RÉSUMÉ
Patients presenting with a post-invasive procedure hematoma can be treated with medicinal leeches to evacuate the hematoma. Our patient, a postmenopausal woman in her 60s, with a past medical history of hypothyroidism, presented to the outpatient clinic with pain, redness, warmth, and swelling on her right thigh. Ten days prior, the patient had undergone a subcutaneous pellet implant procedure in the right thigh for hormonal replacement therapy. The patient developed post-procedure cellulitis and soft tissue infection and was treated with antibiotics. The patient developed a progressively enlarged hematoma at the implant site. The hematoma was treated with medicinal leeches. Two weeks after treatment, the implant area healed. The patient had a family history of von Willebrand disease and a history of prolonged bleeding during childbirth, menstruation, and dental procedures. A von Willebrand panel was obtained, and the results were consistent with a new diagnosis of von Willebrand disease.
RÉSUMÉ
Free radicals are closely related to the occurrence and development of aging, cancer and inflammation. In this paper, the microbial transglutaminase (MTGase) was used as a catalyst to graft the collagen peptide (COP) molecules on the amino group of carboxymethyl chitosan sulfate (CMCS) to improve the antioxidant effects. FT-IR and NMR spectroscopy were used to confirm the successful grafting of COP to CMCS. Degree of substitution (DS) of CMCS-COP could be controlled by adjusting the reaction conditions. With the increase of concentration, the ability of each sample on scavenging capacity and reducibility tends to increase obviously. The results of anticoagulant experiments showed that the ability of CMCS and CMCS-COP with three different degrees of substitution on activated partial thrombin time (APTT) and prothrombin time (PT) values were all increased to compare with the control group. No relevant cytotoxicity against NIH-3T3 mouse fibroblasts was found for the copolymers. These results suggested that CMCS-COP would appear to be a promising candidate for wound dressing application.
Sujet(s)
Chitosane/analogues et dérivés , Collagène/pharmacologie , Fragments peptidiques/pharmacologie , Transglutaminases/composition chimique , Animaux , Anticoagulants/synthèse chimique , Anticoagulants/composition chimique , Anticoagulants/pharmacologie , Anticoagulants/toxicité , Bandages , Chitosane/synthèse chimique , Chitosane/composition chimique , Chitosane/pharmacologie , Chitosane/toxicité , Collagène/synthèse chimique , Collagène/composition chimique , Collagène/toxicité , Piégeurs de radicaux libres/synthèse chimique , Piégeurs de radicaux libres/composition chimique , Piégeurs de radicaux libres/pharmacologie , Piégeurs de radicaux libres/toxicité , Souris , Structure moléculaire , Cellules NIH 3T3 , Oxydoréduction , Temps partiel de thromboplastine , Fragments peptidiques/synthèse chimique , Fragments peptidiques/composition chimique , Fragments peptidiques/toxicité , Temps de prothrombine , TempératureRÉSUMÉ
Sulfated glycosaminoglycans (SGNL) were extracted for the first time from Norway lobster (Nephrops norvegicus) shell. The monosaccharide composition analysed by GC/MS revealed the presence of galacturonic acid, glucuronic acid, N-acetylgalactosamine and N-acetylglucosamine. The analysis of SGNL with acetate cellulose electrophoresis in Zn-acetate revealed the presence of heparan sulfate (HS) and dermatan sulfate (DS). SGNL were evaluated for their anticoagulant activities using activated partial thromboplastin time (aPTT), thrombin time (TT) and prothrombine time (PT) tests. After 21h incubation, HCT116 cell proliferation was inhibited (p<0.05) between 39.7 and 54.8% at 1.5-7.5mg/mL of SGNL. SGNL don't show hemolytic activity towards bovine erythrocytes and no cytotoxicity against the normal lymphocytes. The antiproliferative efficacy of these lobster glycosaminoglycans were probably related with the higher sulfate content. SGNL demonstrated promising antiproliferative and anticoagulant potential, which may be used as a novel, effective and promising antithrombotic agent.
