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1.
Hum Reprod ; 27(11): 3161-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22926840

RESUMO

STUDY QUESTION: How common is the use of herbal supplements during pregnancy and does it adversely affect the pregnancy outcome? SUMMARY ANSWER: The use of herbal products during pregnancy is very common and daily almond oil spreading is associated with preterm birth (PTB). WHAT IS KNOWN AND WHAT THIS PAPER ADDS: Herbal drugs are often promoted as 'natural' and 'safe' and such claims attract pregnant women. More than a quarter of Italian pregnant women consume herbs every day for at least 3 months during pregnancy. We raise an alert over the habit of daily almond oil spreading since it seems to be associated with PTB. DESIGN: A multicenter retrospective cohort study performed over a 15-month period. PARTICIPANTS AND SETTING: Seven hundred women interviewed within 3 days of childbirth, in three public hospitals in northern Italy. MAIN RESULTS AND ROLE OF CHANCE: One hundred and eighty-nine women were considered 'regular users', since they consumed herbs every day, for at least 3 months. Almond oil, chamomile and fennel were the most commonly used herbs. Both length of gestation and birthweight were affected by herb consumption. Almond oil users showed more pre-term birth (29 of 189) than non-users (51 of 511). After adjusting for multiple pregnancies, smoking, advanced age and drug intake, almond oil users maintained an increased risk to give birth <37th week (odds ratio = 2.09, 95% confidence interval: 1.08-4.08). BIAS, CONFOUNDING AND OTHER REASONS FOR CAUTION: The association between daily spreading of almond oil and PTB only raises a hypothesis that requires confirmation in larger trials devoted to this topic. The relatively small sample size did not allow the investigation of other adverse pregnancy outcomes in herb users. GENERALIZABILITY TO OTHER POPULATIONS: The population under investigation did not significantly differ from the general population attending the same hospitals. STUDY FUNDING/COMPETING INTEREST(S): No conflict of interest exists. The study has been supported by a public grant from the University of Modena and Reggio Emilia. TRIAL REGISTRATION NUMBER: None.


Assuntos
Suplementos Nutricionais/efeitos adversos , Preparações de Plantas/efeitos adversos , Plantas Medicinais/química , Nascimento Prematuro/etiologia , Autocuidado , Administração Tópica , Adulto , Peso ao Nascer , Camomila/efeitos adversos , Camomila/química , Estudos de Coortes , Suplementos Nutricionais/estatística & dados numéricos , Feminino , Foeniculum/efeitos adversos , Foeniculum/química , Hospitais Públicos , Humanos , Itália/epidemiologia , Óleos de Plantas/administração & dosagem , Óleos de Plantas/efeitos adversos , Preparações de Plantas/administração & dosagem , Plantas Medicinais/efeitos adversos , Gravidez , Nascimento Prematuro/epidemiologia , Estudos Retrospectivos , Risco , Fatores de Tempo
2.
Br J Anaesth ; 106(1): 13-22, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21148637

RESUMO

Previously undiagnosed anaemia is common in elective orthopaedic surgical patients and is associated with increased likelihood of blood transfusion and increased perioperative morbidity and mortality. A standardized approach for the detection, evaluation, and management of anaemia in this setting has been identified as an unmet medical need. A multidisciplinary panel of physicians was convened by the Network for Advancement of Transfusion Alternatives (NATA) with the aim of developing practice guidelines for the detection, evaluation, and management of preoperative anaemia in elective orthopaedic surgery. A systematic literature review and critical evaluation of the evidence was performed, and recommendations were formulated according to the method proposed by the Grades of Recommendation Assessment, Development and Evaluation (GRADE) Working Group. We recommend that elective orthopaedic surgical patients have a haemoglobin (Hb) level determination 28 days before the scheduled surgical procedure if possible (Grade 1C). We suggest that the patient's target Hb before elective surgery be within the normal range, according to the World Health Organization criteria (Grade 2C). We recommend further laboratory testing to evaluate anaemia for nutritional deficiencies, chronic renal insufficiency, and/or chronic inflammatory disease (Grade 1C). We recommend that nutritional deficiencies be treated (Grade 1C). We suggest that erythropoiesis-stimulating agents be used for anaemic patients in whom nutritional deficiencies have been ruled out, corrected, or both (Grade 2A). Anaemia should be viewed as a serious and treatable medical condition, rather than simply an abnormal laboratory value. Implementation of anaemia management in the elective orthopaedic surgery setting will improve patient outcomes.


