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A Summers

Publications and source records attributed to A Summers.

At least 19 recordsLinked to original sources
PubMed2003

Predictive, pre-natal and diagnostic genetic testing for Huntington's disease: the experience in Canada from 1987 to 2000.

Predictive and pre-natal testing for Huntington's Disease (HD) has been available since 1987. Initially this was offered by linkage analysis, which was surpassed by the advent of the direct mutation test for HD in 1993. Direct mutation analysis provided an accurate test that not only enhanced predictive and pre-natal testing, but also permitted the diagnostic testing of symptomatic individuals. The objective of this study was to investigate the uptake, utilization, and outcome of predictive, pre-natal and diagnostic testing in Canada from 1987 to April 1, 2000. A retrospective design was used; all Canadian medical genetics centres and their affiliated laboratories offering genetic testing for HD were invited to participate. A total of 15 of 22 centres (68.2%), currently offering or ever having offered genetic testing for HD, responded, providing data on test results, demographics, and clinical history. A total of 1061 predictive tests, 15 pre-natal tests, and 626 diagnostic tests were performed. The uptake for predictive testing was approximately 18% of the estimated at-risk Canadian population, ranging from 12.5% in the Maritimes to 20.7% in British Columbia. There appears to have been a decline in the rate of testing in recent years. Of the predictive tests, 45.0% of individuals were found to have an increased risk, and a preponderance of females (60.2%) sought testing. A greater proportion of those at < or = 25% risk sought predictive testing once direct CAG mutation analysis had become available (10.9% after mutation analysis vs 4.7% before mutation analysis, p = 0.0077). Very few pre-natal tests were requested. Of the 15 pre-natal tests, 12 had an increased risk, resulting in termination of pregnancy in all but one. Diagnostic testing identified 68.5% of individuals to be positive by mutation analysis, while 31.5% of those with HD-like symptoms were not found to have the HD mutation. The positive diagnostic tests included 24.5% of individuals with no known prior family history of HD.

Adolescent↗
PubMed2002

The influence of applicator angle on dosimetry in vaginal vault brachytherapy.

In vaginal vault brachytherapy, the critical normal tissues are bladder and rectum; doses to these tissues may be affected by the position of a single line applicator placed in the vagina. Dosimetry with the applicator lying at its "natural" angle in the vagina with the patient in the lithotomy position has been compared with the applicator held horizontal as defined by a spirit level in 30 consecutive patients. A mean change in angle of 19.7 degrees was found. This resulted in a mean decrease in ICRU (International Commission of Radiation Units and Measurements) rectal point dose when the applicator is horizontal of 12.9%, equivalent to a mean absolute dose reduction of 1.3 Gy for a prescription dose of 5.5 Gy at 5 mm depth. An increase in mean dose to the ICRU bladder point when the applicator is horizontal of 13.3%, equivalent to an absolute mean dose increase of 0.5 Gy per fraction for the same prescription dose, was also found. On the basis of these findings, it is recommended that vaginal vault brachytherapy is performed with a single line source held in the "corrected" horizontal position to reduce bowel dose as this is the most sensitive critical normal tissue.

Brachytherapy↗
PubMed2000

Lack of germline CDK6 mutations in familial melanoma.

Germline mutations in genes encoding several components of the retinoblastoma pathway have been linked with inherited predisposition to melanoma. Most commonly, such mutations involve CDKN2A, a cyclin-dependent kinase inhibitor of two kinases, CDK4 and CDK6, which phosphorylate the retinoblastoma protein (pRB) and thereby promote passage through the G1/S cell-cycle restriction point. Less frequently, germline mutations in the CDK4 gene have also been linked with an increased risk of melanoma. Despite the sequence and functional homology between CDK4 and CDK6, the role of germline mutations in CDK6 in melanoma predisposition is unknown. We detected no CDK6 mutations within the p16 (CDKN2A) binding domain in index cases from 60 melanoma-prone kindreds that lacked germline mutations in the coding regions of either CDKN2A or within the entire CDK4 coding region. We conclude that germline mutations in CDK6 do not make a significant contribution to melanoma predisposition.

