A preliminary study of cerebral blood flow, aging and dementia in people with Down syndrome

BACKGROUND

People with Down syndrome (DS) develop Alzheimer's disease (AD) at an earlier age of onset than those with sporadic AD. AD neuropathology is typically present in DS by 40 years of age with an onset of dementia approximately 10 years later. This early onset is due to the overexpression of amyloid precursor protein from the third copy of chromosome 21. Cerebrovascular neuropathology is thought to contribute in 40-60% of cases sporadic AD. However, the vascular contribution to dementia in people with DS has been relatively unexplored. We hypothesised that vascular perfusion is compromised in older adults with DS relative to younger individuals and is further exacerbated in those with dementia.

METHOD

Cerebral blood flow (CBF) was measured using pulsed arterial spin labelling in 35 cognitively characterised adults with DS (26-65 years). DS participants were also compared with 15 control subjects without DS or dementia (26-65 years). Linear regression evaluated the difference in CBF across groups and diagnosis along with assessing the association between CBF and cognitive measures within the DS cohort.

RESULTS

Cerebral blood flow was significantly lower among DS participants with probable AD compared with controls (P = 0.02) and DS participants with no dementia (P = 0.01). Within the DS cohort, CBF was significantly associated with the Severe Impairment Battery (SIB) measure and the Dementia Questionnaire for People with Learning Disabilities (DLD) rating (F_3,25  = 5.13; P = 0.007). Both the SIB (β = 0.74; t = 2.71; P = 0.01) and DLD (β = -0.96; t = -3.87; P < 0.001) indicated greater impairment as global CBF decreased. Age was significantly associated with CBF among participants with DS. There was a non-linear effect of age, whereby CBF declined more rapidly after 45 years of age.

CONCLUSIONS

This preliminary study of CBF in DS indicates that cerebrovascular pathology may be a significant contributor to dementia in DS. CBF was associated with diagnosis, cognition and age. Notably, CBF decreases at a greater rate after age 45 and may represent a significant prodromal event in AD progression.

Mass distribution of wheelchair athletes assessed using DXA scans and biomechanical simulations

The anthropometries of elite wheelchair racing athletes differ to the generic, able-bodied anthropometries commonly used in computational biomechanical simulations. The impact of using able-bodied parameters on the accuracy of simulations involving wheelchair racing is currently unknown. In this study, athlete-specific mass segment inertial parameters of five elite wheelchair athletes were calculated using dual-energy X-ray absorptiometry scans. These were compared against commonly used anthropometrics parameters of data presented in the literature. A computational biomechanical simulation of wheelchair propulsion assessed the sensitivity of athlete-specific mass parameters using Kruskal-Wallis analysis, Mann-Whitney U analysis and Spearman correlations. Substantial between-athlete body mass distribution variances (thigh mass < 14.6% total body mass), and between-limb asymmetries (<62.4%; 3.1 kg) were observed. Compared to non-athletic able-bodied anthropometric data, wheelchair racing athletes demonstrated greater mass in the upper extremities (up to 3.8% total body mass), and less in the lower extremities (up to 9.8% total body mass). Computational simulations were sensitive to individual body mass distribution, with simulation outputs increasing by up to 12.5% when measured segment masses were 14.3% greater than the generic counterpart. These data suggest non-athletic, able-bodied mass segment inertial parameters are inappropriate for analysing elite wheelchair racing motion.

Partial nitrification enhances natural attenuation of nitrogen in a septic system plume

Natural attenuation of nitrogen (N) was investigated in a well characterized septic system plume at a campground in Ontario, Canada. Total inorganic N (TIN) concentrations in deeper portions of the plume were about one third of the septic tank value of 40.7mgL^-1. NH₄⁺ and NO₃^- isotopic characterization were used to provide insight into potential attenuation processes. Concentrations of NH₄⁺ and NO₃^- were highly variable in the plume, but approached the septic tank TIN value in some shallow zones and exhibited δ¹⁵N values like the tank value of +6‰. However, isotopic enrichment (up to +24‰ for NH₄⁺ and +45‰ for NO₃^-) and declining TIN concentrations in the deeper zones indicated that anaerobic ammonium oxidation contributed to the TIN attenuation. The degree of isotopic enrichment increased at lower NH₄⁺ concentrations and was consistent with Rayleigh-type distillation with an enrichment factor (Ɛ) of -5.1‰. Additionally, decreasing DOC values with depth and the concomitant enrichment of δ¹⁵N_NO3 and δ¹⁸O_NO3, suggested that denitrification was also active. The N attenuation observed in the Killarney plume was partly due to incomplete nitrification that occurred because of the shallow water table, which varied from only 0.2-0.7m below the tile bed infiltration pipes. Moreover, some of the monitoring locations with the shallowest water table distances from the infiltration pipes, had the highest degree of TIN attenuation (70-90%) in the plume. This behavior suggests that controlling water table distance from the infiltration pipes could be a useful mechanism for enhancing N attenuation in septic system plumes.

Changes over time in mental well-being, fruit and vegetable consumption and physical activity in a community-based lifestyle intervention: a before and after study

OBJECTIVES

There is a theoretical basis for believing that healthy lifestyle interventions can improve mental well-being and evidence to show that mental well-being is protective of future health. This study contributes to the evidence base by examining changes in mental well-being associated with the One Body One Life (OBOL) healthy lifestyle programme in a community setting in the West Midlands.

STUDY DESIGN

Quantitative, before and after the evaluation.

METHODS

We conducted a before and after study of the lifestyle intervention 'OBOL', a multi component intervention that includes exercise and healthy eating education. Mental well-being was measured with the Warwick-Edinburgh Mental Well-being Scale. Physical activity and fruit and vegetable consumption were self-reported. Measures were collected before and after the 12-week intervention and three months post completion. Non-parametric tests were used to assess differences between groups, and linear mixed models were used to assess change over time.

RESULTS

Four hundred and eighty-one (81% of attendees) adult participants completed a valid Warwick-Edinburgh Mental Well-being Scale before starting OBOL; of whom, 63.8% completed the Warwick-Edinburgh Mental Well-being Scale immediately post intervention and 25.2% at three months. Mental well-being levels increased significantly (P < 0.001) over the course of the intervention and were sustained at the three-month follow-up (baseline median Warwick-Edinburgh Mental Well-being Scale score = 48 [interquartile range 41-55], completion = 53 [interquartile range 46-57], 3-month follow-up = 52 [interquartile range 46-56]). Change in mental well-being was clinically significant after accounting for age and gender. Changes in both fruit and vegetable consumption and physical activity appeared to explain some but not all of the variation in mental well-being.

