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1.
Ultrasound Obstet Gynecol ; 32(1): 5-11, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18512854

RESUMO

OBJECTIVE: Trisomy 21 is associated with a flat face, which can now be quantified by measurement of the frontomaxillary facial (FMF) angle. The aim of this study was to examine whether in trisomy 21 fetuses fetal nuchal translucency (NT) thickness and maternal serum free ss-human chorionic gonadotropin (ss-hCG) and pregnancy-associated plasma protein-A (PAPP-A) are independent of the FMF angle, and to estimate the performance of a first-trimester screening test for trisomy 21 that includes measurement of the FMF angle. METHODS: This was a prospective study in singleton pregnancies at 11 + 0 to 13 + 6 weeks of gestation in which three-dimensional volumes of the fetal head were obtained and measurement of the FMF angle performed immediately before fetal karyotyping by chorionic villus sampling (CVS). The women chose to have CVS after risk assessment by a combination of maternal age, fetal NT thickness and maternal serum free ss-hCG and PAPP-A. Regression analysis was used to examine the significance of the association within the euploid and within the trisomy 21 fetuses between the deviation from the normal median in FMF angle and the deviation in NT, free ss-hCG and PAPP-A. We estimated the detection rate (DR) and false positive rate (FPR) of first-trimester screening for trisomy 21 by measuring the FMF angle in all cases and of an alternative policy in which first-stage screening is by fetal NT and maternal serum biochemistry in all patients, followed by second-stage assessment of FMF angle only in those with an intermediate risk (1 in 51 to 1 in 1000) after the first stage. RESULTS: The FMF angle was measured in 782 euploid and 108 trisomy 21 fetuses. In the euploid fetuses the mean FMF angle decreased linearly with CRL from 83.5 degrees at a crown-rump length (CRL) of 45 mm to 76.4 degrees at a CRL of 84 mm. In the euploid fetuses the mean delta FMF angle was 0.0 (SD, 4.264) degrees and the respective values in the trisomy 21 fetuses were 7.172 (SD, 4.092) degrees . Incorporating the FMF angle in first-trimester combined screening increased the estimated DR from 90 to 94% at an FPR of 5% and from 85 to 92% at an FPR of 3%. In two-stage screening it would be necessary to measure the FMF angle in 12% of cases and the DRs would be 93 and 91% at FPRs of 5 and 3%, respectively. CONCLUSIONS: Measurement of the FMF angle improves the performance of first-trimester screening for trisomy 21.


Assuntos
Síndrome de Down/diagnóstico por imagem , Face/diagnóstico por imagem , Ossos Faciais/diagnóstico por imagem , Pescoço/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adolescente , Adulto , Gonadotropina Coriônica Humana Subunidade beta/sangue , Estatura Cabeça-Cóccix , Síndrome de Down/sangue , Síndrome de Down/diagnóstico , Face/embriologia , Feminino , Humanos , Imageamento Tridimensional , Idade Materna , Pessoa de Meia-Idade , Pescoço/embriologia , Medição da Translucência Nucal , Gravidez/sangue , Primeiro Trimestre da Gravidez/sangue , Segundo Trimestre da Gravidez , Gravidez de Alto Risco , Proteína Plasmática A Associada à Gravidez/análise , Diagnóstico Pré-Natal/métodos , Estudos Prospectivos , Adulto Jovem
2.
J Pharm Biomed Anal ; 43(3): 1078-85, 2007 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-17045772

