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1.
Rev. ciênc. farm. básica apl ; Rev. ciênc. farm. básica apl;31(1)2010.
Artigo em Português | LILACS | ID: lil-560261

RESUMO

A adesão ao tratamento farmacológico em doenças crônicas como a hipertensão arterial, é fundamental para o controle, prevenção de complicações e diminuição da mortalidade. Identificar os fatores que levam a não adesão ao programa de controle de hipertensão arterial, em Unidades Básicas de Saúde de Campo Grande, MS e produzir um modelo de predição desta condição foi o objetivo do presente estudo. Utilizou-se o método de caso-controle, aninhado a coorte de pacientes cadastrados no programa, no período de 2002 a 2005. Foi utilizada regressão logística tendo como variável-resposta ?adesão ao programa?. As associações significativas identificadas na análise univariada foram: características socioeconômicas, da doença, do tratamento e as relacionadas ao programa. Para prever a adesão, mantiveram-se no modelo as seguintes variáveis: dificuldade em ir ao programa, renda familiar, presença de diabetes, escolaridade e viver com companheiro. Com base no modelo, a probabilidade do paciente ser classificado corretamente como aderente, é de aproximadamente, 80% e como não aderente, 67%. O modelo identifica precocemente, pacientes vulneráveis à não adesão ao programa propiciando que este institua medidas voltadas aos prováveis, não aderentes.


Adherence to the pharmacological treatment of chronic diseases such as arterial hypertension is decisive in their control, in preventing complications, and in decreasing mortality rates. To identify factors that led patients to drop out of an arterial hypertension control program available at local district clinics of the government-run National Health Service in Campo Grande, MS, Brazil, and to design a model to predict adherence. A nested case?control study was conducted on subjects selected from within a cohort of patients enrolled in the above program, from 2002 to 2005. Binary logistic regression was used, with ?adherence to program? as the binary response variable. Data were subjected to logistic regression analysis to generate a model capable of predicting adherence. Factors identified: difficulty in going to the venue where the program was available, family income, presence of diabetes, level of education and living with a partner. When the logistic regression model was used, the probability of a patient being correctly classified as adherent and nonadherent was approximately 80% and 67%, respectively. The model enables early identification of patients prone to nonadherence to the control program, thus making it possible to implement measures directed at potentially nonadherent participants.


Assuntos
Humanos , Planos e Programas de Saúde , Hipertensão/prevenção & controle
2.
Br J Pharmacol ; 158(2): 580-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19663883

RESUMO

BACKGROUND AND PURPOSE: Adding spironolactone to standard therapy in heart failure reduces morbidity and mortality, but the underlying mechanisms are not fully understood. We analysed the effect of canrenone, the major active metabolite of spironolactone, on myocardial contractility and intracellular calcium homeostasis. EXPERIMENTAL APPROACH: Left ventricular papillary muscles and cardiomyocytes were isolated from male Wistar rats. Contractility of papillary muscles was assessed with force transducers, Ca(2+) transients by fluorescence and Ca(2+) fluxes by electrophysiological techniques. KEY RESULTS: Canrenone (300-600 micromol L(-1)) reduced developed tension, maximum rate of tension increase and maximum rate of tension decay of papillary muscles. In cardiomyocytes, canrenone (50 micromol L(-1)) reduced cell shortening and L-type Ca(2+) channel current, whereas steady-state activation and inactivation, and reactivation curves were unchanged. Canrenone also decreased the Ca(2+) content of the sarcoplasmic reticulum, intracellular Ca(2+) transient amplitude and intracellular diastolic Ca(2+) concentration. However, the time course of [Ca(2+)](i) decline during transients evoked by caffeine was not affected by canrenone. CONCLUSION AND IMPLICATIONS: Canrenone reduced L-type Ca(2+) channel current, amplitude of intracellular Ca(2+) transients and Ca(2+) content of sarcoplasmic reticulum in cardiomyocytes. These changes are likely to underlie the negative inotropic effect of canrenone.