Assuntos
Anemia/diagnóstico , Procedimentos Ortopédicos , Cuidados Pré-Operatórios/métodos , Algoritmos , Anemia/complicações , Anemia/terapia , Procedimentos Cirúrgicos Eletivos , Humanos , Procedimentos Ortopédicos/efeitos adversos
3.
Cancer Res ; 52(3): 623-30, 1992 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-1732050

RESUMO

The potentiation of monoclonal antibody/ligand toxin (immunotoxin) cytotoxicity by the ionophore monensin (Mo) or by human serum albumin-monensin (HSA-Mo) conjugates was investigated. Since disulfide cross-linked HSA-Mo (HSA-SPDP-Mo) is rapidly inactivated by human serum (M. Colombatti et al., Cancer Res., 50: 1385-1391, 1990), we synthesized thioether cross-linked HSA-Mo conjugates (HSA-SIA-Mo). HSA-SIA-Mo is resistant to treatment with reducing agents (e.g., glutathione, dithiothreitol) and shows potentiating activity identical to that of Mo or of HSA-SPDP-Mo, enhancing immunotoxin (IT) cytotoxicity 45-35,000-fold. Human leukemic and tumor cell lines are highly sensitive to treatment with IT in combination with Mo, HSA-SPDP-Mo, or HSA-SIA-Mo (concentration required to inhibit protein synthesis by 50%, 10(-10)-2.5 x 10(-13) M). IT potentiation by both types of HSA-Mo conjugates, however, is inhibited by whole human serum. In contrast, human cerebrospinal fluid has no effect on the potentiation of IT by Mo or HSA-Mo conjugates. The serum blocking factors reside mostly in a Mr 40,000-90,000 protein fraction. Serum components of low molecular weight (less than 10,000) show no detectable effect upon the stability of HSA-Mo conjugates. The toxicity of HSA-SIA-Mo in vivo was investigated by intrathecal injections in rats. Concentrations of up to 60 micrograms/kg can be injected into the brain with only transient neurological sequelae. We therefore conclude that if the systemic delivery of HSA-Mo conjugates for the potentiation of ricin A chain-IT presents some limitations due to the blocking effect of serum, the application of HSA-Mo conjugates in combination with ricin A chain-IT for regional tumor therapy in the brain appears more promising.


Assuntos
Fenômenos Fisiológicos Sanguíneos , Sobrevivência Celular/efeitos dos fármacos , Líquido Cefalorraquidiano/fisiologia , Imunotoxinas/toxicidade , Monensin/farmacologia , Ricina/toxicidade , Albumina Sérica/farmacologia , Cloreto de Amônio/farmacologia , Animais , Linhagem Celular , Reagentes de Ligações Cruzadas , Dissulfetos/metabolismo , Ditiotreitol/farmacologia , Sinergismo Farmacológico , Humanos , Cinética , Monensin/toxicidade , Ratos , Albumina Sérica/toxicidade , Succinimidas
4.
Thromb Haemost ; 76(5): 791-8, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8950792

RESUMO

We studied in vitro the antiplatelet activity of a new nitroderivative chemically related to acetylsalicylic acid: 2 acetoxybenzoate 2-[1-nitroxy-methyl]-phenyl ester (NCX 4016), in order to identify any effects due to the release of nitric oxide and the blockade of cyclo-oxygenase. The effects of scalar doses of NCX 4016 on the early phase of platelet activation, platelet aggregation and thromboxane A2 production were investigated. We observed inhibitory effects of NCX 4016 on platelet adhesion (IC50 = 7.3 x 10(-5) M), platelet cytosolic calcium concentration, assayed by fluorescent probe Fura 2, and the expression of glycoprotein IIb/IIIa (CD41/alpha IIb beta 3) (IC50 = 3.4 x 10(-5) M) and P-selectin (CD62/GMP-140) (IC50 = 4.9 x 10(-5) M) measured by flow cytometry. NCX 4016 also prevented thrombin-induced platelet aggregation (IC50 = 3.9 x 10(-5) M). None of these parameters were affected by acetylsalicylic acid. These inhibitory activities of NCX 4016 were abolished by oxyhaemoglobin and methylene blue. Intracellular cyclic GMP observed during thrombin-induced aggregation was increased by incubation with NCX 4016. These results appear to be attributable to the release of nitric oxide, which activates soluble platelet guanylylcyclase and promotes intracellular cyclic GMP increase. NCX 4016 almost completely inhibited platelet thromboxane A2 production and arachidonic acid-induced platelet aggregation. This also occurred in the presence of oxyhaemoglobin and methylene blue, indicating that its antiplatelet activity can be attributed not only to nitric oxide release but also to cyclo-oxygenase inhibition.