CONCLUSION

We found significant improvements in mental well-being among participants directly after the intervention which were sustained at the three-month follow-up. These findings contribute to a growing body of knowledge on the contribution of lifestyle interventions to promoting and sustaining mental well-being.

Can serial PEF measurements separate occupational asthma from allergic alveolitis?

BACKGROUND

Occupational asthma commonly results in work-related changes in serial peak expiratory flow (PEF) measurements. Whether alveolitis can result in similar changes is unknown.

AIMS

To identify differences and similarities of serial PEF between workers with occupational alveolitis and asthma seen during an outbreak investigation in a factory with metal-working fluid exposure.

METHODS

Workers with respiratory symptoms and rest-day improvement were identified by questionnaire. Each was asked to measure PEF 8 times daily for 4 weeks at home and work. Alveolitis was subsequently diagnosed from a validated scoring system including radiological changes, carbon monoxide diffusing capacity, bronchoalveolar lavage and biopsy results. Occupational asthma was confirmed with a positive Oasys score >2.5 and a mean rest-work PEF >16 l/min from serial 2-hourly PEF measurements. The Oasys PEF plotter calculated differences between rest and workdays for mean PEF, diurnal variation and the scores were used to confirm an occupational effect (Oasys, area between curve and time point). Records were compared between the alveolitis group and the group with occupational asthma without alveolitis.

RESULTS

Forty workers with occupational asthma and 16 with alveolitis had indistinguishable PEF changes on workdays in terms of magnitude (median reduction 18.5 and 16.1 l/min, respectively) and diurnal variation. Immediate reactions were more common with occupational asthma and late reactions more common with alveolitis.

CONCLUSIONS

PEF responses to metal-working fluid aerosols do not distinguish occupational asthma from alveolitis except in timing. They can be used to identify the workplace as the cause of asthma and also alveolitis.

(1)H-MRS metabolites in adults with Down syndrome: Effects of dementia

To determine if proton magnetic resonance spectroscopy (¹H-MRS) detect differences in dementia status in adults with Down syndrome (DS), we used ¹H-MRS to measure neuronal and glial metabolites in the posterior cingulate cortex in 22 adults with DS and in 15 age- and gender-matched healthy controls. We evaluated associations between ¹H-MRS results and cognition among DS participants. Neuronal biomarkers, including N-acetylaspartate (NAA) and glutamate-glutamine complex (Glx), were significantly lower in DS patients with Alzheimer's should probably be changed to Alzheimer (without ' or s) through ms as per the new naming standard disease (DSAD) when compared to non-demented DS (DS) and healthy controls (CTL). Neuronal biomarkers therefore appear to reflect dementia status in DS. In contrast, all DS participants had significantly higher myo-inositol (MI), a putative glial biomarker, compared to CTL. Our data indicate that there may be an overall higher glial inflammatory component in DS compared to CTL prior to and possibly independent of developing dementia. When computing the NAA to MI ratio, we found that presence or absence of dementia could be distinguished in DS. NAA, Glx, and NAA/MI in all DS participants were correlated with scores from the Brief Praxis Test and the Severe Impairment Battery. ¹H-MRS may be a useful diagnostic tool in future longitudinal studies to measure AD progression in persons with DS. In particular, NAA and the NAA/MI ratio is sensitive to the functional status of adults with DS, including prior to dementia.

•

¹H-MRS was used to compare demented and nondemented adults with Down syndrome.

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Neuronal biomarkers were lowest in demented adults with Down syndrome.

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Glial biomarkers including myoinositol were higher in demented adults with DS.

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Neuronal and glial biomarkers were correlated with cognition in Down syndrome.

Socio-economic status and overweight or obesity among school-age children in sub-Saharan Africa - a systematic review

Childhood overweight and obesity have emerged as a public health concern in sub-Saharan Africa. We conducted a systematic review with the aim to examine the association between socio-economic status (SES) and overweight or obesity among school-age children in sub-Saharan Africa. In March 2014 we searched five electronic databases for reports which presented cross-sectional data on prevalence levels of overweight or obesity stratified by SES groups among school-age children in sub-Saharan Africa. We used a random-effect model to pool the relative indexes of inequality of the association from the individual studies. In total, 20 reports satisfied the inclusion criteria providing results of 21 datasets. The risk of overweight or obesity in children from highest SES households was 5.28 times as high as that of children from lowest SES households (95% confidence interval [CI] 2.62 to 10.66). On subgroup analysis, this association was statistically significant for household income and composite SES measures but not for parental educational attainment and occupation type. Similarly, the risk of overweight or obesity in children attending affluent (private) schools was 15.94 times as high as that of children going to either urban or rural public schools (95% CI 5.82 to 43.68). The magnitude of the association tended to be stronger for area or school-type compared with composite measures. In summary, children from higher SES households and those attending private schools tended to be overweight and obese.

Evaluation of recruitment methods for a trial targeting childhood obesity: Families for Health randomised controlled trial

BACKGROUND

Recruitment to trials evaluating the effectiveness of childhood obesity management interventions is challenging. We report our experience of recruitment to the Families for Health study, a randomised controlled trial evaluating the effectiveness of a family-based community programme for children aged 6-11 years, versus usual care. We evaluated the effectiveness of active recruitment (contacting eligible families directly) versus passive recruitment (informing the community through flyers, public events, media).

METHODS

Initial approaches included passive recruitment via the media (newspapers and radio) and two active recruitment methods: National Child Measurement Programme (letters to families with overweight children) and referrals from health-care professionals. With slow initial recruitment, further strategies were employed, including active (e.g. targeted letters from general practices) and passive (e.g. flyers, posters and public events) methods. At first enquiry from a potential participant, families were asked where they heard about the study. Further quantitative (questionnaire) and qualitative data (one-to-one interviews with parents/carers), were collected from recruited families at baseline and 3-month follow-up and included questions about recruitment.

RESULTS

In total, 194 families enquired about Families for Health, and 115 (59.3 %) were recruited and randomised. Active recruitment yielded 85 enquiries, with 43 families recruited (50.6 %); passive recruitment yielded 99 enquiries with 72 families recruited (72.7 %). Information seen at schools or GP surgeries accounted for over a quarter of enquiries (28.4 %) and over a third (37.4 %) of final recruitment. Eight out of ten families who enquired this way were recruited. Media-led enquiries were low (5 %), but all were recruited. Children of families recruited actively were more likely to be Asian or mixed race. Despite extensive recruitment methods, the trial did not recruit as planned, and was awarded a no-cost extension to complete the 12-month follow-up.