Assuntos
Canais de Cálcio Tipo L/efeitos dos fármacos , Cálcio/metabolismo , Canrenona/farmacologia , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Animais , Cafeína/farmacologia , Canais de Cálcio Tipo L/metabolismo , Canrenona/administração & dosagem , Relação Dose-Resposta a Droga , Homeostase , Masculino , Antagonistas de Receptores de Mineralocorticoides/administração & dosagem , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Músculos Papilares/efeitos dos fármacos , Músculos Papilares/metabolismo , Ratos , Ratos Wistar , Retículo Sarcoplasmático/metabolismo , Espironolactona/metabolismo
3.
Braz J Med Biol Res ; 39(5): 611-4, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16648898

RESUMO

In a comparative study of erythrocyte metabolism of vertebrates, the specific activity of glucose-6-phosphate dehydrogenase (G6PD) of the Brazilian opossum Didelphis marsupialis in a hemolysate was shown to be high, 207 +/- 38 IU g-1 Hb-1 min-1 at 37 degrees C, compared to the human erythrocyte activity of 12 +/- 2 IU g-1 Hb-1 min-1 at 37 degrees C. The apparent high specific activity of the mixture led us to investigate the physicochemical properties of the opossum enzyme. We report that reduced glutathione (GSH) in the erythrocytes was only 50% higher than in human erythrocytes, a value lower than expected from the high G6PD activity since GSH is maintained in a reduced state by G6PD activity. The molecular mass, determined by G-200 Sephadex column chromatography at pH 8.0, was 265 kDa, which is essentially the same as that of human G6PD (260 kDa). The Michaelis-Menten constants (Km: 55 microM) for glucose-6-phosphate and nicotinamide adenine dinucleotide phosphate (Km: 3.3 microM) were similar to those of the human enzyme (Km: 50-70 and Km: 2.9-4.4, respectively). A 450-fold purification of the opossum enzyme was achieved and the specific activity of the purified enzyme, 90 IU/mg protein, was actually lower than the 150 IU/mg protein observed for human G6PD. We conclude that G6PD after purification from the hemolysate of D. marsupialis does not have a high specific activity. Thus, it is quite probable that the red cell hyperactivity reported may be explained by increased synthesis of G6PD molecules per unit of hemoglobin or to reduced inactivation in the RBC hemolysate.


Assuntos
Didelphis/sangue , Eritrócitos/enzimologia , Glucosefosfato Desidrogenase/sangue , Glutationa/metabolismo , Animais , Brasil , Cromatografia , Eritrócitos/química , Glucosefosfato Desidrogenase/isolamento & purificação , Oxirredução
4.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;39(5): 611-614, May 2006. ilus, tab
Artigo em Inglês | LILACS | ID: lil-425795

RESUMO

In a comparative study of erythrocyte metabolism of vertebrates, the specific activity of glucose-6-phosphate dehydrogenase (G6PD) of the Brazilian opossum Didelphis marsupialis in a hemolysate was shown to be high, 207 ± 38 IU g-1 Hb-1 min-1 at 37°C, compared to the human erythrocyte activity of 12 ± 2 IU g-1 Hb-1 min-1 at 37°C. The apparent high specific activity of the mixture led us to investigate the physicochemical properties of the opossum enzyme. We report that reduced glutathione (GSH) in the erythrocytes was only 50 percent higher than in human erythrocytes, a value lower than expected from the high G6PD activity since GSH is maintained in a reduced state by G6PD activity. The molecular mass, determined by G-200 Sephadex column chromatography at pH 8.0, was 265 kDa, which is essentially the same as that of human G6PD (260 kDa). The Michaelis-Menten constants (Km: 55 æM) for glucose-6-phosphate and nicotinamide adenine dinucleotide phosphate (Km: 3.3 æM) were similar to those of the human enzyme (Km: 50-70 and Km: 2.9-4.4, respectively). A 450-fold purification of the opossum enzyme was achieved and the specific activity of the purified enzyme, 90 IU/mg protein, was actually lower than the 150 IU/mg protein observed for human G6PD. We conclude that G6PD after purification from the hemolysate of D. marsupialis does not have a high specific activity. Thus, it is quite probable that the red cell hyperactivity reported may be explained by increased synthesis of G6PD molecules per unit of hemoglobin or to reduced inactivation in the RBC hemolysate.


