The increasing knowledge of the role of periconceptional folate in Victorian women of child-bearing age: follow-up of a randomised community intervention trial

OBJECTIVES

To determine the changes since 1996 in knowledge of folate for the prevention of neural tube defects (NTDs) among women of child-bearing age and measure the residual effect of an earlier consumer-directed information campaign.

DESIGN

A community, randomised trial with three matched pairs of geographically distinct local government areas in Victoria.

INTERVENTION

Printed information recommending folate intake to decrease the risk of NTDs was disseminated in 1997 to women of child-bearing age.

MAIN OUTCOME MEASURE

The proportion of women aware of the association between folate and spina bifida was established in 1996, 1997 and 2000 (approximately 200 respondents per local government area in each survey).

RESULTS

12.5% (adjusted for population sampling fraction) of 1,196 women interviewed in 1996, prior to the intervention, were aware of folate and NTDs. Independent surveys after the intervention in 1997 and again in 2000 showed that this had increased to 17.4% (n=1204) and 30.2% (n=1227) respectively. The intervention had a significant impact on folate awareness (a 4% difference in 1997 and a residual 3.3% in 2000, ORadj=1.24, 95% CI 1.19-1.37, p=0.007).

CONCLUSIONS AND IMPLICATIONS

There has been a continuing increased awareness of folate in women of child-bearing age since 1996. Within this setting, the provision of printed educational material in a brief intervention in 1997 has caused enduring increased awareness of the association between folate and NTDs. The need for ongoing health promotion action on folate remains.

Modelling the potential impact of population-wide periconceptional folate/multivitamin supplementation on multiple births

OBJECTIVE

To develop a model of the impact of population-wide periconceptional folate supplementation on neural tube defects and twin births.

DESIGN

A hypothetical cohort of 100,000 pregnancies > or =20 weeks, plus terminations of pregnancy after prenatal diagnosis before 20 weeks.

METHODS

Application of pooled data on the relative risks for neural tube defects and twins following periconceptional folate from meta-analysis of the randomised trials.

MAIN OUTCOME MEASURES

1. Pregnancies with a neural tube defect (i.e. terminations of pregnancy, perinatal deaths, and surviving infants); 2. twin births (i.e. preterm births, perinatal deaths, postneonatal deaths, birth defects, cerebral palsy); 3. numbers needed to treat.

RESULTS

The change in neural tube defects would be 75 fewer terminations (95% CI -47, -90), 30 fewer perinatal deaths (95% CI 18, -35), and 13 fewer surviving infants with a neural tube defect (95% CI -8, -16). The change in twinning would be an additional 572 twin confinements (95% CI -100, +1587), among whom there would be 63 very preterm twin confinements (95% CI -11, +174), 54 perinatal and postneonatal deaths (95% CI -9, +149), 48 surviving twins with a birth defect (95% CI -8, +133), and nine with cerebral palsy (95% CI -2, +26). The numbers needed to treat for the prevention of one pregnancy with a neural tube defect is 847, for the birth of one additional set of twins is 175, for the birth of one additional set of very preterm twins is 1587, and for the birth of an additional twin with any of the following outcomes (perinatal death, postneonatal death, survival with a birth defect, or survival with cerebral palsy) is 901.

CONCLUSIONS

Monitoring rates of neural tube defects and twinning is essential as supplementation or fortification with folate is implemented.

Canadian experiences in telehealth: equalizing access to quality care

The Canadian Conference "TExpo'98: Interactive Health" focused on four telehealth themes: community needs, Canadian experiences, industry perspectives, and access/security/interoperability issues. Health and socioeconomic needs have been the driving force behind telehealth initiatives; telelearning is one of the major Canadian initiatives. To encourage Canadian telehealth initiatives, the federal government is building a national health infrastructure. One element in this framework is concerned with empowering the public, strengthening health care services, and ensuring accountability. Technological advancements and innovative partnerships among health communities, government, users, professional bodies, and industry are critical to continued growth. Key issues including access, evaluation, implementation, privacy, confidentiality, security, and interoperability are of universal concern to participants. Research that examines the benefits and costs of telehealth is needed.

