CO2 storage and release in the deep Southern Ocean on millennial to centennial timescales.

The cause of changes in atmospheric carbon dioxide (CO2) during the recent ice ages is yet to be fully explained. Most mechanisms for glacial-interglacial CO2 change have centred on carbon exchange with the deep ocean, owing to its large size and relatively rapid exchange with the atmosphere1. The Southern Ocean is thought to have a key role in this exchange, as much of the deep ocean is ventilated to the atmosphere in this region2. However, it is difficult to reconstruct changes in deep Southern Ocean carbon storage, so few direct tests of this hypothesis have been carried out. Here we present deep-sea coral boron isotope data that track the pH-and thus the CO2 chemistry-of the deep Southern Ocean over the past forty thousand years. At sites closest to the Antarctic continental margin, and most influenced by the deep southern waters that form the ocean's lower overturning cell, we find a close relationship between ocean pH and atmospheric CO2: during intervals of low CO2, ocean pH is low, reflecting enhanced ocean carbon storage; and during intervals of rising CO2, ocean pH rises, reflecting loss of carbon from the ocean to the atmosphere. Correspondingly, at shallower sites we find rapid (millennial- to centennial-scale) decreases in pH during abrupt increases in CO2, reflecting the rapid transfer of carbon from the deep ocean to the upper ocean and atmosphere. Our findings confirm the importance of the deep Southern Ocean in ice-age CO2 change, and show that deep-ocean CO2 release can occur as a dynamic feedback to rapid climate change on centennial timescales.

Daytime diurnal curve comparison between the fixed combinations of latanoprost 0.005%/timolol maleate 0.5% and dorzolamide 2%/timolol maleate 0.5%.

PURPOSE: The diurnal efficacy and safety of the fixed combinations of latanoprost/timolol given once daily vs dorzolamide/timolol given twice daily in primary open-angle glaucoma or ocular hypertensive patients. DESIGN: A double-masked, two-centre, crossover comparison. RESULTS: In 33 patients, the mean diurnal IOP (0800-2000, measured every 2 h) for latanoprost/timolol fixed combination was 17.3+/-2.2 mmHg and for dorzolamide/timolol, the fixed combination was 17.0+/-2.0 mmHg (P = 0.36). Additionally, there was no statistical difference for individual time points following a Bonferroni correction. A bitter taste was found more frequently with the dorzolamide/timolol fixed combination (n = 6) than the latanoprost/timolol fixed combination (n = 0) (P = 0.040), while the latanoprost/timolol fixed combination demonstrated more conjunctival hyperaemia (n = 9) than the dorzolamide/timolol fixed combination (n = 2) (P = 0.045). One patient was discontinued early from the dorzolamide/timolol fixed combination due to elevated IOP. CONCLUSION: This study suggests that the daytime diurnal IOP is not statistically different between the dorzolamide/timolol fixed combination and latanoprost/timolol fixed combination in primary open-angle glaucoma and ocular hypertensive patients.

A pilot study of melphalan, tumor necrosis factor-alpha and 41.8 degrees C whole-body hyperthermia.

PURPOSE: To evaluate the feasibilitv of sequencing (based on preclinical modeling) tumor necrosis factor-a (TNF) at two dose levels with melphalan (L-PAM) and 41.8 C whole-body hyperthermia (WBH) for 60 min. PATIENTS AND METHODS: Nine patients with refractory cancer were treated from October 1995 to June 1997. The study encompassed a total of 20 trimodality treatment courses. Three patients were treated at TNF dose level I (50 microg/m2) and six patients were treated at TNF dose level II (100 microg/m2). TNF was delivered as a 24-h intravenous infusion, 48 h prior to the combination of L-PAM and WBH; L-PAM was given over 10 min at target temperature at a dose of 17.5 mg/ m2 based on a previous phase I WBH/L-PAM trial. WBH was administered with an Aquatherm radiant heat device. RESULTS: Myelosuppression was the major toxicity associated with therapy, but there were no instances of bleeding or neutropenic fevers. Grade 3 thrombocytopenia was seen with 15% of treatments. Regarding absolute neutrophil count, 15% of treatments were associated with grade 3 toxicity, and 45% with grade 4 toxicity, and regarding white blood cell count, 50% of treatments were associated with grade 3 toxicity and 10% with grade 4 toxicity. The myelosuppression observed was equivalent to that seen in our earlier phase I study of WBH and L-PAM (without TNF). Only mild toxicities (grade 1 or 2) were associated with TNF; these were seen with <25% of treatments and included nausea, vomiting, diarrhea, fevers, and headache. There were no instances of hypotension. There was no relationship between toxicities observed and the two TNF dose levels. Mild WBH toxicities were seen with less than 15% of treatments; these included nausea, vomiting, and herpes simplex I. Responses included two complete remissions (malignant melanoma, TNF dose level I; breast cancer, TNF dose level II), and two disease stabilizations (both malignant melanoma, TNF dose level I). CONCLUSION: We conclude that the combination of TNF, L-PAM, and WBH is well tolerated at the dose levels studied. The clinical results justify further clinical investigation for this trimodality treatment approach.