Assuntos
Animais , Didelphis/sangue , Eritrócitos/enzimologia , Glucosefosfato Desidrogenase/sangue , Glutationa/metabolismo , Brasil , Cromatografia , Eritrócitos/química , Glucosefosfato Desidrogenase/isolamento & purificação , Oxirredução
5.
J Fluoresc ; 14(6): 711-22, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15649023

RESUMO

Fura-2 is one of the most used fluorophore for measuring intracellular calcium concentration ([Ca2+]i). In mouse bone marrow cell suspensions ATP produces a biphasic effect: till 1 mM, ATP produces increases in [Ca2+]i; from 1 mM on an increase is observed, that is followed by the decrease in the 340/380 nm ratio (R340/380). At high ATP (4 mM) concentration fura-2 leaked from loaded bone marrow cell suspensions. We observed that ATP decreases fluorescence in the absorption and excitation spectra of fura-2, consequently the emitted one is decreased including the isobestic point (360 nm). ATP analogs: BzATP, ATPyS and UTP, but not alphabetaATP, ADP or AMP, promote decrease of fluorescence in the isobestic point of fura-2. The physical/chemical process that reduces the absorption and excitation of fura-2 by ATP is unknown. The P2X7 inhibitors, Mg2+ (5 mM), OxATP (300 microM) and Brilliant Blue (100 nM), blocked the efflux of fura-2 and ATP-induced R340/380 decrease. The J774 cell line and mononuclear cells with a higher expression of P2X7 receptors show the same decrease in R340/380 as that induced by ATP. In the HL-60 cell line, myeloid cells and erythroblasts extracted from bone marrow, such effect does not occur. It is concluded that the use of the fluorescent Ca2+ indicator fura-2 does not allow the correct measurement of [Ca2+]i in these cells in the presence of a higher concentration of ATP which activated the P2X7 receptor.


Assuntos
Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/metabolismo , Células da Medula Óssea/metabolismo , Corantes Fluorescentes/metabolismo , Fura-2/metabolismo , Receptores Purinérgicos P2/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Células da Medula Óssea/efeitos dos fármacos , Cálcio/metabolismo , Cálcio/farmacologia , Linhagem Celular , Feminino , Células HL-60 , Humanos , Técnicas In Vitro , Magnésio/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Antagonistas do Receptor Purinérgico P2 , Receptores Purinérgicos P2X7 , Corantes de Rosanilina/farmacologia , Espectrometria de Fluorescência
6.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;v. 33(11): 1313-nov. 2000. tab
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IALPROD, Sec. Est. Saúde SP, SESSP-IALACERVO | ID: biblio-1061618

RESUMO

Fetal hemoglobin was measured in HIV 1/2 patients under treatment with combined therapy (zidovudine and a protease inhbitor). A total of 143 patientes and 103 normal individual were investigated by the quantitative method of Betke and the semi-quantitative acid elution method of Keihauer. In the normal person, hemoglobin F makes up less than.


Assuntos
HIV-1 , HIV , HIV-2 , Hemoglobina Fetal , Hemoglobinas , Zidovudina
7.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;33(11): 1313-5, Nov. 2000. tab
Artigo em Inglês | LILACS | ID: lil-273208