CONCLUSIONS

The higher number of participants recruited through passive methods may be due to the large number of potential participants these methods reached and because participants may see the information more than once. Recruiting to a child obesity treatment study is complex and it is advisable to use multiple recruitment strategies, some aiming at blanket coverage and some targeted at families with children who are overweight.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN45032201 (Date: 18 August 2011).

Parent-only interventions in the treatment of childhood obesity: a systematic review of randomized controlled trials

BACKGROUND

An effective and cost-effective treatment is required for the treatment of childhood obesity. Comparing parent-only interventions with interventions including the child may help determine this.

METHODS

A systematic review of published and ongoing studies until 2013, using electronic database and manual searches.

INCLUSION CRITERIA

randomized controlled trials, overweight/obese children aged 5-12 years, parent-only intervention compared with an intervention that included the child, 6 months or more follow-up. Outcomes included measures of overweight.

RESULTS

Ten papers from 6 completed studies, and 2 protocols for ongoing studies, were identified. Parent-only groups are either more effective than or similarly effective as child-only or parent-child interventions, in the change in degree of overweight. Most studies were at unclear risk of bias for randomization, allocation concealment and blinding of outcome assessors. Two trials were at high risk of bias for incomplete outcome data. Four studies showed higher dropout from parent-only interventions. One study examined programme costs and found parent-only interventions to be cheaper.

CONCLUSIONS

Parent-only interventions appear to be as effective as parent-child interventions in the treatment of childhood overweight/obesity, and may be less expensive. Reasons for higher attrition rates in parent-only interventions need further investigation.

Two-year follow-up of the 'Families for Health' programme for the treatment of childhood obesity

BACKGROUND

The high prevalence of obesity in children in the UK warrants continuing public health attention. 'Families for Health' is a family-based group programme for the treatment of childhood obesity. Significant improvements in body mass index (BMI) z-score (-0.21, 95% CI: -0.35 to -0.07, P = 0.007) and other health outcomes were seen in children at a 9-month follow-up.

AIM

To undertake a 2-year follow-up of families who attended 'Families for Health' in Coventry, to assess long-term outcomes and costs.

METHODS

'Families for Health' is a 12-week programme with parallel groups for parents and children, addressing parenting skills, healthy lifestyles and emotional well-being. The intervention was delivered at a leisure centre in Coventry, England, with 27 overweight or obese children aged 7-13 years (18 girls, 9 boys) and their parents, from 21 families. A 'before-and-after' evaluation was completed with 19 (70%) children followed up at 2 years. The primary outcome was change in BMI z-score from baseline; secondary outcomes were children's quality of life, parent-child relationships, eating/activity habits and parents' mental health. Costs to deliver the intervention and to families were recorded.

RESULTS

Mean change in BMI z-score from baseline was -0.23 (95% CI: -0.42 to -0.03, P = 0.027) at the 2-year follow-up and eight (42%) children had a clinically significant reduction in BMI z-score. Significant improvements were seen in children's quality of life and eating habits in the home, while there were sustained reductions in unhealthy foods and sedentary behaviour. Fruit and vegetable consumption and parent's mental health were not significantly different at 2 years. Costs of the programme were £517 per family (£402 per child), equivalent to £2543 per unit reduction in BMI z-score.

CONCLUSIONS

Improvements in BMI z-score and certain other outcomes associated with the 'Families for Health' programme were sustained at the 2-year follow-up. 'Families for Health' is a promising new childhood obesity intervention, and a randomized controlled trial is now indicated.

Investigation of an Escherichia coli environmental benchmark for waterborne pathogens in agricultural watersheds in Canada

Canada's National Agri-Environmental Standards Initiative sought to develop an environmental benchmark for low-level waterborne pathogen occurrence in agricultural watersheds. A field study collected 902 water samples from 27 sites in four intensive agricultural watersheds across Canada from 2005 to 2007. Four of the sites were selected as reference sites away from livestock and human fecal pollution sources in each watershed. Water samples were analyzed for Campylobacter spp., Salmonella spp., Escherichia coli O157:H7, Cryptosporidium spp., Giardia spp., and the water quality indicator E. coli. The annual mean number of pathogen species was higher at agricultural sites (1.54 ± 0.07 species per water sample) than at reference sites (0.75 ± 0.14 species per water sample). The annual mean concentration of E. coli was also higher at agricultural sites (491 ± 96 colony-forming units [cfu] 100 mL(-1)) than at reference sites (53 ± 18 cfu 100 mL(-1)). The feasibility of adopting existing E. coli water quality guideline values as an environmental benchmark was assessed, but waterborne pathogens were detected at agricultural sites in 80% of water samples with low E. coli concentrations (<100 cfu 100 mL(-1)). Instead, an approach was developed based on using the natural background occurrence of pathogens at reference sites in agricultural watersheds to derive provisional environmental benchmarks for pathogens at agricultural sites. The environmental benchmarks that were derived were found to represent E. coli values lower than geometric mean values typically found in recreational water quality guidelines. Additional research is needed to investigate environmental benchmarks for waterborne pathogens within the context of the "One World, One Health" perspective for protecting human, domestic animal, and wildlife health.

Molecular subtypes of Campylobacter spp., Salmonella enterica, and Escherichia coli O157:H7 isolated from faecal and surface water samples in the Oldman River watershed, Alberta, Canada

Campylobacter spp., Salmonella enterica, and Escherichia coli O157:H7 isolated from 898 faecal, 43 sewage, and 342 surface water samples from the Oldman River were characterized using bacterial subtyping methods in order to investigate potential sources of contamination of the watershed. Among these pathogens, Campylobacter spp. were the most frequently isolated from faecal, sewage, and surface water samples (266/895, 11/43, and 91/342, respectively), followed by Salmonella (67/898, 8/43, and 29/342, respectively), and E. coli O157:H7 (16/898, 2/43, and 8/342, respectively). Salmonella Rubislaw was the most common serovar isolated from water. This serovar was also isolated from two wild bird species. Most other serovars isolated from water were either not isolated from animals or were isolated from multiple species. E. coli O157:H7 was predominantly isolated from cattle. The most common phage-types of this pathogen from cattle were also the most common among water isolates, and there were exact pulsed field gel electrophoresis and comparative genomic fingerprint matches between cattle, sewage, and water isolates. Campylobacters were commonly isolated from surface waters and faeces from most animal species. Restriction fragment length polymorphism of the Campylobacter flaA gene identified several location and host species-specific (cattle, goose, pig) fingerprints. Molecular subtyping of these bacterial pathogens shows considerable promise as a tool for determining the sources of faecal pollution of water.