RESUMO

The in vitro metabolic kinetics of letrozole were investigated by incubating letrozole (10-500 microM) in female or male rat liver microsomes to assess the effect of gender and to predict the in vivo biotransformation characteristics of letrozole in rats. The effects of tamoxifen (TAM) on the metabolic kinetics of letrozole were also examined by incubating letrozole in female rat liver microsomes in the presence or absence of TAM. The effects of chronic pretreatment of female rats with TAM (0.5, 1.0, 5.0 mg/kg/day, i.p. for 7 consecutive days) on liver microsomal protein content and metabolic activity were also examined. The formation rate of the carbinol metabolite of letrozole, CGP44 645, was significantly higher (p<0.05) in male rat liver microsomes in comparison to female. The V(max)/K(m) ratio for letrozole metabolism in female rat liver microsomes did not change significantly (p>0.05) in the presence of TAM. After chronic pretreatment of female rats with TAM (up to a dose of 1.0mg/kg/day), the hepatic microsomal protein content was significantly increased but the formation rate of CGP44 645, when normalized for protein content, did not change significantly. These results suggest that there is a marked gender difference in letrozole metabolism in rats. It also appears that acute treatment of female rat liver microsomes with TAM produces negligible inhibitory effect on the CYP mediated metabolic clearance of letrozole. However, chronic pretreatment of female rats with TAM appear to induce CYPs, but does not significantly impact the metabolic activities of the enzymes associated with the formation of the carbinol metabolite of letrozole.


Assuntos
Antineoplásicos Hormonais/farmacologia , Antineoplásicos/farmacocinética , Microssomos Hepáticos/metabolismo , Nitrilas/farmacocinética , Tamoxifeno/farmacologia , Triazóis/farmacocinética , Animais , Biotransformação , Calibragem , Cromatografia Líquida de Alta Pressão , Interações Medicamentosas , Feminino , Técnicas In Vitro , Letrozol , Masculino , Espectrometria de Massas , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Caracteres Sexuais , Espectrofotometria Ultravioleta
3.
Ultrasound Obstet Gynecol ; 28(3): 261-5, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16865677

RESUMO

OBJECTIVE: To investigate the mid-facial hypoplasia of fetuses with trisomy 21 at 11 + 0 to 13 + 6 weeks of gestation, by three-dimensional (3D) evaluation of the maxilla and the nasal bones. METHODS: A 3D volume of the fetal head was obtained before fetal karyotyping at 11 + 0 to 13 + 6 (median 12) weeks of gestation in 80 fetuses that were subsequently found to have trisomy 21 and in 862 fetuses subsequently found to be chromosomally normal. The multiplanar mode was used to obtain a sequence of transverse views of the fetal face and to demonstrate the maxilla, the adjacent rami of the mandible and the nasal bones. The maxillary depth, defined as the distance between the alveolus of the maxilla in the midline anteriorly and the midpoint of the line joining the rami posteriorly, was measured. Ossification of the nasal bones was considered to be normal if both bones were more echogenic than the overlying skin. RESULTS: In the chromosomally normal group the maxillary depth increased linearly with crown-rump length (CRL) from 3.1 mm at a CRL of 45 mm to 4.8 mm at a CRL of 84 mm, and in the trisomy 21 fetuses the depth was significantly smaller than normal (mean difference = - 0.3 mm, P < 0.001). There was no significant association between the delta maxillary depth and delta nuchal translucency thickness in either the trisomy 21 or the chromosomally normal fetuses. Impaired ossification of the nasal bones was observed in 3.1% of the chromosomally normal fetuses and in 60.0% of those with trisomy 21. The mean maxillary depth was significantly smaller in fetuses demonstrating impaired ossification than in those with normal ossification of the nasal bones (mean difference = -0.2 mm; 95% CI, -0.3 to -0.1, P = 0.001). CONCLUSIONS: In a high proportion of fetuses with trisomy 21 there is sonographic evidence of mid-facial hypoplasia at 11 + 0 to 13 + 6 weeks of gestation.


Assuntos
Síndrome de Down/diagnóstico por imagem , Ossos Faciais/anormalidades , Medição da Translucência Nucal/métodos , Ultrassonografia Pré-Natal/métodos , Adolescente , Adulto , Estudos de Casos e Controles , Amostra da Vilosidade Coriônica , Ossos Faciais/diagnóstico por imagem , Feminino , Idade Gestacional , Humanos , Imageamento Tridimensional/métodos , Cariotipagem , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Gravidez , Segundo Trimestre da Gravidez
4.
J Chromatogr B Biomed Sci Appl ; 763(1-2): 165-71, 2001 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-11710575

