Prioritize effluent quality, operational costs or global warming? - Using predictive control of wastewater aeration for flexible management of objectives in WRRFs

This study presents a general model predictive control (MPC) algorithm for optimizing wastewater aeration in Water Resource Recovery Facilities (WRRF) under different management objectives. The flexibility of the MPC is demonstrated by controlling a WRRF under four management objectives, aiming at minimizing: (A) effluent concentrations, (B) electricity consumption, (C) total operations costs (sum electricity costs and discharge effluent tax) or (D) global warming potential (direct and indirect nitrous oxide emissions, and indirect from electricity production) . The MPC is tested with data from the alternating WRRF in Nørre Snede (Denmark) and from the Danish electricity grid. Results showed how the four control objectives resulted in important differences in aeration patterns and in the concentration dynamics over a day. Controls B and C showed similarities when looking at total costs, while similarities in global warming potential for controls A and D suggest that improving effluent quality also reduced greenhouse gasses emissions. The MPC flexibility in handling different objectives is shown by using a combined objective function, optimizing both cost and greenhouse emissions. This shows the trade-off between the two objectives, enabling the calculation of marginal costs and thus allowing WRRF operators to carefully evaluate prioritization of management objectives. The long-term MPC performance is evaluated over 51 days covering seasonal and inter-weekly variations. On a daily basis, control A was 9-30% cheaper on average compared to controls A, D and to the current rule-based control. Similarly, control D resulted on average in 35-43% lower greenhouse gasses daily emission compared to the other controls. Difference between control performance increased for days with greater inter-diurnal variations in electricity price or greenhouse emissions from electricity production, i.e. when MPC has greater possibilities for exploiting input variations. The flexibility of the proposed MPC can easily accommodate for additional control objectives, allowing WRRF operators to quickly adapt the plant operation to new management objectives and to face new performance requirements.

Integrated model predictive control of water resource recovery facilities and sewer systems in a smart grid: example of full-scale implementation in Kolding

An integrated model predictive control (MPC) strategy to control the power consumption and the effluent quality of a water resource recovery facility (WRRF) by utilizing the storage capacity from the sewer system was implemented and put into operation for a 7-day trial period. This price-based MPC reacted to electricity prices and forecasted pollutant loads 24 hours ahead. The large storage capacity available in the sewer system directly upstream from the plant was used to control the incoming loads and, indirectly, the power consumption of the WRRF during dry weather operations. The MPC balances electricity costs and treatment quality based on linear dynamical models and predictions of storage capacity and effluent concentrations. This article first shows the modelling results involved in the design of this MPC. Secondly, results from full-scale MPC operation of the WRRF are shown. The monetary savings of the MPC strategy for the specific plant were quantified around approximately 200 DKK per day when fully exploiting the allowed storage capacity. The developed MPC strategy provides a new option for linking WRRFs to smart grid electricity systems.

T Cell- and Monocyte-Specific RNA-Sequencing Analysis in Septic and Nonseptic Critically Ill Patients and in Patients with Cancer

Sepsis is characterized as life-threatening organ dysfunction caused by a dysregulated host immune response to infection. The purpose of this investigation was to determine the differential effect of sepsis on innate versus adaptive immunity, in humans, by examining RNA expression in specific immune cell subsets, including monocytes/macrophages and CD4 and CD8 T cells. A second aim was to determine immunosuppressive mechanisms operative in sepsis that might be amenable to immunotherapy. Finally, we examined RNA expression in peripheral cells from critically ill nonseptic patients and from cancer patients to compare the unique immune response in these disorders with that occurring in sepsis. Monocytes, CD4 T cells, and CD8 T cells from septic patients, critically ill nonseptic patients, patients with metastatic colon cancer, and healthy controls were analyzed by RNA sequencing. Sepsis induced a marked phenotypic shift toward downregulation of multiple immune response pathways in monocytes suggesting that impaired innate immunity may be fundamental to the immunosuppression that characterizes the disorder. In the sepsis cohort, there was a much more pronounced effect on gene transcription in CD4 T cells than in CD8 T cells. Potential mediators of sepsis-induced immunosuppression included Arg-1, SOCS-1, and SOCS-3, which were highly upregulated in multiple cell types. Multiple negative costimulatory molecules, including TIGIT, Lag-3, PD-1, and CTLA-4, were also highly upregulated in sepsis. Although cancer had much more profound effects on gene transcription in CD8 T cells, common immunosuppressive mechanisms were present in all disorders, suggesting that immunoadjuvant therapies that are effective in one disease may also be efficacious in the others.