A descriptive study of UK cancer genetics services: an emerging clinical response to the new genetics

The objective was to describe NHS cancer genetic counselling services and compare UK regions. The study design was a cross-sectional study over 4 weeks and attendee survey. The setting was 22 of the 24 regional cancer genetics services in the UK NHS. Participants were individuals aged over 18 attending clinics at these services. Outcome measures were staff levels, referral rates, consultation rates, follow-up plans, waiting time. There were only 11 dedicated cancer geneticists across the 22 centres. Referrals were mainly concerned with breast (63%), bowel (18%) and ovarian (12%) cancers. Only 7% of referrals were for men and 3% were for individuals from ethnic minorities. Referral rates varied from 76 to 410 per million per annum across the regions. Median waiting time for an initial appointment was 19 weeks, ranging across regions from 4 to 53 weeks. Individuals at population-level genetic risk accounted for 27% of consultations (range 0%, 58%). Shortfalls in cancer genetics staff and in the provision of genetic testing and cancer surveillance have resulted in large regional variations in access to care. Initiatives to disseminate referral and management guidelines to cancer units and primary care should be adequately resourced so that clinical genetics teams can focus on the genetic testing and management of high-risk families.

Internodal specializations of myelinated axons in the central nervous system

We have examined the localization of contactin-associated protein (Caspr), the Shaker-type potassium channels, Kv1.1 and Kv1.2, their associated beta subunit, Kvbeta2, and Caspr2 in the myelinated fibers of the CNS. Caspr is localized to the paranodal axonal membrane, and Kv1.1, Kv1.2, Kvbeta2 and Caspr2 to the juxtaparanodal membrane. In addition to the paranodal staining, an internodal strand of Caspr staining apposes the inner mesaxon of the myelin sheath. Unlike myelinated axons in the peripheral nervous system, there was no internodal strand of Kv1.1, Kv1.2, Kvbeta2, or Caspr2. Thus, the organization of the nodal, paranodal, and juxtaparanodal axonal membrane is similar in the central and peripheral nervous systems, but the lack of Kv1.1/Kv1.2/Kvbeta2/Caspr2 internodal strands indicates that the oligodendrocyte myelin sheaths lack a trans molecular interaction with axons, an interaction that is present in Schwann cell myelin sheaths.

Technical standards and guidelines for fragile X: the first of a series of disease-specific supplements to the Standards and Guidelines for Clinical Genetics Laboratories of the American College of Medical Genetics. Quality Assurance Subcommittee of the Laboratory Practice Committee

Preface:

The Quality Assurance subcommittee of the ACMG Laboratory Practice committee has the mission of maintaining high technical standards for the performance and interpretation of genetic tests. In part, this is accomplished by the publication of the document “Standards and Guidelines for Clinical Genetics Laboratories,” which was published in its second edition in 1999 and is now maintained online (see www.faseb.org/genetics/acmg/index.html ). This subcommittee also reviews the outcome of national proficiency testing in the genetics area and may choose to focus on specific diseases or methodologies in response to those results. Accordingly, the subcommittee selected fragile X syndrome to be the first topic in a new series of supplemental sections, recognizing that it is one of the most frequently ordered genetic tests and that it has many alternative methods with different strengths and weaknesses. This document follows the outline format of the general Standards and Guidelines. It is designed to be a checklist for genetic testing professionals who are already familiar with the disease and the methods of analysis.

EGR2 mutations in inherited neuropathies dominant-negatively inhibit myelin gene expression

The identification of EGR2 mutations in patients with neuropathies and the phenotype Egr2/Krox20(-/-) have demonstrated that the Egr2 transcription factor is critical for peripheral nerve myelination. However, the mechanism by which these mutations cause disease remains unclear, as most patients present with disease in the heterozygous state, whereas Egr2(+/-) mice are phenotypically normal. To understand the effect of aberrant Egr2 activity on Schwann cell gene expression, we performed microarray expression profiling to identify genes regulated by Egr2 in Schwann cells. These include genes encoding myelin proteins and enzymes required for synthesis of normal myelin lipids. Using these newly identified targets, we have shown that neuropathy-associated EGR2 mutants dominant-negatively inhibit wild-type Egr2-mediated expression of essential myelin genes to levels sufficiently low to result in the abnormal myelination observed in these patients.

