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1.
Ann Pharm Fr ; 77(3): 212-221, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30803767

RESUMEN

OBJECTIVES: Norepinephrine is usually used in emergency situations such as in intensive care units (ICUs) for the restoration of blood pressure. The objective was to study the stability of highly-concentrated solutions of norepinephrine at 0.50mg/mL and 1.16mg/mL, diluted in glucose 5% (G5%) in polypropylene syringes, protected or not from light, up to 48h. MATERIALS AND METHODS: Chemical stability was analysed by high-performance liquid chromatography coupled to photodiode array detection at each time of the analysis. The method was validated according to the International Conference on Harmonisation Q2(R1). Physical stability was evaluated by visual and subvisual inspection. Three syringes for each condition were prepared. At each time of the analysis, three samples were analysed for each syringe. pH values were evaluated at each moment of the analysis. RESULTS: Solutions of norepinephrine at 0.50 and 1.16mg/mL, diluted in G5%, with or without protection from light, retained more than 95.0% of the initial concentration after a 48-hour storage at 20-25°C. No visual and subvisual modification occured during the stability study. No degradation product appearing during the stressed degradation was observed during the study but an additional peak with a relative retention at 0.66 was observed and constant. This peak was identified as 5-hydroxymethylfurfural, a degradation product of glucose. CONCLUSION: Norepinephrine diluted in G5% at 0.50mg/mL and 1.16mg/mL was physically and chemically stable over a period of 48hours at room temperature. These stability data of highly concentrated solutions provide additional knowledge to assist intensive care services in daily practice.


Asunto(s)
Unidades de Cuidados Intensivos/estadística & datos numéricos , Norepinefrina/análisis , Vasoconstrictores/análisis , Cromatografía Líquida de Alta Presión , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Furaldehído/análogos & derivados , Furaldehído/análisis , Concentración de Iones de Hidrógeno , Luz , Norepinefrina/administración & dosificación , Polipropilenos , Reproducibilidad de los Resultados , Jeringas , Temperatura , Vasoconstrictores/administración & dosificación
2.
J Forensic Sci ; 64(3): 950-955, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30380149

RESUMEN

The present study involved segmental testing of hair in two clinical cases with known dosage histories. Hair analysis confirmed the first patient's exposure to the prescribed sertraline and citalopram for several months. Citalopram was generally distributed along the hair shaft in accordance with the drug ingestion period. By contrast, "false" positive results were observed for sertraline in distal hair segments, corresponding to a period of no sertraline exposure, which may indicate incorporation from sweat or sebum, which transport the drugs along the hair surface. The second patient received various drugs during her treatment for brain cancer. Metoclopramide, morphine, oxazepam, paracetamol, sumatriptan, tramadol, and zopiclone, which had been part of the therapy, were all detected in the proximal hair segment. The results of these two cases indicated that results-especially concerning the time of drug intake-must be interpreted with caution and allow for the possibility of incorporation from sweat or sebum.


Asunto(s)
Analgésicos/análisis , Cabello/química , Hipnóticos y Sedantes/análisis , Inhibidores Selectivos de la Recaptación de Serotonina/análisis , Vasoconstrictores/análisis , Acetaminofén/análisis , Adulto , Antieméticos/análisis , Compuestos de Azabiciclo/análisis , Citalopram/análisis , Femenino , Toxicología Forense , Cabello/crecimiento & desarrollo , Humanos , Metoclopramida/análisis , Morfina/análisis , Oxazepam/análisis , Piperazinas/análisis , Sertralina/análisis , Sumatriptán/análisis , Tramadol/análisis
3.
J Pharm Biomed Anal ; 41(4): 1468-72, 2006 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-16698212

RESUMEN

A simple and rapid procedure based on gas chromatography-mass spectrometry (GC-MS) is described for determination of synephrine, active principle of Citrus aurantium plant, in solid and liquid dietary supplements. After the addition of 3,4-methylenedioxypropylamphetamine as internal standard (I.S.), a liquid-liquid extraction procedure in alkaline conditions with chloroform/isopropanol (9:1, v/v) was applied to the samples prior to analysis. Chromatography was performed on a fused capillary column and synephrine and I.S., derivatized with pentafluoropropionic anhydride, were determined in the selected-ion-monitoring (SIM) mode. The method was validated in the range 0.1-50 microg/mg or microg/mL synephrine. Mean recovery ranged between 89.3% and 90.5% in both solid and liquid dietary supplements. The quantification limit was 0.1 microg/mg or microg/ml. The method was applied to analysis of various dietary supplements promoted for aiding weight control containing, among other constituents such as ephedrine alkaloids and methylxanthines, Citrus aurantium. Amount of synephrine present in such products ranged from 3.1 microg/mg solid product to 480.2 microg/mL liquid product.


