To gate or not to gate: Revisiting drinking water microbial assessment through flow cytometry fingerprinting

Flow cytometry has been utilized for over a decade as a rapid and reproducible approach to assessing microbial quality of drinking water. However, the need for specialized expertise in gating-a fundamental strategy for distinguishing cell populations-introduces the potential for human error and obstructs the standardization of methods. This work conducts a comprehensive analysis of various gating approaches applied to flow cytometric scatter plots, using a dataset spanning a year. A sensitivity analysis is carried out to examine the impact of different gating strategies on final cell count results. The findings show that dynamic gating, which requires user intervention, is essential for the analysis of highly variable raw waters and distributed water. In contrast, static gating proved suitable for more stable water sources, interstage sample locations, and water presenting a particularly low cell count. Our conclusions suggest that cell count analysis should be supplemented with fluorescence fingerprinting to gain a more complete understanding of the variability in microbial populations within drinking water supplies. Establishing dynamic baselines for each water type in FCM monitoring studies is essential for choosing the correct gating strategy. FCM fingerprinting offers a dynamic approach to quantify treatment processes, enabling options for much better monitoring and control. This study offers new insights into the vagaries of various flow cytometry gating strategies, thereby substantially contributing to best practices in the water industry. The findings foster more efficient and reliable water analysis, improving of standardizing methods in microbial water quality assessment using FCM.

O-219 Donor conception and Commercial Genomics: how are donor conceived people, their parents and donors using direct-to-consumer genetic testing?

Study question

How do donor conceived people, their parents and donors use direct-to-consumer genetic testing (DTCGT)?

Summary answer

DTCGT is changing how information about donor conception is accessed and managed by parents, donors and donor conceived people.

What is known already

Following the development and rapid expansion of DTCGT, there have been claims that ‘anonymity is dead’ in relation to donor conception (Darroch & Smith, 2021; Harper et al., 2016). Small-scale studies (Crawshaw, 2018) and media articles have reported that donor conceived adults are often finding out about the circumstances of their conception after using DCTGT.  However, there is a gap in the evidence about how donor conceived people already aware of their donor conception, as well as parents through donor conception and donors, are  using DTCGT.

Study design, size, duration

The ConnecteDNA project is an ongoing qualitative research study (March 2021-February 2024). It investigates how people in the UK, involved in donor conception, are impacted by DTCGT and considers the implications for policy and practice. This presentation focusses on phase two of the project: in-depth interviews with parents through donor conception, donors and donor conceived adults who have used, or considered using, DTCGT.

Participants/materials, setting, methods

So far, six donors, 13 parents through donor conception and 18 donor conceived adults have been interviewed via telephone or video call. Interviews are ongoing until September 2022.  Participants were recruited by advertising the project via a range of support groups and organisations for donor conception and/or DTCGT user communities.

Main results and the role of chance

Our findings show that people involved in UK donor conception are using DCTGT to access and manage information about donor conception. This includes donor conceived people, previously unaware of the circumstances of their conception, discovering they are donor conceived after using DTCGT. We have found that donor conceived people, already aware that they are donor conceived, may also use DTCGT in search of information about ‘donor relatives’ and/or their genetic make-up, including understandings of their ethnicity and health risks. Furthermore, some donors are using DTCGT to make themselves contactable to people conceived via their donation(s), whilst others are traced via relatives who have used DTCGT. Parents through donor conception may use, or consider using DTCGT, to trace people related to their children through donor conception. This may be done when the child is very young, with the intention of finding relatives (particularly half siblings) who they can then grow up with. Others take a more responsive approach, only using DTCGT to support a child’s request or interest in more information. DTCGT is also used to trace genetic relatives alongside, or instead of, ‘official’ routes for accessing information about donor conception, as well as social media and public records.

Limitations, reasons for caution

Participants in this study are self-selecting and some groups may be under-represented in our sample (e.g. fathers through donor conception). We make no claims regarding the relative prevalence of different views and experiences. However, findings demonstrate the range of ways in which people involved in donor conception are using DTCGT.

Wider implications of the findings

DTCGT is transforming how people involved in donor conception seek information about genetic relatives. UK law and HFEA policies will require reform to account for this. Professionals who work with people using, or considering, donor conception, should make their clients aware of the potential uses and outcomes of DTCGT.

Trial registration number

Not applicable

O-097 The presentation of medical risks and incentives in egg donation: an analysis of Belgian, Spanish and UK fertility clinic websites

Study question

How do fertility clinics’ websites of the UK, Belgium and Spain present the medical risks of egg donation and incentives?

Summary answer

Spanish and UK websites typically included more incentives to recruit egg donors compared to the Belgian websites. OHSS was overall the most discussed risk.

What is known already

People commonly turn to the internet for initial information. Primary presentations of information of a subject co-determine how an individual interprets the topic and thus influence later decisions. Considering the growing demand and clinics’ dependency on egg donors, some scholars have expressed concerns that clinics might (initially) misrepresent risks to recruit more egg donors. Offering appealing incentives may also encourage potential donors to dismiss possible risks and side-effects.

Therefore, it is important to see how incentives (both monetary and non-monetary rewards) and risks are presented on the websites of fertility clinics, the first source of information for egg donors.