RESUMO

Fetal hemoglobin was measured in HIV1/2 patients under treatment with combined therapy (zidovudine and a protease inhibitor). A total of 143 patients and 103 normal individuals were investigated by the quantitative method of Betke and the semi-quantitative acid elution method of Kleihauer. In the normal person, hemoglobin F makes up less than 1 percent and an increase higher than 1.5 percent was observed in 21.4 percent of HIV patients by the method of Betke and in 24.8 percent of HIV-infected patients by the method of Kleihauer. The quantitative biochemical method of Betke showed that the populations were significantly different (two-tailed Mann-Whitney test). The reason for this hemoglobin F increase might be ascribed to the effect of zidovudine or to direct viral action on gamma chain expression. The finding of a higher F cell frequency indicated by the method of Kleihauer rather suggests that there is an increased F cell clone proliferation rather than an increase in hemoglobin F level in every cell


Assuntos
Humanos , Hemoglobina Fetal/análise , Infecções por HIV/sangue , Fármacos Anti-HIV/uso terapêutico , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Células Precursoras Eritroides/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , Estatísticas não Paramétricas , Zidovudina/uso terapêutico
8.
Braz J Med Biol Res ; 33(11): 1313-5, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11050661

RESUMO

Fetal hemoglobin was measured in HIV1/2 patients under treatment with combined therapy (zidovudine and a protease inhibitor). A total of 143 patients and 103 normal individuals were investigated by the quantitative method of Betke and the semi-quantitative acid elution method of Kleihauer. In the normal person, hemoglobin F makes up less than 1% and an increase higher than 1.5% was observed in 21.4% of HIV patients by the method of Betke and in 24.8% of HIV-infected patients by the method of Kleihauer. The quantitative biochemical method of Betke showed that the populations were significantly different (two-tailed Mann-Whitney test). The reason for this hemoglobin F increase might be ascribed to the effect of zidovudine or to direct viral action on gamma chain expression. The finding of a higher F cell frequency indicated by the method of Kleihauer rather suggests that there is an increased F cell clone proliferation rather than an increase in hemoglobin F level in every cell.


Assuntos
Hemoglobina Fetal/análise , Infecções por HIV/sangue , Fármacos Anti-HIV/uso terapêutico , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Células Precursoras Eritroides/efeitos dos fármacos , Hemoglobina Fetal/metabolismo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , Inibidores da Protease de HIV/uso terapêutico , Humanos , Estatísticas não Paramétricas , Zidovudina/uso terapêutico
9.
Exp Nephrol ; 6(3): 245-52, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9639040

RESUMO

The effects of recombinant human erythropoietin (rHuEPO)-induced polycythemia on renal function and glomerular hemodynamics were evaluated in Munich-Wistar rats (MW+EPO) before and after infusion of indomethacin; the rHuEPO effects on total renal function were also evaluated in 5/6 nephrectomized (CRF) MW and spontaneously hypertensive rats (MW-CRF+EPO and SHR-CRF+EPO, respectively). In normal MW rats, rHuEPO (300 IU/kg BW, 3 x /week, during 2 weeks) induced elevation in MAP, with maintenance of GFR, paralleled by superficial vasodilatation and elevation in SNGFR, suggesting cortical blood redistribution. These hemodynamic alterations induced by rHuEPO were blunted by indomethacin, suggesting a participation of the vasodilator prostaglandins in the renal compensatory mechanism of polycythemia. Elevation in MAP and reduction in GFR occurred in the MW-CRF+EPO group compared with the group receiving vehicle. In contrast, the SHR-CRF+EPO presented a reduction in MAP and maintenance of GFR, suggesting different rHuEPO effects depending on previous renal function and/or hypertensive state.


