An inhibitory monoclonal antibody to factor X that blocks prothrombin activation but not prothrombinase enzyme assembly

A monoclonal antibody (designated alpha BFX-2b) prepared against bovine factor X inhibited factor X activity in human, bovine, porcine, rabbit, and canine plasma. In assays using purified prothrombinase components, factor Xa, factor Va, phospholipid vesicles, and calcium ion with the fluorescent active site thrombin inhibitor dansylarginyl-N-(3-ethyl-1,5- pentanediyl)amide, the antibody inhibited the conversion of prothrombin to thrombin. Antibody alpha BFX-2b also blocked prothrombinase cleavage of the macromolecular substrates prethrombin 1 and prethrombin 2 but did not inhibit factor Xa hydrolysis of the synthetic substrate benzoyl- Ile-Glu-Gly-Arg-p-nitroanilide. The antibody also prevented the inactivation of factor Xa by antithrombin III but did not prevent the inactivation by soybean trypsin inhibitor. Antibody alpha BFX-2b bound factor Xa with a stoichiometry of 1:1 and an apparent dissociation constant of 9.0 x 10(-11) mol/L as estimated from its inhibition of prothrombinase activity. Antibody alpha BFX-2b did not prevent binding of factor Xa to factor Va-phospholipid as measured by using fluorescence polarization or high-pressure liquid gel chromatography with the fluorescent Factor Xa analogue dansyl-glutamyl-glycyl-arginyl- Xa. Immunoblotting of factor X following electrophoresis on sodium dodecyl sulphate-polyacrylamide gels and transfer to nitrocellulose indicated that the antigenic determinant recognized by antibody alpha BFX-2b was found on the heavy chain of factors X and Xa. From these observations it can be concluded that antibody alpha BFX-2b recognizes a highly conserved epitope on the factor X heavy chain that is remote from the topographic sites required for prothrombinase complex assembly and substrate hydrolysis but may be located at or near a portion of the macromolecular substrate binding site.     

Cystic fibrosis: An update for clinicians. Part 2: Hepatobiliary and pancreatic manifestations

This paper, the second in the series, will build on the first and explore the importance of liver and pancreatic manifestations of cystic fibrosis (CF) and the effect on morbidity and mortality of this multifaceted genetic condition. It will also further develop the critical role of the gastroenterologist as part of the multidisciplinary group of clinicians and allied health staff in the effective management of patients with CF.     

头皮糠疹与巯氧吡啶锌

头皮糠疹是常见病是多发病,临床表现为头皮红斑和脱屑,提示皮损部位表皮结构和功能异常,头皮角质层代谢紊乱,最近对头皮糠疹病因和病理的研究证实马拉色菌,皮脂分泌和个体敏感性是形成上述皮损的3个关键因素,硫氧吡啶锌（PTZ或ZPT）可以有效地杀灭马拉色菌,PTZ的颗粒大小和形状对其在头皮的生物利用度有明显的影响。此外,PTZ的抗菌效果有赖于其分子结构的完整性,在外用制剂中加入附加的游离锌,可以有效防止PTZ解离,从而提高其疗效。     

Effectiveness of stimulated menstrual cycles and Percoll sperm preparation in intrauterine insemination

To examine the usefulness of intrauterine insemination in women with various fertility factors, we retrospectively analyzed data from women treated during 1986 and 1987. Ninety-three patients underwent 1-11 cycles of single or double procedures, for a total of 423 inseminations in 263 treatment cycles. Twenty-six patients (28%) conceived, for a 10% total pregnancy rate per cycle, with 58% of the pregnancies resulting from double inseminations per cycle. An average of two treatment cycles was required to achieve pregnancy. Eight pregnancies (31%) occurred in spontaneous cycles, while 18 (69%) occurred in stimulated cycles. While clomiphene citrate therapy was useful in anovulatory patients, it was of no benefit in ovulatory patients being treated with intrauterine insemination. Human menopausal gonadotropin therapy was of benefit in both ovulatory and anovulatory patients when combined with intrauterine insemination. The live birth rate was higher (75%) in spontaneous cycles than in stimulated cycles (44%). Semen preparation was accomplished by sperm washing in 61% of the pregnancies and by Percoll preparation in 39%. The effectiveness of the discontinuous Percoll gradient for semen preparation for insemination was suggested by a pregnancy rate of 9% per cycle. While the mean sperm count in the pregnant group was 44 million, successful pregnancy was accomplished with a double insemination of 880,000 and 1.16 million rapidly progressive sperm in the first and second inseminate, respectively. The data confirm the important role of intrauterine insemination for the treatment of infertility.     

