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1.
Colloids Surf B Biointerfaces ; 53(1): 29-36, 2006 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16959475

RESUMO

Water bound in human bone tissues healthy (sample S1) and affected by osteoporosis (sample S2) was investigated by using 1H NMR spectroscopy with layer-by-layer freezing-out of bulk and interfacial waters at T< 273 K. The 1H NMR spectra of the bound water include two signals which can be assigned to strongly associated typical water (chemical shift of the proton resonance at delta(H) approximately 5 ppm) and weakly associated water at delta(H) approximately 1.4 ppm. Approximately, half of the bound water is in the weakly associated state in S1. A fraction of similar water in S2 is smaller because of the structural difference of the studied samples. The pore size distribution of S2 (in aqueous medium) calculated using the cryoporometry method is characterized by much larger intensity of mesopores and macropores in comparison with that of S1. The total porosity and the surface area of the biostructures (accessible for water molecules and estimated on the basis of the cryoporometry data using a model of cylindrical pores) are larger for S2. Weakly polar chloroform-d has a significant influence on the organization of water in a spongy component of bone tissue. This effect depends on the porosity of the bone matrix and the amounts of CDCl3.


Assuntos
Osso e Ossos/química , Osso e Ossos/anatomia & histologia , Humanos , Espectroscopia de Ressonância Magnética/métodos , Osteoporose/fisiopatologia , Porosidade
2.
Colloids Surf B Biointerfaces ; 48(2): 167-75, 2006 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-16531020

RESUMO

Water bound in bone of rat tail vertebrae was investigated by 1H NMR spectroscopy at 210-300 K and by the thermally stimulated depolarization current (TSDC) method at 190-265 K. The 1H NMR spectra of water clusters were calculated by the GIAO method with the B3LYP/6-31G(d,p) basis set, and the solvent effects were analyzed by the HF/SM5.45/6-31G(d) method. The 1H NMR spectra of water in bone tissue include two signals that can be assigned to typical water (chemical shift of proton resonance deltaH=4-5 ppm) and unusual water (deltaH=1.2-1.7 ppm). According to the quantum chemical calculations, the latter can be attributed to water molecules without the hydrogen bonds through the hydrogen atoms, e.g., interacting with hydrophobic environment. An increase in the amount of water in bone leads to an increase in the amount of typical water, which is characterized by higher associativity (i.e., a larger average number of hydrogen bonds per molecule) and fills larger pores, cavities and pockets in bone tissue.


Assuntos
Osso e Ossos/química , Espectroscopia de Ressonância Magnética , Água/química , Algoritmos , Animais , Eletricidade , Congelamento , Temperatura Alta , Porosidade , Teoria Quântica , Ratos , Ratos Wistar , Coluna Vertebral/química , Eletricidade Estática , Cauda , Termodinâmica
3.
Biochim Biophys Acta ; 1624(1-3): 76-80, 2003 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-14642816

RESUMO

Growth and membrane polarization of Pseudomonas aeruginosa UG2 cells grown under randomized microgravity (RMG) and 1xg were measured in a high aspect ratio vessel (HARV) and also in batch cultures mixed at 12 and 150 rpm in Erlenmeyer shake flasks. Membrane polarization was measured using the fluorescent probe, 1,6-diphenyl-1,3,5-hexatriene (DPH). No differences were observed in the growth curves or membrane polarization values (about 0.300) under all three culture conditions. However, the net effect of RMG at the single cell level may be still unknown. It may be possible that RMG effects are species-dependent or bacterial cells with a small mass and volume may be near the threshold where RMG exerts a minimal effect.


Assuntos
Reatores Biológicos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Ausência de Peso , Polarização de Fluorescência , Corantes Fluorescentes , Fluidez de Membrana
4.
Eur J Obstet Gynecol Reprod Biol ; 98(1): 23-7, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11516795

RESUMO

OBJECTIVES: To investigate the concentrations of osteocalcin and collagen type I C-terminal telopeptides in pregnant women with pre-eclampsia. STUDY DESIGN: 26 patients with severe pre-eclampsia and 24 healthy pregnant women were included in the study. Serum concentrations of osteocalcin and C-telopeptides--degradation products of type I collagen were determined using the ELISA method. Statistical analysis was performed using Mann-Whitney U-test. RESULTS: In pre-eclamptic patients, the concentrations of osteocalcin and degradation products of collagen type I were significantly higher (P<0.005) when compared to healthy pregnant women. CONCLUSION: These results could suggest that there are alterations in bone metabolism in pregnant women with pre-eclampsia.