Assuntos
Aspirina/análogos & derivados , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Tromboxano A2/biossíntese , Adulto , Aspirina/farmacologia , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Cálcio/sangue , GMP Cíclico/sangue , Humanos , Selectina-P/biossíntese , Adesividade Plaquetária/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/biossíntese
5.
Thromb Haemost ; 78(3): 993-6, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9308742

RESUMO

Resistance to activated protein C (APC) caused by the R506Q mutation in factor V is the most common inherited risk factor for venous thrombosis. To elucidate whether APC-resistance is a risk factor for venous thrombosis after elective total hip replacement, the association between APC-resistance (presence of FV:Q506 allele) and postoperative thrombosis was investigated in patients (n = 198) randomised to received short (during hospitalisation, n = 100) or prolonged prophylaxis (three weeks after hospitalisation, n = 98) with low molecular weight heparin (LMWH). Among APC-resistant individuals receiving short prophylaxis, 7/10 developed thrombosis as compared to 2/12 receiving long prophylaxis (p <0.0179). Odds ratio for association between APC-resistance and thrombosis in the short prophylaxis group was 4.2 (CI 95% 1.02-17.5) (p <0.0465). Among those receiving prolonged prophylaxis, there was no increased incidence of thrombosis associated with APC-resistance. Two unexpected observations were made. One was that APC-resistance was much more common in women (19/109) than in men (3/89) (p <0.001). The other was that even women without APC-resistance were much more thrombosis-prone than men. Thus, 24/48 of women with normal FV genotype and short prophylaxis developed thrombosis vs 8/42 among men, p = 0.002. The increased risk of thrombosis associated with female gender and APC-resistance was neutralised by the prolonged treatment. In conclusion, among patients receiving short prophylaxis, female gender was found to be a strong risk factor for venous thrombosis. Even though APC-resistance appeared to be a risk factor for postoperative thrombosis, the uneven distribution of APC-resistance between men and women, taken together with the increased risk of thrombosis among women, precluded valid conclusions to be drawn about the association between APC-resistance and an increased risk of thrombosis. Our results suggest that prolonged prophylaxis with LMWH after hip surgery is more important for women than for men.


Assuntos
Artroplastia de Quadril/efeitos adversos , Fator V/genética , Proteína C/fisiologia , Caracteres Sexuais , Tromboflebite/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Resistência a Medicamentos/genética , Feminino , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Fatores de Risco
6.
Br J Pharmacol ; 116(2): 1713-4, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8528547

RESUMO

Nitroflurbiprofen (NFP) causes significantly less gastric lesions than flurbiprofen (FP), probably because of its capacity to release nitric oxide (NO) in the stomach. Lipopolysaccharide (LPS), which induces the expression of an inducible type of NO synthase (iNOS) in rat stomach, also reduces gastric mucosal damage elicited by FP. Furthermore, both FP and NFP decrease significantly the amount of mRNA encoding iNOS induced by LPS in the stomach. The inhibitory effect of NFP seems to be due at least in part to its ability to release NO.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Flurbiprofeno/análogos & derivados , Flurbiprofeno/farmacologia , Óxido Nítrico/metabolismo , Estômago/efeitos dos fármacos , Animais , Feminino , Óxido Nítrico Sintase/efeitos dos fármacos , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley
7.
Br J Pharmacol ; 114(6): 1105-6, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7542530

RESUMO

A well-known nitric oxide (NO)-releasing compound, sodium nitroprusside (SNP), decreases in a dose-dependent manner NO synthase (NOS) activity induced in rat neutrophils by treatment with lipopolysaccharide (LPS). This inhibitory action of SNP seems not to be due to its direct effect on the enzyme activity. The strong nitrosonium ion (NO+) character of SNP could be responsible for its inhibition of NOS induction in neutrophils.