A methods comparison for the isolation and detection of thermophilic Campylobacter in agricultural watersheds

Campylobacter species contribute to an enormous burden of enteric illnesses around the world. This study compared two different methods for detecting Campylobacter species in surface water samples from agricultural watersheds across Canada. One method was based on membrane filtration (MF) of 500 ml water samples followed by selective microaerophilic enrichment at 42 degrees C in Bolton broth, isolation of Campylobacter on CCDA, and subsequent identification confirmation by a PCR assay. The second method was based on centrifugation (CF) of 1000 ml water samples, followed by selective microaerophilic enrichment at 42 degrees C in Bolton broth, isolation of Campylobacter on Modified Karmali Agar, and subsequent identification confirmation by a different PCR assay. Overall comparison of the CF and MF methods indicated that both methods found Camylobacterjejuni to be the most commonly detected Campylobacter species in 699 water samples from four agricultural watersheds across Canada, and that C. jejuni frequency of occurrence was similar by both methods. However, the CF method detected significantly higher frequencies of Campylobactercoli (17%) and other Campylobacter species (13%) than the MF method (11% and 3%, respectively). It was frequently found that one method would detect Campylobacter in a water sample when the other method would not for a simultaneously collected, duplicate water sample. This study indicates that methods can have significantly different recovery efficiencies for Campylobacter species, and that caution is needed when comparing studies that report on the frequency of occurrence of waterborne Campylobacter at the genus level when different detection methods are used.

Pilot of "Families for Health": community-based family intervention for obesity

OBJECTIVE

To develop and evaluate "Families for Health", a new community based family intervention for childhood obesity.

DESIGN

Programme development, pilot study and evaluation using intention-to-treat analysis.

SETTING

Coventry, England.

PARTICIPANTS

27 overweight or obese children aged 7-13 years (18 girls, 9 boys) and their parents, from 21 families.

INTERVENTION

Families for Health is a 12-week programme with parallel groups for parents and children, addressing parenting, lifestyle change and social and emotional development.

MAIN OUTCOME MEASURES

Change in baseline BMI z score at the end of the programme (3 months) and 9-month follow-up. Attendance, drop-out, parents' perception of the programme, child's quality of life and self-esteem, parental mental health, parent-child relationships and lifestyle changes were also measured.

RESULTS

Attendance rate was 62%, with 18 of the 27 (67%) children completing the programme. For the 22 children with follow-up data (including four who dropped out), BMI z score was reduced by -0.18 (95% CI -0.30 to -0.05) at 3 months and -0.21 (-0.35 to -0.07) at 9 months. Statistically significant improvements were observed in children's quality of life and lifestyle (reduced sedentary behaviour, increased steps and reduced exposure to unhealthy foods), child-parent relationships and parents' mental health. Fruit and vegetable consumption, participation in moderate/vigorous exercise and children's self-esteem did not change significantly. Topics on parenting skills, activity and food were rated as helpful and used with confidence by most parents.

CONCLUSIONS

Families for Health is a promising new childhood obesity intervention. Definitive evaluation of its clinical effectiveness by randomised controlled trial is now required.

Development of a rapid quantitative PCR assay for direct detection and quantification of culturable and non-culturable Escherichia coli from agriculture watersheds

A real-time quantitative polymerase chain reaction (Q-PCR) assay was developed for detecting and quantifying Escherichia coli in water samples from agricultural watersheds. The assay included optimization of DNA extraction and purification from water samples, and Q-PCR amplification conditions using newly designed species-specific oligonucleotide primers derived from conserved flanking regions of the 16S rRNA gene, the internal transcribed spacer region (ITS) and the 23S rRNA gene. The assay was optimized using a pure culture of E. coli with known quantities spiked into autoclaved agricultural water samples. The optimized assay was capable of a minimum quantification limit of 10 cells/ml of E. coli in the spiked agricultural water samples. A total of 121 surface water samples from three agricultural watersheds across Canada were analyzed, and results were compared with conventional culture-based enumerations of E. coli. The Q-PCR assay revealed significantly higher numbers of E. coli in water samples than the culture-based assay in each agricultural watershed. The new Q-PCR assay can facilitate the quantification of E. coli in a single water sample in < 3 h, including melt curve analysis, across a range of agricultural water quality conditions.

Clinical investigation of an outbreak of alveolitis and asthma in a car engine manufacturing plant

BACKGROUND

Exposure to metal working fluid (MWF) has been associated with outbreaks of extrinsic allergic alveolitis (EAA) in the USA, with bacterial contamination of MWF being a possible cause, but is uncommon in the UK. Twelve workers developed EAA in a car engine manufacturing plant in the UK, presenting clinically between December 2003 and May 2004. This paper reports the subsequent epidemiological investigation of the whole workforce. The study had three aims: (1) to measure the extent of the outbreak by identifying other workers who may have developed EAA or other work-related respiratory diseases; (2) to provide case detection so that those affected could be treated; and (3) to provide epidemiological data to identify the cause of the outbreak.

METHODS

The outbreak was investigated in a three-phase cross-sectional survey of the workforce. In phase I a respiratory screening questionnaire was completed by 808/836 workers (96.7%) in May 2004. In phase II 481 employees with at least one respiratory symptom on screening and 50 asymptomatic controls were invited for investigation at the factory in June 2004. This included a questionnaire, spirometry and clinical opinion. 454/481 (94.4%) responded and 48/50 (96%) controls. Workers were identified who needed further investigation and serial measurements of peak expiratory flow (PEF). In phase III 162 employees were seen at the Birmingham Occupational Lung Disease clinic. 198 employees returned PEF records, including 141 of the 162 who attended for clinical investigation. Case definitions for diagnoses were agreed.

RESULTS

87 workers (10.4% of the workforce) met case definitions for occupational lung disease, comprising EAA (n = 19), occupational asthma (n = 74) and humidifier fever (n = 7). 12 workers had more than one diagnosis. The peak onset of work-related breathlessness was Spring 2003. The proportion of workers affected was higher for those using MWF from a large sump (27.3%) than for those working all over the manufacturing area (7.9%) (OR = 4.39, p<0.001). Two workers had positive specific provocation tests to the used but not the unused MWF solution.