Study design, size, duration

This study is part of the EDNA-project, a multi-phased comparative study (2017-2021), that aims to explore the social, political, economic and moral configuration of egg donation in the United Kingdom, Belgium and Spain. In this study, we only focused on the medical risks of egg donation and incentives presented on the fertility clinics’ websites of the three countries.

Participants/materials, setting, methods

We analysed the websites of all Belgian fertility clinics (n = 18), and a maximum variation sample in the UK (n = 21) and Spain (n = 23). The sampling was based on the geographical location of the clinic, size/number of cycles performed each year, the clinic’s status (independent or part of a larger clinical group) and whether the clinic was public or privately funded in the UK. Frame analysis and content analysis were used for analysis in Nvivo12.

Main results and the role of chance

No misrepresentation of risks was found. There was an extensive variety in the representation of risks. There were differences between the websites of the three countries (e.g. the risks of having acne was only discussed on Spanish websites), but also remarkable differences within the websites of a particular country (of the 40 risks, 13 were one-off mentions, each found on a single website). A description of a risk was generally accompanied by a minimization or normalization of the risk, or a statement about the fertility clinic’s excellent care for their egg donors. These three approaches were often combined.

Our analysis differentiated between incentives (i.e. external rewards) and emotional appeals. An appeal to emotions (e.g. empathy) can also motivate behavioural action (e.g. donation) but was not considered as an incentive since there is no external reward.

While Belgian websites used almost no incentives, Spanish and UK websites used gratitude and a rewarding experience as incentives. However, only Spanish websites used free medical tests as incentives, while UK websites were the only ones that used discounts received with egg sharing as an incentive. All countries’ websites used emotional appeals by enticing feelings of empathy for the recipients.

Limitations, reasons for caution

Not all UK and Spanish fertility clinics’ websites were analysed. However, our international team of researchers applied a maximum variation sampling strategy. This generated samples of clinics per country that were as diversified as possible.

Wider implications of the findings

The study shows that incentives are more often used on the UK and Spanish websites than on the Belgian websites. All three countries’ websites used emotional appeals. It should be studied how effective these incentives and emotional appeals are, and if there is a correlation with the potential donors’ risk-perceptions.

Trial registration number

not applicable

A qualitative study of the impact of endometriosis on male partners

STUDY QUESTION

What is the impact of endometriosis on male partners of women with the condition?

SUMMARY ANSWER

Endometriosis significantly impacts men across several life domains and can negatively impact emotional well-being.

WHAT IS KNOWN ALREADY

Endometriosis has been shown to negatively impact women's quality of life and may strain intimate relationships. Little is known about the impact on male partners.

STUDY DESIGN, SIZE, DURATION

The ENDOPART study was a cross-sectional, qualitative study of 22 women with endometriosis and their male partners (n = 44) in the UK (2012–2013).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Inclusion criteria: laparoscopic diagnosis of endometriosis; the presence of symptoms for at least a year; partners living together. Data were collected via face to face, semi structured interviews with partners interviewed separately. Data were analysed thematically, assisted by NVivo 10.

MAIN RESULTS AND THE ROLE OF CHANCE

Men reported that endometriosis affected many life domains including sex and intimacy, planning for and having children, working lives and household income. It also required them to take on additional support tasks and roles. Endometriosis also had an impact on men's emotions, with responses including helplessness, frustration, worry and anger. The absence of professional or wider societal recognition of the impact on male partners, and a lack of support available to men, results in male partners having a marginalized status in endometriosis care.

LIMITATIONS REASONS FOR CAUTION

Self-selection of participants may have resulted in a sample representing those with more severe symptoms. Couples included are in effect ‘survivors’ in relationship terms, therefore, findings may underestimate the contribution of endometriosis to relationship breakdown.

WIDER IMPLICATIONS OF THE FINDINGS

The study extends knowledge about the impact of endometriosis on relationships, which thus far has been drawn largely from studies with women, by providing new insights about how this condition affects male partners. Healthcare practitioners need to take a more couple-centred, biopsychosocial approach toward the treatment of endometriosis, inclusive of partners and relationship issues. The findings demonstrate a need for information and support resources aimed at partners and couples.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the Economic and Social Research Council (reference ES/J003662/1). The authors have no conflicts of interest.

Dose-dependent expression of claudin-5 is a modifying factor in schizophrenia

Schizophrenia is a neurodevelopmental disorder that affects up to 1% of the general population. Various genes show associations with schizophrenia and a very weak nominal association with the tight junction protein, claudin-5, has previously been identified. Claudin-5 is expressed in endothelial cells forming part of the blood-brain barrier (BBB). Furthermore, schizophrenia occurs in 30% of individuals with 22q11 deletion syndrome (22q11DS), a population who are haploinsufficient for the claudin-5 gene. Here, we show that a variant in the claudin-5 gene is weakly associated with schizophrenia in 22q11DS, leading to 75% less claudin-5 being expressed in endothelial cells. We also show that targeted adeno-associated virus-mediated suppression of claudin-5 in the mouse brain results in localized BBB disruption and behavioural changes. Using an inducible 'knockdown' mouse model, we further link claudin-5 suppression with psychosis through a distinct behavioural phenotype showing impairments in learning and memory, anxiety-like behaviour and sensorimotor gating. In addition, these animals develop seizures and die after 3-4 weeks of claudin-5 suppression, reinforcing the crucial role of claudin-5 in normal neurological function. Finally, we show that anti-psychotic medications dose-dependently increase claudin-5 expression in vitro and in vivo while aberrant, discontinuous expression of claudin-5 in the brains of schizophrenic patients post mortem was observed compared to age-matched controls. Together, these data suggest that BBB disruption may be a modifying factor in the development of schizophrenia and that drugs directly targeting the BBB may offer new therapeutic opportunities for treating this disorder.