Assuntos
Aminoácido Oxirredutases/biossíntese , Neutrófilos/efeitos dos fármacos , Nitroprussiato/farmacologia , Animais , Relação Dose-Resposta a Droga , Indução Enzimática/efeitos dos fármacos , Feminino , Lipopolissacarídeos/farmacologia , Neutrófilos/enzimologia , Óxido Nítrico Sintase , Ratos , Ratos Sprague-Dawley
8.
Br J Pharmacol ; 115(2): 225-6, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7545516

RESUMO

The effects of a non-steroidal anti-inflammatory drug, flurbiprofen, and its nitro-derivative, nitroflurbiprofen, on inducible nitric oxide synthase in rat neutrophils were examined. Nitroflurbiprofen was shown to inhibit nitric oxide synthase induction caused by lipopolysaccharide administration, while flurbiprofen had no effect on nitric oxide synthase induction. This inhibitory action may be ascribed to nitric oxide released from nitroflurbiprofen.


Assuntos
Aminoácido Oxirredutases/biossíntese , Anti-Inflamatórios não Esteroides/farmacologia , Flurbiprofeno/análogos & derivados , Flurbiprofeno/farmacologia , Neutrófilos/efeitos dos fármacos , Administração Oral , Análise de Variância , Animais , Separação Celular , Centrifugação com Gradiente de Concentração , Indução Enzimática/efeitos dos fármacos , Feminino , Lipopolissacarídeos/toxicidade , Neutrófilos/enzimologia , Nitratos/sangue , Óxido Nítrico Sintase , Nitritos/sangue , Ratos , Ratos Sprague-Dawley
9.
Thromb Res ; 85(3): 195-206, 1997 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9058494

RESUMO

The aim of the present study was to investigate aspects of coagulation and fibrinolysis during knee arthroplasties in order to find out. 1. whether an increased fibrinolysis is correlated to an increased blood loss 2. whether there is a difference in markers for coagulation and fibrinolysis in peripheral venous blood compared to those in blood from the wounds 3. whether the administration of tranexamic acid modifies the fibrinolytic response. Twenty-four patients were included. Twelve patients were given tranexamic acid intravenously at the end of the operation. The dose was repeated three hours later. The other 12 patients were given an equivalent amount of placebo. The administration was randomised and double-blind. Levels of prothrombin fragments 1 + 2, D-dimers, plasminogen, alpha 2-antiplasmin, tissue plasminogen activator (tPA), and plasminogen activator inhibitor (PAI-1) in venous blood were investigated just before the operation, at the end of the operation and three hours later. At the end of the operation blood for analysis was also drawn from the wound. Coagulation and fibrinolysis was activated during and after surgery. The activation was significantly higher in blood from the wounds than in peripheral venous blood. We found no direct correlation between the degree of fibrinolysis and blood loss. The administration of tranexamic acid reduced fibrinolysis in the wounds but not in peripheral venous blood. The postoperative blood loss was reduced by half.


Assuntos
Antifibrinolíticos/farmacologia , Fibrinólise/efeitos dos fármacos , Complicações Intraoperatórias/sangue , Prótese do Joelho , Ácido Tranexâmico/farmacologia , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Humanos , Complicações Intraoperatórias/prevenção & controle , Masculino
10.
Thromb Res ; 99(5): 429-38, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10973670

RESUMO

The aim was to describe the phlebographic pattern of asymptomatic and symptomatic deep vein thrombosis (DVT) after total hip replacement by the use of a scoring system in 102 consecutive patients (54 asymptomatic, 48 symptomatic). The DVTs were scored from 1 to 3, and registered in a scoring system dividing the deep veins into 12 separate segments. The asymptomatic patients had a significantly lower total mean DVT score of 3.7 compared to 9.1 in the symptomatic group of patients. The mean ratio of the DVT scores in the deep muscle veins in conjunction with the superficial femoral vein in relation to the total mean score was significantly higher in the asymptomatic patients (74.9%) compared to the symptomatic group (62.4%). A direct sign of DVT, displayed as a filling defect, was seen on the phlebogram in 116 of the 119 legs, and concomitant nonfilling in other vein segments was noted in 6% of the asymptomatic patients, while in the symptomatic group this was the case to a significantly higher level, namely, 46%. A subgroup of asymptomatic patients operated unilaterally, with bilateral DVT had a significantly higher total mean DVT score on the operated side (4. 6) compared to the unoperated side (3.4). The total mean DVT score increased with time after surgery in the group of symptomatic patients. A low total mean DVT score with a predominance of DVT in, or in the connection to, the deep muscle veins is displayed among the asymptomatic patients. This is significantly different from the symptomatic patients who have more extensive DVTs, especially when diagnosed several weeks postoperatively, and frequently with edema and occlusive DVT.


