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71.
CF Dalton SM Laird SE Estdale HG Saravelos TC Li 《Canadian Metallurgical Quarterly》1998,13(11):3197-3202
The concentrations of endometrial proteins PP14 and CA-125 were measured in uterine flushings taken on days LH+10 and LH+12 (10 and 12 days after luteinizing hormone surge) of the menstrual cycle from 15 normal, fertile women and 49 women who suffered recurrent miscarriage. The concentration of PP14 was significantly lower in the flushings from the recurrent miscarriage patients than in those from fertile controls on both day LH+10 (median: 1300, range: 3-10 300 ng/ml versus median: 13 933, range: 2174-40 404 ng/ml; P < 0.01) and LH+12 (median: 1560, range: 820-12 100 ng/ml versus median: 14 047, range 1402-62 108 ng/ml; P < 0.05). Similarly concentrations of CA-125 were significantly lower in flushings from recurrent miscarriage women compared to controls on both day LH + 10 (median: 1555, range: 47-6710 U/ml versus median: 6385.5, range 2884-27 731 U/ml, P < 0.01) and LH+12 (median: 2892, range: 956-9974 U/ml versus median: 7127.5, range: 1591-21 343 U/ml; P < 0.05). In contrast there was no significant difference in the concentration of PP14 in plasma samples taken on the same days as the flushings from recurrent miscarriage patients and fertile controls. The concentrations of PP14 in uterine flushings obtained on day LH + 10 or LH + 12 from recurrent miscarriage women during a pre-pregnancy investigative cycle were significantly lower (P < 0.05) in patients who went on to miscarry (median: 1000, range: 9-2900 ng/ml) than those who went on to have a live birth (median: 1440, range: 4-12 100 ng/ml) during a subsequent pregnancy. In contrast there was no significant difference in uterine CA-125 or plasma PP14 concentrations between these two groups of recurrent miscarriage patients. The results suggest that measurements of uterine PP14 and CA-125 may be useful in the assessment of endometrial development in recurrent miscarriage patients and suggest the importance of PP14 in preparing the endometrium for embryo implantation. In addition pre-pregnancy uterine PP14 measurements may be useful in predicting subsequent pregnancy outcome. 相似文献
72.
M Müller M Brunner R Schmid RM Mader J Bockenheimer GG Steger B Steiner HG Eichler B Bl?chl-Daum 《Canadian Metallurgical Quarterly》1998,58(14):2982-2985
The transfer of cytotoxic agents across the tumor endothelium into the interstitial tumor space is considered a critical step in clinical resistance of solid tumors to antineoplastic chemotherapy. However, experimental data on drug transfer from the blood into the interstitium of solid tumors are scarce. Therefore, in this study, we used an innovative technique, in vivo microdialysis, for measuring interstitial tumor pharmacokinetics and plasma-to-tumor transfer rates of methotrexate (MTX) in breast cancer patients. Microdialysis probes were inserted into the primary tumor and the periumbilical s.c. adipose layer of nine previously chemotherapy-naive breast cancer patients to monitor interstitial concentrations following i.v. administration of MTX (40 mg/m2) during a three-drug treatment regimen. Mean interstitial MTX load in breast tumors, expressed as area under curve (AUC), was 60 +/- 20% (mean +/- SE; coefficient of variation = 100%) of mean plasma MTX load. There was no correlation between plasma AUC and the AUC in the interstitial space of tumor tissue (P = 0.93). Not one of the parameters plasma, interstitial tumor load, and transfer rate of MTX to the interstitial space was associated with favorable clinical response. In conclusion, plasma levels of MTX are not predictive of intratumor levels. There is a high interindividual variability in transendothelial MTX transfer. Under the present conditions, access of MTX to the interstitial space is not a rate-limiting step for clinical response to chemotherapy. 相似文献
73.
WK Wang T Dudek YJ Zhao HG Brumblay M Essex TH Lee 《Canadian Metallurgical Quarterly》1998,95(10):5740-5745
The seven-transmembrane CCR5 was recently found to double as a coreceptor for a genetically diverse family of human and nonhuman primate lentiviruses. Paradoxically, the main region of the envelope protein believed to be involved in CCR5 utilization was mapped to hypervariable region 3, or V3, of the envelope glycoprotein gp120. In this study, we addressed the question of whether functional convergence in CCR5 utilization is mediated by certain V3 residues that are highly conserved among HIV type 1 (HIV-1), HIV type 2, and simian immunodeficiency virus. Site-directed mutagenesis carried out on three such V3 residues revealed that the Arg-298 of HIV-1 gp120 has an important role in CCR5 utilization. In contrast, no effect was observed for the other residues we tested. The inability of Arg-298 mutants to use CCR5 was not attributed to global alteration of gp120 conformation. Neither the expression, processing, and incorporation of mutant envelope proteins into virions, nor CD4 binding were significantly affected by the mutations. This interpretation is further supported by the finding that alanine substitutions of five residues immediately adjacent to the arginine residue had no effect on CCR5 utilization. Taken together, our data strongly suggests that the highly conserved Arg-298 residue identified in the V3 of HIV-1 has a significant role in CCR5 utilization, and may represent an unusually conserved target for future anti-viral designs. 相似文献
74.