CONCLUSIONS

Extensive investigation of the outbreak of EAA detected a large number of affected workers, not only with EAA but also occupational asthma. This is the largest reported outbreak in Europe. Mist from used MWF is the likely cause. In workplaces using MWF there is a need to carry out risk assessments, to monitor and maintain fluid quality, to control mist and to carry out respiratory health surveillance.

Tracking host sources of Cryptosporidium spp. in raw water for improved health risk assessment

Recent molecular evidence suggests that different species and/or genotypes of Cryptosporidium display strong host specificity, altering our perceptions regarding the zoonotic potential of this parasite. Molecular forensic profiling of the small-subunit rRNA gene from oocysts enumerated on microscope slides by U.S. Environmental Protection Agency method 1623 was used to identify the range and prevalence of Cryptosporidium species and genotypes in the South Nation watershed in Ontario, Canada. Fourteen sites within the watershed were monitored weekly for 10 weeks to assess the occurrence, molecular composition, and host sources of Cryptosporidium parasites impacting water within the region. Cryptosporidium andersoni, Cryptosporidium muskrat genotype II, Cryptosporidium cervine genotype, C. baileyi, C. parvum, Cryptosporidium muskrat genotype I, the Cryptosporidium fox genotype, genotype W1, and genotype W12 were detected in the watershed. The molecular composition of the Cryptosporidium parasites, supported by general land use analysis, indicated that mature cattle were likely the main source of contamination of the watershed. Deer, muskrats, voles, birds, and other wildlife species, in addition to sewage (human or agricultural) may also potentially impact water quality within the study area. Source water protection studies that use land use analysis with molecular genotyping of Cryptosporidium parasites may provide a more robust source-tracking tool to characterize fecal impacts in a watershed. Moreover, the information is vital for assessing environmental and human health risks posed by water contaminated with zoonotic and/or anthroponotic forms of Cryptosporidium.

Effect of prepackage and postpackage pasteurization on postprocess elimination of Listeria monocytogenes on deli turkey products

Surface pasteurization for inactivation of Listeria monocytogenes was evaluated for radiant heat prepackage pasteurization, submersed water postpackage pasteurization, and combinations of the two techniques on various types of ready-to-eat deli turkey products obtained from at least four different manufacturers. Products were inoculated either by in-package liquid inoculum or surface sponge-contact with approximately 10(9) CFU of L. monocytogenes. Additional testing of radiant heat pasteurization was performed with low-level inoculation of product undersides with approximately 100 CFU of L. monocytogenes followed by enrichment recovery after pasteurization. Prepackage pasteurization provided 2.0 to 2.8 log reductions when processed for 60 s and 2.8 to 3.8 log reductions when processed for 75 s. An improved radiant oven provided 3.53 (60 s) and 4.76 (75 s) log reductions of L. monocytogenes. No positive samples were detected after enrichment when 40 samples of deli turkey (4 to 4.5 kg) undersides were inoculated at low levels and processed for 75 s. Submersed water postpackage pasteurization provided 1.95 to 3.0 log reductions when processed for 2, 3, 4, or 5 min, and combinations of the two processes gave 3.0 to 4.0 log inactivation of L. monocytogenes using either 60 + 60 s or 60 + 90 s for the prepackage and postpackage pasteurization processes, respectively. These processes, either individually or in combination, can provide postprocess elimination of bacteria for the manufacture of safe ready-to-eat deli meats.

Patterns of smoking, quit attempts and services for a cohort of 15- to 19-year-olds

OBJECTIVES

To establish patterns of smoking among 15-to 19-year-olds within mixed urban and suburban area and explore preference for the nature of services to assist quitting.

DESIGN

Postal survey and depth interviews with focus group validation.

SETTING

People registered with health services in the Borough of Solihull, UK. The borough has a diverse population with areas of high deprivation to the north and a range of prosperity elsewhere.

PARTICIPANTS

Questionnaires were sent to 50% of those registered and 20 people interviewed aged from 15 to 19 years.

MAIN OUTCOME MEASURES

The survey contained demographic questions relating to educational attainment and family, smoking status, history and quit attempts, use of facilities for quit attempts. Qualitative themes explored attitudes and experience of quitting, utilization of cessation services, barriers to access and nicotine replacement therapy.

RESULTS

Total survey response rate was 32.6%. Three in five reported smoking a cigarette sometime, 17.2% current regular smokers, 7.2% current occasional smokers. Median age of starting smoking was significantly lower (P = 0.004) for current regular smokers, distinguishable in two groups; weekend smokers and all week smokers. More quit attempts had been made or planned by current regular smokers but were often short lived. Weekend smokers had a slightly longer duration of quitting (P = 0.03). Eight-two per cent were optimistic about quitting in the future although the majority (80%) had already made one quit attempt. Knowledge and use of existing services was poor, with concerns about privacy and confidentiality. Models based on autonomy were identified as potentially useful.

CONCLUSION

Teenage smoking is characterized by optimism about quitting despite the failure of many quit attempts, lack of regard for existing services and barriers to uptake.

Comparison of the expression of p53, p21, Bax and the induction of apoptosis between patients with basal cell carcinoma and normal controls in response to ultraviolet irradiation

AIM

Ultraviolet light (UV) is known to cause DNA damage in the epidermis. The damaged DNA is repaired or deleted by apoptosis to prevent the generation of cancer. It has been suggested that a deficient apoptotic mechanism may predispose individuals to skin cancer. Therefore, the response of normal controls and patients with basal cell carcinoma (BCC) to UV irradiation was investigated.

METHODS

The buttock skin from normal volunteers and patients with BCC was irradiated using solar simulated radiation (SSR). SSR mimics the effect of natural sunlight. Skin biopsies were excised and examined for p53, p21, and Bax protein expression and for the induction of apoptosis.

RESULTS

At 33 hours after UV irradiation, the induction of apoptosis was significantly higher (p = 0.04) in patients with BCC than in normal volunteers (Mann Whitney test). A trend towards higher p21 expression was found at 33 hours in patients with BCC (mean, 18.69 positive cells/field) than in normal volunteers (mean, 9.89), although this difference was not significant (p = 0.05 positive cells/field).

CONCLUSION

These results may imply that patients with BCC have enhanced sensitivity to UV irradiation or that there is some defect in the cell arrest or repair pathways, which results in damaged cells been pushed into apoptosis rather than repair.