Assuntos
Artroplastia de Quadril/efeitos adversos , Trombose Venosa , Trombose Venosa/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas de Diagnóstico Cardiovascular , Feminino , Humanos , Perna (Membro)/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Flebografia/métodos , Índice de Gravidade de Doença , Trombose Venosa/etiologia
11.
Thromb Res ; 80(5): 367-76, 1995 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-8588198

RESUMO

We studied in vitro the effects on platelet aggregation and vascular tone of a new nitrocompound (nitroxy-butyl-acetylsalicylate: NO-ASA). In order to elucidate any possible activity due to the release of nitric oxide or the inhibition of platelet cyclo-oxygenase we compared NO-ASA to acetylsalicylic acid. NO-ASA 1 mM inhibited arachidonic acid-induced platelet aggregation (basal 75.4 +/- 2.35%; NO-ASA 22 +/- 3.46%; M +/- SEM; P < 0.001; n = 6), but proved less active than acetylsalicylic acid (complete inhibition at 2 x 10(-5) M). NO-ASA also significantly reduced thrombin-induced (0.04-0.08 U/ml) platelet aggregation in acetylsalicylic acid-treated platelets (basal 70.5 +/- 1.7%; NO-ASA 35.4 +/- 2.2%; P < 0.001; n = 10; IC50 7 x 10(-5) M). Methylene blue reduced the effects of NO-ASA on thrombin-induced (NO-ASA 46.7 +/- 5.25%; NO-ASA+MB 59.1 +/- 4.3%; P < 0.01; n = 8), but not arachidonic acid-induced platelet aggregation. The inhibitory effects of NO-ASA on platelet aggregation were partially removed by oxyhaemoglobin. Platelet thromboxane A2 production (TXB2 concentration in the supernatant of the aggregate 35.38 +/- 7.81 ng/ml; n = 8), was totally abolished by acetylsalicylic acid (0.17 +/- 0.04 ng/ml; P < 0.001; n = 8) and reduced by NO-ASA (8.3 +/- 4.05 ng/ml; P < 0.01; n = 8). In vitro studies on isolated rat aortic rings showed NO-ASA 10(-3) M, but not ASA up to 10(-3) M, induce a dose dependent vasorelaxation (100% of epinephrine-induced contraction) both in intact and endothelium denuded arteries (IC50 5 x 10(-5) M). Addition of methylene blue reversed this relaxation. In conclusion these data demonstrate that NO-ASA acts through a double mechanism: a) by inhibiting cyclo-oxygenase and b) by releasing NO active on guanylyn cyclase both in platelets and in vascular smooth muscle cells.


Assuntos
Aspirina/análogos & derivados , Músculo Liso Vascular/fisiologia , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Adulto , Animais , Aorta Torácica , Ácido Araquidônico/antagonistas & inibidores , Aspirina/farmacologia , Feminino , Humanos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Ratos , Ratos Sprague-Dawley , Trombina/antagonistas & inibidores , Tromboxano A2/biossíntese
12.
Life Sci ; 58(11): PL207-10, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8786689

RESUMO

The effects of a new ASA-nitroderivative compound, NCX 4016 (ASA-NO2), on platelet TXA2 synthesis after single and repeated doses in the rat were investigated. Compared to ASA, cumulative doses of ASA-NO2 showed similar inhibitory effects on platelet TXA2 synthesis and significant increases in nitrite/nitrate plasma concentrations 1 h after the last drug administration: 24 h later nitrite/nitrate plasma levels returned to the control values, while serum TXA2 concentrations did not change. A time-course study after a single dose of ASA-NO2 showed a significant inhibition of platelet TXA2 production also 24 h after drug administration and a significant increase in nitrite/nitrate plasma levels until 10 h.