Assuntos
Eritropoetina/farmacologia , Nefrectomia , Policitemia/induzido quimicamente , Circulação Renal/fisiologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Indometacina/farmacologia , Glomérulos Renais/irrigação sanguínea , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/fisiologia , Masculino , Policitemia/fisiopatologia , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , Proteínas Recombinantes , Circulação Renal/efeitos dos fármacos , Vasodilatação/fisiologia
10.
Biochem J ; 330 ( Pt 1): 505-11, 1998 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9461549

RESUMO

Mammalian cell invasion assays, using metacyclic trypomastigotes of Trypanosoma cruzi G and CL strains, showed that the CL strain enters target cells in several-fold higher numbers as compared with the G strain. Analysis of expression of surface glycoproteins in metacyclic forms of the two strains by iodination, immunoprecipitation and FACS, revealed that gp90, undetectable in the CL strain, is one of the major surface molecules in the G strain, that expression of gp82 is comparable in both strains and that gp35/50 is expressed at lower levels in the CL strain. Purified gp90 and gp35/50 bound more efficiently than gp82 to cultured HeLa cells. However, the intensity of the Ca2+ response triggered in HeLa cells by gp82 was significantly higher than that induced by gp35/50 or gp90. Most of the Ca2+ signalling activity of the metacyclic extract towards HeLa cells was due to gp82 and was inhibitable by gp82-specific monoclonal antibody 3F6. Ca2+ mobilization was also triggered in metacyclic trypomastigotes by host-cell components; it was mainly gp82-mediated and more intense in the CL than in the G strain. We propose that expression of gp90 and gp35/50 at high levels impairs binding of metacyclic forms to host cells through productive gp82-mediated interaction, which leads to the target-cell and parasite Ca2+ mobilization required for invasion. Analysis of metacyclic forms of eight additional T. cruzi strains corroborated the inverse correlation between infectivity and expression of gp90 and gp35/50.


Assuntos
Cálcio/fisiologia , Proteínas de Protozoários/fisiologia , Trypanosoma cruzi/patogenicidade , Animais , Anticorpos Antiprotozoários/fisiologia , Antígenos de Protozoários/fisiologia , Antígenos de Superfície/fisiologia , Moléculas de Adesão Celular/fisiologia , Glicoproteínas/fisiologia , Peso Molecular , Proteínas de Protozoários/química , Glicoproteínas Variantes de Superfície de Trypanosoma/fisiologia
11.
Eur J Pharmacol ; 342(1): 119-22, 1998 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-9544800

RESUMO

In rat stomach fundus, contractions induced by Ca2+ (1.8 mM) were strikingly potentiated by thapsigargin. This potentiation was partially inhibited by the blockers of Ca2+ release activated channels (CRACs), miconazole and SK&F96365 ([1-[beta-[3-(4-methoxyphenyl)propoxy]-4-methoxyphenethyl]-1H-imidazole, HCL]) and slightly blocked by the antagonist of calcium voltage-operated channels (VOCs), isradipine. In dissociated cells in a 0Ca solution, thapsigargin potentiated the increase in intracellular calcium after reintroduction of Ca2+. This potentiation was partially reduced by the CRAC blockers, but not by the VOC blockers. This data suggests that calcium influx increased due to the depletion of intracellular calcium by thapsigargin and that this influx occurs predominantly through CRACs.


Assuntos
Canais de Cálcio/metabolismo , Cálcio/metabolismo , Músculo Liso/metabolismo , Animais , Fundo Gástrico/citologia , Fundo Gástrico/metabolismo , Técnicas In Vitro , Contração Muscular/fisiologia , Músculo Liso/citologia , Ratos , Ratos Wistar
12.
Artif Organs ; 21(10): 1136-7, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9335375

RESUMO

This paper describes a device used to measure the isometric forces generated during electrical stimulation of the canine latissimus dorsi muscle in vivo with a preserved neurovascular supply. This device uses 2 strain gauge force sensors linked to a movable alignment frame to which the muscle is attached. The muscle length is controlled by the application of known weights to the system. The device has a frequency of response of 17.5 Hz and compliance of approximately 0.1 mm N(-1), and its experimental performance was tested in the anesthetized mongrel dog.


