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1.
Braz J Med Biol Res ; 53(6): e9237, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32401926

RESUMO

We investigated changes in oxidative biomarkers in brain regions such as brainstem, cerebellum, and cerebral cortex of 3-, 6-, 18-, 24-, and 30-month-old rats. We also assessed the effects of low-intensity exercise on these biomarkers in these regions of 6-, 18-, and 24-month-old rats that started exercise on a treadmill at 3, 15, and 21 months of age, respectively. Radiographic images of the femur were taken for all rats. A total of 25 rats (age: twelve 6-, ten 18-, ten 24-, and three 30-month-old rats) were used. Lipid hydroperoxide levels increased in cerebellum at 18 months. Total antioxidant activity exhibited lowest values in brainstem at 3 months. Superoxide dismutase activity did not exhibit significant changes during aging. Total thiol content exhibited lowest values in brain regions of 24- and 30-month-old rats. Exercise reduced total thiol content in brainstem at 6 months, but no change occurred in other regions and other ages. Femur increased its length and width and cortical thickness with advancing age. No change occurred in medullary width. Radiolucency increased and sclerosis was found in cortical and medullary bone with advancing age. Exercise reduced radiolucency and medullary sclerosis. Therefore, aging differentially changed oxidative biomarkers in different brain regions and radiographic measures of the femur. Low-intensity exercise only ameliorated some radiographic measurements of femur. Since the present study possessed limitations (small number of rats per group), a beneficial effect of regular low-intensity exercise on oxidative markers in brain cannot be ruled out.


Assuntos
Envelhecimento/fisiologia , Encéfalo/metabolismo , Fêmur/diagnóstico por imagem , Peróxidos Lipídicos/análise , Estresse Oxidativo/fisiologia , Condicionamento Físico Animal/fisiologia , Envelhecimento/metabolismo , Animais , Biomarcadores/análise , Fêmur/química , Peroxidação de Lipídeos , Masculino , Oxirredução , Ratos , Ratos Wistar
2.
Braz. j. med. biol. res ; 53(6): e9237, 2020. tab, graf
Artigo em Inglês | LILACS, Coleciona SUS | ID: biblio-1132520

RESUMO

We investigated changes in oxidative biomarkers in brain regions such as brainstem, cerebellum, and cerebral cortex of 3-, 6-, 18-, 24-, and 30-month-old rats. We also assessed the effects of low-intensity exercise on these biomarkers in these regions of 6-, 18-, and 24-month-old rats that started exercise on a treadmill at 3, 15, and 21 months of age, respectively. Radiographic images of the femur were taken for all rats. A total of 25 rats (age: twelve 6-, ten 18-, ten 24-, and three 30-month-old rats) were used. Lipid hydroperoxide levels increased in cerebellum at 18 months. Total antioxidant activity exhibited lowest values in brainstem at 3 months. Superoxide dismutase activity did not exhibit significant changes during aging. Total thiol content exhibited lowest values in brain regions of 24- and 30-month-old rats. Exercise reduced total thiol content in brainstem at 6 months, but no change occurred in other regions and other ages. Femur increased its length and width and cortical thickness with advancing age. No change occurred in medullary width. Radiolucency increased and sclerosis was found in cortical and medullary bone with advancing age. Exercise reduced radiolucency and medullary sclerosis. Therefore, aging differentially changed oxidative biomarkers in different brain regions and radiographic measures of the femur. Low-intensity exercise only ameliorated some radiographic measurements of femur. Since the present study possessed limitations (small number of rats per group), a beneficial effect of regular low-intensity exercise on oxidative markers in brain cannot be ruled out.


Assuntos
Animais , Masculino , Ratos , Condicionamento Físico Animal/fisiologia , Encéfalo/metabolismo , Envelhecimento/fisiologia , Estresse Oxidativo/fisiologia , Fêmur/diagnóstico por imagem , Peróxidos Lipídicos/análise , Oxirredução , Envelhecimento/metabolismo , Biomarcadores/análise , Peroxidação de Lipídeos , Ratos Wistar , Fêmur/química
3.
J Chromatogr A ; 914(1-2): 325-30, 2001 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-11358227

RESUMO

Artifact-free, high-resolution matrix-assisted laser desorption ionization (MALDI) time-of-flight mass spectra have been obtained for the labile, single-isomer, tert.-butyldimethylsilyl ether derivatives of alpha-, beta- and gamma-cyclodextrins by optimizing the MALDI sample preparation method. 2,5-Dihydroxybenzoic acid, a 3:1 mixture of 2,5-dihydroxybenzoic acid and 1-hydroxyisoquinoline, and 2,4,6-trihydroxyacetophenone were investigated as MALDI matrices with methanol and acetonitrile as matrix solvents. Partial-to-complete loss of the tert.-butyldimethylsilyl groups was observed when the commonly used 2,5-dihydroxybenzoic acid was the MALDI matrix and/or methanol was the solvent, both with and without trifluoroacetic acid as additive. Loss of the labile tert.-butyldimethylsilyl groups was avoided with 2,4,6-trihydroxyacetophenone as MALDI matrix and acetonitrile as matrix solvent. Good ion intensities were achieved for the (M+Na)+ and (M+K)+ quasimolecular ions in the positive-ion mode. Minor byproducts were observed in some of the samples and the information was used to aid the optimization of the synthetic work.