Assuntos
Aspirina/farmacologia , Plaquetas/efeitos dos fármacos , Tromboxano A2/metabolismo , Animais , Aspirina/análogos & derivados , Plaquetas/metabolismo , Relação Dose-Resposta a Droga , Feminino , Nitritos/sangue , Ratos , Ratos Sprague-Dawley , Tromboxano B2/sangue
13.
Life Sci ; 60(2): 101-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9000115

RESUMO

The pharmacokinetics of a new ASA-nitroderivative compound, NCX 4016 (ASA-NO2), was evaluated using an HPLC method. After single equimolar doses of ASA (35 mg kg(-1)) or ASA-NO2 (65 mg kg(-1)), no detectable levels of these compounds have been observed in rat plasma samples. SA peak levels were obtained at 3 h and 6 h after ASA and ASA-NO2 administration respectively. The elimination rate constants of SA were similar after ASA and ASA-NO2, suggesting a similar elimination phase of this metabolite in rats. From these data it is evident that ASA-NO2 is slowly metabolized in ASA, which is rapidly converted to SA.


Assuntos
Aspirina/farmacocinética , Animais , Aspirina/administração & dosagem , Aspirina/sangue , Cromatografia Líquida de Alta Pressão , Feminino , Ratos , Ratos Sprague-Dawley
14.
Life Sci ; 69(3): 335-46, 2001 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-11441924

RESUMO

We have studied the pharmacokinetics of an anti-transferrin receptor immunotoxin following intrathecal (i.t.) and intravenous (i.v.) bolus inoculation in healthy rats. After i.t. inoculation of 4.9 microg transferrin-ricin A-chain (Tfn-RTA) we have measured the immunotoxin concentration in the cerebrospinal fluid (CSF), in the brain tissue and in the peripheral blood. After i.v. administration of 4.9 microg Tfn-RTA the concentration of Tfn-RTA immunotoxin was evaluated in the peripheral blood. We found that the clearance of Tfn-RTA from the CSF is rapid (9.1 microLmin(-1)), the immunotoxin then diffuses into the brain tissue and in the peripheral blood where it reaches concentrations below the MTC50 (Minimum Toxin Concentration 50%). The rate of immunotoxin elimination from the peripheral blood following either i.v. or i.t. administration are similar (kel = 0.0021 min(-1) vs. 0.0025 min(-1)). Thus, in the healthy rat the immunotoxin does not accumulate following i.t. inoculation, reaching non toxic concentrations in the brain tissue and in the peripheral blood, whereas in the CSF as well as at the interface CSF/brain tissue the immunotoxin may reach potentially therapeutic concentrations. In conclusion we believe that the i.t. inoculation of an immunotoxin could be considered a potentially useful route of administration in the treatment of leptomeningeal carcinomatosis.


Assuntos
Imunotoxinas/farmacocinética , Receptores da Transferrina/imunologia , Ricina/imunologia , Animais , Área Sob a Curva , Sobrevivência Celular/efeitos dos fármacos , Meia-Vida , Humanos , Imunotoxinas/administração & dosagem , Imunotoxinas/líquido cefalorraquidiano , Imunotoxinas/toxicidade , Injeções Intravenosas , Injeções Espinhais , Células Jurkat/efeitos dos fármacos , Células Jurkat/metabolismo , Ratos , Ricina/toxicidade
15.
Life Sci ; 63(23): 2097-105, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9839533

