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JC Royer DL Moyer SG Reiwitch MS Madden EB Jensen SH Brown CC Yonker JA Johnston EJ Golightly WT Yoder 《Canadian Metallurgical Quarterly》1995,13(13):1479-1483
We describe a novel fungal expression system which utilizes the Quorn myco-protein fungus Fusarium graminearum A 3/5. A transformation system was developed for F. graminearum and was used to introduce the coding and regulatory regions of a trypsin gene from Fusarium oxysporum. The protein was efficiently expressed, processed and secreted by the recombinant host strain. In addition, the promoter and terminator of the F. oxysporum trypsin gene have been successfully utilized to drive the expression of a cellulase gene from Scytalidium thermophilum and a lipase gene from Thermomyces lanuginosus in F. graminearum. 相似文献
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EB Rubenstein RJ Gralla JD Hainsworth PJ Hesketh TH Grote MR Modiano A Khojasteh LA Kalman CR Benedict WF Hahne 《Canadian Metallurgical Quarterly》1997,79(6):1216-1224
BACKGROUND: This double blind parallel group study assessed the acute antiemetic efficacy of four oral doses of dolasetron mesylate in cancer patients receiving their first course of intravenous chemotherapy with doxorubicin and/or cyclophosphamide. METHODS: Patients were randomized to receive 25, 50, 100, or 200 mg of dolasetron mesylate 30 minutes prior to chemotherapy and were monitored for nausea and emetic episodes for the next 24 hours. RESULTS: Three hundred and nineteen cancer patients at 32 sites completed the study. Most patients were female (81%); of this group, 69% had breast carcinoma. A highly statistically significant linear trend demonstrating improved response with higher doses was detected for complete response (no emetic episodes and no rescue medication) (P < 0.001), for complete plus major response (0-2 emetic episodes and no rescue medication) (P < 0.001), and for patient visual analog scale assessments of nausea (P = 0.001) and general satisfaction with antiemetic therapy (P = 0.001). No serious adverse events were noted. The most frequent adverse event was mild, self-limiting headache, which has been reported with other drugs in this class. CONCLUSIONS: Single oral doses of dolasetron mesylate were found to be effective in preventing acute emesis in cancer patients receiving moderately emetogenic chemotherapy. 相似文献
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Evidence for a third component in neutrophil aggregation: potential roles of O-linked glycoproteins as L-selectin counter-structures 总被引:2,自引:0,他引:2
TA Bennett CM Schammel EB Lynam DA Guyer A Mellors B Edwards S Rogelj LA Sklar 《Canadian Metallurgical Quarterly》1995,58(5):510-518
The homotypic aggregation of neutrophils requires the participation of L-selectin and the beta 2-integrins, but it has not been clear whether the two receptors recognize one another as counter-structures or whether other adhesion molecules are involved. We have examined aggregation of live neutrophils with target populations, manipulated to alter expression of adhesive epitopes, using flow cytometry. A target population depleted of both L-selectin and activatable beta 2-integrin displayed an ability to aggregate with live neutrophils, suggesting that these two molecules are not counter-structures. We also found that an O-sialoglycoprotease (GCP) from Pasteurella haemolytica is capable of inhibiting homotypic aggregation. Neutrophils treated with GCP lose O-glycosylated proteins but retain L-selectin and activatable beta 2-integrin. One or more of the GCP substrates appears to function in L-selectin-dependent binding but not in beta 2-integrin-dependent binding. Together the data suggest a mechanism of aggregation that is analogous to leukocyte-endothelial cell adhesion in which a low-affinity carbohydrate-dependent interaction precedes a high-affinity integrin-dependent adhesion. 相似文献
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EB Mechetner B Schott BS Morse WD Stein T Druley KA Davis T Tsuruo IB Roninson 《Canadian Metallurgical Quarterly》1997,94(24):12908-12913
The MDR1 P-glycoprotein (Pgp), a member of the ATP-binding cassette family of transporters, is a transmembrane ATPase efflux pump for various lipophilic compounds, including many anti-cancer drugs. mAb UIC2, reactive with the extracellular moiety of Pgp, inhibits Pgp-mediated efflux. UIC2 reactivity with Pgp was increased by the addition of several Pgp-transported compounds or ATP-depleting agents, and by mutational inactivation of both nucleotide-binding domains (NBDs) of Pgp. UIC2 binding to Pgp mutated in both NBDs was unaffected in the presence of Pgp transport substrates or in ATP-depleted cells, whereas the reactivities of the wild-type Pgp and Pgps mutated in a single NBD were increased by these treatments to the level of the double mutant. These results indicate the existence of different Pgp conformations associated with different stages of transport-associated ATP hydrolysis and suggest trapping in a transient conformation as a mechanism for antibody-mediated inhibition of Pgp. 相似文献
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Hydrolysis of modified walleye pollock protein under the action of pepsin pancreatic and intestinal enzymes was studied under conditions in vitro and in vivo. It was found that the degree of dissolution of bonds is decreased in the experiments in vitro by 18.05-24.87%, in vivo by 34.2%, as compared to the experiments where casein was used. At the same time hydrolysis of oligo- and dipeptides realized in the intestine by amino- and dipeptidases is stimulated under the influence of the pollock protein by 16.07-53.7%. Therefore it is suggested that utilization of the protein studied depends on the capacity of peptidases to release dipeptides in separate acetylated or free dipeptides. Thus, for the sake of regulatory and adaptive changes of secretion of some digestive glands and especially enzymes, fixed on enterocyte brush edge, the necessary enzyme-substrate correspondence is provided, as a result of which hydrolysis of the pollock protein is achieved. 相似文献