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C Rochette

Publications and source records attributed to C Rochette.

4 recordsLinked to original sources

Linkage study of chronic childhood-onset spinal muscular atrophy (SMA): confirmation of close linkage to D5S39 in French Canadian families.

Chronic childhood-onset spinal muscular atrophy (SMA) is, after Duchenne muscular dystrophy, the most common neuromuscular disorder in childhood. Recent linkage analyses have mapped this disease to 5q12-5q14. We show that chronic SMA (Types II and III) is tightly linked to the marker locus D5S39 (Zmax = 5.47 at theta = 0.02) in eight French Canadian families. In contrast to previously published results, we do not observe close linkage between chronic SMA and D5S6 (Zmax = 0.34 at theta = 0.18) or D5S78 (Zmax = 0.25 at theta = 0.21). Last, we present a family that appears to be discordant for this localization but may represent the first example of an incompletely penetrant individual.

Canada

[Multivariate study of auditory perception using multi-electrode cochlear implants].

The goal of this study was to determine the influence of auditory and cognitive factors in hearing or listening mechanisms with the Nucleus multielectrode cochlear implant. Accordingly, hearing sensitivity, psycho-acoustical masking functions and measures of temporal resolution were obtained from 14 adults with acquired deafness. In addition, six measures of open-set speech discrimination were introduced to represent a possible contribution of cognitive factors. Results indicated the contribution of both auditory and cognitive factors to speech understanding. Cognitive factors were most influential. Differences were also found in the relative importance of various cognitive factors, both before and after an intensive aural rehabilitation program. Initially, subjects relied more heavily on their ability to make efficient use of the linguistic redundancy of speech. At the end of the program, they paid more attention to speech acoustics, as a result of enhanced auditory spectral analysis and temporal resolution at about 2 kHz.

Adolescent

Apolipoprotein B-100: immunolocalization and synthesis in human intestinal mucosa.

Despite the evidence that the human small intestine produces two separate species of apoB mRNA encoding for B-100 and B-48, there is a paucity of data concerning the expression of the latter form in this organ. Using a high resolution immunogold approach, with specific polyclonal antibodies and a panel of monoclonal antibodies (2D8, 3A10, 4G3), both forms of apoB (B-48 and B-100) were revealed over enterocytes of pediatric intestinal samples. Intense labeling was observed over microvilli, apical smooth membrane vesicles, multivesicular bodies, the basolateral membrane, as well as the trans Golgi region. Only low labeling was found over the rough endoplasmic reticulum (rER). Similar patterns of apoB distribution characterized both duodenal and jejunal regions. The presence of labeling over the Golgi apparatus and rER suggests a synthetic activity of both forms of apoB by the epithelial cells. To test this hypothesis, human intestine was incubated with [3H]leucine, homogenized, and subjected to immunoprecipitation for apoB. Immunoprecipitates contained radioactivity mainly in apoB-48 with relatively small amounts in apoB-100 when examined by NaDodSO4-polyacrylamide gel electrophoresis. These findings were further supported by the biochemical determination of apoB-100 and apoB-48 in chylomicron particles isolated from thoracic duct lymph of a human donor. Taken together, our data suggest that the human intestine is able to synthesize and to express the apoB-100.

Apolipoprotein B-100