Asunto(s)
Citrus , Alimentos Formulados/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Sinefrina/análisis , Vasoconstrictores/análisis , Reproducibilidad de los Resultados
4.
Knee Surg Sports Traumatol Arthrosc ; 14(2): 133-40, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16133445

RESUMEN

Adrenergic reactions could mediate metabolic and circulatory changes in the synovial membrane following knee surgery. The interstitial fluid of the synovial membrane and subcutaneous adipose tissue (reference) was monitored in vivo with microdialysis following knee arthroscopy with adrenaline added to the dialysis solvent, adrenaline together with a local anestetic added intra-articularly and without. Local metabolism and blood flow were measured. There was a similar increase, about two fold, in dialysate lactate in all three experimental conditions in the synovial membrane but no change in adipose tissue. Glucose and blood flow decreased by approximately 50% and 10% in both tissues following addition of adrenaline to the dialysate but no changes in the glucose concentrations or blood flow were observed in the other two experimental situations. As regards glycerol the addition of adrenaline caused an approximate 20% increase of the concentration in adipose tissue but an approximate 20% decrease in the synovial membrane. The intra-articular injection caused an approximate 50% increase of the glycerol level in the synovial membrane but no change in adipose glycerol. Thus, the hypermetabolic state in the synovial membrane following standard arthroscopy and the tissue damage (increased glycerol level) in the synovial membrane following postoperative pain relief by intra-articularly injected local anesthetics together with adrenaline doesn't enhance the hypermetabolic state seen postoperatively without adrenaline. However, catecholamines have pronounced in vivo effects on metabolism and blood flow in the synovial membrane.


Asunto(s)
Epinefrina/farmacología , Microdiálisis , Membrana Sinovial/irrigación sanguínea , Membrana Sinovial/metabolismo , Vasoconstrictores/farmacología , Tejido Adiposo/metabolismo , Adolescente , Adulto , Anestésicos Locales/farmacología , Artroscopía , Bupivacaína/farmacología , Soluciones para Diálisis/química , Soluciones para Diálisis/farmacología , Dihidralazina/química , Dihidralazina/farmacología , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Epinefrina/análisis , Etanol/metabolismo , Femenino , Glucosa/metabolismo , Glicerol/metabolismo , Humanos , Inyecciones Intraarticulares , Articulación de la Rodilla/irrigación sanguínea , Articulación de la Rodilla/cirugía , Ácido Láctico/metabolismo , Masculino , Persona de Mediana Edad , Flujo Sanguíneo Regional/efectos de los fármacos , Vasoconstrictores/análisis
5.
Am J Respir Crit Care Med ; 166(3): 301-6, 2002 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-12153961

RESUMEN

The pathogenesis of aspirin-induced asthma (AIA) has not yet been clearly elucidated, although eicosanoid metabolites appear to play an important role. We hypothesized that levels of eicosanoids in exhaled air condensate are abnormal in patients with AIA and that they change in patients receiving steroid therapy. We measured cysteinyl-leukotrienes (cys-LTs), prostaglandin E(2) (PGE(2)), and leukotriene B(4) (LTB(4)), and also 8-isoprostane as a marker of oxidative stress, by enzyme immunoassay in exhaled breath condensate from patients with AIA (17 steroid naive; mean age, 41 +/- 23 years; FEV(1), 63%pred), 26 patients with aspirin-tolerant asthma (ATA) (11 steroid naive; mean age, 47 +/- 18 years; FEV(1), 69%pred), and 16 healthy subjects (mean age, 45 +/- 17 years; FEV(1), 93%pred). Cys-LTs were significantly higher in steroid-naive patients with AIA compared with steroid-naive patients with ATA and healthy subjects (152.3 +/- 30.4 and 36.6 +/- 7.1 versus 19.4 +/- 2.8 pg/ml; p < 0.05 and p < 0.05, respectively). Steroid-naive patients with AIA also had higher levels of 8-isoprostane than normal subjects (131.8 +/- 31.0 versus 21.9 +/- 4.5 pg/ml; p < 0.05). There were significantly lower levels of both cys-LTs and 8-isoprostanes in steroid-treated patients with AIA. There was no difference in either the PGE(2) or LTB(4) level between the patient groups. This is the first study to show that cys-LTs and 8-isoprostanes are elevated in expired breath condensate of steroid-naive patients with AIA, and that cys-LTs are decreased in steroid-treated patients. Exhaled PGE(2) levels are not reduced, so that it is unlikely that a deficiency of PGE(2) is an important mechanism, whereas exhaled LTB(4) levels are unchanged, indicating an abnormality beyond 5-lipoxygenase.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Aspirina/efectos adversos , Asma/inducido químicamente , Asma/metabolismo , Pruebas Respiratorias , Cisteína/análisis , Dinoprost/análogos & derivados , F2-Isoprostanos/análisis , Mediadores de Inflamación/análisis , Leucotrienos/análisis , Sistema Respiratorio/metabolismo , Vasoconstrictores/análisis , Adulto , Dinoprostona/análisis , Femenino , Humanos , Leucotrieno B4/análisis , Masculino , Persona de Mediana Edad , Estrés Oxidativo/fisiología , Oxitócicos/análisis , Sistema Respiratorio/efectos de los fármacos
6.
J Endod ; 27(2): 73-5, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11491641