Assuntos
Colágeno/sangue , Osteocalcina/sangue , Peptídeos/sangue , Pré-Eclâmpsia/sangue , Adulto , Osso e Ossos/metabolismo , Colágeno Tipo I , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Gravidez , Valores de Referência
5.
Drugs Exp Clin Res ; 26(5-6): 321-5, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11345046

RESUMO

Ukrain, an acid alkaloid derivative from Chelidonium majus L., was administered intraperitoneally to intact and ovariectomized sexually mature female rats at doses of 7, 14 and 28 mg/kg once daily for 10 days, followed by 10-day break. This procedure was repeated five times. At the end of this Ukrain treatment (24 h after the last dose of the drug), the right femora of the rats were harvested and a three-point bending test until shaft failure was performed under standard conditions. Assembled data, including ultimate strength, ultimate energy at failure and ultimate displacement, were assessed. Strength and energy were adjusted to accommodate differences between groups in the end body weight. These results showed a decrease in adjusted bone strength of ovariectomized rats as compared to sham-operated animals. None of the three long-term doses of Ukrain (i.e., 7 mg/kg, 14 mg/kg and 28 mg/kg) significantly altered the bone strength when it was adjusted to the end body weight of the ovariectomized animals. Intact rats that received a 28 mg/kg dose of Ukrain demonstrated decrease of bone strength of 13.5% when it was adjusted to the end body weight.


Assuntos
Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Fêmur/fisiologia , Ovariectomia , Animais , Alcaloides de Berberina , Fenômenos Biomecânicos , Peso Corporal/efeitos dos fármacos , Feminino , Fêmur/efeitos dos fármacos , Fenantridinas , Ratos , Ratos Wistar
6.
Drugs Exp Clin Res ; 26(5-6): 327-31, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11345047

RESUMO

Ukrain, an acid alkaloid derivative of Chelidonium majus L., was administered intraperitoneally to ovariectomized and control sexually mature female rats at doses of 7, 14 and 28 mg/kg once daily for 10 days, followed by 10-day break. This procedure was repeated five times. At the end of the Ukrain treatment (24 h after the last dose of the drug) the right femora of the rats were harvested and the bone densitometric parameters of the whole bone and distal metaphysial and intertrochanteric subregions were assessed using the dual energy x-ray absorptiometry densitometric method. The results showed no apparent decrease in bone mineral density in groups of rats studied. A nearly significant (p = 0.08) decrease of bone mineral content was observed in ovariectomized rats treated with 14 mg/kg of Ukrain.


Assuntos
Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Densidade Óssea/efeitos dos fármacos , Fêmur/efeitos dos fármacos , Ovariectomia , Absorciometria de Fóton , Animais , Alcaloides de Berberina , Relação Dose-Resposta a Droga , Feminino , Fenantridinas , Ratos , Ratos Wistar
7.
Drugs Exp Clin Res ; 26(5-6): 333-6, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11345048

RESUMO

Ukrain, an acid alkaloid derivative of Chelidonium majus L., was administered intraperitoneally to ovariectomized and sexually mature female control rats at doses of 7, 14 and 28 mg/kg once daily for 10 days, followed by a 10-day break. This procedure was repeated five times. At the end of the long-term treatment with Ukrain (24 h after the last dose of the drug) the left femora of the rats were harvested. Dried bones were studied by electron paramagnetic resonance (EPR) method. Significant changes in the intensity of the native signal were observed within the groups (ANOVA, p = 0.0001); the lowest value was observed in the ovariectomized rats treated with 28 mg/kg of Ukrain (decrease of 40.8% compared to the ovariectomized group, p = 0.005). A significant increase in the intensity of the signal was observed in the intact 7 mg/kg Ukrain-treated group (34.7% compared to controls, p = 0.004).