Amino Acid Sequence↗
PubMed2000

Transportation of maternal serum specimens for screening for chromosomal aneuploidies: effect of seasonal variations, distance, and freezing on the stability of the biological markers.

OBJECTIVES: We studied the stability of maternal serum markers for screening for Down syndrome [alpha-fetoprotein (AFP), unconjugated estriol (uE3), total human chorionic gonadotropin (hCG), and free beta-human chorionic gonadotropin] following transportation. DESIGN AND METHODS: For each gestational week between 14 and 18 weeks, we collected about 50 samples for each possible combination of three potential sources of variation during transportation: season (winter/summer), sample frozen/fresh (prior to analysis) and origin (local or referred in) for a total of 1845 specimens. Commercial assays were used (IMx, Abbott for AFP and total hCG; AutoDelfia and Wallac for free beta-hCG and AFP; and radioimmunoassay Ortho-Clinical Diagnostics, for uE3). RESULTS: Results of both total and free beta-hCG were significantly higher when samples were collected during summer and when they were sent to the laboratory from extramural blood drawing sites (multifactorial ANOVA, p < 0. 007). CONCLUSION: We conclude that both total and free beta-hCG can be adversely affected during transportation. The resulting higher concentrations of these markers may increase the false positive rate of prenatal screening programs for aneuploidies.

Biomarkers↗
PubMed2000

A different start: midwifery in South Australia 1836-1920.

It is the popular belief of many midwives and nurses in Australia that midwives of the nineteenth and early twentieth century in this country practiced completely independently of medicine, resorting to medical assistance only if the labor and delivery did not progress normally. There is also the opinion that only affluent childbirthing women had a medical man in attendance at the delivery and poorer women had a midwife. Indeed, much of the Australian historical literature supports these notions. However, evidence suggests that in South Australia this was not the case and that generally midwives practiced in collaboration with medical men. Apart from some exceptions, both midwives and medical men attended the deliveries of most childbirthing women from all strata of society. This paper will explore the provision of midwifery care in the early days of settlement in South Australia and show how the relationship between the community midwife and the general practitioner developed. In doing so, this paper will establish that the normal place of delivery in nineteenth-century South Australia was in the home with both a doctor and midwife in attendance as part of normal community life.

Australia↗
PubMed1999

Mutation of the CDKN2A 5' UTR creates an aberrant initiation codon and predisposes to melanoma.

Approximately 8-12% of melanoma is inherited in an autosomal dominant fashion with variable penetrance. A chromosome 9p21 locus has been linked to this disease in 50-80% of affected families. CDKN2A (also known as P16, INK4, p16INK4A and MTS1) is allelic to this locus and encodes a cdk4/cdk6 kinase inhibitor that constrains cells from progressing through the G1 restriction point. Although germline CDKN2A coding mutations cosegregate with melanoma in 25-60% of families predisposed to the disease, there remains a number of mutation-negative families that demonstrate linkage of inherited melanoma to 9p21 markers. We show here that a subset of these kindreds possess a G-->T transversion at base -34 of CDKN2A, designated G-34T. This mutation gives rise to a novel AUG translation initiation codon that decreases translation from the wild-type AUG. The G-34T mutation is not seen in controls, segregates with melanoma in families and, on the basis of haplotyping studies, probably arose from a common founder in the United Kingdom. Characterization of this and other CDKN2A non-coding mutations should have an impact on current efforts to identify susceptible melanoma-prone families and individuals.

5' Untranslated Regions↗
PubMed1998

Psychological outcomes following maternal serum screening: a cohort study.

