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1.
Int J Nanomedicine ; 13: 3625-3640, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29983558

RESUMO

BACKGROUND: Lumbrokinase (LK) is an enzyme complex with antithrombotic, antioxidant, antitumor, and immunomodulatory effects. It has been extensively studied and used in clinical anti-tumor therapy. However, its half-life is short, its bioavailability is low, and its toxicity and side effects are great, which greatly limit its clinical application. Therefore, LK is often combined with other drugs (such as immune agents, hormones, or Chinese herbal medicine) to reduce its dosage and side effects and to improve its anti-tumor effects. METHODS AND RESULTS: Here, we described an LK/paclitaxel (PTX) nanocarrier based on poly(ethylene glycol)-b-(poly(ethylenediamine l-glutamate)-g-poly(ε-benzyoxycarbonyl-l-lysine)-r-poly(l-lysine)) (PEG-b-(PELG-g-(PZLL-r-PLL))). In the present study, LK and PTX were loaded by electrostatic and/or hydrophobic effects under mild conditions, thereby increasing the half-life and bioavailability of the drugs via the sustained release and enhancement of tumor site enrichment by the LK/PTX/PEG-b-(PELG-g-(PZLL-r-PLL)) complex through passive targeting. In this study, using bladder cancer cells (J82 cells) and rat bladder cancer model as the object, the structure of the nanocarrier, the relationship between drugs composition and antitumor properties were systematically studied. CONCLUSION: We propose that the block copolymer PEG-b-(PELG-g-(PZLL-r-PLL)) may function as a potent nanocarrier for augmenting anti-bladder cancer pharmacotherapy, with unprecedented clinical benefits.


Assuntos
Albuminas/uso terapêutico , Endopeptidases/uso terapêutico , Paclitaxel/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Albuminas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclina B1/metabolismo , Portadores de Fármacos/química , Endopeptidases/sangue , Endopeptidases/farmacologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lisina/análogos & derivados , Lisina/síntese química , Lisina/química , Masculino , Microvasos/patologia , Peso Molecular , Paclitaxel/sangue , Paclitaxel/farmacologia , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Polilisina/análogos & derivados , Polilisina/síntese química , Polilisina/química , Ratos Sprague-Dawley , Carga Tumoral/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Neoplasias da Bexiga Urinária/sangue , Neoplasias da Bexiga Urinária/irrigação sanguínea , Neoplasias da Bexiga Urinária/patologia
2.
Methods Mol Biol ; 1646: 217-225, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28804832

RESUMO

Direct oral anticoagulants (DOACs) can be quantified using methods that can be performed in any clinical or research laboratory using manual or automated instrument platforms. Dabigatran etexilate, the oral direct thrombin inhibitor, can be quantified by drug-calibrated clot or chromogenic-based assays using either thrombin or ecarin as substrates. Oral direct anti-Xa inhibitors, such as rivaroxaban, apixaban, and edoxaban, can be quantified with drug-calibrated anti-Xa kits or reagents as typically used for measuring heparins (unfractionated, low molecular weight, or pentasaccharides).


Assuntos
Antitrombinas/sangue , Antitrombinas/uso terapêutico , Monitoramento de Medicamentos/métodos , Inibidores do Fator Xa/sangue , Inibidores do Fator Xa/uso terapêutico , Tempo de Trombina/métodos , Administração Oral , Antitrombinas/administração & dosagem , Coagulação Sanguínea/efeitos dos fármacos , Dabigatrana/administração & dosagem , Dabigatrana/sangue , Dabigatrana/uso terapêutico , Endopeptidases/administração & dosagem , Endopeptidases/sangue , Endopeptidases/uso terapêutico , Inibidores do Fator Xa/administração & dosagem , Fibrinolíticos/administração & dosagem , Fibrinolíticos/sangue , Fibrinolíticos/uso terapêutico , Humanos , Pirazóis/administração & dosagem , Pirazóis/sangue , Pirazóis/uso terapêutico , Piridinas/administração & dosagem , Piridinas/sangue , Piridinas/uso terapêutico , Piridonas/administração & dosagem , Piridonas/sangue , Piridonas/uso terapêutico , Rivaroxabana/administração & dosagem , Rivaroxabana/sangue , Rivaroxabana/uso terapêutico , Tiazóis/administração & dosagem , Tiazóis/sangue , Tiazóis/uso terapêutico , Tromboembolia Venosa/sangue , Tromboembolia Venosa/tratamento farmacológico
3.
Horm Metab Res ; 46(8): 561-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24627106

