High-performance liquid chromatographic method for the simultaneous determination of propafenone and 5-hydroxypropafenone in human serum.

A simple, rapid and sensitive high-performance liquid chromatographic method for the simultaneous determination of propafenone and 5-hydroxypropafenone in human serum is described. Method involves a single-step extraction of the drug and its metabolite with dichloromethane:2-propanol (4:1 v/v) mixture from 0.2 ml of serum. Separation of the investigated compounds on deactivated Supelcosil LC18-DB column is accomplished by ultraviolet detection at 210 nm. The limit of detection is 10 ng/ml for propafenone and 4 ng/ml for 5-hydroxypropafenone. The method is useful for the routine monitoring of propafenone and its main metabolite in serum as well as for the pharmacokinetic studies.     

Granulocyte colony stimulating factor treatment of resistant thin endometrium in women with frozen-thawed blastocyst transfer

The aim of the study was to assess the granulocyte-colony stimulating factor (G-CSF) effect on unresponsive thin (<7 mm) endometrium in women undergoing frozen-thawed embryo transfer at the blastocyst stage. A total of 62 women with thin unresponsive endometrium were included in the study, of which, 29 received a G-CSF infusion and 33 who opted out of the study served as controls. Patients in both groups had similar endometrial thickness at the time of the initial evaluation: 6.50 mm (5.50-6.80) in the G-CSF and 6.40 mm (5.50-7.0) in the control group. However, after the infusion endometrial thickness increased significantly in the G-CSF group in comparison with the controls (p=0.01), (Δ) 0.5 (0.02-1.2) (p=0.005). In the G-CSF group endometrium expanded to 7.90 mm (6.58-8.70) while in the control group to 6.90 mm (6.0-7.75). Five women in each group conceived. The clinical pregnancy rate was 5/29 (17.24%) in the G-CSF treated group and 5/33 (15.15%) in the control group (p>0.05). The live birth rate was 2/29 (6.89%) in the G-CSF group and 2/33 (6.06%) in the control group (p>0.05). We concluded that G-CSF infusion leads to an improvement in endometrium thickness but not to any improvement in the clinical pregnancy and live birth rates. Until more data is available G-CSF treatment should be considered to be of limited value in increasing pregnancy rate. Abbreviations: G-CSF: granulocyte colony-stimulating factor; M-CSF: macrophagecolony-stimulating factor; GM-CSF: granulocyte-macrophage colony-stimulating factor; FET: frozen embryo transfer; IVF: in vitro fertilization     

A novel 196Leu to Pro substitution in the beta3 subunit of the alphaIIbbeta3 integrin in a patient with a variant form of Glanzmann thrombasthenia

Glanzmann thrombasthenia (GT) is an inherited disorder where an absence of platelet aggregation is associated with quantitative or qualitative abnormalities of the alphaIIbbeta3 integrin. In rare patients, amino acid substitutions have provided information on the functional significance of specific domains within alphaIIb or beta3. We now report an elderly male GT patient (R.M.) from the south west of France whose platelets possess a small residual expression of alphaIIbbeta3. Furthermore, the integrin failed to undergo the necessary conformational changes following platelet activation to permit the binding of fibrinogen or activation-dependent monoclonal antibodies despite the presence of an RGD-binding site. Screening of the alphaIIb and beta3 genes by PCR-SSCP revealed a heterozygous mutation at position 685 in exon 5 of the beta3 gene leading to a 196Leu to Pro substitution. 196Leu is a highly conserved amino acid of beta3. The other beta3 allele appeared to be silent. This mutation, inherited from his mother and present in other family members with intermediate levels of alphaIIbbeta3, was close to the MIDAS-like domain of beta3, a fact that appears to explain its effect on alphaIIbbeta3 activation and fibrinogen binding.     