Enhanced expression of proteins involved in energy production and transfer in breast muscle of pedigree male broilers exhibiting high feed efficiency

In cells with fluctuating energy demand (e.g., skeletal muscle), a transfer system of proteins across the inner and outer mitochondrial membranes links mitochondrial oxidative phosphorylation to cytosolic phosphorylated creatine (PCr) that serves as a phosphate reservoir for rapid repletion of cytosolic adenosine triphosphate (ATP). Crucial proteins of this energy transfer system include several creatine kinase (CK) isoforms found in the cytosol and mitochondria. In a recent proteomic study (Kong et al., 2016), several components of this system were up-regulated in high feed efficiency (FE) compared to low FE breast muscle; notably adenine nucleotide translocase (ANT), voltage dependent activated channel (VDAC), the brain isoform of creatine kinase (CK-B), and several proteins of the electron transport chain. Reexamination of the original proteomic dataset revealed that the expression of two mitochondrial CK isoforms (CKMT1A and CKMT2) had been detected but were not recognized by the bioinformatics program used by Kong et al. (2016a). The CKMT1A isoform was up-regulated (7.8-fold, P = 0.05) in the high FE phenotype but there was no difference in CKMT2 expression (1.1-fold, P = 0.59). From these findings, we hypothesize that enhanced expression of the energy production and transfer system in breast muscle of the high FE pedigree broiler male could be fundamentally important in the phenotypic expression of feed efficiency.

Comparison of odour emission rates measured from various sources using two sampling devices

Two commonly used sampling devices (a wind tunnel and the US EPA dynamic emission chamber), were used to collect paired samples of odorous air from a number of agricultural odour sources. The odour samples were assessed using triangular, forced-choice dynamic olfactometry. The odour concentration data was combined with the flushing rate data to calculate odour emission rates for both devices on all sources. Odour concentrations were consistently higher in samples collected with a flux chamber (ratio ranging from 10:7 to 5:1, relative to wind tunnel samples), whereas odour emission rates were consistently larger when derived from wind tunnels (ratio ranging from 60:1 to 240:1, relative to flux chamber values). A complex relationship existed between emission rate estimates derived from each device, apparently influenced by the nature of the emitting surface. These results have great significance for users of odour dispersion models, for which an odour emission rate is a key input parameter.

Long-term assessment of efficacy of permeable pond covers for odour reduction

Three anaerobic ponds used to store and treat piggery wastes were fully covered with permeable materials manufactured from polypropylene geofabric, polyethylene shade cloth and supported straw. The covers were assessed in terms of efficacy in reducing odour emission rates over a 40-month period. Odour samples were collected from the surface of the covers, the surface of the exposed liquor and from the surface of an uncovered (control) pond at one of the piggeries. Relative to the emission rate of the exposed liquor at each pond, the polypropylene, shade cloth and straw covers reduced average emission rates by 76%, 69% and 66%, respectively. At the piggery with an uncovered control pond, the polypropylene covers reduced average odour emission rates by 50% and 41%, respectively. A plausible hypothesis, consistent with likely mechanisms for the odour reduction and the olfactometric method used to quantifying the efficacy of the covers, is offered.

Odour sampling 1: Physical chemistry considerations

The selection of an odour sampling device may influence the composition of the resulting odour sample. Limited comparison of emission rates derived from turbulent and essentially quiescent sampling devices confirms that the emission rates derived from these devices are quite different. There is therefore compelling evidence that current odour sampling practice should have greater regard for fundamental physical and chemical principles, the nature of the odour source and the conditions created by the sampling device. Such consideration may identify the most appropriate situations under which the use of these devices may or may not be correct.

Odour sampling. 2. Comparison of physical and aerodynamic characteristics of sampling devices: a review

Sampling devices differing greatly in shape, size and operating condition have been used to collect air samples to determine rates of emission of volatile substances, including odour. However, physical chemistry principles, in particular the partitioning of volatile substances between two phases as explained by Henrys Law and the relationship between wind velocity and emission rate, suggests that different devices cannot be expected to provide equivalent emission rate estimates. Thus several problems are associated with the use of static and dynamic emission chambers, but the more turbulent devices such as wind tunnels do not appear to be subject to these problems. In general, the ability to relate emission rate estimates obtained from wind tunnel measurements to those derived from device-independent techniques supports the use of wind tunnels to determine emission rates that can be used as input data for dispersion models.

