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C Bettencourt

Publications and source records attributed to C Bettencourt.

4 recordsLinked to original sources

Population genetics of wild-type CAG repeats in the Machado-Joseph disease gene in Portugal.

OBJECTIVE: To gain insights on the molecular mechanisms of mutation that led to the emergence of expanded alleles in the MJD gene, by studying the behavior of wild-type alleles and testing the association of its distribution with the representation of the disease. METHODS: The number of CAG motifs in the MJD gene was determined in a representative sample of 1000 unrelated individuals. Associations between the repeat size and the epidemiological representation of MJD were tested. RESULTS: The allelic profile of the total sample was in the normal range (13-41 repeats), with mode (CAG)23. No intermediate alleles were present. Allelic size distribution showed a negative skew. The correlation between the epidemiological representation of MJD in each district and the frequency of small, medium and large normal alleles was not significant. Further correlations performed grouping the districts also failed to produce significant results. CONCLUSIONS: The absence of association between the size of the repeats and the representation of MJD demonstrates that prevalence is not an indirect reflection of the frequency of large normal alleles. Globally the results obtained are in accordance with a model that postulates the occurrence of a few mutations on the basis of most of the MJD cases worldwide.

Ataxin-3↗

Analysis of Y-chromosome variability and its comparison with mtDNA variability reveals different demographic histories between islands in the Azores Archipelago (Portugal).

We determined the Y-chromosomal composition of the population of the Azores Islands (Portugal), by analyzing 20 binary polymorphisms located in the non-recombining portion of the Y-chromosome (NRY), in 185 unrelated individuals from the three groups of islands forming the Archipelago (Eastern, Central and Western). Similar to that described for other Portuguese samples, the most frequent haplogroups were R1(xR1b3f) (55.1%), E(xE3a) (13%) and J (8.6%). Principal components analysis revealed a Western European profile for the Azorean population. No significant differences between Azores and mainland Portugal were observed. However, the haplogroup distribution across the three groups of islands was not similar (P<0.003). The Western group presented differences in the frequencies of haplogroups R1, E(xE3a) and I1b2 (27.3%, 22.7% and 13.6%, respectively) when compared to the other two groups. An assessment of the NRY variability, and its comparison with mitochondrial DNA (mtDNA) variability, was further evidence of the differential composition of males during the settlement of the three groups of islands, contrary to what has been previously deduced for the female settlers using mtDNA data.

Base Sequence↗

Work hardening: past, present, and future--the work programs special interest section national work-hardening outcome study.

OBJECTIVES: A review of outcome research conducted between 1982 and 1992 revealed return-to-work rates for industrial rehabilitation programs that ranged from 50% to 88%. Variations in outcome statistics appeared to reflect discrepancies in factors such as type of research design, initial characteristics of the client sample, and clients excluded from the study group. METHOD: A work-hardening outcome study involving 36 programs was conducted by the Work Programs Special Interest Section to address questions left unanswered by existing studies regarding (a) rates of program nonacceptance or noncompletion, (b) basic client characteristics and outcome, (c) length of disability and outcome, (d) breakdown of client disposition after program completion, and (e) program characteristics and return to work. RESULTS: Findings included the following: (a) 11.5% of clients were not accepted into work hardening and 24.6% did not complete the program; (b) outcome was not related to client age, gender, area of injury, or physical demand level of job before injury; (c) as duration of disability increased, return to work decreased significantly; (d) at discharge, 48.2% of clients returned to the usual and customary job and 30.5% to alternate or modified work, whereas 13.6% were referred to a vocational counselor; and (e) there was no relationship between number of visits or number of professionals seen and return to work. CONCLUSION: The authors suggest a need for uniform standards in collection of outcome data to establish a basis for comparison of efficacy among programs. Recommendations include tracking comparison or control groups, grouping clients in terms of length of disability, computing success rate on the basis of number of clients who completed their program, using relevant subcategories when reporting return to work, and consistency of the postdischarge interval for follow-up.

Accidents, Occupational↗

Statement: occupational therapy services in work practice.

Occupational therapy practitioners focus on the individual's ability to participate in productive occupations throughout their life span. Through prevention, assessment, and intervention strategies, occupational therapy practitioners often collaborate with other members of the health care team and assist persons to optimize their ability to engage in purposeful occupation while facilitating a safe and successful entry into or return to work.

Accidents, Occupational↗