Assuntos
Contração Isométrica/fisiologia , Músculo Esquelético/fisiologia , Animais , Cardiomioplastia , Cães , Estimulação Elétrica , Equipamentos e Provisões
14.
Kidney Int ; 51(1): 87-93, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8995721

RESUMO

To evaluate functional alterations of mesangial cells induced by diabetes (DMC), we observed the changes of cytosolic calcium ([Ca]i) in response to the vasoconstrictor agonists angiotensin II (Ang II) and norepinephrine (NOR). DMC were obtained from rats with streptozotocin-induced diabetes, cultured in normal medium and identified as mesangial cells (MC) in the third subculture. [Ca]i was measured using fura-2 as a fluorophore. Basal calcium levels (60 to 80 nM) in DMC were not different from control mesangial cells (CMC). The high glucose (30 mM) medium concentration reduced the response of CMC and DMC to Ang II and NOR. This was not an osmotic effect since mannitol did not alter these responses. When DMC were stimulated with Ang II, a desensitized response was always observed, with a transient variation of [Ca]i (N = 6, P < 0.05). In contrast, a non-desensitized response with a sustained pattern of [Ca]i increases was obtained in NOR-stimulated DMC. Therefore, the present results suggest that DMC show a modified response to stimulation of the Ang II receptor, which is expressed phenotypically in culture by desensitization. Furthermore, these alterations induced by diabetes environment in MC in vivo were maintained in vitro despite a long period (approximately 5 months) in which the cells were grown in normal culture medium.


Assuntos
Angiotensina II/farmacologia , Cálcio/metabolismo , Mesângio Glomerular/citologia , Norepinefrina/farmacologia , Vasoconstritores/farmacologia , Animais , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Citosol/metabolismo , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/metabolismo , Relação Dose-Resposta a Droga , Mesângio Glomerular/efeitos dos fármacos , Mesângio Glomerular/metabolismo , Glucose/farmacologia , Masculino , Ratos , Ratos Wistar
15.
Mol Biochem Parasitol ; 84(1): 57-67, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9041521

RESUMO

The 35/50 kDa mucin-like surface glycoprotein (gp35/50) of Trypanosoma cruzi metacyclic trypomastigotes has been implicated in mammalian cell invasion. In this study we investigated whether the sialyl residues of gp35/50 are required for interaction of parasites with target cells. After treatment with bacterial neuraminidase, the metacyclic forms (G strain) remained reactive with the monoclonal antibody (mAb) 10D8 but lost their reactivity with mAb 3C9, that recognizes sialic acid-containing epitopes on gp35/50, and entered HeLa cells in significantly higher numbers as compared to untreated controls. Resialylation of gp35/50, by incubation of parasites with T. cruzi trans-sialidase and sialyl lactose, restored the reactivity with mAb 3C9 as well as the affinity for sialic acid specific lectin. Accordingly, the rate of invasion of resialylated parasites was reduced to levels similar to those observed before desialylation. Purified G strain gp35/50, desialylated by neuraminidase treatment, bound to HeLa cells more than its sialylated counterpart. The Ca2+ signaling activity, which has been associated with cell invasion, was also determined by measuring the cytosolic Ca2+ concentration ([Ca2+]i), in HeLa cells upon interaction with sonicated extracts from untreated or neuraminidase-treated parasites, or with purified gp35/50 in its sialylated or desialylated form. Consistent with the results of cell invasion assay, the desialylated parasite preparations, as well as the sialic acid free gp35/50, induced an average elevation in [Ca2+]i significantly higher than that triggered by untreated controls. None of these effects, namely the increase in infectivity and Ca2+ signaling activity, was observed with neuraminidase-treated CL strain metacyclic trypomastigotes, which express a variant form of sialic acid gp35/50 molecule that is not recognized by mAb 10D8 and apparently is not involved in target cell invasion.