Odour emissions from anaerobic piggery ponds. 2: improving estimates of emission rate through recognition of spatial variability

Odour emission rates were measured for seven different anaerobic ponds treating piggery wastes at six to nine discrete locations across the surface of each pond on each sampling occasion over a thirteen month period. Significant variability in emission rates were observed for each pond. Measurement of a number of water quality variables in pond liquor samples collected at the same time and from the same locations as the odour samples indicated that the composition of the pond liquor was also variable. The results indicated that spatial variability was a real phenomenon and could have a significant impact on odour assessment practices. Considerably more odour samples would be required to characterise pond emissions than currently recommended by most practitioners, or regulatory agencies.

Odour emissions from anaerobic piggery ponds. 1. Results of a three season, 14-month survey

Odour emission rates were measured for seven different anaerobic ponds treating piggery wastes at six to nine discrete locations across the surface of each pond on each sampling occasion over a 14-month period. Emission rate values varied between ponds, between seasons for the same pond and even for the same pond on different days of a sampling week. Average seasonal emission rates ranged from 7.9 to 46.5OU/m(2)s, while average emission rates ranged from 16.0 to 29.0OU/m(2)s. Factors potentially responsible for the variability in emission rates were investigated, including air and pond liquor temperatures, time of day of sample collection, season and the impact of a prolonged drought.

Biopattern analysis and subject-specific diagnosis and care of dementia

Worldwide, the number of people that develop Alzheimer's disease and other types of dementia is rapidly rising and will create a considerable financial burden on the health and social services. The availability of new drugs that may slow or even halt the disease progression makes accurate early detection crucial. Objective methods are needed to support clinical diagnosis and care for patients; to quantify severity, monitor progression and response to new treatments. Electrophysiological markers have an important role to play in the objective assessment and care for dementia. The EEG provides a measure of brain dysfunction and EEG changes could be detected fairly early in the dementing process. Subject-specific EEG analysis offers the possibility of using objective methods to assess and care for dementia on an individual basis. The main objectives of this paper are: (i) to introduce the concepts of subject-specific EEG analysis as a basis for improving diagnosis and care for dementia; and (ii) present two novel methods for deriving suitable subject-specific electrophysiological markers analysis of fractal dimension and zero crossing interval density of the EEG. We present findings that indicate that the methods are potentially good candidates for the development of individualized, low-cost, easy to administer and reasonably accurate methods for detecting dementia within the growing at risk population.

Nonlinear methods for biopattern analysis: role and challenges

An important trend in medical technology is towards support for personalised healthcare, fuelled by developments in genomic-based medicine. New computational intelligent techniques for biodata analysis will be needed to fully exploit the vast amounts of data that are being generated. Non-linear signal processing methods will form an important part of such computational intelligent techniques. This paper introduces some non-linear methods which are likely to play a role in the emerging area of biopattern and bioprofile analysis that will underpin personalized healthcare. We highlight their application to clinical problems involving EEG and fetal ECG and heart rate analysis, and issues that arise when they are applied to real world problems. The clinical problems include dementia assessment, drug administration and fetal monitoring. The potential role and challenges in the application of non-linear signal analysis of biopattern and bioprofile are highlighted within the context of a major EU project, BIOPATTERN.

Assessment of permeable covers for odour reduction in piggery effluent ponds. 1. Laboratory-scale trials

A variety of materials were trialed as supported permeable covers using a series of laboratory-scale anaerobic digesters. Efficacy of cover performance was assessed in terms of impact on odour and greenhouse gas emission rate, and the characteristics of anaerobic liquor. Data were collected over a 12-month period. Initially the covers reduced the rate of odour emission 40-100 times relative to uncovered digesters. After about three months, this decreased to about a threefold reduction in odour emission rate, which was maintained over the remainder of the trial. The covers did not alter methane emission rates. Carbon dioxide emission rates varied according to cover type. Performance of the covers was attributed to the physical characteristics of the cover materials and changes in liquor composition. The reductions in odour emission indicate that these covers offer a cost-effective method for odour control.

Assessment of permeable covers for odour reduction in piggery effluent ponds. 2. Field-scale trials

The efficacy of supported covers was investigated under field conditions using a series of prototypes deployed on an anaerobic pond treating typical piggery waste. Research focused on identifying effective cover support materials and deployment methods, quantifying odour reduction, and estimating the life expectancy of various permeable cover materials. Over a 10-month period, median odour emission rates were five to eight times lower from supported straw cover surfaces and a non-woven, spun fibre polypropylene weed control material than from the adjacent uncovered pond surface. While the straw covers visually appeared to degrade very rapidly, they continued to reduce odour emissions effectively. The polypropylene cover appeared to offer advantages from the perspectives of cost, reduced maintenance and ease of manufacture.

Treatment of vulval Crohn's disease with infliximab

Anti-tumour necrosis factor-alpha therapy of Crohn's disease (CD) with infliximab has proved a major advance in the treatment of patients with difficult disease. We report our experience of the use of infliximab in a patient with recalcitrant vulval CD. The introduction of infliximab has improved disease control, although a search for an optimum remittive dosing schedule is ongoing.