Telomerase activity detected in oral lichen planus by RNA in situ hybridisation: not a marker for malignant transformation

BACKGROUND

Oral lichen planus (OLP) is a chronic inflammatory condition. Clinically, it is characterised by the presence of a white lace-like lesion on the buccal mucosa, tongue, and gingivae, with erosions and ulceration. The World Health Organisation considers OLP to be a premalignant condition.

AIMS

To investigate expression of the telomerase RNA component (hTR) in OLP compared with normal control buccal mucosa and to assess the possibility of using hTR expression as a marker for malignant transformation in OLP.

METHODS

hTR expression was analysed in 40 cases of OLP and 18 normal control buccal mucosa samples using an RNA in situ hybridisation approach.

RESULTS

Strong hTR RNA expression was seen in the basal, suprabasal, and to a lesser extent in the upper epithelial layers in 36 of the 40 OLP lesions examined. Infiltrating subepithelial lymphocytes in OLP were also shown to express hTR RNA. Weak hTR RNA expression was seen in seven of the 18 normal control buccal mucosa specimens, with expression confined exclusively to the basal layer of the epithelium and absent in the suprabasal and upper layers.

CONCLUSION

The telomerase RNA component hTR is found to be highly expressed in the epithelium of non-dysplastic OLP lesions. It is possible that this high expression is related to the increased cellular proliferation seen in OLP lesions rather than being an indicator of susceptibility to malignancy. Thus, hTR RNA expression may not be a suitable marker for predicting malignant transformation in OLP.

The relationships of skeletal injuries with trauma score, injury severity score, length of hospital stay, hospital charges, and mortality in children admitted to a regional pediatric trauma center

Thirty-four-hundred and seventy-two children were consecutively admitted for acute traumatic injuries over a 34 month period to the Children's National Medical Center. The study comprised 805 patients who sustained 953 fractures and dislocations. The male to female ratio was 2:1. Age at the time of admission was evenly distributed over 16 years, with a mean of 8.3 years. Pedestrian accidents and falls each accounted for 34% of the musculoskeletal injuries, whereas motor vehicle accidents accounted for an additional 13%. The femur was the most commonly fractured bone, representing 22% of all fractures and dislocations, followed by the humerus (16%), tibia/fibula (12%), ankle/foot (13%), and radius/ulna (8%). Nine percent of the fractures were open. The average length of hospital stay was 8.6 days, and the average cost per hospital admission was $8,765. The mortality rate was 3%. Central musculoskeletal injuries (spine, clavicle/scapula, and pelvis) in our hospitalized patients were associated with the longest hospital stays and intensive care unit admissions, and lowest Trauma Scores, as well as the highest Injury Severity Scores, hospital charges, and mortality rates.

Effect of pre-slaughter overnight feed withdrawal on pig carcass and muscle quality

The effects of three feed withdrawal treatments (unfasted, 15 h overnight fast at the abattoir, 15 h overnight fast at the piggery) and three additional abattoir lairage times (0–1, 2–3 or 4–5 h) on pig carcass and non-carcass body component yields and on muscle quality characteristics were evaluated. Liveweight yield was lower (P < 0.05) for pigs fasted in the abattoir (by 17 g kg–1) and the piggery (by 22 g kg–1) than for unfasted pigs given a 2–5 h abattoir lairage. Of this decrease, 40–50% was attributed to a lower carcass yield, while the remainder was attributed to a decrease in yield of non-carcass components, especially the gastrointestinal tract. Feed withdrawal decreased (P < 0.05) the amount of distension of the intestinal tract, and increased (P < 0.05) the amount of carcass skin damage due to fighting. It had no effect (P > 0.05) on carcass lean yield, amount of shrink during the chilling process, yield of wholesale cuts, yields of dissected lean, fat and bone in the wholesale cuts, or moisture, fat and protein levels in the longissimus thoracis (LT) muscle. The overnight fast had little impact on LT muscle quality with the exception of slight darkening of the colour of muscles of pigs from which feed was withdrawn at the piggery. Feed withdrawal has the potential to reduce the problem of disposal of gut contents and the risk of carcass contamination as a result of nicking the gastrointestinal tract, and to slightly darken muscle tissue without affecting other meat quality traits. These benefits must be balanced against a decreased carcass yield and an increase in skin damage due to fighting. Key words: Feed restriction, fasting, gastrointestinal tract, gut fill, carcass yield, pork quality

Epidemic and endemic seroprevalence of antibodies to Cryptosporidium and Giardia in residents of three communities with different drinking water supplies

This study was carried out to compare cryptosporidiosis and giardiasis seroprevalence rates in residents of three communities. Community (Com 1) uses drinking water from deep wells, community 2 (Com 2) uses surface water from a protected watershed, and community 3 (Com 3) uses surface water frequently containing Cryptosporidium oocysts and Giardia cysts. Unfiltered drinking water from each community was collected at the tap and tested for Cryptosporidium oocysts and Giardia cysts during the 12 months in which sera were collected for testing. No oocysts or cysts were detected in the water from the Com 1 deep wells; oocysts and cysts were detected intermittently in the drinking water from the other two communities. A waterborne outbreak of cryptosporidiosis occurred in a municipality adjacent to Com 3 six months into this 12-month study. Sera from residents of each of the communities were collected proportionately by month and by population size. Coded sera were tested for IgG to Cryptosporidium using a previously developed Western blotting method. The presence or absence of bands at 15-17 kD and/or 27 kD was recorded for the 1,944 sera tested. Definite bands at 15-17 kD and/or 27 kD were detected in 981 (50.5%) of the sera. A total of 33.2% of sera from Com 1 (community using deep wells) were positive using the same criteria compared with 53.5% (Com 2) and 52.5% (Com 3) of sera from the two communities using surface drinking water. Both bands (15-17 kD plus 27 kD) were detected in 582 sera (29.9%) from the three communities: 14.1% of sera from Com 1 compared with 32.7% from Com 2 and 31.5% from Com 3. These findings are consistent with a lower risk of exposure to Cryptosporidium from drinking water obtained from deep well sources. However, analysis of results by calendar quarter showed a significant (P < 0.001) increase in the number of Com 3 positive sera (compared with Com 1) following the waterborne outbreak. Without this outbreak-related observation, a significant overall difference in seropositivity would not have been seen. We also observed that in sera from the community affected by the outbreak, the presence on immunoblots of both Cryptosporidium bands appeared to be the best indicator of recent infection. Seroprevalence rates using an ELISA to detect IgG to Giardia were estimated using the same sera. Overall 30.3% (590 of 1,944) of sera were positive by the ELISA. A total of 19.1% of sera from Com 1, 34.7% from Com 2 and 16.0% from Com 3 were seropositive. Rates for both Com 3 and Com 1 did not change significantly over time. In Com 2, rates decreased significantly (P < 0.001) during the last half of the study period (third and fourth calendar quarters). The reasons for the decrease in seroprevalence in Com 2 sera are presently not known. These studies show intriguing associations between seroprevalence, outbreak-related laboratory serologic data, and patterns of parasite contamination of drinking water. Further studies are required to validate the serologic approach to risk assessment of waterborne parasitic infections at a community level.