RESUMO

A method that allows the measurement of plasma and brain levels of the centrally-acting analgesic tramadol and its major metabolite (O-desmethyl tramadol) in mice and rats was developed using gas chromatography equipped with nitrogen-phosphorus detection (GC-NPD). Plasma samples were extracted with methyl tert.-butyl ether (MTBE) and were injected directly into the GC system. Brain tissue homogenates were precipitated with methanol, the resulting supernatant was dried then acidified with hydrochloric acid. The aqueous solution was washed with MTBE twice, alkalinized, and extracted with MTBE. The MTBE layer was dried, reconstituted and injected into the GC system. The GC assay used a DB-1 capillary column with an oven temperature ramp (135 to 179 degrees C at 4 degrees C/min). Dextromethorphan was used as the internal standard. The calibration curves for tramadol and O-desmethyl tramadol in plasma and brain tissue were linear in the range of 10 to 10000 ng/ml (plasma) and ng/g (brain). Assay accuracy and precision of back calculated standards were within +/- 15%.


Assuntos
Analgésicos Opioides/metabolismo , Cromatografia Gasosa/métodos , Tramadol/metabolismo , Analgésicos Opioides/sangue , Animais , Calibragem , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nitrogênio , Fósforo , Ratos , Padrões de Referência , Tramadol/sangue
5.
J Allergy Clin Immunol ; 103(6): 1081-91, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10359890

RESUMO

BACKGROUND: Airway epithelial cells are among the first cells to come in contact with aerosolized corticosteroids. However, the relative potencies and time course of action of the several commonly used aerosolized corticosteroids on eicosanoid production by airway epithelial cells are unknown. OBJECTIVES: This study compared the effects of fluticasone, budesonide, and triamcinolone on eicosanoid output by human airway epithelial cells in vitro. We also determined the spectrum of eicosanoids affected and the mechanism for corticosteroid action. METHODS: Cultured BEAS-2B airway epithelial cells (a transformed cell line) were exposed to corticosteroids (1 nmol/L to 1 micromol/L) for 2 to 48 hours and then assayed for basal- and bradykinin (BK)-stimulated eicosanoid output. The eicosanoid profile was identified by HPLC in tritiated arachidonic acid prelabelled cells, and PGE2, the major eicosanoid product, was quantitated by RIA. The effect of corticosteroids on the immunoreactivity of key proteins involved in eicosanoid metabolism (ie, cyclooxygenase [COX], phospholipase A2 [PLA2], and Clara cell protein, a PLA2 inhibitor) was determined by Western blotting. RESULTS: Eicosanoid output was largely confined to prostaglandins with values of 5 +/- 2 and 82 +/- 35 ng PGE2/10(6) cells for basal- and BK stimulation, respectively (n = 8). All 3 corticosteroids inhibited basal- and BK-induced PGE2 output in a dose- and time-dependent manner. Fluticasone and budesonide completely eliminated PGE2 output in nanomolar concentrations in contrast to triamcinolone, which required micromolar concentration. The rank order of potency was: fluticasone = budesonide > triamcinolone. The time course of action for PGE2 inhibition also differed, with budesonide acting more slowly than the other 2 corticosteroids (P = .04). All 3 corticosteroids markedly reduced COX2 with little effect on COX1, cPLA2 (Type IV), or iPLA2 (Type VI) immunoreactivity or their relative distribution in cytosol versus membrane fractions. Clara cell protein immunoreactivity was undetectable in control and corticosteroid-treated cell lysates. CONCLUSION: These results show that in a human airway epithelial cell line, the 3 inhaled corticosteroids commonly used to treat asthma differ in onsets of action as inhibitors of prostaglandin synthesis and vary considerably in potency. All 3 corticosteroids act mechanistically in similar fashion by inhibiting COX2 synthesis.