Resumption of follicle growth in gilts after ovarian autografting

The aims of the study were to evaluate autografting of porcine ovarian tissue in terms of establishment of a blood supply, follicle survival and development, commencement of oestrous cycles and endocrine patterns in this polyovular species. Experiment 1, a preliminary study on four gilts, showed that ovarian tissue slices survived the grafting procedure and re-vascularised. In Experiment 2, a further six pre-pubertal gilts had both ovaries surgically removed and two thin cortical slices of each ovary were immediately reattached to each of the ovarian pedicles. Blood samples were taken at surgery and then weekly. Two gilts were slaughtered 2 weeks after surgery and ovarian tissue recovered. The remaining four gilts underwent daily checks for behavioural oestrus until slaughter 24 weeks after surgery. All four gilts showed standing heat at least once prior to slaughter. Plasma LH and FSH concentrations increased significantly (P<0.01) by 3 days after surgery, then fell gradually, but did not return to pre-surgery levels. Progesterone concentrations showed some evidence of cyclicity in all animals. In the grafted tissue, re-vascularisation of the tissue was apparent by 2 weeks post-grafting, although no preantral or antral follicles were observed. The tissue recovered after 24 weeks contained healthy preantral and antral follicles, luteal tissue and some large cystic follicles. It is unclear whether these cysts were the result of ovarian or hypothalamic/pituitary disturbance. In conclusion, the results of this study have shown that follicle growth and resumption of cyclicity can be achieved following ovarian autografting in pigs and indicate that this will be a useful model for investigating the mechanisms that control the early stages of follicular growth and ultimately ovulation rate in this multiovular species.

Evaluation of a novel wind tunnel for the measurement of the kinetics of odour emissions from piggery effluent

A novel laboratory wind tunnel, with the capability to control factors such as air flow-rate, was developed to measure the kinetics of odour emissions from liquid effluent. The tunnel allows the emission of odours and other volatiles under an atmospheric transport system similar to ambient conditions. Sensors for wind speed, temperature and humidity were installed and calibrated. To calibrate the wind tunnel, trials were performed to determine the gas recovery efficiency under different air flow-rates (ranging from 0.001 to 0.028m3/s) and gas supply rates (ranging from 2.5 to 10.0 L/min) using a standard CO gas mixture. The results have shown gas recovery efficiencies ranging from 61.7 to 106.8%, while the average result from the trials was 81.14%. From statistical analysis, it was observed that the highest, most reliable gas recovery efficiency of the tunnel was 88.9%. The values of air flow-rate and gas supply rate corresponding to the highest gas recovery efficiency were 0.028 m3/s and 10.0 L/min respectively. This study suggested that the wind tunnel would provide precise estimates of odour emission rate. However, the wind tunnel needs to be calibrated to compensate for errors caused by different air flow-rates.

The relation between Ashworth scale scores and the excitability of the alpha motor neurones in patients with post-stroke muscle spasticity

BACKGROUND

The modified Ashworth scale (MAS) is the most widely used method for assessing muscle spasticity in clinical practice and research. However, the validity of this scale has been challenged.

OBJECTIVES

To compare the MAS with objective neurophysiological tests of spasticity.

METHODS

The MAS was recorded in patients with post-stroke lower limb muscle spasticity and correlated with the excitability of the alpha motor neurones. The latter was evaluated by measuring the latency of the Hoffmann reflex (H reflex) and the ratio of the amplitude of the maximum H reflex (H(max)) to that of the compound action motor potential of the soleus muscle (M(max)).

RESULTS

Data on 24 randomly recruited patients were analysed. Patients were divided into two groups according to their MAS score: 14 had a MAS score of 1 (group A) and 10 scored 2 (group B). The two groups were comparable with respect to age and sex, but in group A there was a longer period since the stroke. The H reflex latency was reduced and the H(max):M(max) ratio was increased in both groups. The H(max):M(max) ratio values were higher for group B but the differences were not statistically significant.

CONCLUSIONS

There is a relation between the MAS scores and alpha motor neurone excitability, although it is not linear. This suggests that the MAS measures muscle hypertonia rather than spasticity.

Multicentre, prospective, randomized trial of 4 vs. 6 French catheters in 410 patients undergoing coronary angiography

The aim of this study was to assess the quality of angiograms obtained using 4 Fr catheters compared with 6 Fr catheters, the ease of use of the 4 Fr catheters, and the safety of patient mobilization 1 hr following 4 Fr angiography. Details of catheter performance and procedural details were recorded at the time of the angiogram. The angiographic images were scored on the quality and completeness of vessel opacification throughout systole and diastole. A total of 410 patients were recruited. There was no difference between 4 and 6 Fr for procedural variables. All angiograms were considered to be of diagnostic quality. The angiographic scores for the right coronary artery and left ventricular injections were no different between 4 and 6 Fr. However, the angiographic scores for the left anterior descending and circumflex arteries were lower with 4 than with 6 Fr (both P < 0.05). Patients who had 4 Fr angiography mobilized safely at 1 hr and reported significantly less discomfort and bruising than 6 Fr patients. Good-quality diagnostic coronary angiograms can be achieved using 4 Fr catheters with the advantage of earlier postprocedural mobilization and reduced discomfort and bruising for the patient.

