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S Adam

Publications and source records attributed to S Adam.

At least 73 records · Page 4Linked to original sources
PubMed1993

Molecular analysis of new mutations for Huntington's disease: intermediate alleles and sex of origin effects.

Huntington's disease (HD) is associated with expansion of a CAG repeat in a novel gene. We have assessed 21 sporadic cases of HD to investigate sequential events underlying HD. We show the existence of an intermediate allele (IA) in parental alleles of 30-38 CAG repeats in the HD gene which is greater than usually seen in the general population but below the range seen in patients with HD. These IAs are meiotically unstable and in the sporadic cases, expand to the full mutation associated with the phenotype of HD. This expansion has been shown to occur only during transmission through the male germline and is associated with advanced paternal age. These findings suggest that new mutations for HD are more frequent than prior estimates and indicate a previously unrecognized risk of inheriting HD to siblings of sporadic cases of HD and their children.

Adult↗
PubMed1993

Five year study of prenatal testing for Huntington's disease: demand, attitudes, and psychological assessment.

Adult predictive and prenatal testing programmes for Huntington's disease (HD) in Canada have been available since 1986. However, the demand for prenatal testing and the reasons why some people choose not to have the prenatal test for this late onset disorder have not been well documented. In addition, the knowledge and attitudes of adult predictive testing candidates and their partners about prenatal testing are not well known nor are the psychological effects of prenatal testing well understood. As of September 1991, 425 subjects had entered the Canadian Collaborative Study of Predictive Testing and, of these, 47 subjects or their partners had become pregnant. Of this group, 14 (30%) couples requested prenatal testing, 24 (51%) couples did not want prenatal testing, and nine (19%) at risk subjects had already received a decreased risk through adult predictive testing and, therefore, were not eligible for the prenatal test. Of the 14 couples who initially requested prenatal testing, seven withdrew. Thus, demand for the prenatal test by eligible candidates was 7/38 or 18%, which is much lower than the 32 to 65% expected based on early survey data. The most frequently cited reason for declining prenatal testing was the hope that a cure would be found in time for their children. While the majority of adult predictive testing candidates (71%) in our study had accurate information about definitive prenatal testing, many (63%) did not have a correct understanding of exclusion prenatal testing. Although no serious adverse events such as suicide planning or admission to psychiatric hospital have occurred, a particular need for careful counselling was identified for those at risk candidates and their partners who have one prenatal test and feel compelled to use the test again in future pregnancies. Even though prenatal testing for HD is not requested as often originally expected, it still remains a desired option for some at risk persons and their partners.

Adult↗
PubMed1992

The psychological consequences of predictive testing for Huntington's disease. Canadian Collaborative Study of Predictive Testing.

BACKGROUND: Advances in molecular genetics have led to the development of tests that can predict the risk of inheriting the genes for several adult-onset diseases. However, the psychological consequences of such testing are not well understood. METHODS: The 135 participants in the Canadian program of genetic testing to predict the risk of Huntington's disease were followed prospectively in three groups according to their test results: the increased-risk group (37 participants), the decreased-risk group (58 participants), and the group with no change in risk (the no-change group) (40 participants). All the participants received counseling before and after testing. Standard measures of psychological distress (the General Severity Index of the Symptom Check List 90-R), depression (the Beck Depression Inventory), and well-being (the General Well-Being Scale) were administered before genetic testing and again at intervals of 7 to 10 days, 6 months, and 12 months after the participants received their test results. RESULTS: At each follow-up assessment, the decreased-risk group had lower scores for distress than before testing (P < 0.001). The increased-risk group showed no significant change from base line on any follow-up measure, but over the year of study there were small linear declines (P < 0.023) for distress and depression. The no-change group had scores lower than at base line on the index of general well-being at each follow-up (P < or = 0.045). At the 12-month follow-up, both the increased-risk group and the decreased-risk group had lower scores for depression and higher scores for well-being than the no-change group (P < or = 0.049). CONCLUSIONS: Predictive testing for Huntington's disease has potential benefits for the psychological health of persons who receive results that indicate either an increase or a decrease in the risk of inheriting the gene for the disease.

Adult↗
PubMed1992

Predictive testing for Huntington disease in Canada: the experience of those receiving an increased risk.

Predictive testing for Huntington disease (HD) has been offered in some parts of Canada for nearly 5 years. Candidates who were expected to have a significant likelihood for psychological problems were those who received an increased risk for developing HD. Sixty-six persons have now received such an increased risk result. In this manuscript we describe in detail the experience of 4 such persons who were chosen to illustrate recurrent and common themes which have emerged during counselling, and to highlight the strategies of coping with this information. Themes include difficulties communicating about HD, defensive postures adopted in preparing for testing, ramifications of testing for the whole family, and the impact of being at high risk on the candidates' perception of the future. One candidate has had testing postponed due to active suicidal risk. Only a few candidates have expressed regret at taking the test and no person receiving an increased risk result has made a suicide attempt or required hospitalization. After receiving results, symptoms of depression and anxiety are most common in the first 2 months, but over 1 year, candidates, in general, have less depression but live with a heightened perception of the present. The potential risk of premature diagnosis of HD in an individual with an increased risk results is highlighted. The significant ramifications of testing for the relative are shown. The importance of communication as a means of establishing a social support network, as well as the hazards of open communication, are discussed. Longitudinal evaluation will provide much needed data on the long-term effects of living at increased risk for HD.

Adult↗
PubMed1992

Predictive testing for Huntington disease in Canada: adverse effects and unexpected results in those receiving a decreased risk.