Assuntos
Corticosteroides/administração & dosagem , Eicosanoides/metabolismo , Células Epiteliais/metabolismo , Mediadores da Inflamação/farmacologia , Uteroglobina , Administração Tópica , Androstadienos/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Bradicinina/farmacologia , Brônquios/citologia , Budesonida/administração & dosagem , Células Cultivadas , Dinoprostona/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/metabolismo , Células Epiteliais/efeitos dos fármacos , Fluticasona , Glucocorticoides , Humanos , Fosfolipases A/antagonistas & inibidores , Fosfolipases A/biossíntese , Fosfolipases A2 , Prostaglandina-Endoperóxido Sintases/biossíntese , Biossíntese de Proteínas , Fatores de Tempo , Triancinolona/administração & dosagem
6.
Teratology ; 57(2): 79-84, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9562680

RESUMO

Dysmorphogenesis in diabetic mothers occurs more frequently than in the general population. This phenomenon is believed to be caused by the teratogenic effects of metabolic fuel mixtures with associated membrane injury and aberrations in the biochemical constituents. The present experiment was designed to determine: 1) if hyperglycemia-induced membrane injury is associated with intracellular and/or extracellular lipid disturbances; 2) if supplemental myo-inositol therapy prevents hyperglycemia-induced embryopathy; 3) if a correlation exists between dietary myo-inositol, serum and tissue levels of myo-inositol, and conceptus development; and 4) the cellular content of arachidonic acid following myo-inositol supplementation. Sixty-five female Sprague-Dawley rats were mated, and divided into three groups. One group was nondiabetic normal controls, and two groups had diabetes experimentally induced with streptozotocin. Of the diabetic groups, one received a normal diet, while the other received a myo-inositol-supplemented diet during the period of organogenesis. Blood samples were collected on days 0 and 12 of pregnancy. Embryos and yolk sacs were analyzed for myo-inositol and arachidonic acid levels, using mass spectrochromatography. Dietary myo-inositol supplementation of diabetic mothers resulted in a significant decrease in the incidence of neural tube defects when compared with diabetics not receiving supplements (9.5 vs. 20.4%; P < 0.05). This protective effect was incomplete, based on the incidence observed in the nondiabetic controls (9.5 vs. 3.8%; P < 0.05). The myo-inositol embryonic tissue levels in the diabetic group which had been fed a regular diet without supplementation were significantly lower than in the nondiabetic group. Dietary therapy successfully restored myo-inositol levels in the yolk sacs, as suggested by similar tissue levels in diabetics receiving myo-inositol supplementation and normal controls (18.7 +/- 1.3 vs. 19.1 +/- 2.0 ng/mg; P = ns). Dietary therapy, however, failed to restore myo-inositol levels in the embryos, suggesting hyperglycemia-induced faulty transport of nutrients from the yolk sac to the embryo. No correlation was noted between maternal blood levels of myo-inositol, with or without supplementation, and the clinical outcome. Tissue arachidonic acid levels were markedly reduced in the conceptuses of diabetic mothers with (0.4 +/- 0.1 micrograms/mg) or without (0.25 +/- 0.08 micrograms/mg) myo-inositol supplementation when compared to the nondiabetic controls (3.33 +/- 0.24 micrograms/mg). These data demonstrate that diabetes-induced embryopathy is associated with a deficiency state in both myo-inositol and arachidonic acid. The myo-inositol deficiency is not demonstrated at the serum level, but rather at the tissue level, suggesting a paracrine action. Dietary supplementation of myo-inositol is associated with an increase in tissue myo-inositol levels and a decrease in malformations. This therapy holds promise for use as a dietary prophylaxis against diabetic embryopathy.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Embrião de Mamíferos/anormalidades , Hiperglicemia/metabolismo , Inositol/uso terapêutico , Defeitos do Tubo Neural/prevenção & controle , Gravidez em Diabéticas/metabolismo , Animais , Ácido Araquidônico/metabolismo , Glicemia/metabolismo , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário e Fetal , Feminino , Inositol/administração & dosagem , Inositol/sangue , Inositol/metabolismo , Organização e Administração , Gravidez , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Saco Vitelino/metabolismo
7.
Am J Obstet Gynecol ; 176(3): 536-9, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9077602