Use of Human Data for the Derivation of a Reference Dose for Chlorpyrifos

In 1998 a panel of experts met to discuss the data available on chlorpyrifos, both human and animal, and to determine the most appropriate endpoints to be used for the derivation of the reference dose (RfD). Since that time, additional data have become available on chlorpyrifos from an experimental study involving humans. Moreover, Food Quality Protection Act (FQPA) considerations need to be addressed, and the appropriate cholinesterase endpoint, whether plasma, red blood cell, peripheral nerve, or brain, has become highly debated. Therefore, Dow AgroSciences, one of the manufacturers of chlorpyrifos, convened a second panel of toxicology and medical experts on June 21, 1999, to consider the presently available scientific literature both published and unpublished on chlorpyrifos and to determine the acute and chronic toxicological RfDs for chlorpyrifos. Four questions were posed to this second panel of experts concerning the available data on chlorpyrifos. (1) Should the RfD for chlorpyrifos be based on acetylcholinesterase (AChE) inhibition or butyrylcholinesterase (BuChE) inhibition as an endpoint for adverse effect? (2) Should the RfDs for chlorpyrifos be based on the data set from three human studies, which are supported by animal data? (3) Should the FQPA safety factor be reduced to 1xbased on animal studies of pre- or postnatal toxicity? (4) If an RfD for chlorpyrifos were to be based on animal data, then is a 10-fold interspecies uncertainty factor necessary? The panel of experts concluded that: (1) inhibition of BuChE is not an adverse effect, and the RfD for chlorpyrifos should be based on AChE inhibition; (2) the RfD for chlorpyrifos should be based on the three available human studies, which are also supported by animal data; (3) the extra FQPA safety factor should be reduced to 1x, because chlorpyrifos shows no pre- or postnatal toxicity of concern at relevant human exposure conditions; and (4) the extra 10-fold safety factor for interspecies variation appears overly conservative because no differences in species sensitivity to chlorpyrifos is evident.

A CDK-independent function of mammalian Cks1: targeting of SCF(Skp2) to the CDK inhibitor p27Kip1

The Cks/Suc1 proteins associate with CDK/cyclin complexes, but their precise function(s) is not well defined. Here we demonstrate that Cks1 directs the ubiquitin-mediated proteolysis of the CDK-bound substrate p27Kip1 by the protein ubiquitin ligase (E3) SCF(Skp2). Cks1 associates with the F box protein Skp2 and is essential for recognition of the p27Kip1 substrate for ubiquitination in vivo and in vitro. Using purified recombinant proteins, we reconstituted p27Kip1 ubiquitination activity and show that it is dependent on Cks1. CKS1-/- mice are abnormally small, and cells derived from them proliferate poorly, particularly under limiting mitogen conditions, possibly due to elevated levels of p27Kip1.

Knowledge and attitudes of hospital staff to occupational exposure to bloodborne viruses

In order to assess awareness of occupational risk of exposure to bloodborne viruses a questionnaire was sent to 245 health care workers, representing a 10% sample of employees with patient contact in a large teaching hospital in Scotland, stratified by occupational group. One hundred and eight questionnaires (44%) were returned. Seventy per cent of respondents in laboratory and clinical areas described themselves as having sufficient knowledge for their own area of practice, but many gave incorrect answers or expressed uncertainty about the infectivity of HIV and hepatitis B and hepatitis C viruses. Ninety-four respondents were unaware that a regimen containing more than one antiretroviral drug is now recommended for post exposure prophylaxis of HIV infection, 37 thought they had been at risk of bloodborne viral infection and had contacted the occupational health department for advice, and 68 respondents disagreed with guidelines from the United Kingdom's General Medical Council on testing of patients for bloodborne viruses. The results indicate a need for educational initiatives for new and existing staff.