RESUMO

The renin-angiotensin system (RAS), vasopressin, and nitric oxide (NO) interact to regulate blood pressure at central and peripheral level. To improve our understanding of their interaction and their relationship with the hypothalamus and the cardiovascular system, we analyzed angiotensin- and vasopressin-metabolizing activities in hypothalamus (HT), left ventricle (LV), and plasma, collected from Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) treated or not with L-NAME [N(G)-nitro-L-arginine methyl ester], which inhibits the formation of NO and over-activates the sympathetic nervous system. Previous observations in WKY suggested higher formation of Ang III and Ang IV in the HT and higher availability of Ang II in plasma after L-NAME treatment. Our current results show higher formation of Ang IV and higher metabolism of vasopressin after treatment with L-NAME in the LV of WKY rats. In SHR treated with L-NAME, there is higher availability of Ang III in the HT leading to higher release of vasopressin together with lower formation of Ang 2-10. In their LV, however, there is an increase of vasopressinase. Interestingly, while the enzymatic activities in the HT and LV of WKY rats and control SHR are poorly correlated, they are well but inversely correlated in the L-NAME treated SHR. On the other hand, no significant correlations between enzymatic activities in HT or LV and plasma were noticed. Our results suggest that eNOS inhibition in SHR induces or enhances an inverse reciprocal interaction between HT and LV involving the RAS and vasopressin, which may be mediated by the autonomic nervous system.


Assuntos
Cistinil Aminopeptidase/sangue , Endopeptidases/sangue , Hipotálamo/enzimologia , Miocárdio/enzimologia , NG-Nitroarginina Metil Éster/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Sistema Renina-Angiotensina/efeitos dos fármacos , Solubilidade
4.
Horm Metab Res ; 44(2): 152-4, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22203440

RESUMO

Reducing angiotensin II (Ang II) production via angiotensin-converting enzyme (ACE) inhibitors is a key approach for the treatment of hypertension. However, these inhibitors may also affect other enzymes, such as angiotensinases and vasopressinase, responsible for the metabolism of other peptides also involved in blood pressure control, such as Ang 2-10, Ang III, Ang IV, and vasopressin. We analyzed the activity of these enzymes in the hypothalamus, plasma, and kidney of normotensive adult male rats after inhibition of ACE with captopril. Aspartyl- (AspAP), glutamyl- (GluAP), alanyl- (AlaAP) and cystinyl-aminopeptidase (CysAP) activities were measured fluorimetrically using arylamides as substrates. Systolic blood pressure (SBP), water intake, and urine flow were also measured. Captopril reduced SBP and increased urine flow. In the hypothalamus, GluAP and AspAP increased, without significant changes in either AlaAP or CysAP. In contrast with effects in plasma, GluAP was unaffected, AspAP decreased, while AlaAP and CysAP increased. In the kidney, enzymatic activities did not change in the cortex, but decreased in the medulla. These data suggest that after ACE inhibition, the metabolism of Ang I in hypothalamus may lead mainly to Ang 2-10 formation. In plasma, the results suggest an increased formation of Ang IV together with increased vasopressinase activity. In the kidney, there is a reduction of vasopressinase activity in the medulla, suggesting a functional reduction of vasopressin in this location. The present data suggest the existence of alternative pathways in addition to ACE inhibition that might be involved in reducing BP after captopril treatment.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Captopril/farmacologia , Cistinil Aminopeptidase/metabolismo , Endopeptidases/metabolismo , Hipertensão/tratamento farmacológico , Hipertensão/enzimologia , Hipotálamo/enzimologia , Angiotensina II/antagonistas & inibidores , Angiotensina II/sangue , Angiotensina II/metabolismo , Animais , Cistinil Aminopeptidase/sangue , Ingestão de Líquidos/fisiologia , Endopeptidases/sangue , Hipertensão/urina , Hipotálamo/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/enzimologia , Masculino , Ratos , Ratos Wistar
5.
Scand J Gastroenterol ; 40(10): 1214-21, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16265778