Assuntos
Ciclodextrinas/síntese química , Eletroforese Capilar/métodos , Compostos de Organossilício/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Artefatos , Éteres/química , Estereoisomerismo
5.
Pharmazie ; 53(11): 764-6, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9853358

RESUMO

Mono- and bicyclic isothiazol-3(2 H)-one 1,1-dioxides and tetrahydrosaccharines 7 were produced by oxidation of the 3-unsubstituted isothiazoles 6. Determination of cross reactivity indicates high values for Compounds 7e and 7l.


Assuntos
Óxidos S-Cíclicos/química , Sacarina/análise , Tiazóis/química , Animais , Especificidade de Anticorpos , Reações Cruzadas , Óxidos S-Cíclicos/imunologia , Ensaio de Imunoadsorção Enzimática , Cabras/imunologia , Tiazóis/imunologia
6.
Plast Reconstr Surg ; 102(5): 1537-43, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9774008

RESUMO

Microsurgical skin flaps raised from various body regions show differences in vascular architecture, cutaneous capillary density, and skin perfusion. Therefore, it can be expected that oxygenation of the skin is different at the various free flap donor sites. To determine the cutaneous oxygen supply, intracapillary hemoglobin oxygenation was measured on the donor sites of the radial forearm flap, scapula, latissimus dorsi, rectus abdominis, anterolateral thigh, and osteocutaneous fibula flap on 50 healthy subjects (25 men and 25 women aged 20 to 40 years). Measurements were performed noninvasively with the Erlangen Microlightguide Spectrophotometer (EMPHO) on skin areas of 6 x 8 cm in each region under resting conditions. The hemoglobin oxygenation of the skin in all donor regions varied between a maximum of 43.94 to 58.94 percent in the scapula region and a minimum of 13.89 to 29.45 percent in the lateral calf. High oxygenation values were also found on the skin over the latissimus dorsi muscle (34.56 to 48.45 percent), followed by the distal volar forearm (29.78 to 40.30 percent), whereas paraumbilical skin and the donor sites of the lower extremities were less oxygenated. By using the Wilcoxon test, significant differences were found between all donor regions except for the anterolateral thigh and lateral calf (p = 0.05). There were no gender-specific differences. From these results, it is concluded that, on young healthy subjects, regional oxygen supply on different free flap donor sites varies significantly. This finding must be considered in the interpretation of intracutaneous or transcutaneous PO2 measurements for flap monitoring.


Assuntos
Hemoglobinas/metabolismo , Pele/metabolismo , Retalhos Cirúrgicos/fisiologia , Adulto , Monitorização Transcutânea dos Gases Sanguíneos , Feminino , Humanos , Masculino
7.
S D J Med ; 51(3): 85-7, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9550927

RESUMO

A 41-year-old woman underwent a successful stapedectomy for relief of conductive hearing loss due to otosclerosis. Post-operatively, she developed persistent symptoms of benign paroxysmal positional vertigo (BPPV). Eight weeks later, a canalith repositioning procedure was performed in the office, with immediate complete resolution of her vertigo. Anatomic and pathophysiologic implications of these observations will be discussed.


Assuntos
Cirurgia do Estribo/efeitos adversos , Vertigem/etiologia , Vertigem/terapia , Adulto , Feminino , Movimentos da Cabeça , Humanos , Postura , Sáculo e Utrículo , Canais Semicirculares
8.
Artigo em Inglês | MEDLINE | ID: mdl-2875556

RESUMO

In vivo studies on the effect of two stereoisomeric 7,22-dihydroxycholesterols on tumor development were conducted in the Charles Huggins animal cancer model (DMBA-induced mammary cancer in the Sprague-Dawley female rat). Three groups of DMBA-treated animals were fed a 9:1 mixture of (22R)-cholest-5-ene-3 beta,7 beta,22-triol and (22R)-cholest-5-ene-3 beta,7 alpha,22-triol in the drinking water in a calculated dose of 250 micrograms per animal per day. One group (A) received the sterols throughout the experimental period of 35 weeks, another group (B) during the first 12 weeks only, and a third group (C) only during weeks 13 through 35 after DMBA injection. Tumor rates and tumor yields were calculated, and statistical assessment by accepted methods demonstrated a very significant inhibitory effect on tumor development in Groups A and B, as compared with Group C. The results indicate a growth-inhibitory effect during the induction period of carcinoma development. The influence on neoplastic growth of (22R)-cholest-5-ene-3 beta,7 alpha,22-triol, (22R)-cholest-5-ene-3 beta,7 beta,22-triol, and (22R)-cholest-5-ene-3 beta,22-diol-7-one was examined in suspension cultures of Ehrlich ascites tumor cells. The 7 alpha-hydroxy compound proved to be ineffective, whereas the latter two substances displayed a strong cytotoxic effect.


Assuntos
Hidroxicolesteróis/farmacologia , Neoplasias Mamárias Experimentais/induzido quimicamente , 9,10-Dimetil-1,2-benzantraceno/antagonistas & inibidores , Animais , Antineoplásicos , Carcinoma de Ehrlich/patologia , Sobrevivência Celular/efeitos dos fármacos , Feminino , Ratos , Estereoisomerismo
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