RESUMEN

Catecholamines may play an important role in the control of intrapulpal pressure as mediators of vasoconstriction. A baseline level of catecholamines (dopamine, epinephrine, and norepinephrine) in the uninflamed human dental pulp was previously reported using high-performance liquid chromatography. The purpose of this study was to compare the level of catecholamines present in the inflamed human dental pulp with the baseline level established in virgin teeth. Twelve uninflamed pulps were analyzed as a control and to validate previous findings. Pulp tissue was obtained from 10 vital and inflamed teeth requiring endodontic treatment. Selective criteria for each patient included: absence of systemic disease, medications, and allergies; a vital response to ice, heat, and electric pulp tests; and periodontal probing < or = 3 mm. A prior history of pain associated with the tooth was an additional criterion for inflamed pulps. To avoid the presence of an exogenous catecholamine, local anesthesia without epinephrine was administered. Dopamine, epinephrine, and norepinephrine were chemically extracted and analyzed by high-performance liquid chromatography with ultraviolet detection. Catecholamine levels found to be present in the pulp during inflammation were greater than the baseline level established in uninflamed pulp tissue.


Asunto(s)
Dopamina/análisis , Epinefrina/análisis , Norepinefrina/análisis , Pulpitis/metabolismo , Cromatografía Líquida de Alta Presión , Frío , Pulpa Dental/química , Pulpa Dental/fisiopatología , Estimulación Eléctrica , Calor , Humanos , Hielo , Presión , Reproducibilidad de los Resultados , Tratamiento del Conducto Radicular , Estadística como Asunto , Rayos Ultravioleta , Vasoconstrictores/análisis
7.
Peptides ; 22(11): 1713-8, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11754956

RESUMEN

Adrenomedullin (AM) is a potent hypotensive peptide originally isolated from pheochromocytoma tissue. Both the ring structure and the C-terminal amide structure of AM are essential for its hypotensive activity. We have developed an RIA which recognizes the ring structure of human AM. Using this RIA, we have characterized the molecular form of AM in bovine adrenal medulla. Gel filtration chromatography revealed that three major peaks of immunoreactive AM existed in the adrenal medulla. The peptide corresponding to Mr 1500 Da was further purified to homogeneity. The peptide was determined to be AM (11-26) which has one intramolecular disulfide bond. Amino acid sequences of bovine AM and its precursor were deduced from the analyses of cDNA encoding bovine AM precursor. The synthetic AM (11-26) produced dose-dependent strong pressor responses in unanesthetized rats in vivo. The hypertensive activity lasted about one minute, and a dose dependent increase in heart rate was also observed. The present data indicate that AM (11-26) is a major component of immunoreactive AM in bovine adrenal medulla and shows pressor activity.


Asunto(s)
Médula Suprarrenal/química , Fragmentos de Péptidos/aislamiento & purificación , Vasoconstrictores/aislamiento & purificación , Adrenomedulina , Secuencia de Aminoácidos , Análisis de Varianza , Animales , Secuencia de Bases , Bovinos , ADN Complementario/análisis , Humanos , Datos de Secuencia Molecular , Fragmentos de Péptidos/análisis , Fragmentos de Péptidos/genética , Radioinmunoensayo , Análisis de Secuencia de Proteína , Porcinos , Vasoconstrictores/análisis
8.
Acta Anaesthesiol Scand ; 44(7): 864-7, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10939700

RESUMEN

BACKGROUND: A low dose solution of adrenaline 2 microg x ml(-1), fentanyl 2 microg x ml(-1) and bupivacaine 1 mg x ml(-1) has been reported to give superior pain control when used for epidural analgesia after major surgery. The present paper describes the compounding and chemical stability of this triple-component solution during storage and use. METHODS: Sterile triple-component concentrates (11X) were diluted by the use of gas isolator technology to give ready-to-use infusion solutions. Eight solutions were analysed by reverse phase high-performance liquid chromatography (HPLC) methods, and assays were performed on 1, 45, 90 and 180 days after storage at 2-8 degrees C. After 180 days the solutions were subsequently stored at 22 degrees C for four days before they were reanalysed. HPLC quantification of adrenaline was also performed on samples from solutions given to 28 different patients. RESULTS: The concentration of adrenaline and fentanyl decreased approximately 3.5% from 1 to 180 days at 4 degrees C and four days at 22 degrees C. The corresponding figure for bupivacaine was an apparent increase by 2.4% in concentration. No absorption to the polypropylene plastic bags of fentanyl and bupivacaine was detected. None of the 28 samples derived from used infusion bags contained less than 95% of the declared content of adrenaline. CONCLUSIONS: The triple-component epidural analgesic solution remained stable during six months of cold storage, followed by four days of storage at room temperature. No significant degradation of adrenaline was observed in infusion solutions returned from the wards.


