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Biomedical subjects

I Buchwald

Publications and source records attributed to I Buchwald.

11 recordsLinked to original sources
PubMed1978

Localization of host poly(A)+ mRNA in the ribosome profile of mengovirus-infected Ehrlich ascites tumor cells.

The distribution of poly(A)+ mRNA among polysomes, monosomes, and ribosome-free supernatant fractions after mengovirus infection of Ehrlich ascites tumor (EAT) cells was investigated employing sucrose gradient centrifugation of their corresponding postnuclear supernatants. Poly(A)+ mRNA was isolated from sucrose gradient fractions and quantitated in a cell-free protein synthesizing system from uninfected EAT cells. It was also localized by annealing [3H]-poly(U) to the poly(A)-tracts of mRNA present in the sucrose gradient fractions. Both experiments revealed a gradual shift of host poly(A)+ mRNA from large to small polysomes and monosomes, respectively, with the time postinfection. The greatest part of host template RNA appears to remain ribosome-bound and only a fraction seems to be detached from the ribosomes in the course of mengovirus infection. At the end of the infectious cycle, 8 h postinfection, approximately 70% of the poly(A)+ mRNA detected in uninfected cells is still biologically active, but not translated in vivo, in agreement with data from the [3H]poly(U)hybridization experiment.

Animals↗
PubMed1977

2'(3'),5'-ADP inhibits initiation-dependent protein synthesis in a cell-free system from Ehrlich ascites tumor cells.

When tested in a poly(U)-dependent polyphenylalanine synthesizing system and in a postnuclear supernatant, both derived from Ehrlich ascites tumor cells, 2'(3'),5'-ADP did not affect chain elongation of polypeptide synthesis. In a cell-free system which was dependent on initiation and programmed by natural mRNA, however, the amino acid incorporating activity was suppressed to about 10% of the control in the presence of 1 mM 2'(3'),5'-ADP. The inhibitor was shown not to interfere with the attachment of poly(U) to the small ribosomal subunit and with the formation of mRNA-80S ribosome complexes in a complete protein synthesizing system. The subsequent attachment of a 40S ribosomal subunit to the mRNA-80S ribosome complex and the formation of polysomes, however, was depressed by the inhibitor. The experimental results suggest that 2',(3'),5'-ADP inhibits initiation-dependent protein synthesis between monosome formation and the formation of the first peptide bond(s).

Adenosine Diphosphate↗
PubMed1977

Coding capacity of poly(A)+mRNA isolated from mengovirus-infected Ehrlich ascites tumor cells.

Total poly (A)+mRNA was isolated from mengovirus-infected Ehrlich ascites tumor cells at various times postinfection and quantitated in a cell-free system derived from uninfected ascites cells. Basic proteins were separated from acidic proteins by carboxymethyl cellulose chromatography. At the end of the infectious cycle, 8h postinfection, the cellular contents of most mRNAs coding for basic ribosomal proteins are still between 70 and 90 percent of those measured at the beginning of infection or in uninfected cells. On the basis of this result, the rapid shutoff of host protein synthesis after mengovirus infection of Ehrlich ascites tumor cells cannot be the consequence of the inactivation of host template RNA.

Animals↗
PubMedDate not supplied

Oral ondansetron: an effective ambulatory complement to intravenous ondansetron in the control of chemotherapy-induced nausea and vomiting in children.

One hundred children with non-central nervous system malignancies received ondansetron at initiation of chemotherapy and every 8 hours for 5 days after cisplatin-containing therapy and for 3 days after other chemotherapy. Ondansetron was administered orally except with the intravenous chemotherapy. For the chemotherapy days, 72 of 93 children (76%) had complete or major control of vomiting on their worst day, 25% with cisplatin-containing protocols, 60% with ifosfamide-containing protocols, and 82% with other protocols. For the overall period, 71 of 93 children (76%) reported complete or major control of vomiting on the worst day, 14% with cisplatin, 60% with ifosfamide, and 83% with other chemotherapy. All had mild or no nausea. Of the 355 chemotherapy days, 228 children (64%) were emesis free, 40% with cisplatin, 60% with ifosfamide, and 68% with other regimens. Of the overall period (541 days), 393 days were emesis free, 45% with cisplatin, 71% with ifosfamide, and 86% with other regimes. Sixty-nine patients were not hospitalized, and oral ondansetron was given when chemotherapy was completed. Of the 241 ambulatory chemotherapy days, 178 (74%) were emesis free. No significant toxicity was encountered. Oral ondansetron reduced hospitalization without reducing antiemetic efficiency in children.

Administration, Oral↗