Optimized speech understanding with the continuous interleaved sampling speech coding strategy in patients with cochlear implants: effect of variations in stimulation rate and number of channels.

The purpose of this study was to investigate the effect of systematic variations in stimulation rate and number of channels on speech understanding in 13 patients with cochlear implants who used the continuous interleaved sampling speech coding strategy. Reducing the stimulation rate from 1,515 to 1,730 pulses per second per channel to 600 pulses per second per channel resulted in decreased overall performance; the understanding of monosyllables and consonants was more affected than the understanding of vowels. Reducing the number of active channels below 7 or 8 channels decreased speech understanding; the identification of vowels and monosyllables was most affected. We conclude that vowel recognition with the continuous interleaved sampling strategy relies on spectral cues more than on temporal cues, increasing with the number of active channels, whereas consonant recognition is more dependent on temporal cues and stimulation rate.

Prospective evaluation of vitamin E for hot flashes in breast cancer survivors.

PURPOSE: Hot flashes represent a substantial clinical problem for some breast cancer survivors. Although estrogen or progesterone preparations can alleviate these symptoms in many patients, concern remains regarding the use of hormonal preparations in such women. Thus, there is a perceived need for nonhormonal treatments for hot flashes for breast cancer survivors. Based on anecdotal evidence that vitamin E was helpful, we designed a trial to investigate this matter. METHODS: We developed and conducted a placebo-controlled, randomized, crossover trial where, after a 1 week baseline period, patients received 4 weeks of vitamin E 800 IU daily, then 4 weeks of an identical-appearing placebo, or vice versa. Diaries were used to measure potential toxicities and hot flashes during the baseline week and the two subsequent 4-week treatment periods. RESULTS: The 120 patients evaluated for toxicity failed to show any. The 105 patients who finished the first treatment period showed a similar reduction in hot flash frequencies (25% v 22%; P = .90) for the two study arms. A crossover analysis, however, showed that vitamin E was associated with a minimal decrease in hot flashes (one less hot flash per day than was seen with a placebo) (P < or = .05). At the study end, patients did not prefer vitamin E over the placebo (32% v 29%, respectively). CONCLUSION: Although this trial was able to show a statistically significant hot flash reduction with vitamin E compared to a placebo, the clinical magnitude of this reduction was marginal.

Pancreatic cancer and primary care providers.

Pancreatic cancer is a relatively uncommon neoplasm for which long-term survival is unusual. Early diagnosis can lead to prolonged survival, because successful treatment is possible with surgical resection of stage 1 tumors. However, clinical findings are nonspecific and diagnosis usually occurs at advanced stages. Radiologic and laboratory techniques can help to identify patients earlier in the course of the disease. To detect tumors in early stages, efficient and cost-effective application of clinical, laboratory, and radio-logic methods should be used. But the primary care provide must understand the general characteristics of pancreatic cancer.

Gall bladder distention in newborns.

Three cases of gall bladder distention in asphyxiated newborns are described. Clinical and ultrasound examination showed this to be a benign, transient phenomenon. A causal relation between tissue hypoxia and gall bladder distention is proposed.

Differential reduction by caffeine of adriamycin induced cell killing and cell cycle delays in Chinese hamster V79 cells.