Understanding the experience of prophylactic bilateral mastectomy: a qualitative study of ten women

Prophylactic bilateral mastectomy represents a new and controversial cancer prevention strategy for women at high-risk of familial breast cancer, the psychosocial implications of which are yet to be fully explored. A qualitative methodology was therefore adopted to provide a discovery-orientated study of the perspectives of ten women who had undergone prophylactic mastectomy and the views of eight of their partners. Each participant was interviewed with the aim of exploring the personal experiences of surgery, factors associated with psychological adjustment and the impact on the family. Data were transcribed and systematically analysed using Grounded Theory. Themes emerging from participants' accounts formed seven significant categories that represented women's key experiences: (i) deciding; (ii) telling; (iii) experiencing surgery and recovering; (iv) maintaining womanliness; (v) processing the loss; and (vi) moving on. The importance of the social context in women's experience and difficulties of isolation/eliciting support were also highlighted: (vii) isolation and being supported. A core category of 'Suffering and countering multiple loss' considered central to women's experience, integrated the seven significant categories and provided further conceptualisation of women's experience. Implications for clinical practice are highlighted.

Neonatal tachyarrhythmias

CARDIAC ARRHYTHMIAS CAN BE found in the fetus and the neonate. Arrhythmias that are seen in the neonate include sinus bradycardia and tachycardia, premature atrial and ventricular contractions, supraventricular tachycardia, atrial flutter, ventricular arrhythmias, and heart block. Although infants with structural or functional anomalies can have arrhythmias, many arrhythmias result from noncardiac causes, such as hypoxemia and acidosis.1

An integrated environmental perfusion chamber and heating system for long-term, high resolution imaging of living cells

This communication presents the design and application of an integrated environmental perfusion chamber and stage heating blanket suitable for time-lapse video microscopy of living cells. The system consists of two independently regulated components: a perfusion chamber suitable for the maintenance of cell viability and the variable delivery of environmental factors, and a separate heating blanket to control the temperature of the microscope stage and limit thermal conduction from the perfusion chamber. Two contrasting experiments are presented to demonstrate the versatility of the system. One long-term sequence illustrates the behaviour of cells exposed to ceramic fibres. The other shows the shrinking response of cultured articular cartilage chondrons under dynamic hyper-osmotic conditions designed to simulate joint loading. The chamber is simple in design, economical to produce and permits long-term examination of dynamic cellular behaviour while satisfying the fundamental requirements for the maintenance of environmental factors that influence cell viability.

Proton magnetic resonance spectroscopy ((1)H-MRS) of the brain following high-dose methotrexate treatment for childhood cancer

BACKGROUND

To avoid the late sequelae associated with cranial radiation therapy in childhood, intermediate- or high-dose intravenous methotrexate (HDMTX) has found increasing application as a means of preventing the development of overt central nervous system disease in childhood acute leukaemia. However, acute and chronic neurotoxicity has been described following HDMTX therapy, and the long-term intellectual outcome in children treated in this way is inadequately documented. Proton magnetic resonance spectroscopy ((1)H-MRS) of the brain is a noninvasive, quantitative way of assessing aspects of cerebral metabolism, which has not previously been applied to the study of children undergoing central nervous system directed therapy.

PROCEDURE

To evaluate the potential role of (1)H-MRS in the investigation of related neurotoxicity, 11 children who had received HDMTX (cumulative dose 6-96 g/m(2)) underwent localised (1)H-MRS, magnetic resonance imaging. Neuropsychological assessments were performed on the children who had more than 1 year of follow-up time since last methotrexate treatment. Control (1)H-MRS studies on 11 adult and 6 young volunteers were undertaken. Eight patients had spectra of adequate quality. Comparisons between (1)H-MRS metabolite ratios and normal controls were made.