Shared Molecular Signatures Across Neurodegenerative Diseases and Herpes Virus Infections Highlights Potential Mechanisms for Maladaptive Innate Immune Responses

Growing evidence suggests that peripheral factors to the brain driving neuro-inflammation could affect Alzheimer’s Disease (AD) and Parkinson’s Disease (PD) severity. Herpes simplex virus type 1 (HSV1) infection has been associated with AD while other related viruses, including cytomegalovirus (CMV), Epstein-Bar virus and human herpesvirus 6 (HHV6), are known to infect neurons. Here we compare gene expression profiles between AD or PD patients to those afflicted with herpes viral infections as to discover novel potential neuro-inflammation pathways. We found multiple significant differentially expressed genes (DEGs) shared between AD/PD and viral infections including SESN3 which has a genetic association for increased AD risk. Pathway enrichment analysis revealed viruses shared Oxidative Stress Defense System and LRRK2 pathways with AD and PD, respectively. We further processed our data to identify novel target and drug-repurposing opportunities including anti-inflammatory therapy, immune-modulators and cholinesterase inhibitors which could lead to new therapeutics paradigms for these neurodegenerative diseases.

A systematic approach integrating genetics, computational biology, chemical genomics and gene editing to identify novel targets in the Type I interferon signaling pathway for autoimmune and infectious diseases

The type I interferon (IFN a/b) signaling pathway plays a critical role in microbial host defense, including mediating the interaction between innate and adaptive immunity. A growing body of evidence suggests that IFN is aberrantly regulated in human autoimmune diseases and chronic infections, such as Systematic Lupus Erythematosus, HIV infection and the rare Mendelian diseases, Aicardi-Goutier Syndrome and the Singleton Merton Syndrome (also called “interferonopathies”). This has raised significant interest in exploring the cellular signaling associated with type I IFNs for potential targets for autoimmunity and infectious disease. In this study, we systematically interrogated the type I IFN signaling pathway to identify and validate potential therapeutic targets based on the following workflow: 1. Perform computational biology analysis using genetics, interaction networks and gene expression in human diseases to generate a list of targets that have an association with increased type I IFN. 2. Establish the THP-1 cell-based type I IFNbeta release assay to screen a focused set of target annotated tool compounds. 3. Integrate the inferred targets from the tool compound hits into the in-silico network analysis. 4. Generate a short list of targets (10–20) with high confidence to perform CRISPR analysis in THP-1 cells. 5. Generate a long list of targets (~200) to perform a pooled CRISPR screen using single cell technology and reporter-based flow sorting and enrichment. Here we present validation data on a few representative targets and a summary of the outcomes and learning from this study.

Regional frequency analysis of short duration rainfall extremes using gridded daily rainfall data as co-variate

A regional partial duration series (PDS) model is applied for estimation of intensity duration frequency relationships of extreme rainfalls in Denmark. The model uses generalised least squares regression to relate the PDS parameters to gridded rainfall statistics from a dense network of rain gauges with daily measurements. The Poisson rate is positively correlated to the mean annual precipitation for all durations considered (1 min to 48 hours). The mean intensity can be assumed constant over Denmark for durations up to 1 hour. For durations larger than 1 hour, the mean intensity is significantly correlated to the mean extreme daily precipitation. A Generalised Pareto distribution with a regional constant shape parameter is adopted. Compared to previous regional studies in Denmark, a general increase in extreme rainfall intensity for durations up to 1 hour is found, whereas for larger durations both increases and decreases are seen. A subsample analysis is conducted to evaluate the impacts of non-stationarities in the rainfall data. The regional model includes the non-stationarities as an additional source of uncertainty, together with sampling uncertainty and uncertainty caused by spatial variability.