Exponentially growing Chinese-hamster V79-cells were treated with various doses of adriamycin (ADR) for 1 hr in the presence or absence of 2 mM caffeine and were subsequently incubated for 24 hr in fresh medium with or without caffeine (2 mM) before plating to assay for survival. The results indicated a reduction in killing when caffeine was present during treatment with ADR (e.g., reduction in killing from 0.03 to 0.3 after exposure to 0.5 microgram/ml ADR). This reduction in killing was even more pronounced after a 24 hr treatment with ADR in the presence of caffeine (e.g., reduction from 0.005 to 0.5 after exposure to 0.08 microgram/ml ADR). Incubation with caffeine after ADR treatment (1 hr) caused only a comparably small increase in cell survival. Presence of caffeine either simultaneously or after treatment with ADR caused a reduction of the inhibition of growth and mean-cell-volume increase, and a reduction of the accumulation of cells in G2-phase. Qualitatively similar results were also obtained after continuous treatment with ADR in the presence or absence of caffeine. Reduction in growth inhibition and accumulation of cells in G2-phase was observed under conditions only slightly affecting cell survival, thus suggesting that caffeine may affect these two phenomena by independent mechanisms. Flow cytometry measurement of the intracellular ADR content indicated a reduction in the presence of caffeine. Furthermore, post-treatment incubation with caffeine was found to increase the rate of decay of ADR-related fluorescence. Quantitative comparison between the effect of caffeine in the intracellular ADR accumulation and cell survival suggested that the observed reduction in killing could be attributed to a decrease in the intracellular drug levels. The reduction by caffeine of the ADR-induced cell cycle delays is attributed to either the decrease in the intracellular ADR dose in the presence of caffeine, or to an effect of caffeine similar to that exerted after exposure of cells to ionizing radiation. Trifluoperazine, which had only a small effect on cell survival of cells treated with ADR alone, potentiated killing when cells were treated with ADR in the presence of caffeine. This effect can be partly attributed to the observed modification in the intracellular ADR content under these conditions but, as a quantitative comparison suggests, other effects might also be involved.

Enhancement of adriamycin-induced killing after delayed plating of plateau-phase V79-cells.

Unfed plateau-phase cultures of Chinese hamster V79-cells were treated for 1 h with various amounts of adriamycin in the range between 0 and 10 micrograms ml-1 and subsequently either immediately trypsinized and plated to assay for survival, or reincubated in medium collected from replicate plateau-phase cultures and returned to the incubator for various periods of time before plating. Significantly less killing was observed, for the same adriamycin dose, in cells treated in the plateau-phase and plated immediately thereafter as compared to cells treated while actively growing. When cell trypsinization and plating was delayed for up to 22 h, a significant increase in killing was observed, and the survival curve obtained approached that observed after treatment with adriamycin of growing cells. Initially almost exponential kinetics were observed for this potentiation of adriamycin-induced cell killing with a t37 of approximately 2 h. Cell survival was still decreasing after 22 h of post-treatment incubation in the plateau phase, with no clear indication for approaching a plateau. However, longer incubations, to establish a plateau, were not possible due to degeneration of the cultures. Flow cytometry measurements of the intracellular adriamycin content showed only a small difference between exponentially growing and plateau-phase cells despite the significant differences in the number of cells per culture at the time of treatment. The rate at which adriamycin-related fluorescence decayed after adriamycin treatment was slightly higher for cells trypsinized and exposed to fresh medium than for cells kept in the plateau-phase. The results indicate the importance of the physiological state and the post-treatment incubation conditions of cells for the final effect of adriamycin on survival.

High-dose methotrexate with citrovorum factor and vincristine in the treatment of malignant mesothelioma.

The incidence of malignant mesothelioma has increased greatly in the last 40 years. Current and recent past exposure to asbestos is expected to substantially increase this incidence. We report nine cases of malignant mesothelioma which temporarily responded to treatment with high-dose methotrexate-citrovorum rescue and vincristine. Further clinical trials of high-dose methotrexate with citrovorum rescue appear indicated in this disease.

Megakaryocytic leukaemia as a phase of myeloproliferative disorders.

2 cases of megakaryocytic leukaemia are presented as a variant of myeloproliferative disorders. The uncontrolled proliferation of the megakaryocyte-platelet cell line occurred after splenectomy and treatment of blastic phase. Applicability of the term megakaryocytic leukaemia is discussed as well as its relationship to similar disorders. It is suggested that an extensive neoplastic proliferation of megakaryocytes with abnormal maturation and thereby formation of large dysplastic platelets in extramedullary organs especially the liver in the end stage of myelofibrosis is a possible mechanism for this disorder. Treatment with platelet-pheresis may be an effective part of therapy.