BACKGROUND: Maternal serum screening is used to assist in the prenatal detection of congenital anomalies. Its use is controversial, and one concern that has been expressed is its psychological effects on women. The authors examined whether this test leads to an increase in anxiety and depression among women who have a false-positive result as compared with those who have a true-negative result or do not undergo testing. METHODS: A prospective cohort study with baseline assessment at 15 to 18 weeks' gestation and follow-up at 24 weeks' gestation was conducted. Pregnant women at 8 geographically diverse sites across Ontario were recruited. The main outcome measures were the state portion of the State--Trait Anxiety Inventory and the Center for Epidemiologic Studies Depression Scale. RESULTS: Of the 2418 potential subjects 2020 (83.5%) were enrolled and eligible; 1741 (86.2%) completed the follow-up. A total of 1177 women (67.6%) underwent maternal serum screening. No overall adverse psychological effects as a result of testing were found at 24 weeks' gestation. Women with a false-positive result had a mean increase in anxiety score of 1.6 (95% confidence interval [CI] -1.7 to 4.9), whereas women with a true-negative result had a mean decrease of 1.1 (95% CI -1.8 to -0.3) and those not tested had a mean decrease of 0.4 (95% CI -1.3 to 0.5). The mean depression score increased by 0.5 (95% CI -0.9 to 2.0) in the false-positive group, was unchanged (95% CI -0.3 to 0.4) in the true-negative group and increased by 0.2 (95% CI -1.7 to 1.2) in the not tested group. Of the women who underwent testing, 87 (7.6%) were unsure of their result at the time of follow-up. INTERPRETATION: The results suggest that maternal screening in Ontario is not causing serious psychological harm to women. Communication regarding test results could be improved, since a substantial proportion of women were unsure of their test result.

Adult↗
PubMed1998

The lost voice of midwifery.

The proposed review and amendments to the Nurses' Act in South Australia has caused intense debate in this state especially between nurses and midwives. On the one hand midwives claim that the new changes will affect their ability to deliver optimum care to the childbirthing woman and so affect their role as midwife. While on the other hand nurses counter claim that the proposed changes to the Act will not make any difference to midwifery care and cannot understand what all the fuss is about. Yet midwifery has never sat comfortably under the umbrella of nursing and this debate is not new. This paper takes a historical look at the professionalisation of nursing prior to the implementation of the original Nurses' Registration Act of South Australia in 1920. It explores the implications of this for the midwife of the time, highlighting the unresolved differences between these two professions that have contributed to the debate of today.

Female↗
PubMed1998

Role of the cyclin-dependent kinase inhibitor CDKN2A in familial melanoma.

BACKGROUND: Approximately 8 to 12% of melanoma appears to be inherited in an autosomal dominant form. Although most early stage melanomas can be treated successfully by simple surgical excision, patients with advanced disease are rarely cured even with aggressive chemotherapy and/or immunotherapy. OBJECTIVE: There is now compelling evidence that germline mutations of the CDKN2A gene on chromosome 9p21 predispose to melanoma in a subset of melanoma-prone families. In this article the evidence for the role of CDKN2A in the genesis of familial melanoma is reviewed and the implications of genetic testing in families with this disease are discussed. CONCLUSION: The identification and subsequent surveillance of unaffected individuals who have a genetic predisposition to melanoma may lead to the detection of early (curable) melanomas and to a reduction in mortality.

Cell Cycle↗
PubMed1997

Case-control study of stroke and the quality of hypertension control in north west England.