Biology and Control of Snail Intermediate Host of Schistosoma japonicum in The People's Republic of China

Schistosomiasis caused by Schistosoma japonicum is a severe parasitic disease in The People's Republic of China and imposed considerable burden on human and domestic animal health and socioeconomic development. The significant achievement in schistosomiasis control has been made in last 60years. Oncomelania hupensis as the only intermediate host of S. japonicum plays a key role in disease transmission. The habitat complexity of the snails challenges to effective control. In this review we share the experiences in control and research of O. hupensis.

Identifying climate analogues for precipitation extremes for Denmark based on RCM simulations from the ENSEMBLES database

Climate analogues, also denoted Space-For-Time, may be used to identify regions where the present climatic conditions resemble conditions of a past or future state of another location or region based on robust climate variable statistics in combination with projections of how these statistics change over time. The study focuses on assessing climate analogues for Denmark based on current climate data set (E-OBS) observations as well as the ENSEMBLES database of future climates with the aim of projecting future precipitation extremes. The local present precipitation extremes are assessed by means of intensity-duration-frequency curves for urban drainage design for the relevant locations being France, the Netherlands, Belgium, Germany, the United Kingdom, and Denmark. Based on this approach projected increases of extreme precipitation by 2100 of 9 and 21% are expected for 2 and 10 year return periods, respectively. The results should be interpreted with caution as the best region to represent future conditions for Denmark is the coastal areas of Northern France, for which only little information is available with respect to present precipitation extremes.

An overview of freshwater snails in Asia with main focus on Vietnam

Freshwater snails have received much attention for their role as intermediate hosts for trematodes causing disease in people and animals such as schistosomiasis and various food-borne trematodes. While effective medical treatment exists for some of these diseases there is need for preventive measures to reduce transmission, e.g. control of intermediate hosts because transmission patterns are often complicated due to presence of reservoir final hosts. In order to implement control measures against the intermediate host snails with minimal impact on the freshwater ecosystems and their biodiversity, a profound knowledge on transmission patterns of the trematodes is required and this is partly related to distribution, habitat preferences, and seasonal variation in density of the intermediate host species. Identification of snail species can be problematic on the basis of morphological and anatomical characters alone as some species show morphological plasticity and similarly morphological differentiation of cercariae found in snails may be difficult and this could lead to biased perceptions of intermediate host spectra and transmission patterns. In this paper, we give an overview of the snail families and their medical and veterinary importance in Asia but with main focus on Vietnam.

Resolving pathobiological mechanisms relating to Huntington disease: gait, balance, and involuntary movements in mice with targeted ablation of striatal D1 dopamine receptor cells

Progressive cell loss is observed in the striatum, cerebral cortex, thalamus, hypothalamus, subthalamic nucleus and hippocampus in Huntington disease. In the striatum, dopamine-responsive medium spiny neurons are preferentially lost. Clinical features include involuntary movements, gait and orofacial impairments in addition to cognitive deficits and psychosis, anxiety and mood disorders. We utilized the Cre-LoxP system to generate mutant mice with selective postnatal ablation of D1 dopamine receptor-expressing striatal neurons to determine which elements of the complex Huntington disease phenotype relate to loss of this neuronal subpopulation. Mutant mice had reduced body weight, locomotor slowing, reduced rearing, ataxia, a short stride length wide-based erratic gait, impairment in orofacial movements and displayed haloperidol-suppressible tic-like movements. The mutation was associated with an anxiolytic profile. Mutant mice had significant striatal-specific atrophy and astrogliosis. D1-expressing cell number was reduced throughout the rostrocaudal extent of the dorsal striatum consistent with partial destruction of the striatonigral pathway. Additional striatal changes included up-regulated D2 and enkephalin mRNA, and an increased density of D2 and preproenkephalin-expressing projection neurons, and striatal neuropeptide Y and cholinergic interneurons. These data suggest that striatal D1-cell-ablation alone may account for the involuntary movements and locomotor, balance and orofacial deficits seen not only in HD but also in HD phenocopy syndromes with striatal atrophy. Therapeutic strategies would therefore need to target striatal D1 cells to ameliorate deficits especially when the clinical presentation is dominated by a bradykinetic/ataxic phenotype with involuntary movements.