A reduction in interstitial cells of Cajal in horses with equine dysautonomia (grass sickness)

Equine dysautonomia (grass sickness) is a common, frequently fatal disease of horses characterised by dysfunction of the gastrointestinal tract. Interstitial cells of Cajal are the c-Kit-immunoreactive cells responsible for the generation of pacemaker activity in gastrointestinal smooth muscle. Impairment of this pacemaker action has been implicated in several motility disorders in humans and laboratory mammals. The aim of this study was to test the hypothesis that changes in interstitial cells of Cajal may be involved in the pathophysiology of the intestinal dysfunction observed in equine grass sickness. Interstitial cells of Cajal were identified using immunohistochemical labelling with an anti-c-Kit antibody and their density was assessed using a semi-quantitative grading system. Segments of ileum were examined from 24 horses free from gastrointestinal disease and compared to tissues from 28 horses with grass sickness. Segments of the pelvic flexure region of the large colon were examined from 13 horses free from gastrointestinal disease and compared to tissues from 10 horses with grass sickness. In horses with grass sickness, interstitial cells of Cajal were significantly decreased in both the myenteric plexus and circular muscle regions of both ileum and pelvic flexure compared to normal animals. Therefore, it is possible that the decline in interstitial cells of Cajal may be an important factor in the development of intestinal dysmotility observed in grass sickness.

Sequencing batch reactor technology: the key to a BP refinery (Bulwer Island) upgraded environmental protection system--a low cost lagoon based retro-fit

BP Refinery (Bulwer Island) Ltd (BP) located on the eastern Australian coast is currently undergoing a major expansion as a part of the Queensland Clean Fuels Project. The associated wastewater treatment plant upgrade will provide a better quality of treated effluent than is currently possible with the existing infrastructure, and which will be of a sufficiently high standard to meet not only the requirements of imposed environmental legislation but also BP's environmental objectives. A number of challenges were faced when considering the upgrade, particularly; cost constraints and limited plot space, highly variable wastewater, toxicity issues, and limited hydraulic head. Sequencing Batch Reactor (SBR) Technology was chosen for the lagoon upgrade based on the following; SBR technology allowed a retro-fit of the existing earthen lagoon without the need for any additional substantial concrete structures, a dual lagoon system allowed partial treatment of wastewaters during construction, SBRs give substantial process flexibility, SBRs have the ability to easily modify process parameters without any physical modifications, and significant cost benefits. This paper presents the background to this application, an outline of laboratory studies carried out on the wastewater and details the full scale design issues and methods for providing a cost effective, efficient treatment system using the existing lagoon system.

Laboratory investigation of supported permeable organic covers for the management of odour emissions from anaerobic piggery waste ponds

Australian research has linked much of the odour arising from intensive livestock operations to pond treatment systems. A reduction in emissions from treatment ponds would therefore generally reduce odour emissions from intensive livestock operations. Published data indicates that the application of straw and other biological materials to effluent pond surfaces as a continuous cover reduces odour emissions. The effectiveness of these covers has not, however, been researched under controlled conditions. Using locally available materials, the efficacy of supported covers has been investigated using a series of laboratory anaerobic digesters treating typical piggery effluent. Research to date has focused on: identifying effective cover and cover support materials; quantifying odour reduction; identifying the impact use these covers may have on greenhouse gas emissions; devising practical and effective methods for constructing these covers. Results have confirmed that a variety of cover materials are effective in reducing pond odour emissions. Supporting the pond cover appears to extend the cover life expectancy. While greenhouse gas emissions appear to vary according to cover type, the overall significance of these emissions is not yet clear. The impact of permeable pond covers on overall pond performance requires additional research.

Randomised placebo controlled trial of nebulised corticosteroids in acute respiratory syncytial viral bronchiolitis

OBJECTIVE

To evaluate short and long term effects of giving nebulised budesonide early in respiratory syncytial viral (RSV) bronchiolitis.

DESIGN

A multicentre randomised double blind placebo controlled trial.

SUBJECTS

Infants admitted to hospital with their first episode of RSV positive bronchiolitis.

INTERVENTION

Randomisation to receive either 1 mg of nebulised budesonide (Bud) or placebo (Pla) twice daily from admission until 2 weeks after discharge. Follow up was for 12 months.

MAIN OUTCOME MEASURES

Duration of hospital admission, time taken to become symptom free, re-admission rates, general practitioner consultation rates, and use of anti-wheeze medication during follow up.

RESULTS

161 infants were studied. Both arms were similar with respect to initial clinical severity, age, sex, socioeconomic class, and tobacco exposure. Median time from first nebulisation to discharge: Bud and Pla, 2 days. Median number of days for 50% of infants to be symptom free for 48 hours: Bud, 10 days; Pla, 12 days. Respiratory re-admission rates in the 12 month follow up: Bud, 16%; Pla, 18%; median difference (95% confidence interval (CI)), -2 (-14 to 10). Median respiratory related general practitioner attendances: Bud, 4.0; Pla, 4.5; median difference (95% CI), -1 (-2 to 0). Percentage of infants receiving at least one prescription for anti-wheeze medication during follow up, corticosteroids: Bud, 50%; Pla, 60%; difference (95% CI), -10 (-26 to 6); bronchodilators: Bud, 60%; Pla, 67%; difference (95% CI), -7 (-22 to 8).

