênica seletiva pode ser o exame de eleiçäo quando há a necessidade de se estudar especificamente o baço. Para isso, descrevemos um método simplificado para marcaçäo in vitro de hemácias com tecnécio-99m com posterior desnaturaçäo térmica. Através dessa técnica é possível obter imagem cintilográfica esplênica com um número mais reduzido de manipulaçöes, quando comparada a métodos similares


Asunto(s)
Humanos , Femenino , Masculino , Bazo , Marcaje Isotópico/instrumentación , Tecnecio/administración & dosificación , Brasil
10.
Braz. j. med. biol. res ; 22(6): 787-9, June 1989. ilus
Artículo en Inglés | LILACS | ID: lil-75246

RESUMEN

The study of the labelling of planaria with 99mTc shows that the incorporation of radioactivity in this platyhelminth increases with an increase sin SnCl2 concentration from 0.13 to 1.3 micronM, reaching a plateau in the range of 1.3-130 micronM then decreasing with 1300 microng. At concentrations of 1.3 and 13 microngM SnCl2, a stronger binding of 99mTc was obtained. The biological viability of the labelled planaria was not altered when the described methodology was used. The advantage of this new labelling technique is that it is possible to obtain a platyhelminth preparation labelled with a radionuclide that is very cheap, is easily available and is a gamma emitter with a photon energy of 140 KeV


Asunto(s)
Planarias/fisiología , Tecnecio , Estaño/metabolismo
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