Impacts of climate change on rainfall extremes and urban drainage systems: a review

A review is made of current methods for assessing future changes in urban rainfall extremes and their effects on urban drainage systems, due to anthropogenic-induced climate change. The review concludes that in spite of significant advances there are still many limitations in our understanding of how to describe precipitation patterns in a changing climate in order to design and operate urban drainage infrastructure. Climate change may well be the driver that ensures that changes in urban drainage paradigms are identified and suitable solutions implemented. Design and optimization of urban drainage infrastructure considering climate change impacts and co-optimizing these with other objectives will become ever more important to keep our cities habitable into the future.

Comparative uncertainty analysis of copper loads in stormwater systems using GLUE and grey-box modeling

In this paper two attempts to assess the uncertainty involved with model predictions of copper loads from stormwater systems are made. In the first attempt, the GLUE methodology is applied to derive model parameter sets that result in model outputs encompassing a significant number of the measurements. In the second attempt the conceptual model is reformulated to a grey-box model followed by parameter estimation. Given data from an extensive measurement campaign, the two methods suggest that the output of the stormwater pollution model is associated with significant uncertainty. With the proposed model and input data, the GLUE analysis show that the total sampled copper mass can be predicted within a range of +/-50% of the median value (385 g), whereas the grey-box analysis showed a prediction uncertainty of less than +/-30%. Future work will clarify the pros and cons of the two methods and furthermore explore to what extent the estimation can be improved by modifying the underlying accumulation-washout model.

The schistosome intermediate host, Bulinus nyassanus, is a 'preferred' food for the cichlid fish, Trematocranus placodon, at Cape Maclear, Lake Malawi

Over the last decade, transmission of the schistosome parasites of humans has increased in parts of Lake Malawi, possibly because over-fishing has led to a decline in the numbers of molluscivorous fish. The stomach contents of 51 wild-caught Trematocranus placodon from the Cape Maclear area of Lake Malawi have now been investigated and compared with the field abundance of snail species at two sites, close to where the fish were caught. The snails found in the fish stomachs were identified to genus or species on the basis of their shell fragments and/or opercula. The sizes of the prosobranchs consumed by the T. placodon were determined from their operculum sizes whereas the Bulinus nyassanus ingested by the fish were categorized as small (<4 mm) or large (> or =4 mm) on the basis of their shell fragments. The proportion of the Bu. nyassanus ingested that were categorized as large increased with fish size. Furthermore, the relative abundance of Bu. nyassanus in the guts of the fish was considerably higher than in the field, indicating that the T. placodon had a 'preference' for Bu. nyassanus over the Melanoides species that dominated the snail fauna. Small specimens of Bellamya species were also consumed in a greater proportion than found in field.