RESUMO

OBJECTIVE: Catabolism and growth impairment are well-known complications of inflammatory bowel disease (IBD). This may be caused by the disease activity itself and/or the medical treatment, and both may lead to changes in the growth hormone (GH)/insulin-like growth factor I (IGF-I) axis. The aim of the present study was to examine the effects of enteral nutrition, Impact Powder, as adjuvant therapy to corticosteroid treatment on changes in the GH/IGF-I axis in patients with Crohn's disease (CD). MATERIAL AND METHODS: The patients were randomized to 3-IP (omega-3-fatty acid (FA), 3 g/day) or 6-IP (omega-6-FA, 9 g/day). Changes in total IGF-I (tIGF-I) and total IGF-II (tIGF-II), free IGF-I (fIGF-I), IGF binding proteins (IGFBP-1 and IGFBP-3), IGFBP-3 protease activity and insulin levels were examined in 31 patients with active CD (CDAI: 186-603) during treatment with prednisolone (40 mg for 1 week) and tapering the dose by 5 mg/week. Clinical and biochemical markers of inflammation were studied at day 0, and after 5 and 9 weeks. RESULTS: There were no differences at baseline between the two groups. During the treatment period, tIGF-I, fIGF-I and IGFBP-3 increased significantly in both groups compared to baseline (p<0.05) without differences between the groups. Insulin and IGFBP-1 showed no significant changes throughout the treatment period. CONCLUSIONS: There was no difference between 3-IP and 6-IP as adjuvant enteral nutrition on the GH/IGF-I axis. The changes observed in the GH/IGF-I axis are in line with previously published studies and may be explained by corticosteroid treatment; however, we cannot exclude an additional effect of omega3-/omega6 FA as adjuvant enteral nutrition.


Assuntos
Corticosteroides/uso terapêutico , Doença de Crohn/tratamento farmacológico , Ácidos Graxos Ômega-3/uso terapêutico , Ácidos Graxos Ômega-6/uso terapêutico , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/efeitos dos fármacos , Somatomedinas/efeitos dos fármacos , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Índice de Massa Corporal , Proteína C-Reativa/metabolismo , Doença de Crohn/sangue , Endopeptidases/sangue , Endopeptidases/efeitos dos fármacos , Feminino , Humanos , Imunoensaio , Insulina/sangue , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/sangue , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/classificação , Masculino , Pessoa de Meia-Idade , Prednisolona/uso terapêutico , Somatomedinas/classificação , Somatomedinas/metabolismo , Resultado do Tratamento
6.
J Extra Corpor Technol ; 33(2): 117-25, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11467439

RESUMO

Heparin-induced thrombocytopenia (HIT) is described as an allergy-like adverse reaction to heparin. It is a potentially severe complication of heparin therapy that can result in serious or life-threatening venous or arterial thromboembolic events. In the United States, lepirudin (Aventis Pharma AG, Strasbourg, France) is an approved therapy for anticoagulation in patients with HIT requiring anticoagulation. Lepirudin is a recombinant form of hirudin, a leech enzyme that is a highly specific direct inhibitor of thrombin. Lepirudin monitoring during surgery can be managed with ecarin clotting time (ECT) (Cardiovascular Diagnostics, Inc., Raleigh, NC), which has recently been approved as a humanitarian device exemption (HDE) for use in the United States in the management of HIT with cardiopulmonary bypass. This case report describes a patient with HIT who was managed successfully with lepirudin and ECT during coronary artery bypass grafting.