Sujet(s)
Coquilles d'animaux/composition chimique , Anticoagulants/pharmacologie , Côlon/anatomopathologie , Glycosaminoglycanes/isolement et purification , Glycosaminoglycanes/pharmacologie , Nephropidae/composition chimique , Animaux , Bovins , Mort cellulaire/effets des médicaments et des substances chimiques , Prolifération cellulaire/effets des médicaments et des substances chimiques , Électrophorèse , Cellules HCT116 , Hémolyse/effets des médicaments et des substances chimiques , Humains , Temps partiel de thromboplastine , Temps de prothrombine , Spectrophotométrie UV , Spectroscopie infrarouge à transformée de FourierRÉSUMÉ
The paper discusses the non-anticoagulant properties of unfractionated heparin and enoxaparin and their relation to their chemical structures. It is emphasized that enoxaparin has multiple, often interrelated, non-anticoagulant effects that can complement its antithrombotic activity and enhance the efficiency of therapy in patients receiving the drug for various indications. The realization of these effects requires the complex structure with the standard distribution of molecular weight (Mw) (average Mw, about 4500 Da, as well as Mw of less than 2000 Da (<20%), 2000 to 8000 Da (>68%), and more than 8000 Da (<18%), and with the standard content of 1.6-anhidro rings (15-25%), which is determined by the source of raw materials and by the production technology of the original drug and cannot be fully reproduced when designing its bioanalogues.
Sujet(s)
Anticoagulants/pharmacologie , Héparine bas poids moléculaire/pharmacologie , Énoxaparine/pharmacologie , HumainsRÉSUMÉ
Researches on blood purification membranes are fuelled by diverse clinical needs, such as hemodialysis, hemodiafiltration, hemofiltration, plasmapheresis, and plasma collection. To approach high-performance dialyzer, the integrated antifouling and antithrombotic properties are highly necessary for the design/modification of advanced artificial membranes. In this study, we propose and demonstrate that the physical blend of triblock polyurethane (PU) and polyethersulfone (PES) may advance the performance of hemodialysis membranes with greatly enhanced blood compatibility. It was found that the triblock PU could be blended with PES at high ratio owing to their excellent miscibility. The surfaces of the PES/PU composite membranes were characterized using attenuated total reflectance-Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, water contact angle measurement, and surface ζ-potentials. The results indicated that the membrane surfaces were assembled with hydrophilic segregation layer owing to the migration of amphiphilic PU segments during membrane preparation, which might confer the composite membranes with superior hemocompatibility. The cross-section scanning electron microscopy images of the composite membranes exhibited structure transformation from finger-like structure to sponge-like structure, which indicated that the composite membrane had tunable porosity and permeability. The further ultrafiltration experiments indicated that the composite membranes showed increased permeability and excellent antifouling ability. The blood compatibility observation indicated that PES/PU composite membranes owned decreased protein adsorption, suppressed platelet adhesion, and prolonged plasma recalcification time. These results indicated that the PES/PU composite membranes exhibited enhanced antifouling and antithrombotic properties than the pristine PES membrane. The strategy may forward the fabrication of blood compatible composite membranes for clinical blood dialysis by using the various functional miscible polymers.
Sujet(s)
Test de matériaux , Membrane artificielle , Polymères/composition chimique , Polyuréthanes/composition chimique , Dialyse rénale/méthodes , Sulfones/composition chimique , Humains , Porosité , Dialyse rénale/instrumentationRÉSUMÉ
Thrombin-binding aptamer (TBA) is a 15-nt DNA oligomer that efficiently inhibits thrombin. It has been shown that TBA folds into an anti-parallel unimolecular G-quadruplex. Its three-dimensional chair-like structure consists of two G-tetrads connected by TT and TGT loops. TBA undergoes fast degradation by nucleases in vivo. To improve the nuclease resistance of TBA, a number of modified analogs have been proposed. Here, we describe anomeric modifications of TBA. Non-natural α anomers were used to replace selected nucleotides in the loops and core. Significant stabilization of the quadruplex was observed for the anomeric modification of TT loops at T4 and T13. Replacement of the core guanines either prevents quadruplex assembly or induces rearrangement in G-tetrads. It was found that the anticoagulant properties of chimeric aptamers could be retained only with intact TT loops. On the contrary, modification of the TGT loop was shown to substantially increase nuclease resistance of the chimeric aptamer without a notable disturbance of its anticoagulant activity.