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T Yamashita

Publications and source records attributed to T Yamashita.

At least 19 recordsLinked to original sources
PubMed2026

Eribulin versus taxane as first-line chemotherapy combined with dual HER2 blockade in patients with HER2-positive locally advanced or metastatic breast cancer: final survival outcomes of the JBCRG-M06/EMERALD study.

BACKGROUND: The phase III JBCRG-M06/EMERALD study was the first to show noninferior progression-free survival (PFS) of eribulin to taxane, combined with dual human epidermal growth factor receptor 2 (HER2) blockade (trastuzumab plus pertuzumab), as a first-line treatment for HER2-positive locally advanced breast cancer or metastatic breast cancer (LABC/MBC). We report final survival outcomes and biomarker analyses of the EMERALD trial. PATIENTS AND METHODS: Patients with HER2-positive LABC/MBC were randomly assigned 1:1 to either eribulin or physician-choice taxane (docetaxel or paclitaxel), both combined with trastuzumab plus pertuzumab, as first-line chemotherapy. PFS and overall survival (OS) were assessed through 30 June 2023 for PFS and 31 December 2024 for OS. Survival outcomes were compared between the eribulin and taxane groups and according to circulating tumor DNA (ctDNA) detection of PIK3CA mutations (PIK3CAm+; E542K, E545K, H1047R, and N345K single nucleotide variants) or HER2 amplification (HER2 amp+; ERBB2 copy number >2.5). RESULTS: Median OS was 78.5 months [95% confidence interval (CI) 64.3-not reached (NR)] for eribulin and was NR for taxane, with a hazard ratio of 1.25 (95% CI 0.92-1.71, log-rank P = 0.19). The 60-month OS rates were 59.7% and 65.2% for eribulin and taxane, respectively. Median OS and 60-month OS rates were numerically lower in ctDNA PIK3CAm+ patients, and greater in ctDNA HER2 amp+ patients for all patients and with stratification by treatment group. There were no statistical interactions between treatment group with either ctDNA PIK3CAm or ctDNA HER2 amp status. Similar patterns were observed for PFS. CONCLUSION: Final survival analysis revealed that median OS exceeded 6 years with eribulin or physician-choice taxane, combined with trastuzumab plus pertuzumab, as first-line chemotherapy for HER2-positive LABC/MBC, with no significant differences between the two groups. ctDNA PIK3CAm+ status was a poor prognostic factor. ctDNA HER2 amp+ was associated with longer survival.

Aged↗
PubMed1979

A possible preferential inhibition of chemotaxis of polymorphonuclear neutrophils by a chemical modification.

The modification of neutrophils with amino group blocking reagents of different chemical specificities showed that dansyl chloride caused inhibition of chemotaxis without suppression of random movement. Dansylated neutrophils, like control cells, ingested bacteria. Neither the stimulated cyanide-insensitive respiration, nor lactate production during phagocytosis, was affected significantly by dansylation as compared with the inhibition of directed movement.

Acetone↗
PubMed1979

Adrenergic innervation in the Eustachian tube of guinea pigs.

We have succeeded in demonstrating for the first time adrenergic innervation in the Eustachian tube of guinea pigs. The approach was histochemical using the fluorescence method with glyoxylic acid. There was an apparent regional variation with a greater number of axon terminals in the pharyngeal area of the Eustachian tube as compared to the tympanic area.

Adrenergic Fibers↗
PubMed1979

Protein synthesized early after infection is linked to the termini of adenovirus type 2 DNA synthesized in vivo and in vitro.