The efficacy and safety of diclofenac 0.1% versus prednisolone acetate 1% following trabeculectomy with adjunctive mitomycin-C.

BACKGROUND AND OBJECTIVE: To evaluate the efficacy and safety of diclofenac 0.1% versus prednisolone acetate 1% following trabeculectomy with adjunctive mitomycin-C. PATIENTS AND METHODS: The authors prospectively randomized chronic open-angle glaucoma patients who underwent trabeculectomy with adjunctive mitomycin-C to receive postoperatively either diclofenac 0.1% or prednisolone acetate 1% 4 times daily, to be tapered as inflammation resolved. RESULTS: In the diclofenac group (n = 14), the preoperative intraocular pressure of 30.4 +/- 13.1 decreased to 12.4 +/- 6.5 mm Hg at 6 months postoperatively. In the prednisolone acetate group (n = 12), the preoperative intraocular pressure decreased from 29.1 +/- 10.4 to 12.8 +/- 4.2 mm Hg at 6 months postoperatively (P = .85). The average number of medicines used 6 months postoperatively was 0.50 +/- 0.8 in the diclofenac group and 0.24 +/- 0.6 in the prednisolone acetate group (P = .36). Adverse events were similar between groups (P = .51). One patient in the diclofenac group underwent reoperation at 1 month due to uncontrolled intraocular pressure. CONCLUSIONS: This study shows that following trabeculectomy with adjunctive mitomycin-C, a similar intraocular pressure result may be expected when either diclofenac or prednisolone acetate is prescribed postoperatively for intraocular inflammation.

Phase I clinical trial of melphalan and 41.8 degrees C whole-body hyperthermia in cancer patients.

PURPOSE: To evaluate the biologic interactions and toxicities of melphalan (L-PAM) combined with 41.8 degrees C whole-body hyperthermia (WBH) for 60 minutes. PATIENTS AND METHODS: Sixteen patients with refractory cancer were treated (May 1992 to May 1995) with WBH alone during week 1) thereafter patients were randomized to receive either L-PAM alone on week 2 and L-PAM plus WBH on week 5, or the reverse sequence. Patients who demonstrated clinical improvement received WBH plus L-PAM monthly. Dose levels of L-PAM were 10 mg/m2 (n = 3), 15 mg/m2 (n = 3), 17.5 mg/m2 (n = 6), and 20 mg/m2 (n = 4). L-PAM was administered at target temperature; WBH was administered with an Aquatherm radiant-heat device (patent pending; Cancer Research Institute, New York, NY). RESULTS: Comparisons of mean WBC count and platelet nadirs for L-PAM alone and L-PAM plus WBH demonstrated that the addition of WBH resulted in nadir counts that were, on average, 25% lower. There were no instances of febrile neutropenia or bleeding. Toxicities allowed for escalation of L-PAM to 20 mg/m2; all four patients at this level experienced grade 4 myelosuppression. No significant myelosuppression was observed at 10 and 15 mg/m2. Grade 3 myelosuppression was observed in two of six patients at 17.5 mg/m2. Responses included complete remission (CR) of pancreatic cancer (10 mg/m2), partial remission (PR) of malignant melanoma in two patients (20 mg/m2), and transient clinical and/or serologic improvement in five patients. The pharmacokinetics of L-PAM were not altered by WBH. Observed cytokine induction by WBH is also discussed in detail. CONCLUSION: We conclude that L-PAM with 41.8 degrees C WBH is well tolerated. Clinical results are consistent with preclinical predictions and provide a foundation for second-generation trials now in progress.