Genetic polymorphisms in the genes encoding human interleukin-7 receptor-alpha: prognostic significance in allogeneic stem cell transplantation

Interleukin-7 (IL-7) is essential for T-cell development in the thymus and for the maintenance of peripheral T cells. IL-7 signals through IL-7R, that consists of the gammac-chain and an alpha-chain. Sequencing of IL-7Ralpha has revealed the existence of four single nucleotide polymorphisms (SNPs) (+510C/T, +1237 A/G, 2087T/C and +3110A/G), which all give rise to amino-acid substitutions. The aim of the present investigation was to evaluate the significance of IL-7Ralpha SNPs for the outcome in allogeneic stem cell transplantation (SCT). IL-7Ralpha polymorphisms were determined in 195 recipient and donor pairs from either matched sibling donors or matched unrelated donors (MUD). Genotyping of 173 normal controls was performed in parallel. In MUD transplants, the +1237 genotype of the donor was associated with survival after SCT, the mortality being highest and intermediate for the GG and AG genotypes, respectively (P = 0.023). This pattern was more pronounced with respect to treatment-related mortality (P = 0.003), while IL-7Ralpha genotypes were unrelated to the risk of relapse of leukaemia. The IL-7Ralpha +1237 genotype of the recipient and the genotypes of the other three polymorphisms, were not significantly associated with the outcome of SCT. These findings suggest that the IL-7Ralpha polymorphisms may be of importance for treatment-related mortality after SCT.

Insights to the minimal model of insulin secretion through a mean-field beta cell model

The present work introduces an extension of the original minimal model of second phase insulin secretion during the intravenous glucose tolerance test (IVGTT), which can provide both physiological and mathematical insights to the minimal model. The extension is named the mean-field beta cell model since it returns the average response of a large number of nonlinear secretory entities. Several secretion models have been proposed for the IVGTT, and we shall identify two fundamentally different theoretical features of these models. Both features can play a central role during the IVGTT, including the one presented in the mean-field beta cell model.

Epidemiology and morbidity of Schistosoma mansoni infection in a fishing community along Lake Albert in Uganda

Schistosoma mansoni infection, associated morbidity and symptoms were studied in Piida fishing community at Butiaba, along Lake Albert, Uganda, from November 1996 to January 1997. The study revealed that S. mansoni is highly endemic with an overall prevalence of 72%, a mean intensity of 419.4 eggs per gram (epg) faeces (geometric mean for positives only), with 37.8% of males and 33.0% of females excreting over 1000 epg. Prevalence and intensity peaked in the 10-14 year old age group and decreased with increasing age. Females were less heavily infected than males. Differences were also shown between tribes. Diarrhoea and abdominal pain were commonly reported in Piida. However, no clear-cut correlation between intensity of S. mansoni infection and these conditions could be demonstrated, indicating that retrospective questionnaires concerning S. mansoni related-symptomatology are of limited value. Organomegaly, as assessed by ultrasonography, was frequent and hepatomegaly was associated with heavy S. mansoni infection. No correlation was demonstrated between splenomegaly and infection. This study emphasizes that schistosomiasis mansoni is a major public health problem in Piida fishing community and presumably also in many similar fishing communities. These observations call for immediate intervention and can help in planning long-term strategies for sustainable morbidity control.

Comparison of schistosome transmission in a single- and a double-cropped area in the rice irrigation scheme, 'Office du Niger', Mali

Rice is becoming increasingly important as a staple food in West Africa and there is a need to increase production to meet the demand and one way to achieve this is to harvest two annual crops. It is possible that such intensified irrigation could affect transmission of schistosomes and this study attempts to compare schistosome transmission in single and double-cropped areas of an irrigation scheme, 'Office du Niger', in Mali. Double cropping has been practised for some years in the Niono area while in the Kolongotomo area still only a single crop is grown. Parasitological surveys conducted in 10 villages (5 from each of these 2 areas) showed that Schistosoma haematobium was less prevalent in the area with single cropping than in the area with double cropping. In order to compare transmission patterns between the two areas, all human-water contact sites around four villages (two from each area) were identified and included in transmission studies. From August 1996 to June 1997, eight surveys were conducted, at intervals of approximately 45 days, in each of these sites to record density of the intermediate hosts, density of infected snails, environmental factors (especially density of aquatic macrophytes), and frequency of human-water contacts. Although the data provide useful information on transmission patterns in Niono and Kolongotomo areas, they fail to demonstrate clear-cut differences in snail population dynamics and transmission patterns between the two areas. A key element in snail habitats in both areas is the abundance of aquatic macrophytes, especially the submerged species. Snail control using environmental modification should focus on controlling these plants in human-water contact sites.