Asunto(s)
Analgesia Epidural , Analgésicos Opioides/análisis , Anestésicos Locales/análisis , Bupivacaína/análisis , Epinefrina/análisis , Fentanilo/análisis , Vasoconstrictores/análisis , Adsorción , Cromatografía Líquida de Alta Presión , Composición de Medicamentos , Embalaje de Medicamentos , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Luz , Soluciones Farmacéuticas , Temperatura
9.
Cancer Epidemiol Biomarkers Prev ; 9(4): 421-5, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10794487

RESUMEN

Post hoc analysis of data obtained from a study designed to modulate oxidative damage by dietary intervention revealed consistently strong inverse correlations between plasma xanthophyll carotenoids and oxidative damage indices. Thirty-seven women participated in a 14-day dietary intervention that increased mean vegetable and fruit (VF) consumption to approximately 12 servings/day. An additional 10 subjects participated in an intervention that limited VF consumption to less than four servings per day. 8-Hydroxy-2'-deoxyguanosine (8-OHdG) in DNA isolated from peripheral lymphocytes and 8-OHdG excreted in urine were measured as indices of oxidative DNA damage. Lipid peroxidation was assessed by measuring 8-epiprostaglandin F2alpha (8-EPG) in urine. Plasma levels of selected carotenoids were also determined, with the intention of using a-carotene as a biochemical index of VF consumption. Urinary 8-OHdG and 8-EPG were measured by ELISA, and plasma carotenoids were measured by high performance liquid chromatography. Lymphocyte 8-OHdG was measured by reverse phase high performance liquid chromatography with electrochemical detection. We observed that the structurally related xanthophyll carotenoids, lutein and beta-cryptoxanthin, which occur in dissimilar botanical families, were consistently inversely associated with these oxidative indices. Statistically significant inverse correlations were observed between plasma lutein and/or beta-cryptoxanthin levels and lymphocyte 8-OHdG and urinary 8-EPG. Moreover, an inverse correlation was observed between change in plasma xanthophylls and change in lymphocyte 8-OHdG concentration that occurred during the course of the study. These data lead us to hypothesize that lutein and beta-cryptoxanthin serve as markers for the antioxidant milieu provided by plants from which they are derived. Whether these carotenoids are directly responsible for the observed antioxidant phenomena merits further investigation.


Asunto(s)
Daño del ADN , Peroxidación de Lípido , Luteína/sangre , 8-Hidroxi-2'-Desoxicoguanosina , Adulto , Biomarcadores/análisis , Desoxiguanosina/análogos & derivados , Desoxiguanosina/orina , Dieta , Dinoprost/análogos & derivados , Dinoprost/análisis , Femenino , Frutas , Humanos , Linfocitos/química , Vasoconstrictores/análisis , Verduras
10.
Rev Med Brux ; 20(4): A201-5, 1999 Sep.
Artículo en Francés | MEDLINE | ID: mdl-10523893

RESUMEN

This review illustrates the evolution in the clinical use of prostate specific antigen as a prostate cancer tumour marker. Because PSA lacks specificity, several new PSA parameters have been investigated such as the age-referenced PSA and the PSA density of the transition zone. We discuss also the molecular forms of PSA and the complexed PSA and new tumour markers which could be of interest in the future such as the HK2.


Asunto(s)
Biomarcadores de Tumor/análisis , Antígeno Prostático Específico/análisis , Neoplasias de la Próstata/diagnóstico , Adulto , Factores de Edad , Anciano , Humanos , Masculino , Persona de Mediana Edad , Próstata/patología , Neoplasias de la Próstata/patología , Sensibilidad y Especificidad , Calicreínas de Tejido/análisis , Vasoconstrictores/análisis
11.
Hypertension ; 34(4 Pt 2): 872-5, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10523376