CONCLUSIONS

There are no short or long term clinical benefits from the administration of nebulised corticosteroids in the acute phase of RSV bronchiolitis.

Neutrophils, Helicobacter pylori, and nonsteroidal anti-inflammatory drug ulcers

BACKGROUND & AIMS

Gastric injury by nonsteroidal anti-inflammatory drugs (NSAIDs) is minimal in neutropenic animals. This study examined peptic ulcer development in the presence or absence of gastric neutrophils in patients requiring long-term use of NSAIDs.

METHODS

Gastric histology, neutrophils, and Helicobacter pylori were assessed in 120 patients randomized to receive placebo or 20 or 40 mg famotidine twice daily as prophylaxis against NSAID-related ulcers and who underwent endoscopy at 0, 4, 12, and 24 weeks.

RESULTS

In 43 patients without gastric neutrophils, ulcers developed in 1 of 14 (7.7%) taking placebo, 2 of 16 (12.5%) taking 20 mg famotidine, and none of 13 taking 40 mg famotidine. However, in 77 patients with neutrophils, ulcers developed in 13 of 28 (47. 4%) taking placebo (P < 0.001), 3 of 26 (12.6%) taking 20 mg famotidine, and 3 of 23 (13%) taking 40 mg famotidine. Eight of 46 patients (17%) without H. pylori had neutrophils compared with 69 of 74 (93%) with both H. pylori and neutrophils (P < 0.001).

CONCLUSIONS

Gastric neutrophils increase the incidence of ulceration in long-term NSAID users. Because neutrophils exist with H. pylori, eradicating this infection might prevent NSAID-related peptic ulcers.

Protection of human gastric mucosa against aspirin-enteric coating or dose reduction?

BACKGROUND

Aspirin is widely used for cardiovascular prophylaxis.

AIM

To compare the effectiveness of two widely-used strategies-dose reduction and enteric coating-for the minimization of gastric mucosal injury or toxicity.

METHODS

Twelve healthy volunteers were studied. On four separate occasions each received, under blinded conditions, five daily doses of plain aspirin 300 mg, plain aspirin 75 mg, enteric-coated aspirin 300 mg or placebo. Ex vivo prostaglandin E2 synthesis was stimulated by the vortex mixing of gastric mucosal biopsies in Tris saline and measured by radioimmunoassay. Mucosal injury was quantified both by counting erosions and with a visual analogue scale.

RESULTS

All three preparations reduced prostaglandin E2 synthesis by day five, by (median) 84% for plain aspirin 300 mg, by 80% for enteric coated aspirin 300 mg and by 63% for plain aspirin 75 mg. There was little mucosal injury prior to the start of each dose and period and no significant change with placebo. Plain aspirin caused a dose-dependent mucosal injury, with two (median, IQR 0-7) gastric erosions after five days of plain aspirin 75 mg, and 18 (2-26) after five days of plain aspirin 300 mg. With enteric-coated aspirin 300 mg there were 0 (0-1) gastric erosions (P = 0.003 compared to plain aspirin 300 mg P = 0.11, compared to plain aspirin 75 mg).

CONCLUSION

Enteric coated aspirin reduces acute gastric mucosal injury to placebo levels, despite its inhibition of prostaglandin synthesis. Enteric coating is an appropriate strategy for the prevention of gastric mucosal damage induced by low-dose aspirin, which warrants systematic clinical evaluation.

Steroid contents of and steroidogenesis in vitro by the developing gonad and mesonephros around sexual differentiation in fetal sheep

The aim of the present study was to establish whether the steroids, progesterone, androstenedione, testosterone and oestradiol, were present in the mesonephric-gonadal complex of female and male sheep fetuses around sexual differentiation (that is, from day 28 to day 45 of gestation, with sexual differentiation occurring at approximately day 32). A second aim was to test whether the mesonephric-gonadal complex, mesonephros (days 35-45 only) and gonad (days 35-45 only) were capable of steroid synthesis in vitro. The steroid contents in the mesonephric-gonadal complex were not detectable before sexual differentiation. However, from day 35 of gestation onwards, the mesonephric-ovarian complex contained mainly oestradiol and the mesonephric-testicular complex contained mainly testosterone: from day 35 until day 45 the increase in content of these two steroids exceeded the increase in the mass of tissue by more than fivefold. From day 40 to day 45 of gestation, the contents of the other steroids in the pathways to oestradiol increased progressively in both sexes but more in parallel with the increase in tissue mass. In contrast to the steroid contents in the tissue at recovery, the mesonephric-gonadal tissue from both sexes in tissue culture was able to synthesize most steroids before and after sexual differentiation and also to metabolise supplementary androstenedione to oestradiol. These findings suggest that many, if not all, of the steroidogenic enzymes in the pathway from cholesterol to oestradiol are present before sexual differentiation. Most of the aforementioned steroids were present in detectable amounts in isolated mesonephros and gonad of both sexes after sexual differentiation. Moreover, for both the isolated mesonephros and gonad, there were increases in the mean contents of most steroids after culture relative to the contents in the tissues at recovery. These data suggest that the mesonephros, as well as the gonad, in both sexes is capable of synthesizing steroid. It is concluded that, in the sheep fetus, the female and male gonads are steroidogenically active after sexual differentiation, that the steroidogenic enzymes develop before sexual differentiation, and that the mesonephros is a site of steroid synthesis.