OBJECTIVE: To examine the risk of stroke in relation to quality of hypertension control in routine general practice across an entire health district. DESIGN: Population based matched case-control study. SETTING: East Lancashire Health District with a participating population of 388,821 aged < or = 80. SUBJECTS: Cases were patients under 80 with their first stroke identified from a population based stroke register between 1 July 1994 and 30 June 1995. For each case two controls matched with the case for age and sex were selected from the same practice register. Hypertension was defined as systolic blood pressure > or = 160 mm Hg or diastolic blood pressure > or = 95 mm Hg, or both, on at least two occasions within any three month period or any history of treatment with antihypertensive drugs. MAIN OUTCOME MEASURES: Prevalence of hypertension and quality of control of hypertension assessed by using the mean blood pressure recorded before stroke) and odds ratios of stroke (derived from conditional logistic regression). RESULTS: Records of 267 cases and 534 controls were examined; 61% and 42% of these subjects respectively were hypertensive. Compared with non-hypertensive subjects hypertensive patients receiving treatment whose average pre-event systolic blood pressure was controlled to < 140 mm Hg had an adjusted odds ratio for stroke of 1.3 (95% confidence interval 0.6 to 2.7). Those fairly well controlled (140-149 mm Hg), moderately controlled (150-159 mm Hg), or poorly controlled (> or = 160 mm Hg) or untreated had progressively raised odds ratios of 1.6, 2.2, 3.2, and 3.5 respectively. Results for diastolic pressure were similar; both were independent of initial pressures before treatment. Around 21% of strokes were thus attributable to inadequate control with treatment, or 46 first events yearly per 100,000 population aged 40-79. CONCLUSIONS: Risk of stroke was clearly related to quality of control of blood pressure with treatment. In routine practice consistent control of blood pressure to below 150/90 mm Hg seems to be required for optimal stroke prevention.

Adult↗
PubMed1997

Written patient information about triple-marker screening: a randomized, controlled trial.

OBJECTIVE: To investigate to what extent a newly revised educational pamphlet on triple-marker screening improves patient knowledge and to identify subgroups of women who may not benefit from these materials. METHODS: Women in six geographically and demographically diverse Ontario sites were allocated randomly to receive the pamphlet on triple-marker screening or a similar-appearing educational pamphlet on daily activities during pregnancy. The primary outcome measure was the Maternal Serum Screening Knowledge Questionnaire, a previously validated 14-item scale. RESULTS: Baseline demographic, obstetric, and medical factors were comparable in the intervention and control groups, as were measures of previous exposure to triple-marker screening. Knowledge scores were significantly higher among the 133 women receiving the intervention pamphlet than among 64 women who received the control pamphlet (0.89 versus 0.52 on a scale from -2 to +2, P < .001). Subgroups not benefiting from the pamphlet on triple-marker screening were women age 25 and younger and those not speaking English at home. Those who had completed university or postgraduate education had high levels of knowledge with and without the pamphlet. CONCLUSION: Written patient information can contribute in an important way to patient knowledge about triple-marker screening. Providers of antenatal care should be made aware of the value of written patient information as well as the limitations for some subgroups of women. These subgroups are likely to require additional educational materials and resources. It would be appropriate to make these materials available to the general public and pregnant women in their physicians' offices.

Adult↗
PubMed1997

Sairey Gamp: generating fact from fiction.

Australian midwives today are generally employed by maternity hospitals as obstetric or maternity nurses and specialize in only one area of the childbirthing process, under the umbrella of medicine. This is quite different to the provision of midwifery care in the nineteenth and early twentieth centuries in Australia, when childbirthing took place within a home setting, with a community midwife in attendance under the umbrella of the household. Australian midwives are now attempting to regain some of the autonomy that they believe was possessed by midwives of the past by being professionally accredited to operate as independent midwives. The de-institutionalization of childbirthing cannot simply come about by giving midwives accreditation to operate as autonomous practitioners, as the forces that led society to institutionalize childbirthing practices, as well as the avenues for change, are complex. This paper examines one of the forces behind that change: the denigration of the image of the community midwife by the medical and nursing professions, through the character of Sairey Gamp created by Charles Dickens. By examining the historical terrain and the historical influences that led to the demise of the community midwife, we can provide answers for debate on the present status of the midwife.

Australia↗
PubMed1997

A community based stroke register in a high risk area for stroke in north west England.