RESUMEN

Diadenosine polyphosphates have been identified as important regulators of vascular tone and blood pressure. In reference to the background of the well-known vasoconstriction induced by hemolysate, we questioned whether this action may be due in part to the presence of diadenosine polyphosphates in human erythrocytes. Therefore, erythrocytes were separated from other blood cells and deproteinated. To concentrate and purify nucleotides, the extract was chromatographed by anion exchange, affinity, and reversed-phase columns. In one of the purified fractions, diadenosine hexaphosphate (diadenosine 5', 5'-P(1), P(6) hexaphosphate [AP(6)A]) was identified by matrix-assisted laser desorption/ionization mass spectrometry, ultraviolet spectroscopy, and enzymatic analysis. Hemolysate of erythrocytes injected into the isolated perfused rat kidney induced a dose-dependent vasoconstriction, which was partially inhibited by P(2)-purinoceptor antagonist. The data document the existence of AP(6)A in erythrocytes. AP(6)A may be involved in the pathogenesis of vasospasm induced by free hemoglobin.


Asunto(s)
Fosfatos de Dinucleósidos/análisis , Eritrocitos/metabolismo , Vasoconstrictores/análisis , Animales , Humanos , Ratas
12.
Rheumatology (Oxford) ; 38(6): 529-34, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10402073

RESUMEN

OBJECTIVE: To evaluate the occurrence and clinical significance of lipid peroxidation (oxidative stress) in rheumatic diseases characterized by vascular involvement. PATIENTS AND METHODS: Plasma 8-epi-PGF2alpha (oxidative stress marker) was measured by gas chromatography-mass spectrometry in 36 patients with systemic lupus erythematosus (SLE), 13 with systemic sclerosis (SSc), 13 with systemic vasculitis [Wegener's granulomatosis (WG), n = 4; Churg Strauss syndrome (CSS), n = 3; Behcet syndrome, n = 6], 12 with rheumatoid arthritis (RA) and in 23 healthy controls (n = 23). RESULTS: 8-epi-PGF2alpha levels were higher in patients with SLE (P = 0.007), SSc (P < 0.001) and vasculitis (P = 0.001) than in controls. In SLE, a positive Coombs' test and arterial hypertension independently predicted 8-epi-PGF2alpha concentrations (P = 0.004 and P = 0.001, respectively). SLE patients not taking prednisolone showed higher 8-epi-PGF2alpha concentrations than SLE patients on prednisolone (P = 0.02). In the latter group, a dose response relationship was noted between 8-epi-PGF2alpha and steroid dosage (r = 0.6, P = 0.0003). In WG and CSS, 8-epi-PGF2alpha concentrations correlated with disease activity (r = 0.8, P = 0.01) and were higher than in patients with Behcet disease (P = 0.003). CONCLUSIONS: Oxidative stress may be pathogenetically relevant in some autoimmune rheumatic diseases with vascular involvement. Amelioration of some clinical manifestations of these diseases may be envisaged by targeting lipid peroxidation with dietary or pharmacological antioxidants.


Asunto(s)
Enfermedades Autoinmunes/fisiopatología , Peroxidación de Lípido , Lupus Eritematoso Sistémico/fisiopatología , Estrés Oxidativo , Enfermedades Vasculares/fisiopatología , Adulto , Anciano , Dinoprost/análogos & derivados , Dinoprost/análisis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vasoconstrictores/análisis
13.
J Androl ; 20(3): 348-55, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10386814

RESUMEN

It has been demonstrated that prostate-specific antigen (PSA), in spite of its name, can be detected in body fluids and tumors from a variety of organs. Investigations have shown that human glandular kallikrein 2 (hK2), a related prostate-secreted protease, can activate the zymogen form of PSA, suggesting that the two enzymes might work as a functional unit, with hK2 as the activator molecule and PSA as the effector molecule. If this is true, then hK2 should be found together with PSA in body fluids other than seminal plasma, as well. Recently, a sensitive and specific assay was devised for hK2, enabling its measurement in picogram quantities. With this assay, the concentration of hK2 was determined in samples of seminal plasma, amniotic fluid, breast milk, and saliva. Simultaneously, the samples were assayed for molecular forms of PSA. In seminal plasma, the mean PSA concentration was 0.82 mg/ml, while the hK2 level was around two orders of magnitude lower: mean value, 6.4 microg/ml. Approximately the same ratio of PSA to hK2 as in seminal plasma was found in amniotic fluid and breast milk, but in most samples, the hK2 values were too low for direct measurements and had to be concentrated prior to analysis. Measurable levels of PSA, all in the free form, were detected in amniotic fluid at the thirteenth week of gestation and then gradually increased to levels around and over 1 microg/L from the twentieth week. Significant levels of PSA were detected in amniotic fluid collected at delivery, also. Measurable levels of mammary PSA were primarily detected in colostrum, with a range from less than 0.03 microg/L to 2.1 mg/L. Around half of the molecules were in complex with protease inhibitor. Most surprisingly, determinations on saliva samples showed that none of them had detectable PSA levels but had measurable concentrations of hK2 with a mean value, 0.09 microg/L. The presence in saliva suggests that hK2 can be the human equivalent to one of the mouse salivary kallikreins with important biological function, like the epidermal growth factor-binding protein or the gamma subunit of nerve growth factor. However, this was ruled out, as a phylogenetic analysis showed that the human and mouse glandular kallikreins evolved independently from a common precursor after the separation of the primate and rodent lineages. In conclusion, the measurements show that in addition to the previously known secretion in seminal plasma, hK2 is secreted in amniotic fluid, breast milk, and saliva. Furthermore, the concerted expression of PSA and hK2 in seminal plasma, amniotic fluid, and breast milk suggests that the two proteases might form a functional unit but not always as demonstrated by the sole presence of hK2 in saliva.