RESUMO

OBJECTIVE: Embryopathy in diabetic mothers occurs at a rate four to five times higher than that observed in the general population. The current investigation was undertaken to assess the use of dietary myo-inositol supplementation as a pharmacologic prophylaxis to obviate the teratogenic effects of hyperglycemia in an in vivo study. STUDY DESIGN: Seventy Sprague-Dawley rats were mated and after conception were randomly divided into five groups: one group was nondiabetic normal controls and four groups had diabetes experimentally induced with streptozotocin. Of the diabetic groups, one received the usual diet, whereas the others received, respectively, 0.08, 0.16, and 0.5 mg/day supplemental myo-inositol orally. RESULTS: With the myo-inositol supplementation (0.08 mg/day), the incidence of neural tube defects was significantly reduced from 20.4% to 9.5% (p < 0.01). The most effective dosage of myo-inositol was 0.08 mg/day. Increasing the dose of myo-inositol beyond that level did not significantly reduce the rate of neural tube defects. However, the resorption rate was increased to 29.8%. CONCLUSION: These data demonstrate that myo-inositol supplementation reduces the incidence of diabetic embryopathy and may serve as a pharmacologic prophylaxis against diabetes-induced congenital malformations.


Assuntos
Diabetes Mellitus Experimental , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Inositol/uso terapêutico , Defeitos do Tubo Neural/prevenção & controle , Gravidez em Diabéticas/tratamento farmacológico , Animais , Feminino , Hiperglicemia/complicações , Defeitos do Tubo Neural/etiologia , Gravidez , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
8.
Eur J Clin Pharmacol ; 51(5): 359-66, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9049575

RESUMO

OBJECTIVE: Pharmacokinetics and haemodynamic effects of a total dose of 15 micrograms.kg-1 sufentanil, an opioid anaesthetic agent, were studied in patients undergoing aortocoronary bypass surgery at three infusion rates of 30 (group I), 5 (group II), and 2 (group III) micrograms.kg-1.min-1, respectively. RESULTS: Plasma concentrations of sufentanil could be optimally characterized by a linear biexponential pharmacokinetic model. Non-compartmental analyses indicated that there was no significant difference in the values of clearance (11.6, 13.3, 14.3 ml.min-1.kg-1), steady-state volume of distribution (0.220, 0.255 and 0.331 l.kg-1) and mean residence time (18.8, 13.3 and 14.3 min) among the groups. The observed mean Cmax values of 421 (group I), 125 (group II), and 53 (group III) ng.ml-1 and observed mean AUC values from 0 to 3 min were all consistent with the dosing regimens. There were large inter-individual variations in haemo-dynamic response. Compared to plasma data, a delay in haemodynamic effects was found. Times to reach peak haemodynamic effect ranged from 4.3 to 4.9 min for group I, from 4.6 to 6.1 min for group II, and from 9.9 to 11.3 for group III. Except heart rate, peak haemodynamic effects in these study patients generally ranged from 20.9% to 35.2%. Significant reductions in the area under the effect-time profiles of mean arterial blood pressure and systemic vascular resistance were observed in group II and group III, but not in group I. Significant reductions in the area under the effect-time profiles of left ventricular stroke work index were observed in group III only. No effect on heart rate was found in any group. CONCLUSION: Our findings suggested that a slower infusion rate of sufentanil at a dose of 15 micrograms.kg-1 tends to give a greater reduction in mean arterial blood pressure, systemic vascular resistance, and left ventricular stroke work index than does a faster infusion rate.


Assuntos
Analgésicos Opioides/farmacocinética , Hemodinâmica/efeitos dos fármacos , Sufentanil/farmacocinética , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/sangue , Ponte de Artéria Coronária , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sufentanil/administração & dosagem , Sufentanil/sangue
9.
J Chromatogr B Biomed Appl ; 685(1): 59-66, 1996 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-8930754

RESUMO

We have modified and validated a capillary GC-MS method reported by Kadowaki et al. [J. Chromatogr., 308 (1984) 329] for the determination of diclofenac in human plasma by using heptane rather than benzene as an extraction agent. In addition, acetone was added to the samples as a deproteination agent which increased the recovery of diclofenac. These revised processes allowed clean extraction and near-quantitative recovery of analyte (> 95%). Separation was achieved on an HP-1 column with helium as carrier gas. The parent ion peaks of diclofenac (m/z 277) and the internal standard, 4'-methoxydiclofenac (m/z 307), were monitored by a mass-selective detector using the selected-ion monitoring mode. The linear range for the routine assay was from 5 to 2000 ng/ml. The detection and lower quantifiable limits were 0.2 and 1 ng/ml, respectively, with no interference from plasma. The within-day and between-day coefficients of variation for high and medium concentrations were less than 5% and were less than 13% for low concentrations (10 ng/ml). This GC-MS assay method has been used for pharmacokinetic and drug interaction studies in humans.