A human monoclonal autoantibody recognizes a neoantigen on glycoprotein IIIa expressed on stored and activated platelets

We prepared a heterohybrid cell line that secretes a human IgM monoclonal autoantibody that recognizes an antigen found on thrombin-activated or stored platelets. The surface expression of the epitope recognized by this autoantibody, 5E5, increases with time as platelets age in vitro, suggesting that it may represent a senescence or activation-specific antigen. 5E5 binds to the purified platelet membrane glycoprotein (GP) IIb-IIIa complex in an enzyme-linked immunosorbent assay (ELISA). In an immunoblot technique, 5E5 binds to a protein with an apparent mol wt of 95,000, which is identical to that of GPIIIa under nonreduced conditions. In crossed immunoelectrophoresis (CIE), the predominant antigen recognized by 5E5 is contained in the GPIIb-IIIa precipitin arc. An additional precipitin arc recognized by 5E5 is often observed only on gels derived from lysates of platelets stored under blood bank conditions for greater than 3 days. These findings illustrate the usefulness of human monoclonal antibodies for the identification of membrane neoantigens expressed as a result of platelet activation or revealed as platelets age in vitro.     

Identification of glycoprotein Ib as a target for autoantibody in idiopathic (autoimmune) thrombocytopenic purpura

An antibody (DIL) from a patient with idiopathic thrombocytopenic purpura (ITP) was shown to have autospecificity on the basis of reactions with autologous platelets that were identical to those obtained with platelets from normal subjects. DIL antibody also reacted strongly in an immunofluorescence test with platelets from a patient with Glanzmann's thrombasthenia, but failed to react with platelets from a patient with the Bernard-Soulier syndrome who was known to be deficient in glycoprotein Ib (GPIb). Purified GPIb and control platelets, but not Bernard-Soulier platelets, inhibited the lytic activity of DIL. Using the GPIb-specific monoclonal antibody AP1 and one-dimensional rocket electrophoresis into gels containing rabbit antihuman platelet membrane antibody, it was shown that staphylococcal protein A-Sepharose beads coated with DIL antibody selectively remove GPIb from solubilized platelet preparations. By crossed immunoelectrophoresis it was found that DIL recognizes a determinant on GPIb on the membrane side of the cleavage site of the platelet calcium- activated protease (calpain). These studies provide direct evidence for binding of a platelet autoantibody to a determinant on GPIb relatively close to the site of insertion of this protein into the platelet membrane.     

Effects of herbal preparation Equiguard on hormone-responsive and hormone-refractory prostate carcinoma cells: mechanistic studies

The Equiguard is a dietary supplement comprised of standardized extracts from nine herbs, respectively, Herba epimedium brevicornum Maxim (stem and leaves), Radix morindae officinalis (root), Fructus rosa laevigatae michx (fruit), Rubus chingii Hu (fruit), Schisandra chinensis (Turz.) Baill (fruit), Ligustrum lucidum Ait (fruit), Cuscuta chinensis Lam (seed), Psoralea corylifolia L. (fruit), and Astragalus membranaceus (Fisch.) Bge (root). This proprietary product, formulated according to Chinese traditional medicinal concepts, is aimed at restoring harmony in the of the kidney, an organ which Chinese medicinal principles consider to be vital for invigorating as well as maintaining balance of the entire urological system. As the prostate is an integral component of the urological system, we performed in vitro studies to test the effects of ethanol extracts of Equiguard to modulate prostate growth and gene expression. These studies used prostate cancer cells mimicking the androgen-dependent (AD) and androgen-independent (AI) states of prostate carcinogenesis. Results show that Equiguard significantly reduced cancer cell growth, induced apoptosis, suppressed expression of the androgen receptor (AR) and lowered intracellular and secreted prostate specific antigen (PSA), and almost completely abolished colony forming abilities of prostate cancer cells. These data support the interpretation that this herbal formulation contains ingredients that collectively may be efficacious in preventing or treating AD and AI prostate carcinoma. The anti-prostatic activities of Equiguard may stem from its complex composition capable of targeting multiple signal transduction/metabolic pathways, to effectively correct, counteract or circumvent the impaired or dysfunctional mechanisms accompanying different stages of prostate carcinogenesis.