Endothelin-1 inhibits secretin-stimulated ductal secretion by interacting with ETA receptors on large cholangiocytes

We studied the expression of endothelin-1 (ET-1) receptors (ETA and ETB) and the effects of ET-1 on cholangiocyte secretion. The effects of ET-1 on cholangiocyte secretion were assessed in normal and bile duct-ligated (BDL) rats by measuring 1) basal and secretin-induced choleresis in vivo, 2) secretin receptor gene expression and cAMP levels in small and large cholangiocytes, and 3) luminal expansion in response to secretin in intrahepatic bile duct units (IBDU). ETA and ETB receptors were expressed by small and large cholangiocytes. ET-1 had no effect on basal bile flow or bicarbonate secretion in normal or BDL rats but decreased secretin-induced bicarbonate-rich choleresis in BDL rats. ET-1 decreased secretin receptor gene expression and secretin-stimulated cAMP synthesis in large cholangiocytes and secretin-induced luminal expansion in IBDU from normal or BDL rats. The inhibitory effects of ET-1 on secretin-induced cAMP synthesis and luminal duct expansion were blocked by specific inhibitors of the ETA (BQ-610) receptor. ET-1 inhibits secretin-induced ductal secretion by decreasing secretin receptor and cAMP synthesis, two important determinants of ductal secretion.

CSF, plasma viral load and HIV associated dementia

Plasma viral burden has proven valuable in predicting the future course of systemic HIV related disease and the response to treatment. It is not known whether plasma or cerebrospinal fluid (CSF) viral burden can be used to predict onset of or response to treatment of nervous system disease. We propose a model of viral load mediated neurotoxicity underlying peripheral and central HIV associated neurological disease. The objective of this preliminary study was to assess the relationship of HIV associated neurological disease to quantitative viral load in plasma and CSF. 47 subjects (HIV- = 10, HIV+ = 37) participated in the study. Plasma and CSF samples were collected within a 3 h window. RT-PCR (Roche Amplicor Monitor) was utilized to assess HIV-1 RNA viral load in both plasma and cell free (centrifuged) CSF. Subjects underwent concurrent comprehensive neurological and neuropsychological evaluations. In general, systemic viral load, as measured in plasma, was greater than that found in cell free CSF. Cell free CSF HIV RNA viral load was significantly correlated with neurological dysfunction, whereas plasma viral load was not. The sole subject with an elevated CSF viral load (> 5 Log 10), had HIV associated dementia (HAD) on clinical examination.

Bile acids stimulate proliferative and secretory events in large but not small cholangiocytes

Accumulation of bile acids (BA) and cholangiocyte proliferation occur in cholestasis, but BA effects on the proliferative and secretory capacity of cholangiocytes are undefined. Cholangiocyte proliferation coupled with increased expression of H3 histone and secretin receptor (SR) genes and secretin-stimulated adenosine 3',5'-cyclic monophosphate (cAMP) levels is limited to large cholangiocytes. We isolated pooled small and large cholangiocytes and studied the effect of taurocholic (TC) and taurolithocholic (TLC) acids on proliferation, by measurement of H3 histone gene expression, and secretion, by measurement of SR gene expression, cAMP levels, and Cl-/HCO3- exchanger activity. In pooled cholangiocytes, TC and TLC increased H3 histone (12-fold) and SR (3-fold) gene expression and both spontaneous (1.4-fold) and secretin-induced (4-fold) cAMP response. TC and TLC increased H3 histone (10-fold) and SR (2-fold) gene expression and secretin-induced cAMP response and Cl-/HCO3- exchanger activity (3-fold) only in large cholangiocytes. In large cholangiocytes, BA may have a signaling function in the modulation of ductal secretion.

Large but not small intrahepatic bile ducts are involved in secretin-regulated ductal bile secretion

We have shown that agonist-regulated ductal secretion is limited to large cholangiocytes. To directly study cholangiocyte heterogeneity along the length of the normal biliary tree, we defined the genetic and functional expression of agonist-induced ductal secretion in intrahepatic bile duct units (IBDU) of different sizes. Small IBDU (< 15-microns diam) were separated from large IBDU (> or = 15-microns diam), and then ducts of different sizes were characterized by morphometric analysis, gene expression, secretin-induced adenosine 3',5'-cyclic monophosphate (cAMP) synthesis, and secretion by change in luminal size in response to agonists. IBDU diameters ranged from 11 to 65 microns. Secretin increased ductal secretion solely in large IBDU. Forskolin induced a modest increase in ductal secretion in small IBDU but markedly increased ductal secretion in large IBDU. Secretion increased Cl-/HCO3- exchanger activity and cAMP levels in large but not small IBDU. Secretin receptor and Cl-/HCO3 exchanger mRNAs were detected only in large IBDU. We propose that agonist-induced ductal secretion occurs in large (> or = 15-microns diam) but not small (< 15-microns diam) intrahepatic ducts.

Polarized Growth of Fungal Hyphae Is Defined by an Alkaline pH Gradient

Robson, G. D., Prebble, E., Rickers, A., Hosking, S., Denning, D. W., Trinci, A. P. J., and Robertson, W. 1996. Polarized growth of fungal hyphae is defined by an alkaline pH gradient. Fungal Genetics and Biology 20, 289-298. Polarized cell growth is exhibited by a diverse range of eukaryotic and prokaryotic cells. The events which are responsible for this growth are poorly understood. However, the existence of ion gradients may play an important role in establishing and driving cell polarity. Using a pH-sensitive, ratiometric fluorescent dye to monitor intracellular pH in growing fungal hyphae, we report a gradient at the extending hyphal tip that is up to 1.4 pH units more alkaline than more distal regions. Both the magnitude and the length of the pH gradient were strongly correlated with the rate of hyphal extension and eradication of the gradient-arrested growth. These results suggest that alkaline pH gradients may be integral to hyphal extension in fungi.