Assuntos
Anti-Inflamatórios não Esteroides/sangue , Diclofenaco/sangue , Cromatografia Gasosa-Espectrometria de Massas/métodos , Acetona , Calibragem , Monitoramento de Medicamentos , Heptanos , Humanos , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Am J Obstet Gynecol ; 175(4 Pt 1): 793-9, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8885724

RESUMO

OBJECTIVE: In this study we sought to determine whether dietary supplementation with vitamin E, a known antioxidant, would reduce the incidence of diabetic embryopathy in an in vivo rat model. STUDY DESIGN: Eighty-day-old Sprague-Dawley rats were assigned to one of five groups: two control groups (groups 1 and 2) and three diabetic groups (groups 3, 4, and 5). One group of controls (group 2) and one group of diabetic rats (group 4) received dietary supplements of vitamin E (440 mg/day). The other three groups (groups 1, 3, and 5) received a normal diet only. Group 5 received insulin therapy to control glucose levels. On day 6 of gestation diabetes was induced in groups 3, 4, and 5 with streptozotocin (65 mg/kg). Animals were killed on day 12; embryos were examined for size, protein content, evidence of malformations, and superoxide dismutase activity. RESULTS: In both groups (groups 3 and 4) of diabetic rats the mean blood glucose level than was significantly higher in controls. Insulin-treated animals (group 5) had glucose levels that were comparable to those of controls. The unsupplemented diabetic group had a neural tube defect rate of 21.48% +/- 9.6% (percentage of neural tube defects per rat) and a resorption rate of 21.37% +/- 20.39% (percentage of resorptions per rat) as compared with rates in the supplemented diabetic group of 6.92% +/- 4.08% and 2.17% +/- 3.74%, respectively (p < 0.01). Groups 1, 2, and 5 had similar neural tube defect rates (6.63% +/- 5.0%, 5.01% +/- 4.87%, and 3.55% +/- 5.92%, respectively. Vitamin E levels, measured by high-performance liquid chromatography, were significantly higher in maternal serum and embryos in the supplemented groups (p < 0.001) than in controls. Superoxide dismutase activity was reduced in the diabetes groups and was not affected by vitamin E therapy. CONCLUSIONS: Supplementation with the antioxidant vitamin E confers a significant protective effect against diabetic embryopathy and may potentially serve as a dietary prophylaxis in the future. We postulate that this protective effect is mediated by a reduction in the oxidative load induced by hyperglycemia.


Assuntos
Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Reabsorção do Feto/prevenção & controle , Defeitos do Tubo Neural/prevenção & controle , Gravidez em Diabéticas , Vitamina E/administração & dosagem , Animais , Diabetes Mellitus Experimental/sangue , Dieta , Feminino , Reabsorção do Feto/epidemiologia , Reabsorção do Feto/etiologia , Incidência , Insulina/uso terapêutico , Defeitos do Tubo Neural/epidemiologia , Defeitos do Tubo Neural/etiologia , Gravidez , Ratos/embriologia , Ratos Sprague-Dawley , Superóxido Dismutase/sangue , Vitamina E/sangue , Vitamina E/uso terapêutico
11.
Am J Obstet Gynecol ; 175(4 Pt 1): 818-23, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8885728