Asunto(s)
Líquidos Corporales/química , Calicreínas/análisis , Antígeno Prostático Específico/análisis , Vasoconstrictores/análisis , Líquido Amniótico/química , Animales , Cromatografía en Gel , Calostro/química , Evolución Molecular , Femenino , Humanos , Masculino , Ratones , Leche Humana/química , Filogenia , Saliva/química , Semen/química , Calicreínas de Tejido
14.
Braz J Med Biol Res ; 32(4): 373-81, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10347798

RESUMEN

Estrogen stimulates the renin-angiotensin system by augmenting both tissue and circulating levels of angiotensinogen and renin. We show, however, that angiotensin converting enzyme (ACE) activity in the circulation and in tissues is reduced in two animal models of postmenopausal chronic hormone replacement. We observed a reduction of ACE activity in association with a significant increase in plasma angiotensin I (Ang I) and hyperreninemia in ovariectomized monkeys treated with Premarin (conjugated equine estrogen) replacement for 30 months. Plasma angiotensin II (Ang II) levels were not increased in monkeys treated with estrogen, suggesting that the decrease in ACE curtailed the formation of the peptide. The Ang II/Ang I ratio, an in vivo index of ACE activity, was significantly reduced by estrogen treatment, further supporting the biochemical significance of estrogen's inhibition of ACE. In ovariectomized transgenic hypertensive (mRen2)27 rats submitted to estrogen replacement treatment for 3 weeks, ACE activity in plasma and tissue (aorta and kidney) and circulating Ang II levels were reduced, whereas circulating levels of angiotensin-(1-7) (Ang-(1-7)) were increased. Ang-(1-7), the N-terminal fragment of Ang II, is a novel vasodilator and antihypertensive peptide. Thus, the net balance of these effects of estrogen on the reninangiotensin vasoconstrictor/vasodilator system is to promote the anti-hypertensive effect.


Asunto(s)
Estrógenos/fisiología , Sistema Renina-Angiotensina/fisiología , Angiotensinas/análisis , Animales , Aorta Torácica/enzimología , Terapia de Reemplazo de Estrógeno , Femenino , Haplorrinos , Riñón/enzimología , Ovariectomía , Peptidil-Dipeptidasa A , Plasma/enzimología , Ratas , Vasoconstrictores/análisis
15.
Braz. j. med. biol. res ; 32(4): 373-81, Apr. 1999. ilus, tab, graf
Artículo en Inglés | LILACS | ID: lil-231726

RESUMEN

Estrogen stimulates the renin-angiotensin system by augmenting both tissue and circulating levels of angiotensinogen and renin. We show, however, that angiotensin converting enzyme (ACE) activity in the circulation and in tissues is reduced in two animal models of postmenopausal chronic hormone replacement. We observed a reduction of ACE activity in association with a significant increase in plasma angiotensin I (Ang I) and hyperreninemia in ovariectomized monkeys treated with Premarin (conjugated equine estrogen) replacement for 30 months. Plasma angiotensin II (Ang II) levels were not increased in monkeys treated with estrogen, suggesting that the decrease in ACE curtailed the formation of the peptide. The Ang II/Ang I ratio, an in vivo index of ACE activity, was significantly reduced by estrogen treatment, further supporting the biochemical significance of estrogen's inhibition of ACE. In ovariectomized transgenic hypertensive (mRen2)27 rats submitted to estrogen replacement treatment for 3 weeks, ACE activity in plasma and tissue (aorta and kidney) and circulating Ang II levels were reduced, whereas circulating levels of angiotensin-(1-7) (Ang-(1-7) were increased. Ang-(1-7), the N-terminal fragment of Ang II, is a novel vasodilator and antihypertensive peptide. Thus, the net balance of these effects of estrogen on the renin-angiotensin vasoconstrictor/vasodilator system is to promote the antihypertensive effect.