Molecular techniques and their potential application in monitoring the microbiological quality of indoor air

Health effects associated with poor indoor air quality have created a need for accurate, reproducible methods of monitoring the microbiological content of indoor air. Improved methods of detection may allow researchers to clarify the effect of individual species present in the indoor environment on human health. This review discusses the shortcomings of current methods of identification and detection and focuses on the potential for molecular techniques in this emerging field. Probe techniques, restriction endonuclease analysis, karyotyping, and DNA and polymerase chain reaction fingerprinting methods available to detect and identify bacteria and fungi significant in the indoor air environment are discussed. Problems that may be encountered using these techniques are also considered. The authors have included a brief discussion on current air sampling techniques as well as adapting these techniques for use with molecular detection methods.

Does single dose salmeterol affect exercise capacity in asthmatic men?

The aim of this study was to investigate whether the long-acting beta-agonist salmeterol affects athletic performance in patients with asthma. The effect of 50 micrograms salmeterol on the cardiorespiratory responses to a progressive maximal cycle exercise test and on endurance capacity (defined as the exercise duration at 70% maximum oxygen uptake), was compared with 200 micrograms salbutamol and a matched placebo in eight asthmatic men. Both salmeterol and salbutamol improved pre- and postexercise forced expiratory volume in one second (FEV1) for maximal and endurance exercise. Following active treatment, patients exercised from a significantly high baseline FEV1, with both salmeterol (3.58(1.16)l) (mean (SD)) and salbutamol (3.55(1.24)l) compared with placebo (3.29(1.35)l). Similar improvements preceded endurance exercise. Cardiorespiratory, haemodynamic or subjective responses to the progressive maximum exercise tests were not different with salmeterol, salbutamol or placebo, nor did endurance capacity change with any treatment modality. Blood lactate levels, after 15 min exercise, were significantly higher with salbutamol (3.64 (1.83) mM), but not with salmeterol (3.03 (1.64) mM), compared with placebo (2.95 (1.69) mM). These results demonstrate the absence of significant cardiorespiratory or metabolic effects during exercise after a single dose of salmeterol, together with a lack-of ergogenic effect, as measured by maximal or endurance exercise performance, in patients with asthma.

Does single dose salmeterol affect exercise capacity in asthmatic men?

The aim of this study was to investigate whether the long-acting beta-agonist salmeterol affects athletic performance in patients with asthma. The effect of 50 micrograms salmeterol on the cardiorespiratory responses to a progressive maximal cycle exercise test and on endurance capacity (defined as the exercise duration at 70% maximum oxygen uptake), was compared with 200 micrograms salbutamol and a matched placebo in eight asthmatic men. Both salmeterol and salbutamol improved pre- and postexercise forced expiratory volume in one second (FEV1) for maximal and endurance exercise. Following active treatment, patients exercised from a significantly high baseline FEV1, with both salmeterol (3.58(1.16)l) (mean (SD)) and salbutamol (3.55(1.24)l) compared with placebo (3.29(1.35)l). Similar improvements preceded endurance exercise. Cardiorespiratory, haemodynamic or subjective responses to the progressive maximum exercise tests were not different with salmeterol, salbutamol or placebo, nor did endurance capacity change with any treatment modality. Blood lactate levels, after 15 min exercise, were significantly higher with salbutamol (3.64 (1.83) mM), but not with salmeterol (3.03 (1.64) mM), compared with placebo (2.95 (1.69) mM). These results demonstrate the absence of significant cardiorespiratory or metabolic effects during exercise after a single dose of salmeterol, together with a lack-of ergogenic effect, as measured by maximal or endurance exercise performance, in patients with asthma.

Effects of prolonged release recombinant porcine somatotropin and dietary protein on the growth, feed efficiency, carcass yield and meat quality of pigs

The effects of prolonged release recombinant porcine somatotropin (rpST) and dietary protein were tested in 108 Lacombe pigs, allocated to control or rpST treatments at 70 kg and fed isoenergetic diets containing one of three protein levels (14, 17 or 20% CP). Recombinant derived porcine somatotropin was implanted in the ear weekly (Monsanto Agricultural Co., St. Louis, #CP 115409, 12 mg wk−1). The control animals were given a weekly sham injection for a minimum of 4 wk. The prolonged release rpST had no effect on average daily gain (ADG, P > 0.05), but did reduce both the feed:gain ratio (F:G, P < 0.07) and dressing percentage (7 g kg−1 reduction, P < 0.05). Although both the fat thickness (10th rib) and kidney fat were reduced 5.6 and 13.9%, respectively, the absolute organ weights for kidneys, liver, lungs and gastrointestinal tract increased between 5 and 10% in prolonged release rpST treated pigs compared with control pigs (P < 0.05). Bone also increased by 6 g kg−1 (P < 0.05) in prolonged release rpST treated pigs, but carcass muscle or fat proportions were not different. Prolonged release rpST caused a higher ultimate muscle pH, moisture content and shear value (P < 0.06) and lower drip loss and expressable juice (P < 0.05) compared with meat from control carcasses. Increasing the dietary protein had no effect on ADG, but did improve the F:G ratio (P < 0.05). Carcass dressing proportion decreased with increasing protein level, but carcass lean content increased 5 g kg−1 for every 3% increase in crude protein. Simultaneous reductions in carcass fat, marbling and drip loss were observed (P < 0.05) as protein level increased. The data suggest that the current prolonged release rpST (12 mg pellets) shows marginal effects on growth and carcass composition. Some nutrient redirecting was apparent and improvements in the processing value of pork may result. Key words: Porcine somatrotropin, prolonged release, growth, diet, carcass, meat quality

Prenatal diagnosis and a donor splice site mutation in fibrillin in a family with Marfan syndrome

The Marfan syndrome, an autosomal dominant connective tissue disorder, is manifested by abnormalities in the cardiovascular, skeletal, and ocular systems. Recently, fibrillin, an elastin-associated microfibrillar glycoprotein, has been linked to the Marfan syndrome, and fibrillin mutations in affected individuals have been documented. In this study, genetic linkage analysis with fibrillin specific markers was used to establish the prenatal diagnosis in an 11-wk-gestation fetus in a four-generation Marfan kindred. At birth, skeletal changes suggestive of the Marfan syndrome were observed. Reverse transcription-PCR amplification of the fibrillin gene mRNA detected a deletion of 123 bp in one allele in affected relatives. This deletion corresponds to an exon encoding an epidermal growth factor-like motif. Examination of genomic DNA showed a G-->C transversion at the +1 consensus donor splice site.