RESUMO

OBJECTIVE: The purpose of the current study was to determine whether a dietary source of arachidonic acid could serve as a pharmacologic prophylaxis to obviate the teratogenic effects of hyperglycemia. STUDY DESIGN: Eighty-day-old Sprague-Dawley rats were mated, and after conception were randomly allocated to five groups: two groups were nondiabetic normal controls and three groups had diabetes experimentally induced with streptozocin. Of the two control groups, one was fed a normal diet (group 1) and the other group (group 2) received a normal diet and 1.0 ml of safflower oil, a polyunsaturated fatty acid known to increase serum arachidonic acid levels. In the three diabetic groups (groups 3, 4, and 5) glucose levels were allowed to remain > 350 mg/dl by withholding daily insulin therapy. Group 3 received a normal diet without supplementation; group 4 received a normal diet plus normal saline solution sham feedings, whereas group 5 received a normal diet supplemented with 1.0 ml of safflower oil. The oral agents (normal saline solution and polyunsaturated fatty acid) were administered with a tuberculin syringe. RESULTS: Diabetic rats not receiving insulin therapy and receiving normal diets produced offspring with malformation rates of 20% compared with control rates of 4.8%. Supplemental normal saline solution or safflower oil given orally to controls did not alter the growth or malformation rates. These rates were similarly unaffected in the diabetic rats receiving oral supplementation of normal saline solution. However, with safflower oil supplementation to diabetic rats the incidence of neural tube defects was decreased from 20.0% to 7.6% (p < 0.0001). An inverse relationship was observed between the malformation rate and the serum arachidonic acid level: 17.83 (SD 5.84 micrograms/ml) in the nondiabetic controls, with a malformation rate of 4.8%, versus 14.18 (SD 2.58 micrograms/ml) in the diabetic rats, with a malformation rate of 20.0% (p < 0.05). With safflower oil supplementation serum levels of arachidonic increased from 14.18 +/- 2.58 micrograms/ml to 19.99 +/- 7.99 micrograms/ml (p < 0.05); this was associated with a concomitant decline in the malformation rate. CONCLUSION: These data demonstrate that diabetic embryopathy is associated with a deficiency state in essential fatty acid, corroborating our previous in vitro findings. Furthermore, the use of a dietary polyunsaturated fatty acid that specifically increases arachidonic levels significantly reduced the incidence of diabetic embryopathy. These findings may serve as a basis for developing strategies of pharmacologic prophylaxis against diabetes-induced congenital malformations.


Assuntos
Ácido Araquidônico/farmacologia , Diabetes Mellitus Experimental/complicações , Gorduras na Dieta/farmacologia , Reabsorção do Feto/prevenção & controle , Defeitos do Tubo Neural/prevenção & controle , Gravidez em Diabéticas , Animais , Ácido Araquidônico/sangue , Feminino , Reabsorção do Feto/etiologia , Defeitos do Tubo Neural/etiologia , Projetos Piloto , Gravidez , Resultado da Gravidez , Ratos , Ratos Sprague-Dawley , Óleo de Cártamo/farmacologia
12.
Am J Respir Cell Mol Biol ; 13(4): 410-7, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7546770

RESUMO

Adenosine triphosphate (ATP) acting through epithelial nucleotide receptors exerts multiple physiologic actions on airway mucociliary clearance and caliber. However, the effect of ATP on arachidonate metabolism in the airway remains unknown. In this study, the ability of ATP to regulate eicosanoid production was studied in vitro in full-thickness rabbit tracheal strips and separately in rabbit epithelial explant cultures. In the freshly isolated strips, ATP increased prostaglandin E2 (PGE2) release in a dose-dependent fashion, with an activation threshold at 10 microM ATP and a 3.5-fold increase in PGE2 output at 1 mM ATP. Epithelium removal decreased 1 mM ATP-evoked PGE2 release by 68%. Reverse-phase, high-pressure liquid chromatography (HPLC) of media from 3H-arachidonic acid-incubated epithelial explants exposed to 1 mM ATP demonstrated increased output of the cyclooxygenase products PGE2 and prostaglandin F2a (PGF2a). Other identifiable eicosanoids did not increase. The concentration-response for ATP-induced PGE2 release by explants was similar to that of tracheal strips. PGE2 release by 1 mM ATP was 27% of that elicited by ionomycin (10 microM) and was markedly inhibited by indomethacin (10 microM). Purinoceptor agonist-stimulated PGE2 release by the epithelium yielded a rank order of potency of uridine triphosphate (UTP) > or = ATP > 2-methylthio-ATP (2MeSATP) >> alpha,beta-methyleneadenosine-5'-triphosphate (AMP-CPP) > or = adenosine. These results indicate that ATP, acting primarily through an epithelial P2-purinoceptor similar to the P2a subtype, stimulates eicosanoid metabolism in rabbit airway epithelium via the cyclooxygenase pathway, producing PGE2 as the predominant species.