Assuntos
Anticoagulantes/uso terapêutico , Testes de Coagulação Sanguínea , Ponte Cardiopulmonar , Endopeptidases/sangue , Heparina/efeitos adversos , Terapia com Hirudina , Proteínas Recombinantes/uso terapêutico , Trombocitopenia/induzido quimicamente , Anticoagulantes/efeitos adversos , Hirudinas/análogos & derivados , Humanos , Masculino , Pessoa de Meia-Idade , Pennsylvania
7.
Rocz Akad Med Bialymst ; 46: 240-50, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11780568

RESUMO

Ethanol oxidation in the liver is accompanied by formation of acetaldehyde and free radicals. These compounds can react with biologically active proteins, including proteolytic enzymes and their inhibitors. The aim of this paper was to determine the influence of green tea on the activity of cathepsin G and elastase and their inhibitors such as alpha-1-antitrypsin and alpha-2-macroglobulin, total antioxidant status and lipid peroxidation in plasma of young rats chronically intoxication with ethanol. The activity of cathepsin G and elastase was increased, while the activity of their inhibitors was reduced after ethanol treatment. AT the same time, the total antioxidant status was significantly decreased while lipid peroxidation measured as malondialdehyde and 4-hydroxynonenal was significantly increased. Giving green tea to rats did not change the proteases and their inhibitors activity, but significantly increased total antioxidant status and decreased lipid peroxidation. Drinking green tea with ethanol partially prevents the changes observed after ethanol intoxication.


Assuntos
Alcoolismo/sangue , Endopeptidases/sangue , Inibidores de Proteases/sangue , Chá , Alcoolismo/enzimologia , Animais , Antioxidantes/metabolismo , Peroxidação de Lipídeos , Masculino , Ratos , Ratos Wistar
8.
Artigo em Russo | MEDLINE | ID: mdl-10429563

RESUMO

Experiments on 36 male rats with experimental hyperlipoproteinemia demonstrated that transcerebral exposure to impulse current (100 Hz, 2mA) aggravates atherogenic alterations, provokes hyperactivation of kallikrein-kinin system and unbalance of elastase inhibitory activity in the serum and myocardium. The latter may contribute to better vascular permeability for low-density lipoproteins, to development of edema of vascular intima, lability of cellular and lysosomal membranes with hydrolysis of elastine and collagen fibers of myocardial vessels and other organs. Transcerebral exposure to electromagnetic UHF field (40.68 MHz) is not hypolipidemic but has no negative effect on experimental atherosclerosis, promotes normalization of kallikrein-kinin system in the serum, activation of this system in the myocardium and cerebral cortex, correction of destructive processes in the serum and cerebral cortex with a risk of their development in the myocardium.


Assuntos
Eletricidade/efeitos adversos , Campos Eletromagnéticos/efeitos adversos , Endopeptidases/sangue , Hiperlipoproteinemias/enzimologia , Inibidores de Proteases/sangue , Animais , Encéfalo/fisiologia , Terapia por Estimulação Elétrica , Hiperlipoproteinemias/terapia , Sistema Calicreína-Cinina/fisiologia , Masculino , Ratos
9.
Blood ; 90(3): 1300-8, 1997 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9242565

