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1.
J Biomed Mater Res B Appl Biomater ; 102(6): 1207-16, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24425361

RESUMO

Various clinical procedures, such as cardiovascular surgery or extracorporeal blood purification, involve systemic anticoagulation using heparin. High concentrations of circulating heparin require neutralization due to possible serious bleeding complications. The intravenous administration of the heparin antagonist protamine sulfate is routinely clinically performed, but is frequently associated with adverse reactions. Therefore, there is a need for a valid and safe alternative to achieve extracorporeal heparin removal from blood or plasma, such as a filter, a matrix, or an adsorbent. Here, we describe the development of a macroporous poly(2-hydroxyethyl methacrylate)-based monolithic cryogel functionalized with l-lysine (pHEMA-lys) and the characterization of its selective heparin adsorption. The maximum binding capacity was quantified in vitro using aqueous and serum solutions under static and dynamic conditions, and fresh human plasma under static conditions. The pHEMA-lys bound 40,500 IU and 32,500 IU heparin/g cryogel at the equilibrium in aqueous solution and 50% serum, respectively. In human plasma spiked with 100 IU/mL of heparin, the binding was still highly efficient (4330 IU/g cryogel after 30 min, i.e., 87% of the initial concentration). The cryogels showed good blood compatibility, as indicated by negligible adsorption of albumin, antithrombin III, and total protein, and may thus be suitable for extracorporeal heparin removal.


Assuntos
Anticoagulantes/química , Criogéis/química , Heparina/química , Poli-Hidroxietil Metacrilato/química , Adsorção , Anticoagulantes/farmacocinética , Heparina/farmacocinética , Humanos , Desintoxicação por Sorção/métodos
2.
Org Lett ; 3(11): 1605-8, 2001 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-11405666

RESUMO

Treatment of 1,5-bridged calix[8]arenes 2-4 with alkali metal carbonates produces salts in which an included cation acts as a conformational template. This induces the folding of calix[8]arene skeleton in a conformation in which the triads of contiguous OH-bearing rings adopt a 3/4-cone conformation with all hydroxyls converging toward the same center. The template effect requires the presence of short bridges (ethylene, tetramethylene, diethylene glycol) and became stronger by increasing the cation dimension up to that of Cs(+).

3.
J Nat Prod ; 56(9): 1598-600, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8254353

RESUMO

Bioactivity-guided fractionation of the lipid extract of Crithmum maritimum using the brine shrimp lethality assay led to the isolation of three bioactive compounds. Two of these are known C17 polyacetylenic metabolites, falcarinol [1] and falcarindiol [2], previously isolated from several species of the Umbelliferae and Araliaceae. The third active principle was identified as O-geranylvanillin [3], an aromatic ether described in the literature as a synthetic compound but unknown as a natural product. Cytotoxic activity of the pure compounds was significant for 1 and 2, much less intense for 3.


Assuntos
Plantas Medicinais/química , Alcinos , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/toxicidade , Artemia , Benzaldeídos/química , Benzaldeídos/isolamento & purificação , Benzaldeídos/toxicidade , Di-Inos , Álcoois Graxos/química , Álcoois Graxos/isolamento & purificação , Álcoois Graxos/toxicidade , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Sicília , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
6.
Acta Haematol ; 76(1): 33-6, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-2878557

RESUMO

Ornithine decarboxylase (L-ornithine carboxylase, EC 4.1.1.17) and transglutaminase (R-glutaminylpeptide: amine gamma-glutamyltransferase, EC 2.3.2.13), enzymes implicated in the regulation of growth processes, were studied in lymphocytes from untreated patients with chronic lymphocytic leukemia. A marked increase of ornithine decarboxylase activity was found in lymphocytes from chronic lymphocytic leukemia patients when compared to normal human lymphocytes; in contrast, no transglutaminase activity was found in lymphocytes from untreated patients with chronic lymphocytic leukemia.


Assuntos
Leucemia Linfoide/enzimologia , Linfócitos/enzimologia , Proteínas de Neoplasias/análise , Ornitina Descarboxilase/análise , Transglutaminases/análise , Diferenciação Celular , Humanos , Transglutaminases/deficiência
7.
Acta Haematol ; 72(6): 361-7, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6442519

RESUMO

Peripheral blood T-lymphocyte subsets, evaluated by means of a series of monoclonal antibodies, were assessed in 14 patients affected by thalassaemia intermedia, 7 of them previously splenectomized. A significant reduction of T+4 cells ('helper' T cells) was found in almost all patients, whereas T+8 cells ('suppressor/cytotoxic') showed a marked increase only in splenectomized subjects. Together with these quantitative T-subset abnormalities, which seemed to be partly affected by either splenectomy or high serum iron levels, an unusual circulating T-cell subpopulation labelled by T6 monoclonal antibody was detected in all patients. Complete disappearance of T+6 cells ('thymocyte-like' T lymphocytes) and normalization of the T4/T8 ratio was observed after 'in vitro' incubation of patient's lymphocytes with a crude thymus extract (Thymostimulin). This would suggest the presence of a so far unreported thymus-dependent defect of T-lymphocyte phenotypic maturation occurring in thalassaemia intermedia.


Assuntos
Linfócitos T/classificação , Talassemia/imunologia , Timo/fisiopatologia , Adolescente , Adulto , Anticorpos Monoclonais , Criança , Feminino , Ferritinas/sangue , Humanos , Ferro/sangue , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Formação de Roseta , Esplenectomia , Talassemia/sangue , Extratos do Timo
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