Assuntos
Trifosfato de Adenosina/farmacologia , Dinoprostona/biossíntese , Receptores Purinérgicos P2/fisiologia , Traqueia/metabolismo , Animais , Técnicas de Cultura , Dinoprosta/biossíntese , Epitélio/metabolismo , Ionomicina/farmacologia , Masculino , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Agonistas do Receptor Purinérgico P2 , Coelhos , Organismos Livres de Patógenos Específicos , Traqueia/efeitos dos fármacos , Uridina Trifosfato/farmacologia
13.
Control Clin Trials ; 15(5): 411-28, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8001360

RESUMO

A statistical wit once remarked that researchers often pose the wrong question and then proceed to answer that question incorrectly. The question that researchers intend to ask is whether or not a treatment effect is clinically significant. The question that is typically asked, however, is whether or not the treatment effect is statistically significant--a question that may be only marginally related to the issue of clinical impact. Similarly, the response, in the form of a p value, is typically assumed to reflect clinical significance but in fact reflects statistical significance. In an attempt to address this problem the medical literature over the past decade has been moving away from tests of significance and toward the use of confidence intervals. Concretely, study reports are moving away from "the difference was significant with a p value under 0.01" and toward "the one-year survival rate was increased by 20 percentage points with a 95% confidence interval of 15 to 24 percentage points." By focusing on what the effect is rather than on what the effect is not confidence intervals offer an appropriate framework for reporting the results of clinical trials. This paper offers a non-technical introduction to confidence intervals, shows how the confidence intervals framework offers advantages over hypothesis testing, and highlights some of the controversy that has developed around the application of this method. Additionally, we make the argument that studies which will be reported in terms of confidence intervals should similarly be planned with reference to confidence intervals. The sample size should be set to ensure that the estimates of effect size will be reported not only with adequate power but also with appropriate precision.


Assuntos
Intervalos de Confiança , Ensaios Clínicos Controlados como Assunto/métodos , Ensaios Clínicos Controlados como Assunto/estatística & dados numéricos , Interpretação Estatística de Dados , Humanos , Incidência , Recidiva Local de Neoplasia/epidemiologia , Neoplasias/tratamento farmacológico , Resultado do Tratamento
14.
Radiology ; 179(1): 66-8, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2006306

RESUMO

Inflammatory pseudosarcoma of the bladder is a rare benign entity that cannot be differentiated from malignant tumor at radiologic examination alone. Only pathologic examination can enable a definitive diagnosis. The authors report two cases of these benign tumors in patients with no history of bladder disease or trauma; the tumors were large, demonstrated invasion into local tissues, and recurred in one case after incomplete transurethral resection.


Assuntos
Fibroma/diagnóstico por imagem , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Adulto , Feminino , Fibroma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Neoplasias da Bexiga Urinária/patologia
16.
J Clin Psychiatry ; 44(5 Pt 2): 134-6, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6406442

RESUMO

The efficacy and safety of bupropion, an atypical antidepressant, were assessed in depressed patients aged 55 and above. Data were analyzed for 38 patients who completed 4 weeks of double-blind treatment with bupropion in maximum doses of 150 or 450 mg/day; imipramine, up to 200 mg/day; or placebo. Preliminary results suggest that bupropion does have antidepressant activity and is well tolerated in this population. A particular advantage is suggested in terms of cardiovascular side effects.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo/tratamento farmacológico , Propiofenonas/uso terapêutico , Fatores Etários , Idoso , Bupropiona , Ensaios Clínicos como Assunto , Transtorno Depressivo/psicologia , Método Duplo-Cego , Feminino , Humanos , Imipramina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Distribuição Aleatória
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