RESUMO

Two major causes of the anemia in beta-thalassemia are a deficiency in hemoglobin (Hb) beta-subunit (and consequently HbA) synthesis and, due to the resulting excess of Hb alpha-subunits, erythroid cell hemolysis. The hemolytic component might be ameliorated by increasing the intracellular proteolysis of the excess alpha-subunits. Isolated 3H-labeled alpha-chains are known to be degraded primarily by the adenosine triphosphate (ATP)- and ubiquitin (Ub)-dependent proteolysis pathway in unfractionated beta-thalassemic hemolysates. Our objective was to increase this degradation by targeted intervention. Ub aldehyde (Ubal), a synthetic inhibitor of isopeptidases (proteases that hydrolyze the bond between the Ub polypeptide and its protein adduct), was added to reaction mixtures containing a hemolysate from the blood cells of one of four beta-thalassemic donors and 3H-alpha-chains or 3H-alpha-globin as a substrate. Optimum enhancement of ATP-dependent degradation occurred at 0.4 to 1.5 micromol/L Ubal and ranged from 29% to 115% for 3H-alpha-chains and 47% to 96% for 3H-alpha-globin among the four hemolysates. We suggest that Ubal stimulates 3H-alpha-subunit proteolysis by inhibition of an isopeptidase(s) that deubiquitinates, or "edits," Ub-3H-alpha-subunit conjugates, intermediates in the degradative pathway. In control studies, similarly low Ubal concentrations did not enhance the degradation of 3H-alpha2beta2 (HbA) tetramers or inhibit the activities of methemoglobin reductase and four selected glycolysis pathway enzymes. These and other results may be the basis for a therapeutic approach to beta-thalassemia.


Assuntos
Trifosfato de Adenosina/fisiologia , Carbono-Nitrogênio Liases , Endopeptidases/sangue , Globinas/metabolismo , Hemoglobina A/metabolismo , Ubiquitinas/análogos & derivados , Talassemia beta/sangue , Sistema Livre de Células , Avaliação Pré-Clínica de Medicamentos , Hemólise , Humanos , Liases/antagonistas & inibidores , Liases/sangue , Estimulação Química , Ubiquitinas/farmacologia , Talassemia beta/genética
10.
Acta Anaesthesiol Scand ; 35(1): 71-6, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2006603

RESUMO

Fourteen patients undergoing open-heart surgery received intermittent or continuous postoperative autotransfusion of shed mediastinal blood (minimum 400 ml during 6 h after surgery) collected in the cardiotomy reservoir. Hematologic variables and changes in the coagulation, fibrinolytic and plasma kallikrein-kinin systems were investigated in the reservoir blood at the beginning and after 6 h of autotransfusion, and in patient blood during and after surgery and before and after autotransfusion. Autotransfusion volume ranged from 400 to 1200 ml per patient (median 482 ml). The reservoir blood had a median haemoglobin level of 93 and 74 g/l, a platelet count of 71 and 119 x 10(9)/l, and plasma haemoglobin level of 3110 and 4100 mg/l before and after 6 h of autotransfusion, respectively. Further examination of the reservoir blood showed that it had undergone extensive coagulation and fibrinolysis as well as a moderate activation of the kallikrein-kinin system. Despite these extensive alterations in the reservoir blood, no major change could be found in the circulating blood after autotransfusion, except for a moderate increase in plasma haemoglobin from 180 mg/l to 430 mg/l. The clinical safety and simplicity of this technique were confirmed for autotransfusion of shed mediastinal blood up to 1200 ml.


Assuntos
Transfusão de Sangue Autóloga , Sangue , Procedimentos Cirúrgicos Cardíacos , Endopeptidases/sangue , Mediastino , Idoso , Humanos , Pessoa de Meia-Idade , Período Pós-Operatório
11.
Anesteziol Reanimatol ; (5): 6-9, 1989.
Artigo em Russo | MEDLINE | ID: mdl-2688481

RESUMO

The use of a "Cell-Saver" technique prevented hyperproteolysis and deletion of proteinase inhibitors in the blood plasma of patients during cardiopulmonary bypass. The technique also improved the course of the postoperative period, decreased the incidence of lung complications and prevented effectively postoperative bleedings. A prognostic value of alpha 1-proteinase inhibitor to trypsin activity ratio in the blood plasma of patients subject of cardiopulmonary bypass surgery has been demonstrated.


Assuntos
Endopeptidases/sangue , Circulação Extracorpórea/métodos , Transfusão de Sangue Autóloga , Separação Celular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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