Non-rabies Lyssavirus human encephalitis from fruit bats: Australian bat Lyssavirus (pteropid Lyssavirus) infection

A 39-year-old woman died of encephalitis a few weeks after being scratched by fruit bats. Autopsy disclosed meningoencephalomyelitis, and revealed neuronal intracytoplasmic inclusions which had similarities to Negri bodies of rabies. Laboratory investigations detected a Lyssavirus type previously identified only in fruit bats. This appears to be the first human case of encephalitis due to this Lyssavirus type.

The association of soft-tissue rheumatism and hypermobility

Soft-tissue rheumatism (STR--tendinitis, bursitis, fasciitis and fibromyalgia) accounts for up to 25% of referrals to rheumatologists. The estimated prevalence of generalized hypermobility in the adult population is 5-15%. There have previously been suggestions that hypermobile individuals may be predisposed to soft-tissue trauma and subsequent musculoskeletal pain. This study was designed to examine the mobility status and physical activity level in consecutive rheumatology clinic attendees with a primary diagnosis of STR. Of 82 patients up to age 70 yr with STR, 29 (35%) met criteria for generalized hypermobility. Hypermobile compared to non-hypermobile individuals reported significantly more previous episodes of STR (90% vs 51%, P < 0.01), and more recurrent episodes of STR at a single site (69% vs 38%, P < 0.001). Although we were unable to show any difference in the time spent carrying out physical activity between the two groups, the hypermobile patients were performing significantly more repetitive activities. When specific anatomical sites of STR were analysed, small joints (elbows, hands and feet) currently affected with STR were more likely to show localized hypermobility than if those joints were asymptomatic. These findings suggest that hypermobility may be a factor in the development of STR. Repetitive activity may be a contributing factor towards STR in some hypermobile individuals.

Effect of sucralfate on aspirin induced mucosal injury and impaired haemostasis in humans

BACKGROUND

Sucralfate does not have potent anti-ulcerogenic actions in users of non-steroidal anti-inflammatory drugs (NSAIDs). However, sucralfate may influence intragastric haemostasis favourably.

AIM

To investigate separately the effects of sucralfate on acute gastric and duodenal injury and on changes in intragastric bleeding induced by aspirin.

METHOD

On three occasions, 24 healthy volunteers received three days' treatment with aspirin 900 mg twice daily together with placebo, sucralfate 2 g twice daily or sucralfate 1 g four times daily. Injury was assessed endoscopically and bleeding by spontaneous and biopsy induced bleeding intragastric washings. Ex vivo prostaglandin E2 (PGE2) synthesis and serum thromboxane were measured by using radioimmunoassay.

RESULTS

Aspirin significantly inhibited ex vivo gastric mucosal PGE2 synthesis, reduced serum thromboxane, caused gastric erosions, and increased spontaneous and biopsy induced bleeding. Sucralfate had no significant effects on endoscopic injury but sucralfate 1 g four times daily significantly reduced spontaneous and biopsy induced bleeding. Similar trends were seen with sucralfate 2 g twice daily but the results were less consistent.

CONCLUSION

Sucralfate does not affect aspirin induced acute gastric mucosal injury but reduces aspirin associated intragastric bleeding.

Famotidine for healing and maintenance in nonsteroidal anti-inflammatory drug-associated gastroduodenal ulceration

BACKGROUND & AIMS

Nonsteroidal anti-inflammatory drugs (NSAIDs) are strongly associated with gastroduodenal ulceration. How to manage patients with NSAID-associated ulcers is a common clinical dilemma. High-dose famotidine in the healing and maintenance of NSAID-associated gastroduodenal ulceration was therefore evaluated.

METHODS

One hundred four patients with rheumatoid or osteoarthritis who had gastroduodenal ulceration received famotidine, 40 mg twice daily. Sixteen patients stopped and 88 continued their NSAID treatment. Ulcer healing was assessed endoscopically at 4 and 12 weeks. Seventy-eight NSAID users with healed ulcers were then randomized to receive 40 mg twice daily famotidine or placebo and underwent endoscopy at 4, 12, and 24 weeks.

RESULTS

Cumulative ulcer healing rates at 12 weeks were 89.0% (95% confidence interval [CI], 82.3%-95.7%) for patients who continued NSAID treatment and 100% (95% CI, 82.9%-100.0%) for those who stopped. The subsequent estimated cumulative gastroduodenal ulcer relapse over 6 months for NSAID users who took placebo was 53.5% (95% CI, 36.6%-70.3%). This was reduced to 26.0% (12.1%-39.9%) in patients taking famotidine (P = 0.011).

CONCLUSIONS

High-dose famotidine is effective ulcer healing therapy in patients who stop or continue NSAID treatment and significantly reduced the cumulative incidence of gastroduodenal ulcer recurrence compared with placebo when given as maintenance therapy.