Assuntos
Glicoproteínas de Membrana/isolamento & purificação , Mucinas/isolamento & purificação , Proteínas de Protozoários/isolamento & purificação , Trypanosoma cruzi/química , Animais , Cálcio/metabolismo , Células HeLa/parasitologia , Humanos , Ácido N-Acetilneuramínico , Neuraminidase/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/imunologia
17.
Kidney Int ; 48(1): 56-64, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7564092

RESUMO

FK 506 is a new immunosuppressive drug that, like cyclosporine A (CsA), presents nephrotoxicity. Glomerular hemodynamic studies showed that acute FK 506 infusion (N = 9, 3 mg/kg body wt, i.v. in bolus) caused a 57% reduction in glomerular filtration rate (GFR) (0.74 +/- 0.03 to 0.32 +/- 0.02 ml/min, P < 0.05) and a 40% reduction in single nephron glomerular filtration rate (SNGFR; 43.0 +/- 5.2 to 26.0 +/- 2.5 nl/min, P < 0.05) due to a 25% reduction in glomerular plasma flow rate (QA) (133.4 +/- 19.8 to 99.8 +/- 12.0 nl/min) and a 22% reduction in glomerular ultrafiltration coefficient (Kf; 0.1009 +/- 0.0203 to 0.0790 +/- 0.0130 nl/sec. mm Hg). After 10 days of FK treatment (N = 8, 0.6 mg/kg body wt, i.p.), we observed a reduction of 23% in GFR (0.97 +/- 0.02 to 0.75 +/- 0.04 ml/min, P < 0.05) and of 23% in SNGFR (37.9 +/- 3.0 to 29.1 +/- 1.9 nl/min, P < 0.05) due to a 42% reduction in Kf (0.1486 +/- 0.0101 to 0.0870 +/- 0.0110 nl/sec.mm Hg, P < 0.05) and a 38% reduction in QA (117.6 +/- 10.2 to 73.5 +/- 6.1 nl/min, P < 0.05). The latter was consequent to the increment of 72% in total arteriolar resistance (RT) (3.1 +/- 0.2 to 5.2 +/- 0.5 +/- 0.5 10(10).dyn.sec.cm-5, P < 0.05). Thus, the pattern of FK 506 effect on glomerular hemodynamics was similar in both acute and chronic treatments.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Mesângio Glomerular/efeitos dos fármacos , Glomérulos Renais/efeitos dos fármacos , Tacrolimo/farmacologia , Animais , Cálcio/metabolismo , Células Cultivadas/efeitos dos fármacos , Taxa de Filtração Glomerular , Mesângio Glomerular/citologia , Hemodinâmica/efeitos dos fármacos , Glomérulos Renais/irrigação sanguínea , Masculino , Microcirculação/efeitos dos fármacos , Ratos , Ratos Wistar , Fluxo Plasmático Renal
18.
Braz J Med Biol Res ; 28(5): 609-13, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-8555983

RESUMO

The effect of angiotensin II (ANG II) and atrial natriuretic peptide (ANP) on intracellular free calcium concentration [Ca2+]i was investigated in Mandin-Darby canine kidney (MDCK) cells in culture. Changes in [Ca2+]i were monitored fluorometrically with the Ca(2+)-sensitive probe fura-2/AM at 37 degrees C using a Perkin-Elmer LS-5 spectrofluorimeter (excitation 340/380 nm, slit 3 nm; emission 520 nm, slit 10 nm). MDCK cells exhibited a mean baseline [Ca2+]i of 98 +/- 10 nM. The addition of increasing concentrations of ANG II (1 pM to 1 microM) to the cell suspension led to a progressive increase in [Ca2+]i to 2-3 times basal levels. In contrast, addition of 1 microM ANP to the cell suspension led to a very rapid 60% decrease in [Ca2+]i. The addition of 1 pM to 1 microM ANG II immediately after 1 microM ANP caused an increase in [Ca2+]i which never exceeded the basal level in the absence of ANP. The data indicate that ANG II increases cell [Ca2+]i, as expected, and provide the new observation that ANP reduces [Ca2+]i in these cells. Furthermore, ANP reduces the increase in [Ca2+]i elicited by ANG II, thus modulating the effect of ANG II on [Ca2+]i.