Assuntos
Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Densidade Óssea/efeitos dos fármacos , Fêmur/efeitos dos fármacos , Ovariectomia , Alcaloides/administração & dosagem , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Alcaloides de Berberina , Relação Dose-Resposta a Droga , Espectroscopia de Ressonância de Spin Eletrônica , Feminino , Injeções Intraperitoneais , Tamanho do Órgão/efeitos dos fármacos , Fenantridinas , Ratos , Ratos Wistar
8.
J Endocrinol Invest ; 22(5): 323-6, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10401704

RESUMO

Young adult male Wistar rats (eight controls and ten experimental animals per group) were injected parenterally for 28 days: 1) cortisol or 2) cortisol and salmon calcitonin. Morphological changes of the stomach wall and enterochromaffin cells, stained immunocytochemically for serotonin, were assessed. In the group treated with cortisol superficial desquamation and erosions of the gastral mucosa were found. In this group the number of enterochromaffin cells was significantly decreased and low intensity of the immunocytochemical reaction of these cells was observed. In the cortisol-calcitonin-treated group there were no apparent changes of the gastral mucosa and the enterochromaffin cells presented a normal picture comparable to that of controls.


Assuntos
Calcitonina/farmacologia , Células Enterocromafins/efeitos dos fármacos , Mucosa Gástrica/citologia , Hidrocortisona/farmacologia , Animais , Calcitonina/administração & dosagem , Contagem de Células , Células Enterocromafins/química , Células Enterocromafins/citologia , Células Epiteliais/efeitos dos fármacos , Mucosa Gástrica/irrigação sanguínea , Mucosa Gástrica/efeitos dos fármacos , Hidrocortisona/administração & dosagem , Imuno-Histoquímica , Masculino , Ratos , Ratos Wistar , Serotonina/análise
9.
Gynecol Obstet Invest ; 46(3): 145-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9736792

RESUMO

Several observations suggest that endothelial cell dysfunction is a central pathophysiologic event of preeclampsia. Endothelin-1 (ET-1) is a vasoconstrictor peptide of the endotheliocyte and is increased in the sera of preeclamptic patients. The aim of this study was to investigate the possible regulatory mechanisms between ET-1 and nitric oxide (NO) production in cultured placental endotheliocytes. We report that endothelial cells of arterial placental blood vessels show a dysfunctional mechanism of negative feedback regulation of ET-1 production by cGMP or insufficient NO release in response to a stimulus in the form of an increasing ET-1 concentration.


Assuntos
Endotelina-1/metabolismo , Endotélio Vascular/metabolismo , Óxido Nítrico/metabolismo , Placenta/irrigação sanguínea , Pré-Eclâmpsia/metabolismo , Células Cultivadas , Meios de Cultura , GMP Cíclico/farmacologia , Endotélio Vascular/efeitos dos fármacos , Retroalimentação , Feminino , Humanos , Gravidez
10.
Drugs Exp Clin Res ; 24(5-6): 313-6, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10190094

RESUMO

Sexually mature but still growing female Wistar rats received i.p. injections of Ukrain (7, 14 or 28 mg/kg in a volume of 0.5 ml/100g) every other day for 10 days, followed by a 10-day break, and this procedure was performed five times. The control animals received the same volume of injected water. At the end of the experiment the rat right femora were harvested and the bone densitometric parameters of the entire bone, distal metaphyseal and basicervical subregions were assessed using the dual-energy X-ray absorptiometry (DXA) densitometric method. No significant changes were observed in the bone mineral density in experimental groups in comparison with control animals that received the vehicle. A slight decrease in the bone mineral content value was observed in the distal metaphyseal region in animals that were treated with the highest dose of Ukrain.


Assuntos
Alcaloides/toxicidade , Antineoplásicos/toxicidade , Densidade Óssea/efeitos dos fármacos , Animais , Alcaloides de Berberina , Relação Dose-Resposta a Droga , Feminino , Fenantridinas , Ratos , Ratos Wistar
11.
Drugs Exp Clin Res ; 24(5-6): 317-20, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10190095

RESUMO

Ukrain, thiophosphoric acid alkaloid derivative from Chelidonium majus L., was administered i.p. to ovariectomized rats in doses of 7, 14 and 28 mg/kg every other day for 10 days, followed by a 10-day break, and the procedure was performed five times. At the end of long-term treatment with Ukrain (24 h after the last dose of the drug) the rats' right femora were harvested and the bone densitometric parameters of the whole bone and distal metaphyseal and basicervical subregions were assessed using the dual-energy X-ray absorptiometry (DXA) densitometric method. The present results show a decrease in bone mineral density in groups of ovariectomized rats that received 7 mg/kg and 14 mg/kg of Ukrain versus untreated ovariectomized animals. Administration of Ukrain at a dose of 28 mg/kg did not significantly alter bone parameters of ovariectomized rats.