STUDY OBJECTIVE: To develop a community based stroke register to assess the magnitude of the problem of stroke in an entire health district in a high risk area for stroke. DESIGN: Community based stroke register from general practice data. SETTING: East Lancashire Health Authority with a 1995 population of 534,287. PATIENTS: The stroke register was developed and maintained for one calendar year in East Lancashire between 1 July 1994 and 30 June 1995. Efforts were made to include all patients who had a stroke during this period from participating general practices, using several sources of referral. MAIN RESULTS: Of the district's 118 general practices, 93 (79%) participated fully, covering a population of 405,272. A total of 932 strokes, including 642 first ever cases, were cross checked and confirmed, with only 50% from any single source, mainly the practices. The total stroke incidence rate was 1.60 per 1000 per year, adjusted for the England and Wales 1991 census population. The rate increased considerably with age from 0.88/1000 for ages 50-54 to 20.56/1000 for ages 85-89 years. From 50-74 years, the age specific incidence was higher in men, but overall it was higher in women (1.87; 95% confidence interval 1.67, 2.04 per 1000) than in men (1.31; 1.15, 1.47 per 1000), and slightly lower than in Oxford a decade earlier. The rate also varied in different localities, with higher rates in the central towns of Hyndburn (2.05/ 1000), Blackburn (1.63/1000), and Burnley (1.80/1000) and lowest values in rural areas (1.18/1000 in Pendle). Case fatality from stroke at 28 days was 34% and the hospital admission rate was high at 70%. CONCLUSIONS: The multiple source registration method is required for a stroke register. Stroke incidence in this area was still high and there was considerable variation across the district. Case fatality rates were similar to those in previous studies.

Adult↗
PubMed1996

Evaluating patient's knowledge of maternal serum screening.

The objective was to describe the development, characteristics, and initial use of an instrument for assessing knowledge about maternal serum screening (MSS). Items for a knowledge scale were selected based on a review of educational materials, the literature, and expert opinion. Items were pre-tested for comprehensibility and ambiguity in a convenience sample. After extensive pre-testing and pilot testing a 14-item scale, the Maternal Serum Screening Knowledge Questionnaire (MSSKQ) was developed. It was administered to 1084 women attending a maternal registration clinic. The overall knowledge score was compared across socio-demographic groups, and by sources of information about MSS. Mean MSSKQ scores increased with age, education, and family income, and among those reporting having an opportunity to discuss MSS and receiving written material. The MSSKQ is a reliable instrument with good content and construct validity. This tool should be valuable in assessing knowledge and level of informed consent in women receiving MSS and in evaluating the implementation of MSS programmes.

Adult↗
PubMed1996

Local voices: evolving a realistic strategy on public consultation.

The publication of Local Voices in 1992 challenged Health Authorities to develop an effective system for their public consultation activities compatible with the requirements of the internal market.1 The general rhetoric was persuasive, but it was less clear how, and to what extent, Local Voices work would influence Health Authority decisions. Serious questions about the nature, purpose and impact of Local Voices were raised within a year of publication.2 This paper re-examines the issues and discusses some of the benefits and limitations of public consultation exercises, using as illustrations two projects carried out in East Lancashire, one on adult mental illness3 and the other on maternity services.4 Particular consideration is given to the precise impact on commissioning of public consultation exercises, and the dilemmas and tensions which emerge as the commissioners consider different findings from different methodologies and different population subgroups. The final section of the article summarises the lessons learnt and sketches out a more systematic and critical approach to public consultation.

Adult↗
PubMed1996

Prevalence of multiple sclerosis in Rochdale.

The prevalence of multiple sclerosis in the Rochdale Metropolitan Borough in the north east of Greater Manchester has been established. Case ascertainment was partly prospective via a neurological register from 1979 and by contact with general practitioners, therapists, and social services. On prevalence day, 1 January 1989, 254 patients with multiple sclerosis were living in Rochdale. The overall prevalence was 122/100,000 population and 96/100,000 population for probable cases only. The peak rate for women aged 35 to 44 years was 437/100,000 population and for men aged 45 to 54 years 221/100,000. Familial multiple sclerosis was present in 10.8% of families. In this, the first study in north west England, the prevalence of multiple sclerosis in Rochdale is similar to that in southern England and Wales but lower than that in Scotland.

Adult↗