RESULTS

Patients had a low choline/water ratio compared to controls (P < 0.01). No differences between patient and control NAA/water, Cr/water, Naa/Cr, and Cho/Cr ratios were seen. Overall, 3 patients had abnormal white matter changes on MRI. The mean IQ of the patients (104.1) was in the normal range.

CONCLUSIONS

It is postulated that choline depletion in the brains of these patients may reflect subclinical disturbances of myelin metabolism as a result of methotrexate therapy and may represent a possible avenue of treatment in patients with clinical chronic methotrexate-related neurotoxicity.

Hemoglobin adducts from acrylonitrile and ethylene oxide in cigarette smokers: effects of glutathione S-transferase T1-null and M1-null genotypes

Acrylonitrile (ACN) is used to manufacture plastics and fibers. It is carcinogenic in rats and is found in cigarette smoke. Ethylene oxide (EO) is a metabolite of ethylene, also found in cigarette smoke, and is carcinogenic in rodents. Both ACN and EO undergo conjugation with glutathione. The objectives of this study were to examine the relationship between cigarette smoking and hemoglobin adducts derived from ACN and EO and to investigate whether null genotypes for glutathione transferase (GSTM1 and GSTT1) alter the internal dose of these agents. The hemoglobin adducts N-(2-cyanoethyl)valine (CEVal), which is formed from ACN, and N-(2-hydroxyethyl)valine (HEVal), which is formed from EO, and GST genotypes were determined in blood samples obtained from 16 nonsmokers and 32 smokers (one to two packs/day). Smoking information was obtained by questionnaire, and plasma cotinine levels were determined by immunoassay. Glutathione transferase null genotypes (GSTM1 and GSTT1) were determined by PCR. Both CEVal and HEVal levels increased with increased cigarette smoking dose (both self-reported and cotinine-based). CEVal and HEVal levels were also correlated. GSTM1 and GSTT1 genotypes had little effect on CEVal concentrations. GSTM1 null genotypes had no significant impact on HEVal. However, HEVal levels were significantly elevated in GSTT1-null individuals when normalized to smoking status or cotinine levels. The ratio of HEVal:CEVal was also elevated in GSTT1-null smokers (1.50 +/- 0.57 versus 0.88 +/- 0.24; P = 0.0002). The lack of a functional GSTT1 is estimated to increase the internal dose of EO derived from cigarette smoke by 50-70%.

Development of the Royal Marsden Hospital paediatric oncology quality of life questionnaire

Our objective was to develop a health-related quality of life measure for use in pediatric oncology. The development process followed the EORTC Quality of Life Study Group (QLSG) guidelines but utilized a parental proxy rating methodology developed within the framework of the EORTC QLSG. Data are reported on the preliminary stages of development, which include interviews in the target population, specialist review of questionnaire content and initial results on the psychometric structure of the measure. The questionnaire has been translated from English to Swedish and Dutch and is available for international field testing. Suggestions for further development of the new measure are described, including the need for parallel forms for use with children and adolescents as well as the parental proxy rating form described here.

Inhibition of cytokinesis by asbestos and synthetic fibres

Using high-resolution timelapse microscopy, we have followed individual phagocytized fibres through the later stages of division in MeT-5A human mesothelial cells and LLC-MK(2)monkey epithelial cells. The fibres used were crocidolite and chrysotile asbestos, fibrous glass (MMVF), and refractory ceramic fibres (RCF). Long fibres (15-80 microm) trapped within the cleavage furrow can partially or completely block cytokinesis. Cells proceed in one of three ways: (1) eventual completion of cytokinesis; (2) incomplete cytokinesis, resulting in two cells joined by a fibre-containing intercellular channel; or (3) failure of cytokinesis, resulting in a binucleate or trinucleate cell. Two factors associated with fibre-induced bi/trinucleation are: (1) an initial association between the fibre and the forming daughter nuclei, which is sometimes lost over time, and (2) disintegration of the midbody. The studies suggest that delay of cytokinesis by interzonal fibres can result in bi/trinucleation through the loss of midbody/intercellular bridge proteins that are required for completion of cytokinesis.