C Murad | PubMed Health

PubMed1999

Programming features of the CLARION Multi-Strategy Cochlear Implant.

Because patient performance with multichannel cochlear implants varies widely, cochlear implant systems must address the diverse needs of patients during the postoperative fitting of the external equipment. This paper describes the processing strategies available with the CLARION Multi-Strategy Cochlear Implant and the different programming features available for optimization of these speech processing strategies. In addition, preliminary data are presented about the frequency of use of various fitting parameters with adult Simultaneous Analog Stimulation (SAS) and Continuous Interleaved Sampler (CIS) patients and pediatric CIS users. The data reveal that many of the programming features available to the clinician are useful with both the adult and pediatric populations and across strategies. The flexibility of both processing strategies and the programming options clearly contribute to the optimization of patient device fittings. Optimized device fittings, in turn, maximize patient performance.

Cochlear Implants↗

PubMedDate not supplied

Hyperactivated motility is coupled with interdependent modifications at axonemal and cytosolic levels in human spermatozoa.

Whether the motility characteristics of hyperactivated spermatozoa were determined by stable changes at the axonemal level and whether the presence of cytosolic factors was required for the expression of these changes was investigated. Different degrees of sperm hyperactivation were produced in Percoll-washed spermatozoa after incubation for 1 hour to 3 hours at 37 degrees C in Ham's F-10 supplemented with human blood plasma or fetal cord serum. Decomplemented fetal cord serum induced the highest percentage of hyperactivation (19 +/- 3%), followed by human plasma (13 +/- 2%). Fetal cord serum that was not decomplemented did not induce a level of hyperactivation (1.7 +/- 0.2%) significantly different from control levels (0.9 +/- 0.2%). Dialyzed fetal cord serum induced intermediate levels of hyperactivation (6 +/- 1%). The motility characteristics of demembranated sperm models of hyperactivated spermatozoa induced by decomplemented fetal cord serum and nonhyperactivated spermatozoa were compared by videomicroscopy and computer-assisted digital image analysis. After demembranation with Triton X-100 and reactivation of motility by Mg. adenosine triphosphate (Mg.ATP), hyperactivated and nonhyperactivated spermatozoa showed similar motility characteristics. However, hyperactivated spermatozoa that were demembranated and reactivated in cytosolic extracts from hyperactivated spermatozoa had significantly higher (P less than 0.05) linear velocity (33 +/- 4 mu/sec) and lower linearity (0.23 +/- 0.04) than control spermatozoa that were demembranated and reactivated in control cytosolic extracts (velocity = 24 +/- 1 mu/sec; linearity = 0.32 +/- 0.02). The data suggest that the expression of hyperactivated motility requires interdependent changes at the axonemal and cytosolic levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