Technological Innovation and Adaption: Tyndrum Lead Mine and the German Managers, 1838 to 1865

In 1838 the second Marquis of Breadalbane, having failed to lease the mineral rights at Tyndrum lead mine on the Campbell family estate in the southern Scottish highlands, made a decision to work the mine himself. When he began his operation, the mine was nearing exhaustion and what little productivity remained was hindered by increasingly complex mineralisation. The Marquis, however, was convinced that the mine could still produce great wealth; he looked to Germany for expertise and employed a succession of German mining engineers to manage his ailing operation. The survival of their monthly progress reports and other documentation offers a unique perspective on the Scottish lead mining industry and the adaptive strategies, in terms of technological innovation and mining practices, that the Germans employed to prolong the venture's economic survival

Treatment with lamivudine, zidovudine, or both in hiv-positive patients with 200 to 500 cd4+ cells per cubic millimeter

Background. The reverse-transcriptase inhibitor lamivudine has in vitro synergy with zidovudine against the human immunodeficiency virus (HIV). We studied the activity and safety of lamivudine plus zidovudine as compared with either drug alone as treatment for patients with HIV infection, most of whom had not previously received zidovudine. Methods. Three hundred sixty-six patients with 200 to 500 CD4+ cells per cubic millimeter who had received zidovudine for four weeks or less were randomly assigned to treatment with one of four regimens: 300 mg of lamivudine every 12 hours; 200 mg of zidovudine every 8 hours; 150 mg of lamivudine every 12 hours plus zidovudine; or 300 mg of lamivudine every 12 hours plus zidovudine. The study was double-blind and lasted 24 weeks, with an extension phase for another 28 weeks. Results. Over the 24-week period, the low-dose and high-dose regimens combining lamivudine and zidovudine were associated with greater increases in the CD4+ cell count (P=0.002 and P=0.015, respectively) and the percentage of CD4+ cells (P<0.001 for both) and with greater decreases in plasma levels of HIV type 1 (HIV-1) RNA (P<0.001 for both) than was treatment with zidovudine alone. Combination therapy was also more effective than lamivudine alone in lowering plasma HIV-1 RNA levels and increasing the percentage of CD4+ cells (P<0.001 for all comparisons), and these advantages persisted through 52 weeks. Adverse events were no more frequent with combination therapy than with zidovudine alone. Conclusions. In HIV-infected patients with little or no prior antiretroviral therapy, treatment with a combination of lamivudine and zidovudine is well tolerated over a oneyear period and produces more improvement in immunologic and virologic measures than does treatment with either agent alone. (N Engl J Med 1995;333:1662-9.

A comparison of stavudine, didanosine and indinavir with zidovudine, lamivudine and indinavir for the initial treatment of HIV-1 infected individuals: Selection of thymidine analog regimen therapy (Start II)

Objective: Comparison of stavudine (d4T), didanosine (ddl) and indinavir (IDV) with zidovudine (ZDV), lamivudine (3TC) and IDV in HIV-1 infected patients. Design: Randomized, open-label. Setting: Fourteen HIV Clinical Research Centers. Patients: Two-hundred and five patients with less than 4 weeks antiretroviral treatment, naive to 3TC and protease inhibitors and with CD4 cell counts ≥ 200 x 10 6/l and plasma HIV-1 RNA levels ≥ 10 000 copies/ml. Interventions: Stavudine 40 mg and ddl 200 mg twice daily plus IDV 800 mg every 8 h compared with ZDV 200 mg every 8 h or 300 mg twice daily, 3TC 150 mg twice daily plus IDV. Main outcome measures: The proportion of patients with plasma HIV-1 RNA levels \u3c 500 copies/ml and ≤ 50 copies/ml and changes in CD4 cell counts were compared. Results: In an analysis of the primary endpoint, 61% of patients on d4T + ddl + IDV and 45% of patients on ZDV+ 3TC + IDV had all HIV-1 RNA values obtained between weeks 40 and 48 \u3c 500 copies/ml [95% confidence interval (Cl) for the difference between proportions, 1.7-30.3%; P = 0.038]. In an intent-to-treat analysis, the percentage of all patients randomized with all HIV-1 RNA levels \u3c 500 copies/ml between 40 and 48 weeks were 53% for the d4T + ddl + IDV arm and 41% for the ZDV + 3TC + IDV arm (95% Cl, -1.4% to 25.7%; P = 0.068). At 48 weeks 41% and 35% were ≤ 50 copies/ml for the stavudine- and ZDV-containing arms respectively (P \u3e 0.2). The median time-weighted average increases in CD4 cells count over 48 weeks were 150 x 10 6/l cells for the d4T arm and 106 x 10 6/l cells for the ZDV arm (P = 0.001). The occurrence of serious adverse events was not significantly different between arms. Conclusion: The combination of stavudine, ddl and IDV resulted in potent antiretroviral effects over a 48-week period, comparable or superior to zidovudine, 3TC and IDV supporting the use of stavudine, ddl and a protease inhibitor as an initial antiretroviral treatment. (C) 2000 Lippincott Williams and Wilkins