The human adenovirus DNA genome contains a protein (CBP, or covalently bound protein) linked to each 5' terminus. To assess whether CBP is synthesized early, infected cells were incubated with hydroxyurea from 1 to 18 h postinfection, the hydroxyurea was removed, cycloheximide was added, and viral DNA was labeled with [3H]thymidine from 18 to 23 h postinfection. Removal of hydroxyurea at 18 h postinfection permits the synthesis of viral DNA, whereas cycloheximide maintains the block in late viral protein synthesis. Three lines of evidence are presented to show that viral 3H-labeled DNA prepared by this procedure was linked to CBP: (I) the DNA sedimented more rapidly than protein-free DNA (i.e., protinase treated) in neutral sucrose gradients containing guanidine hydrochloride; (ii) the DNA banded at a lower density than protein-free DNA in CsCl gradients containing guanidine hydrochloride; and (iii) neither the 3H-labeled DNA nor the end fragments produced by EcoRI digestion entered a 1.4% agarose gel during electrophoresis. These experiments are strong evidence that CBP is not a product of a late viral gene and is therefore the product of either an early viral gene or a cell gene. Experiments were performed to test whether CBP is attached to viral DNA synthesized in vitro by a soluble complex that synthesizes exclusively viral DNA as completed viral genomes in vitro. In vitro-labeled DNA was analyzed by velocity sedimentation, equilibrium sedimentation, and agarose gel electrophoresis as described above. Our results indicate that the majority of in vitro-synthesized DNA molecules were attached to CBP. These results, which indicate that CBP is synthesized early after infection and is attached to viral DNA labeled in vitro by a soluble replication complex, are consistent with the idea that CBP may play a role in viral DNA replication.

Adenoviruses, Human↗
PubMed1979

Distribution and frequency of gastrin cells in the digestive tract of the Japanese quail.

The gastrin cells of the Japanese quail were studied histologically and immunocytochemically. Cells reacting with antiserum to gastrin (gastrin cells) were demonstrated by the peroxidase-labelled antibody method and showed brownish cytoplasm. They also were stained argyrophil by the Grimelius' silver method. Gastrin cells were found in the epithelium of the pyloric region and small intestine and not in any other regions. They were the most numerous in the pyloric region (382.14 +/- 12.77/1.25mm2), next in the ileum (3.79 +/- 1.24/1.25mm2) and duodenum (2.93 +/- 0.62/1.25mm2), and the least in the jejunum (0.93 +/- 0.62/1.25mm2). Remarkable concentration of gastrin cells in the pyloric region has thus been demonstrated.

Animals↗
PubMed1979

Studies on auromomycin.

A new antitumor antibiotic, named auromomycin, was isolated from the culture broth of Streptomyces macromomyceticus, a macromomycin-producing strain. The antibiotic was recovered from the culture filtrate by salting out with ammonium sulfate and further purified by successive application of ion-exchange chromatography on Amberlite IRA-93 (Cl form) and DEAE-Sephadex (OH form), Gel filtration on Sephadex G-50 and hydrophobic chromatography on Octyl-Sepharose CL-4B. The antibiotic is an acidic polypeptide with a molecular weitht of 12,500 and an isoelectric point of pH 5.4 and consists of 16 different amino acids. It has characteristic absorption maxima at 273 nm and 357 nm in the ultraviolet spectrum and two minima at 280 nm and 350 nm in the optical rotatory dispersion spectrum. Auromomycin exhibits antibacterial activity not only against Gram-positive bacteria, but also Gram-negative bacteria. Antitumor activities of auromomycin were revealed against EHRLICH ascites carcinoma, ascites sarcoma 180, L1210 leukemia and LEWIS lung carcinoma. Auromomycin was found to be converted into macromomycin by adsorption chromatography on Amberlite XAD.

Amino Acids↗
PubMed1979

Biological activity of macromomycin.

Macromomycin (MCR) is a polypeptide antimuor antibiotic isolated from the culture broth of Streptomyces macromomyceticus. Antitumor activities of MCR were examined against three different tumor system, i.e., EHRLICH ascites carcinoma, L1210 leukemia and LEWIS lung carcinoma. Daily intraperitoneal treatment with MCR for 5 days showed a strong inhibition against EHRLICH ascites carcinoma. Both single and repeated intraperitoneal injections of MCR were effective over a wide dose range against intraperitoneally inoculated L1210 leukemia and MCR intravenously administered was also active against intravenously inoculated L1210 leukemia. Daily local subcutaneous injections of MCR produced the prolongation of life span of mice to which LEWIS lung carcinoma was subcutaneously inoculated with some cured mice, but daily intraperitoneal injections of MCR showed no activity. Single intravenous administration of MCR inhibited early LEWIS lung carcinoma, but not advanced LEWIS lung carcinoma. The combination of MCR with aracytidine, or cyclophosphamide showed a synergistic activity against L1210 leukemia. MCR was not inactivated by treatment with serum, although neocarzinostatin was markedly inactivated by the same treatment.

Animals↗