Assuntos
Alcaloides/toxicidade , Antineoplásicos/toxicidade , Densidade Óssea/efeitos dos fármacos , Animais , Alcaloides de Berberina , Relação Dose-Resposta a Droga , Feminino , Ovariectomia , Fenantridinas , Ratos , Ratos Wistar
13.
Drugs Exp Clin Res ; 22(3-5): 173-6, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8899324

RESUMO

Ukrain, thiophosphoric acid alkaloid derivatives from Chelidonium majus L. was administered intraperitoneally in a dose of 28 mg/kg (equivalent to 0.1 LD50) every other day for six months to female rats with ovariectomy-induced early osteoporosis. Administration of Ukrain was started on the second day after the surgical operation. At the end of the long-term treatment with Ukrain each rat was tested for the strength of both humeri and some parameters of rat femur were measured. The body weight of ovariectomized rats was also examined. The present results show that the decrease in the mechanical strength of the humeral bones and some changes in the femur caused by ovariectomy were prevented by the six-month treatment with Ukrain. However, in both ovariectomized groups and in ovariectomized rats pretreated with Ukrain an increase of body weight was observed.


Assuntos
Alcaloides/farmacologia , Antineoplásicos/farmacologia , Osso e Ossos/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Animais , Alcaloides de Berberina , Peso Corporal/efeitos dos fármacos , Esquema de Medicação , Feminino , Osteoporose/etiologia , Ovariectomia/efeitos adversos , Fenantridinas , Ratos , Ratos Wistar
14.
Drugs Exp Clin Res ; 22(3-5): 177-80, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8899325

RESUMO

Studies on Wistar rats have demonstrated that six months after ovariectomy no changes were observed in peripheral blood morphology other than a decreased leukocyte count. A similar effect was noted in the sham-operated group. The present results show that Ukrain treatment started on the second postoperative day and continued every other day for six months significantly increased leukocyte count in comparison with the untreated ovariectomized and sham-operated groups. The activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were also estimated in this study. In none of the groups studied was any change of ALT activity noted. The activity of AST was significantly increased in the sham-operated and untreated ovariectomized rats. After six-month treatment with Ukrain, the activity of this enzyme was significantly decreased in the serum of untreated ovariectomized rats. In rats pretreated with Ukrain some of the studied parameters of peripheral blood were similar to those of the control group.


Assuntos
Alcaloides/farmacologia , Osteoporose/sangue , Osteoporose/tratamento farmacológico , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Alcaloides de Berberina , Esquema de Medicação , Feminino , Contagem de Leucócitos/efeitos dos fármacos , Masculino , Osteoporose/etiologia , Ovariectomia/efeitos adversos , Fenantridinas , Ratos , Ratos Wistar
15.
Acta Histochem ; 96(4): 379-86, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7717042

RESUMO

Male young adult Wistar rats were treated parenterally with cortisol and cortisol combined with salmon calcitonin for 28 and 56 days and the stomach was investigated histologically as well as the G cells using immunohistochemistry. After 28 days of cortisol administration desquamation of the superficial layers of gastric mucosa was found and after 56 days ulcer-like changes developed and increased gastrin immunoreactivity was observed. Administration of high doses of salmon calcitonin together with cortisol resulted in a significant hypoplasia of G cells and prevented the pathological changes in the gastric mucosa.


Assuntos
Calcitonina/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Hidrocortisona/farmacologia , Animais , Calcitonina/administração & dosagem , Calcitonina/toxicidade , Modelos Animais de Doenças , Interações Medicamentosas , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Gastrinas/biossíntese , Hidrocortisona/administração & dosagem , Hidrocortisona/toxicidade , Imuno-Histoquímica , Injeções Intraperitoneais , Masculino , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamente
16.
Chir Narzadow Ruchu Ortop Pol ; 58(6): 463-9, 1993.
Artigo em Polonês | MEDLINE | ID: mdl-7555307

RESUMO

The method of the experiment has been presented. It was found, that after 8 weeks of hydrocortisonum hemisuccinatum administration, 20 mg per day in two doses the braking force decreased by 15 per cent. The calculation of the measurements at 150 g of animal body weight proved to be useful.


Assuntos
Anti-Inflamatórios/farmacologia , Fraturas do Colo Femoral/fisiopatologia , Colo do Fêmur/efeitos dos fármacos , Fraturas Espontâneas/fisiopatologia , Hidrocortisona/farmacologia , Animais , Fenômenos Biomecânicos , Ratos , Ratos Wistar , Resistência à Tração/efeitos dos fármacos
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