By January 1, 1991, a total of 388 persons had enrolled in the Canadian collaborative study of predictive testing for Huntington disease (HD). Of these participants, 105 persons have been given a decreased risk result. Contrary to expectations, approximately 10% of persons with a decreased risk result have had psychological difficulties coping with their new status. Here, we describe the individual responses of 6 such persons and experimental themes emerging after following these persons for up to 2 years. Individuals who are more likely to suffer an adverse reaction to a decreased risk result include those persons who have made irreversible decisions based on the belief they would develop HD or those who had unrealistic overoptimistic expectations of the positive effects of a decreased risk result. In contrast to those receiving an increased risk result, the most vulnerable time for persons receiving a decreased risk result is between 2 and 12 months after learning the outcome. The need for assessment and counselling of participants in predictive testing programs, even when there is a decreased risk result, is emphasized.

Adult↗
PubMed1992

Breaking into prisons.

Explore the source record for details and available documents.

Health Services Administration↗
PubMed1992

Humoral responses to type I collagen after surgical curettage procedures employing bovine collagen implants.

Freeze-dried bovine type I collagen was implanted into periodontally diseased sites of 11 patients in an effort to repair the affected site. Peripheral blood samples taken at 0, 6 and 12 wk were assayed for antibody to human and bovine collagen using an enzyme-linked immunosorbent assay and compared with samples from 9 control subjects. Antibody levels to both human and bovine collagen, which were present at significantly higher levels in the patients at 0 wk than in the control subjects (P less than 0.01 for human and bovine), were significantly lower at 6 wk than at zero time (P less than 0.05 and P less than 0.01 for human and bovine collagens, respectively). At 12 wk post-implantation, the antibody level to human collagen still remained significantly lower (P less than 0.05) than zero time levels but not in respect of the antibody to bovine collagen.

Adult↗
PubMed1992

How should Fitts' Law be applied to human-computer interaction?

The paper challenges the notion that any Fitts' Law model can be applied generally to human-computer interaction, and proposes instead that applying Fitts' Law requires knowledge of the users' sequence of movements, direction of movement, and typical movement amplitudes as well as target sizes. Two experiments examined a text selection task with sequences of controlled movements (point-click and point-drag). For the point-click sequence, a Fitts' Law model that used the diagonal across the text object in the direction of pointing (rather than the horizontal extent of the text object) as the target size provided the best fit for the pointing time data, whereas for the point-drag sequence, a Fitts' Law model that used the vertical size of the text object as the target size gave the best fit. Dragging times were fitted well by Fitts' Law models that used either the vertical or horizontal size of the terminal character in the text object. Additional results of note were that pointing in the point-click sequence was consistently faster than in the point-drag sequence, and that pointing in either sequence was consistently faster than dragging. The discussion centres around the need to define task characteristics before applying Fitts' Law to an interface design or analysis, analyses of pointing and of dragging, and implications for interface design.

Data Display↗
PubMed1991

A new class of potent antiproliferative glycolipids.

The synthesis and biological activities of a new class of antiproliferative glycolipids with an unexpected broad spectrum of activity, including a human multidrug resistant cell line, are described. Chemically these compounds are glycolipids derived from N-acetyl-D-glucosamine and glycyrrhetinic acid (beta-aglycone). Peptidation of the glucoacids allyl 3 beta-[[2-acetamido-3-O-[(R)-1-carboxyethyl]- 2-deoxy-4,6-O-isopropylidene-beta-D-glucopyranosyl]oxy]-11-oxo-12- oleanen-30-oate and (R,S)-2-methoxy-3-(octadecyloxy)propyl-2-acetamido-3-O-[(R)-1-carb oxyethyl]- 2-deoxy-4,6-O-isopropylidene-beta-D-glucopyranoside was successfully achieved after activation with O-benzotriazolyl-N,N,N',N' -tetramethyluronium hexafluorophosphate.

Acetylglucosamine↗
PubMed1991

Linkage disequilibrium and modification of risk for Huntington disease.

The major limitation in performing predictive testing for Huntington disease (HD) is the unavailability of DNA from crucial family members. In our program approximately 20% (36/183) of persons have been excluded from predictive testing because of this reason. The major aim of this study was to examine whether data derived from linkage disequilibrium could modify risk analysis for persons at risk for HD. As a first step, we assessed whether the previously reported linkage disequilibrium between alleles recognized by probe pBS674E-D at locus D4S95 remained significant in a much larger data set. A total of 1,150 chromosomes from 622 individuals--200 affected and 422 unaffected--from 118 families were assessed. Significant haplotype association was detected with AccI and MboI RFLPs at the locus D4S95, with all the families (P = .00003), as well as for a subset from the United Kingdom (P = .0037). Data derived from linkage disequilibrium studies using D4S95 modifies the risk for HD, especially in persons of U.K. descent. Utilization of this approach for risk modification of HD awaits both validation of these data and additional information concerning ethnic-specific alleles at the D4S95 locus.

Adult↗
PubMed1989

Community attitudes to cystic fibrosis carrier testing in England: a pilot study.

Inexpensive and accurate carrier testing for cystic fibrosis (CF) will be possible in the near future. There are no existing studies on the attitudes of English persons in the community to carrier testing for CF or any other recessive disorder. We have conducted a trial study of 166 persons at two schools, two doctors' surgeries, and a family planning clinic. Only a minority had clear pre-existing knowledge of cystic fibrosis and its genetic nature. However, over 80 per cent of those questioned expressed interest in knowing their carrier status. Although it is well known that uptake can only be assessed when a service is in place, and while further studies are required to confirm that testing will be of interest to couples of reproductive age with no previous knowledge of CF, the data strongly suggest that there will be interest in community-wide testing for CF carrier status when such a test becomes available in the United Kingdom.

Attitude to Health↗