Assuntos
Angiotensina II/farmacologia , Fator Natriurético Atrial/farmacologia , Cálcio/metabolismo , Citosol/metabolismo , Rim/citologia , Análise de Variância , Angiotensina II/metabolismo , Animais , Fator Natriurético Atrial/metabolismo , AMP Cíclico/metabolismo , Cães , Receptores de Angiotensina/metabolismo , Espectrometria de Fluorescência
19.
Artif Organs ; 19(5): 470-4, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7625929

RESUMO

Ten experimental perfusions with autogenous oxygenation were performed in mongrel dogs to evaluate the efficacy of the procedure in maintaining normal hemodynamic the efficacy of the procedure in maintaining normal hemodynamic conditions and adequate blood gases for 1 h. Blood was drained from the right and left atria and pumped to the pulmonary artery and aorta, respectively. Two closed circuits containing compliant chambers and roller pumps were utilized. Artificial ventilation with an FiO2 of 50% were used in 5 animals and with an FiO2 level of 30% in the other 5. EKG, cardiac output, aortic, pulmonary artery, and left atrium pressures were registered. Pulmonary tissue was biopsied after perfusion. The heart was electrically fibrillated after perfusion was established and defibrillated at the end of the bypass. The procedure was able to maintain blood gases and pulmonary, aortic, and left atrial pressures within normal ranges during the perfusion. The mobility of the heart and the access to all coronary arteries was excellent. Clinical central nervous system evaluation, EKG tracings, and pulmonary histological exams showed no adverse effects of perfusion. We conclude that the technique employed may present a suitable proceeding for extracorporeal circulation in closed heart surgeries, and its clinical application should be evaluated as a safe and economical alternative.


Assuntos
Circulação Extracorpórea , Oxigenação por Membrana Extracorpórea , Animais , Aorta/fisiologia , Função do Átrio Esquerdo , Pressão Sanguínea , Dióxido de Carbono/sangue , Débito Cardíaco , Ponte Cardiopulmonar , Cães , Eletrocardiografia , Circulação Extracorpórea/métodos , Derivação Cardíaca Esquerda , Hemodinâmica , Pulmão/patologia , Oxigênio/sangue , Artéria Pulmonar/fisiologia , Respiração Artificial
20.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;28(5): 609-13, May 1995. tab, graf
Artigo em Inglês | LILACS | ID: lil-154884

RESUMO

The effect of angiotensin II (ANG II) and atrial natriuretic peptide (ANP) on intracellular free calcium concentration [ Ca²+]i was investigated in Mandin-Darby canine kidney (MDCK) cells in culture. Changes in [Ca²+]i were monitored fluorometrically with the Ca²+ -sensitive probel fura -2/AM at 37ºC using Perkin-Elmer LS-5 spectrofluorimeter (excitation 340/380 nm,slite 3 nm; emission 520 nm, slit 10 nm). MDCK cells exhibited a mean baseline [Ca²+]i of 98 ñ 10 nM. the addition of increasing concentrations of SNG II (1 pM to 1 µM) to the cell suspension led to a progressive increase in [Ca²+]i to 2-3 times basal levels. In contrast, addition of 1 µM ANP to the cell suspension led to a very rapid 60 percent decrease in [Ca²+]i. The addition of 1 pM to 1 µM ANG II immediately after 1 µM ANP caused an increase in [Ca²+]i which never exceded the basal level in the absence of ANP. The data indicate that ANG II increases cell [Ca²+]i as expected, and provide the new observation that ANP reduces [Ca²+]i in these cells. Further more, ANP reduces the increase in [Ca²+]i elicited by ANG II, thus modulating the effect of ANG II on [Ca²+]i


Assuntos
Animais , Cães , Angiotensina II/farmacologia , Cálcio/sangue , Fator Natriurético Atrial/farmacologia , AMP Cíclico/metabolismo , Análise de Variância , Angiotensina II/metabolismo , Fator Natriurético Atrial/metabolismo , Rim/irrigação sanguínea , Rim/citologia , Receptores de Angiotensina/metabolismo , Espectrometria de Fluorescência
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