Asunto(s)
Animales , Femenino , Ratas , Estrógenos/metabolismo , Sistema Renina-Angiotensina/fisiología , Angiotensinas/análisis , Angiotensinas/efectos de los fármacos , Aorta Torácica/enzimología , Terapia de Reemplazo de Estrógeno , Estrógenos/farmacología , Haplorrinos , Riñón/enzimología , Ovariectomía , Peptidil-Dipeptidasa A , Plasma/enzimología , Sistema Renina-Angiotensina/efectos de los fármacos , Vasoconstrictores/análisis
16.
Proc Nutr Soc ; 58(4): 925-33, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10817160

RESUMEN

In the study of the regulation of skeletal muscle blood flow during exercise it is useful to obtain information regarding the concentrations of vasoactive substances in the muscle interstitium, a site where the compounds act on the vascular and skeletal muscle cells. The microdialysis technique is a useful tool for measuring interstitial substances in the muscle at rest and during exercise in human subjects, and the technique can also be used to study the effect of both systemic and local interventions in a specific area of an exercising muscle. Probe recovery, which represents the relative amount of a substance that is diffusing to the dialysis membrane, changes from rest to exercise and can be determined by the internal-standard technique which allows for a relatively high time resolution (min). Furthermore, the use of electrodes at the microdialysis outlet makes it possible to perform continuous measurements of interstitial substances. The present review gives examples of how the microdialysis technique has been applied to study potentially important vasodilators such as adenosine, NO and K+ in human skeletal muscles and highlights areas for future research to establish the functional importance of these compounds.


Asunto(s)
Espacio Extracelular/química , Microdiálisis , Contracción Muscular , Músculo Esquelético/fisiología , Vasoconstrictores/análisis , Vasodilatadores/análisis , Adenosina/análisis , Humanos , Concentración de Iones de Hidrógeno , Músculo Esquelético/irrigación sanguínea , Óxido Nítrico/análisis , Potasio/análisis
17.
Eur J Cardiothorac Surg ; 14(4): 367-72, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9845140

RESUMEN

OBJECTIVE: Peri-operative ischemic episodes following coronary artery bypass grafting with the internal mammary artery (IMA) are thought to be due to a vasospasm of this conduit. Endothelin-1 (ET-1) is a potent vasoconstrictor by itself and increases the response to other vasoconstrictor stimuli. This study focused on the possible role of an enhanced tissue ET-1-like immunoreactivity in the perioperative reaction of the IMA in patients with diabetes or hypercholesterolemia. METHODS: Specimens of the distal part of the IMA from 46 patients (mean age 58.5 years, four women, 42 men) were studied prospectively. Nine of those patients were diabetic and 26 had evidence of hypercholesterolemia. Another cohort of 20 IMA specimens was stained retrospectively; 10 of those biopsies were from patients that had experienced transient ischemic events peri-operatively in the myocardial area supplied by the IMA. The biopsies were examined histologically and immunohistochemically (rabbit polyclonal ET-1 antiserum, three-step avidin-biotin complex) with regard to their immunoreactivity to tissue ET-1. RESULTS: An immunoreactivity to ET-1 (graded 0-3) was present in 89% of the biopsies. The reactivity was significantly higher in patients with hypercholesterolemia ( 1.92+/-0.74) when compared to controls (1.0+/-0.63) (P = 0.04). The reactivity was also increased in patients with non-insulin-dependent diabetes mellitus (2.1+/-0.79), when compared to controls (P = 0.02). Mostly transient ischemic events in the area supplied by the IMA seemed to occur more frequently when the biopsies revealed a higher immunoreactivity to ET-1. They showed an increased reactivity to ET-1 (2.27+/-0.76) compared to 10 patients with an uneventful peri-operative course (1.66+/-0.71 ) (P = 0.04). CONCLUSIONS: This study provides evidence that the internal mammary artery is not a passive conduit. Vasospasm or vasoconstriction, in particular at its distal end, may occur more frequently in patients with hypercholesterolemia or diabetes, and may lead to post-operative ischemic events.


Asunto(s)
Circulación Coronaria , Diabetes Mellitus Tipo 2/metabolismo , Endotelina-1/análisis , Hipercolesterolemia/metabolismo , Anastomosis Interna Mamario-Coronaria , Arterias Mamarias/metabolismo , Biopsia , Estudios de Cohortes , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Femenino , Humanos , Inmunohistoquímica , Complicaciones Intraoperatorias , Masculino , Arterias Mamarias/patología , Persona de Mediana Edad , Isquemia Miocárdica/etiología , Isquemia Miocárdica/patología , Estudios Prospectivos , Estudios Retrospectivos , Vasoconstricción , Vasoconstrictores/análisis
18.
Rev. odontol. Univ. St. Amaro ; 3(2): 65-70, jul.-dez. 1998. ilus
Artículo en Portugués | LILACS, BBO - Odontología | ID: lil-247305