Predictive value of sperm hyperactivation measurements based on the dilution effect method in clinical in vitro fertilization.

Sperm hyperactivation motility characterized by wide oscillatory movements of the sperm head, nonlinear directions, and rapid motility with occasional star-shaped pattern of movement was measured during routine semen analyses prior to an in vitro fertilization procedure. The method consisted of diluting liquefied semen 1:20 with Ham's F-10 supplemented with processed human cord sera followed by incubation at 37 degrees C for 30 minutes. At the end of the incubation period, aliquots of semen samples were evaluated by phase contrast microscopy for sperm hyperactivation. The results indicated that (1) sperm samples exhibiting 15% or more hyperactive motility were associated with a significantly higher percent fertilization of oocytes during the IVF procedure; (2) sperm hyperactive motility was correlated to sperm fertilizability during IVF treatment cycles.     

Correlation of postcoital evaluation with in vitro sperm cervical mucus determinations and ureaplasma cultures

Fifteen trials were completed in 14 couples during an infertility evaluation. The postcoital test (PCT) was accomplished in a standardized manner. Also, standardized determinations of the sperm-cervical mucus penetration test (SCMPT) with the addition of cross-testing (X-test) utilizing bovine cervical mucus (BCM) and normal donor semen (NDS) were done. Male and female samples were also cultured for Ureaplasma urealyticum using U9-B indicator broth and A-7 agar. The PCT and SCMPT agreed in 87% (13/15) of the cases. Utilizing BCM and NDS, where possible, the causative factor was the cervical mucus in 54% (7/13); semen factor in 15% (2/13); both factors in 8% (1/13); and undetermined in 23% (3/13). U. urealyticum cultures were positive in 40% (6/15) of the cases. Analysis of the results revealed: (1) significant correlation between PCT and SCMPT (P less than 0.01); (2) no significant difference among the PCT, SCMPT, and X-test, indicating that the cervical mucus was the causative factor; and (3) no U. urealyticum correlation with the PCT or the SCMPT. Thus, laboratory SCMPT and X-test correlated with the PCT, providing additional information concerning the causative factor in infertility. The U. urealyticum status in cervical mucus and semen cannot be determined from the PCT nor the SCMPT.     

Loss of tumor-promoting activity of unleaded gasoline in N- nitrosodiethylamine-initiated ovariectomized B6C3F1 mouse liver

Unleaded gasoline (UG) vapor (2056 ppm) increased the incidence of liver tumors in a chronic bioassay and exhibited tumor-promoting activity in N-nitrosodiethylamine (DEN)-initiated female mouse liver. Estrogen inhibited mouse liver tumor development and the hepatocarcinogenic and tumor-promoting dose of UG produced uterine changes suggestive of estrogen antagonism. To directly test the hypothesis that UG-induced tumor-promoting ability is secondary to its interaction with the mouse liver tumor inhibitor, estrogen, we compared the tumor-promoting ability of UG in ovariectomized (Ovex) mice with the hepatic tumor-promoting ability of UG in intact mice. Ovaries were surgically removed at 4 weeks of age. Exposure to wholly vaporized UG (2018 ppm) under bioassay and tumor-promoting conditions began at 8 weeks of age. After 4 months of exposure, UG increased relative liver weight and hepatic microsomal cytochrome P450 pentoxyresourfin-O- dealkylase and ethoxyresorufin-O-deethylase activity to a similar extent in intact and Ovex mice. Non-focal hepatocyte proliferation, as measured by the incorporation of bromo-deoxyuridine, was not changed by UG exposure and was similar in all treatment groups. After 4 months of exposure to DEN-initiated mice, UG significantly increased the volume fraction of liver occupied by foci (three-fold) as compared to control intact mice. As expected, volume of foci was elevated in DEN/Ovex/control mice as compared to DEN/intact/control mice. In DEN/Ovex mice UG did not significantly increase the focal volume fraction. Thus, the tumor promoting activity of UG, as demonstrated by increased volume fraction of liver occupied by hepatic foci in intact mice, is greatly attenuated in Ovex mice. The volume fraction data in Ovex mice support the hypothesis that the tumor promoting activity of UG is dependent upon the interaction of UG with ovarian hormones. These data also indicate that hepatic microsomal cytochrome P450 PROD and EROD induction, hepatomegaly and non-focal hepatic LI are not specific markers of hepatic tumor promoting activity of UG.