RESUMO

Previous studies have shown a role for nitric oxide (NO) as a cytotoxic effector. In the present work, two chemically different NO-donors such as glyceryl trinitrate (GTN) and S-nitroso-N-acetylpenicillamine (SNAP) were evaluated for both NO release and cytostatic/cytotoxic properties. Nitrite accumulation in the supernatant of MCF-7 and U251 cell lines indicated a greater and quickly release of NO derived from SNAP. A time-course of hemoglobin absorption spectral changes showed a greater release of NO derived from GTN in presence of cells compared to the values observed in the media, confirming that the release of NO by GTN can be enzymatic and non-enzymatic. On the contrary, SNAP generated NO without contribution of cellular components and saturated oxyhemoglobin quickly, within 2 hours. Both NO-donors inhibited thymidine incorporation in a similar manner and dose-dependently in U251 cells, but not in MCF-7 cells, where SNAP at the highest tested dose of 1000 microM induced only a 33% cytostatic effect. About trypan blue exclusion test, after 24 h GTN and SNAP, releasing similar amounts of NO, showed comparable cytotoxic effects on U251 cells (50% dead cells), but not on MCF-7 cells, where GTN resulted more cytotoxic. From our data, the "in vitro" antitumoral activity of NO-donors seems to be related to the type of tumor cell lines, to the amount and duration of NO release.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/toxicidade , Doadores de Óxido Nítrico/toxicidade , Óxido Nítrico/metabolismo , Nitroglicerina/toxicidade , Penicilamina/análogos & derivados , Biotransformação , Neoplasias Encefálicas/patologia , Neoplasias da Mama/patologia , Inibidores Enzimáticos/farmacocinética , Feminino , Glioblastoma/patologia , Humanos , Cinética , Doadores de Óxido Nítrico/farmacocinética , Nitroglicerina/farmacocinética , Penicilamina/farmacocinética , Penicilamina/toxicidade , S-Nitroso-N-Acetilpenicilamina , Células Tumorais Cultivadas
16.
Life Sci ; 65(26): 2815-22, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10622270

RESUMO

The effects of 14-day physical exercise or iloprost treatment (0.5-2 ng/Kg/min) on endogenous nitric oxide production and neutrophil adhesion were evaluated in 20 patients with peripheral arterial occlusive disease (Fontaine Stage II). Peripheral venous blood samples and 4-h urine samples were collected before, immediately after 14 days of therapy and 7-10 days after therapy in order to evaluate neutrophil adhesion, nitrite/nitrate and cGMP excretion rates. A longer pain free walking distance was observed after exercise, compared to iloprost (>500 m in 3/10 subjects). Urinary nitrite/nitrate, as well as cGMP concentrations, significantly increased after exercise. Nitrite/nitrate excretion rate inversely correlated to neutrophil adhesion. No variations were observed in these parameters in iloprost treated patients. The improvement in claudication and the transient increase in urinary nitrite/nitrate suggest a possible nitric oxide-dependent mechanism for the clinical efficacy of physical exercise. The results from the present and previous observations indicate that, besides pharmacological treatments, a regular aerobic exercise improves peripheral arterial occlusive disease.


Assuntos
Arteriopatias Oclusivas/metabolismo , Arteriopatias Oclusivas/fisiopatologia , Terapia por Exercício , Óxido Nítrico/biossíntese , Doenças Vasculares Periféricas/metabolismo , Doenças Vasculares Periféricas/fisiopatologia , Idoso , Arteriopatias Oclusivas/terapia , Adesão Celular/efeitos dos fármacos , Humanos , Iloprosta/uso terapêutico , Infusões Intravenosas , Pessoa de Meia-Idade , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Nitratos/urina , Óxido Nítrico/metabolismo , Nitritos/urina , Doenças Vasculares Periféricas/terapia , Vasodilatadores/uso terapêutico
17.
J Pharm Sci ; 90(9): 1226-41, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11745776

RESUMO

The aim of this study was to predict the disposition of midazolam in individual surgical patients by physiologically based pharmacokinetic (PBPK) modeling and explore the causes of interindividual variability. Tissue-plasma partition coefficients (k(p)) were scaled from rat to human values by a physiologically realistic four-compartment model for each tissue, incorporating the measured unbound fraction (f(u)) of midazolam in the plasma of each patient. Body composition (lean body mass versus adipose tissue) was then estimated in each patient, and the volume of distribution at steady state (V(dss)) of midazolam was calculated. Total clearance (CL) was calculated from unbound intrinsic CL, f(u), and estimated hepatic blood flow. Curves of midazolam plasma concentration versus time were finally predicted by means of a perfusion-limited PBPK model and compared with measured data. In a first study on 14 young patients undergoing surgery with modest blood loss, V(dss) was predicted with an only 3.4% mean error (range -24-+39%) and a correlation between predicted and measured values of 0.818 (p < 0.001). Scaling of k(p) values by the four-compartment model gave better predictions of V(dss) than scaling using unbound k(p). In the PBPK modeling, the mean +/- standard deviation (SD) prediction error for all data was 9.7 +/- 33%. In a second study with 10 elderly patients undergoing orthopedic surgery, hemodilution and blood loss led to a higher f(u) of midazolam. The PBPK modeling correctly predicted a marked increase in V(dss), a smaller increase in CL, and a prolonged terminal half-life of midazolam, as compared with findings in the first study. Interindividual variation in the disposition of midazolam could thus in part be related to the physiological characteristics of the patients and the f(u) of the drug in their plasma.