HG Goovaerts TJ Faes GW de Valk-de Roo M ten Bolscher JC Netelenbosch WJ van der Vijgh RM Heethaar 《Canadian Metallurgical Quarterly》1998,19(4):517-526
The intestinal polyamine transporters have not yet been identified. Our aim was to characterize specific polyamine binding sites in rabbit intestinal brush-border membranes (IBBM) as a starting step for identification of polyamine transporters. This was investigated at 4 degrees and at low membrane concentration. Saturation isotherms for [3H]putrescine (PUT) binding indicated a single population of sites (puT) with a dissociation equilibrium constant Kd of 3.8 microM and a density of sites Bmax of 58 pmol/mg of protein. [3H]spermidine (SPD) binding also involved only one class of sites (spD), albeit with a lower affinity (Kd = 106 microM) and higher abundance (Bmax = 1240 pmol/mg of protein) than puT. On the contrary, [14C]spermine (SPM) bound two classes of sites (spM1 and spM2) differing in their affinity (Kd = 2.5 and 31.4 microM) and abundance (Bmax = 467 and 1617 pmol/mg of protein, respectively). Membrane association of SPM at 4 degrees was much faster than that of SPD and PUT, both of which proceeded at a similar rate. In contrast to PUT and SPD dissociation, SPM dissociation at 23 degrees did not follow a first-order reaction. Specifically bound [3H]PUT, unlike [3H]SPD and [14C]SPM, dissociated at 23 degrees independently of the addition of nonradioactive polyamine. Methylglyoxal-bis-(guanylhydrazone) was an extremely potent inhibitor of PUT binding (Ki = 3.2 +/- 1.5 nM), but as with PUT and cadaverine (CAD), it did not alter [3H]SPD and [14C]SPM binding substantially. The intestinal brush-border membrane may contain at least three sites specific for polyamine binding and exhibiting different ligand selectivity. Site puT might be associated with the transport system already described for intestinal uptake of PUT. 相似文献
75.
The role of prostacyclin and thromboxane A2 in the pathogenesis of Bartter's syndrome was investigated by measurement of the urinary excretion of 6-keto-PGF1 alpha and thromboxane B2, respectively, in five patients. The prostaglandin metabolites were extracted from urine by a reproducible method and measured by specific radioimmunoassays. The patients with Bartter's syndrome excreted about four-times as much 6-keto-PGF1 alpha as the normal controls. In contrast, there was no significant difference in the urinary excretion of thromboxane B2 between the patients and the controls. In a second part of the study, three patients were treated with indomethacin (150 mg/day for four days), an inhibitor of prostaglandin synthesis. This regimen suppressed urinary excretion of 6-keto-PGF1 alpha by 43% and that of thromboxane B2 by 46%. It is suggested that the increase in prostacyclin production is responsible for both the hyperreninemia and and the other endocrine derangements as well as the hyporesponsiveness of blood pressure to intravenous infusion of vasopressors in patients with Bartter's syndrome. 相似文献
76.
Between 1960 and 1972, 305 patients with malignomas of the thyroid gland were surgically treated, irradiated (megavoltage therapy and/or iodine-131), and treated with thyroid hormone according to principles formerly stated. Differentiated adenocarcinomas (34.4% of all the patients) were observed more frequently in women and younger patients, whereas dedifferentiated carcinomas (33.8%) are found relatively more often in men and in an advanced age. Only in 12% of the cases the tumor was discovered in an early stage; thus, an early diagnosis is much too rare so far. In almost two thirds of the patients a spread of metastases occurred. Of these, 11% grew manifest later than five years following the therapy. Distant metastases from differentiated adenocarcinomas accumulated I-131 in sixty per cent, those from undifferentiated carcinomas still in twenty per cent. Treatment results are influenced decisively by histology, tumor spread, age and sex, women less than forty years old with differentiated adenocarcinomas and a circumscribed extension of the tumor having the best prognosis. More prognostic importance is due to the extension of the primary tumor than to the presence of metastases to regionary lymph nodes. Patients with metastases accumulating I-131 have a better chance of survival than those whose metastases do not accumulate. By means of standardized therapeutic rules, utilizing modern therapeutic techniques and based on interdepartmental cooperation, it was possible to improve the results partly by the two- or threefold as compared to a previously treated group of patients. 相似文献
77.
78.
Plaque samples were obtained from 13 children receiving long-term therapy with benzathine penicillin for the prevention of rheumatic fever recurrences, 31 children receiving oral sulfadiazine for the same purpose, and 29 untreated siblings. The therapies were found to have no effect upon the proportions of Streptococcus mutans or lactobacilli in dental plaque, upon the percentage of children harboring the organisms, nor upon the susceptibility of the organisms to penicillin and sulfadiazine. Of the S. mutans strains tested, 97% had a minimal inhibitory concentration of penicillin G of less than 48 ng/ml and, of the lactobacillus strains tested, 96.8% had a minimal inhibitory concentration of less than 1,600 ng/ml. All strains of both organisms were profoundly resistant to sulfadiazine. 相似文献
79.
80.