RESUMEN

Este trabalho teve por finalidade avaliar: a) os critérios utilizados pelos Cirurgiöes-Dentistas, Clínicos-Gerais, no emprego dos anestésicos locais em pacientes hipertensos controlados ou näo; b) cuidados que devem ser tomados pelos Profissionais na anamnese e no exame clínico para o diagnóstico desta patologia, bem como os cuidados adotados durante procedimentos clínicos de rotina. Questionários, padronizados em número aproximados de 200 (duzentos), foram preenchidos pelo pesquisador que entrevistou Cirurgiöes-Dentistas da regiäo Zona-Leste da grande Säo Paulo. Os resultados deste estudo mostraram que 75,0 por cento dos Cirurgiöes-Dentistas habitualmente näo realizam tomada da pressäo arterial. Para pacientes hipertensos, 60,38 por cento dos Cirurgiöes-Dentistas preferem utilizar anestésicos locais sem vasocontrictores


Asunto(s)
Vasoconstrictores/análisis , Vasoconstrictores/efectos adversos , Vasoconstrictores/farmacología , Anestésicos Locales/análisis , Anestésicos Locales/efectos adversos , Anestésicos Locales/farmacología , Pautas de la Práctica en Odontología , Hipertensión
19.
Crit Rev Clin Lab Sci ; 35(4): 275-368, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9759557

RESUMEN

Recent studies on human kallikrein 2 (hK2) have revealed striking similarities and significant differences with the closely related kallikrein PSA. Both PSA and hK2 are primarily localized to the prostate and share close structural similarities. Although both kallikreins are produced by the same secretory epithelial cells in the prostate, hK2 is associated more with prostate tumors than PSA and is highly expressed in poorly differentiated cancer cells. The potent trypsin-like activity of hK2 contrasts with the weak chymotrypsin-like activity of PSA. The inactive precursor form of PSA, proPSA, is converted rapidly to active PSA by hK2, suggesting an important in vivo regulatory function by hK2 on PSA activity. The high homology between hK2 and PSA results in significant cross-reactivity to hK2 by polyclonal and some monoclonal antibodies to PSA. Future studies on both PSA and hK2 need to take into account this potential for cross-reactivity. Specific monoclonal antibodies to hK2 have now demonstrated that serum levels of hK2, like PSA, are correlated with prostate cancer. The production of hK2 protein in active protease form and specific monoclonal antibodies to the hK2 antigen will allow extensive future studies delineating the physiological and clinical utility of this new prostate antigen.


Asunto(s)
Calicreínas/metabolismo , Antígeno Prostático Específico/metabolismo , Próstata/química , Vasoconstrictores/metabolismo , Humanos , Calicreínas/análisis , Calicreínas/genética , Masculino , Datos de Secuencia Molecular , Antígeno Prostático Específico/análisis , Antígeno Prostático Específico/genética , Neoplasias de la Próstata/metabolismo , Homología de Secuencia de Aminoácido , Calicreínas de Tejido , Vasoconstrictores/análisis
20.
J Histochem Cytochem ; 46(3): 301-11, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9487111

RESUMEN

In addition to the circulating renin-angiotensin system (RAS), a local system has been postulated in the anterior pituitary because immunodetection of its components in various mammalian species. However, different cell types appear to be involved in different species, and there is no general consensus on the subcellular localization of prorenin, renin and angiotensinogen. In this ultrastructural study, we investigated and quantified the presence of these components using double or triple immunogold labeling methods, in all the immunologically identified glandular cell types of the rat anterior pituitary. In contrast to previous reports, all these components were identified not only in lactotropes and gonadotropes but also in somatotropes, corticotropes, and thyrotropes. The highest levels were detected in lactotropes and gonadotropes, and renin gave the greatest signal. Angiotensinogen, prorenin, and renin were co-localized in the secretory granules of all rat pituitary glandular cell types. The simultaneous detection of the substrate (angiotensinogen) and both its specific cleavage enzyme and its proenzyme within the same granule suggests intragranular processing of this component. Moreover, the localization of these three constituents in the secretory granules also suggests that, in the rat anterior pituitary, they follow the regulated secretory pathway.


Asunto(s)
Angiotensina II/análisis , Gránulos Citoplasmáticos/química , Precursores Enzimáticos/análisis , Adenohipófisis/química , Renina/análisis , Hormona Adrenocorticotrópica/análisis , Animales , Hormona del Crecimiento/análisis , Inmunohistoquímica , Hormona Luteinizante/análisis , Masculino , Microscopía Inmunoelectrónica , Prolactina/análisis , Ratas , Ratas Wistar , Tirotropina/análisis , Vasoconstrictores/análisis
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