Assuntos
Adjuvantes Anestésicos/farmacocinética , Midazolam/farmacocinética , Modelos Biológicos , Pacientes/estatística & dados numéricos , Adjuvantes Anestésicos/sangue , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Animais , Humanos , Masculino , Midazolam/sangue , Pessoa de Meia-Idade , Ratos , Estatísticas não Paramétricas , Distribuição Tecidual/fisiologia
18.
J Pharm Sci ; 84(1): 93-5, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7714752

RESUMO

An accurate and sensitive HPLC method has been developed for the determination of nitrofenac, a new, original diclofenac derivate showing a good tolerability and a wide anti-inflammatory profile, diclofenac, and its metabolites in plasma. This method has been applied to evaluate the pharmacokinetic parameters of the drugs, using a noncompartmental model, after the oral administration of 5 mg/kg nitrofenac to rats. Nitrofenac and the internal standard flufenamic acid were dissolved in acetonitrile, and diclofenac was dissolved in methanol. The drugs were eluted from a 5 microns LC-8 column with a mobile phase consisting of acetonitrile/water (50/50 v/v) adjusted to pH 3.3 with glacial acetic acid, at a flow rate of 2 mL/min with UV detection at 280 nm for diclofenac and 275 nm for nitrofenac. The detection limit for the drugs in plasma was 25 ng/mL. The peak concentration of nitrofenac was reached 7 h after drug administration, while with diclofenac we observed three peaks at 2, 5, and 10 h; the mean residence time and the elimination rate constant for nitrofenac were 6.18 +/- 0.09 h and 0.37 +/- 0.03 h-1 respectively, while those for diclofenac were 12.24 +/- 0.11 h and 0.11 +/- 0.04 h-1. Under our conditions, the metabolism of nitrofenac produced 23% diclofenac and other metabolites: the plasma concentrations and kinetic characteristics of diclofenac are enough to induce an anti-inflammatory activity, while the clinical importance of the other metabolites remains to be elucidated.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Diclofenaco/análogos & derivados , Animais , Anti-Inflamatórios não Esteroides/sangue , Cromatografia Líquida de Alta Pressão , Diclofenaco/sangue , Diclofenaco/farmacocinética , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Masculino , Ratos , Ratos Sprague-Dawley , Espectrofotometria Ultravioleta
19.
Ultrasound Med Biol ; Suppl 2: 223-7, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6400243

RESUMO

Airborne ultrasound has been utilized for remote measurement of distance, direction, size, form, volume and velocity. General anthropometrical measurements are performed with a newly constructed real-time linear array scanner. To make full use of the method, we expect a rapid development of high-frequency ultrasound transducers for use in air.


Assuntos
Antropometria/instrumentação , Ultrassonografia/instrumentação , Engenharia Biomédica , Fenômenos Biofísicos , Biofísica , Humanos
20.
Ultrasound Med Biol ; 17(5): 519-28, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1962355

RESUMO

Diagnostic ultrasound is an established, noninvasive and harmless method for imaging the shape and appearance of organs and other tissues inside the body, and it has been used in many clinical applications for more than three decades. We have now applied some of this well-known technique together with the use of airborne ultrasound in medical applications, to build an equipment for anthropometrical investigation outside the body, e.g., measuring and registration of the shape and form of the human back. This is mostly done for screening purposes of young people in an attempt to find patients developing scoliosis, and in order to circumvent some of the disadvantages with the traditional screening method in this field of medical application.


Assuntos
Escoliose/diagnóstico por imagem , Ultrassonografia/instrumentação , Dorso/diagnóstico por imagem , Humanos , Programas de Rastreamento/instrumentação , Topografia de Moiré , Escoliose/prevenção & controle , Transdutores , Ultrassonografia/métodos
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