{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T03:18:51Z","timestamp":1790738331320,"version":"4.1.0"},"reference-count":0,"publisher":"American Society for Microbiology","issue":"10","license":[{"start":{"date-parts":[[1987,10,1]],"date-time":"1987-10-01T00:00:00Z","timestamp":560044800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.asm.org\/non-commercial-tdm-license"}],"content-domain":{"domain":["journals.asm.org"],"crossmark-restriction":true},"short-container-title":["Antimicrob Agents Chemother"],"published-print":{"date-parts":[[1987,10]]},"abstract":"<jats:p>Entry of antibiotics into phagocytes is necessary for activity against intracellular organisms. Therefore, we examined the uptake of five of the newer antibiotics--roxithromycin (RU 965), imipenem, cefotaxime, trimethoprim, and metronidazole--by human polymorphonuclear leukocytes (PMN). Antibiotic uptake by PMN was determined by a velocity gradient centrifugation technique and expressed as the ratio of the cellular concentration of antibiotic to the extracellular concentration (C\/E). Cefotaxime, like other beta-lactam antibiotics, was taken up poorly by phagocytes (C\/E less than or equal to 0.3). The metronidazole concentration within PMN was similar to the extracellular level. Imipenem bound rapidly to phagocytes (C\/E = 3), but cell-associated drug progressively declined during the incubation period. Trimethoprim was well concentrated by PMN (C\/E = 9 to 13), and uptake was unexpectedly greater at 25 degrees C than at 37 degrees C. The most striking finding was that roxithromycin was more avidly concentrated by PMN (C\/E = 34) than any other antibiotic we studied. Entry of roxithromycin into phagocytes was an active process and displayed saturation kinetics characteristic of a carrier-mediated membrane transport system. Ingestion of microbial particles by PMN slightly decreased the ability of these cells to accumulate roxithromycin (C\/E = 24 to 31). These studies identified two antibiotics, trimethoprim and especially roxithromycin, which are markedly concentrated within human PMN and may prove useful in treatment of infections caused by susceptible intracellular organisms.<\/jats:p>","DOI":"10.1128\/aac.31.10.1553","type":"journal-article","created":{"date-parts":[[2012,6,28]],"date-time":"2012-06-28T00:04:52Z","timestamp":1340841892000},"page":"1553-1557","update-policy":"https:\/\/doi.org\/10.1128\/asmj-crossmark-policy-page","source":"Crossref","is-referenced-by-count":66,"title":["Entry of roxithromycin (RU 965), imipenem, cefotaxime, trimethoprim, and metronidazole into human polymorphonuclear leukocytes"],"prefix":"10.1128","volume":"31","author":[{"given":"W L","family":"Hand","sequence":"first","affiliation":[{"name":"Veterans Administration Medical Center (Atlanta), Decatur, Georgia 30033."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"N","family":"King-Thompson","sequence":"additional","affiliation":[{"name":"Veterans Administration Medical Center (Atlanta), Decatur, Georgia 30033."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J W","family":"Holman","sequence":"additional","affiliation":[{"name":"Veterans Administration Medical Center (Atlanta), Decatur, Georgia 30033."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"235","container-title":["Antimicrobial Agents and Chemotherapy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/AAC.31.10.1553","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/AAC.31.10.1553","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,2,21]],"date-time":"2022-02-21T14:57:30Z","timestamp":1645455450000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.asm.org\/doi\/10.1128\/AAC.31.10.1553"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1987,10]]},"references-count":0,"journal-issue":{"issue":"10","published-print":{"date-parts":[[1987,10]]}},"alternative-id":["10.1128\/AAC.31.10.1553"],"URL":"https:\/\/doi.org\/10.1128\/aac.31.10.1553","relation":{},"ISSN":["0066-4804","1098-6596"],"issn-type":[{"value":"0066-4804","type":"print"},{"value":"1098-6596","type":"electronic"}],"subject":[],"published":{"date-parts":[[1987,10]]},"assertion":[{"value":"1987-10-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}