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N Lane

Publications and source records attributed to N Lane.

62 records · Page 4Linked to original sources

Fluid transport in the rabbit gallbladder. A combined physiological and electron microscopic study.

The fine structure of the rabbit gallbladder has been studied in specimens whose functional state was undetermined, which were fixed either in situ or directly after removal from the animal; in specimens whose rate of fluid absorption was determined, either in vivo or in vitro, immediately prior to fixation; and in specimens from bladders whose absorptive function was experimentally altered in vitro. Considerable variation was found in the width of the epithelial intercellular spaces in the bladders whose functional state was undefined. In bladders known to be transporting fluid, either in vivo or in vitro, the intercellular spaces were always distended, as were the subepithelial capillaries. This distension was greatest in bladders which had been functioning in vitro. When either Na(+) or Cl(-) was omitted from the bathing media, there was no fluid transport across the wall of the gallbladder studied in vitro. The epithelial intercellular spaces of biopsies taken from several bladders under these conditions were of approximately 200 A width except for minor distension at the crests of mucosal folds. The addition of the missing ion rapidly led to the reestablishment of fluid transport and the distension of the intercellular spaces throughout most of the epithelium of these bladders. Studies of sodium localization (by fixation with a pyroantimonate-OsO(4) mixture) showed high concentrations of this ion in the distended intercellular spaces. Histochemical studies of ATPase activity showed that this enzyme was localized along the lateral plasma membrane of the epithelial cells. The analogy is drawn between the structure of the gallbladder mucosa and a serial membrane model proposed by Curran to account for coupled solute-solvent transport across epithelia. It is concluded that the intercellular compartment fulfills the conditions for the middle compartment of the Curran model and that active transport of solute across the lateral plasma membrane into the intercellular space may be responsible for fluid absorption by the gall bladder.

Adenosine Triphosphatases↗

A phase I-phase II study of vinorelbine with cisplatin, 5-fluorouracil, and leucovorin for advanced non-small cell lung cancer.

PURPOSE: The combination of cisplatin, 5-fluorouracil, and leucovorin (PFL) has been reported to have a 29% response rate in advanced non-small cell lung cancer. Vinorelbine, a semi-synthetic vinca alkaloid, has also been reported to have single-agent activity in this disease. We designed a phase I-II study in which escalating doses of vinorelbine were added to PFL to define the dose-limiting toxicity and maximum tolerated dose of vinorelbine, and to determine the response rate and survival at the recommended phase II dose. PATIENTS AND METHODS: This study enrolled patients between December 1991 and August 1993. Eligibility criteria included histologically or cytologically documented stage III or IV non-small cell lung cancer, measurable or evaluable disease, and no prior chemotherapy. Treatment consisted of escalating doses of vinorelbine (starting at 20 mg/m2) on days 1 and 6, cisplatin 100 mg/m2 on day 2, and 5-fluorouracil as a continuous infusion at 800 mg/m2/day for 4 days (days 2-5) with leucovorin 100 mg orally every 4 hours on days 1 through 5. Cycles were repeated every 21 days. RESULTS: Forty patients were treated during the study. The median age of the patients was 58 (range, 33-75) and 36 patients had a performance status of 0 or 1. Dose-limiting neutropenia was observed in both patients treated with vinorelbine at 25 mg/m2. At the recommended phase II vinorelbine dose of 20 mg/m2 on days 1 and 6, myelosuppression remained the most common toxicity, with 22 patients (55%) having grade 4 neutropenia. Fifteen patients (38%) required hospital admission for neutropenic fever; two died of neutropenic sepsis. Of 33 patients evaluated, 2 patients achieved a complete response and 10 patients achieved a partial response (overall response rate, 30%; 36% of the evaluated patients). Median survival was 10.4 months for the entire cohort (16.4 months for those with stage III disease and 9.6 months for patients with stage IV disease) and 1-year survival was 45%. The overall median time to progression was 8.1 months. CONCLUSIONS: The maximum tolerated dose of vinorelbine given on days 1 and 6 with PFL is 20 mg/m2; myelosuppression is the dose-limited factor. The response rate is similar to rates observed in prior studies of combination chemotherapy, but the median survival of patients with stage IV disease exceeds that of many other regimens.

Adenocarcinoma↗