Efficacy and side effects of praziquantel treatment in a highly endemicSchistosoma mansoni focus at Lake Albert, Uganda

The aim of the study was to assess the efficacy and side effects following single and repeated (6 weeks apart) praziquantel treatment (40 mg/kg) in a Schistosoma mansoni-endemic focus with long-standing transmission at Lake Albert in Uganda between December 1996 and January 1997. The results were based on 482 individuals, randomly representing all age and both gender groups. The cure rate following the first and second treatments was 41.9% and 69.1%, respectively. The cure rate was higher in adults than in children, irrespective of intensity of infection. In addition, the cure rate declined markedly with increasing intensity of infection. The reduction in intensity of infection was marked, being 97.7% and 99.6% after the first and second treatments, respectively. A pre- and post-treatment symptom questionnaire revealed a broad range of side effects, including abdominal pain and diarrhoea. However, no serious or long-lasting complications affecting compliance were observed. The marked reductions in faecal egg excretion and the acceptable level of side effects point to a single praziquantel treatment (40mg/kg) as the strategy of choice in such a highly endemic S. mansoni focus.

Observations on the swarming and mating behaviour of Anopheles funestus from southern Mozambique

BACKGROUND

Control of malaria by the release of genetically modified mosquitoes refractory to transmission is now becoming a possibility. In many areas of Africa, Anopheles gambiae is found together with an equally important vector, An. funestus. Given their sympatry and the likelihood of a similar mating period some aspects of the mating behaviour of An. gambiae s.l. and An. funestus are likely to differ. We therefore attempted to characterise the swarming behaviour of An. funestus and to determine if any aspects of the observed behaviour differed from that recorded for the M form of An. gambiae from São Tomé.

METHODS

In March - May 2002 the swarming, mating, house exiting and resting behaviour of Anopheles funestus was studied by direct observation in Mozambique. Swarming males and insects in copula were collected by sweep net. Wing lengths of males collected resting, exiting houses, swarming and mating were measured and the wingbeat frequency distribution of individual insects, in free flight confined inside netting covered paper cups, was also determined.

RESULTS

Mono-specific swarms occurred at sunset in relatively open areas close to houses used for resting. Mating pairs were seen 11 +/- 3.7 min after the start of swarming. The number of total pairs observed being inversely proportional to the time difference between the start of swarming and the first pairing. The great majority of females mated before feeding. Male or female size did not appear to affect mating success or other behaviours. During the study, ambient temperatures decreased and female, but not male, wing size increased. At 516 Hz, the flight tone of female An. funestus was similar to the 497 Hz of the local An. gambiae. Males dispersed if light or dark artificial horizontal markers were placed underneath naturally occurring swarms.

CONCLUSION

Differential response to markers would be sufficient for swarming in An. funestus and An. gambiae s.l. to occur in distinct sites.

Data assimilation in the decision support system rodos

Model predictions for a rapid assessment and prognosis of possible radiological consequences after an accidental release of radionuclides play an important role in nuclear emergency management. Radiological observations, e.g. dose rate measurements, can be used to improve such model predictions. The process of combining model predictions and observations, usually referred to as data assimilation, is described in this article within the framework of the real time on-line decision support system (RODOS) for off-site nuclear emergency management in Europe. Data assimilation capabilities, based on Kalman filters, are under development for several modules of the RODOS system, including the atmospheric dispersion, deposition, food chain and hydrological models. The use of such a generic data assimilation methodology enables the propagation of uncertainties throughout the various modules of the system. This would in turn provide decision makers with uncertainty estimates taking into account both model and observation errors. This paper describes the methodology employed as well as results of some preliminary studies based on simulated data.

The swarming and mating behaviour of Anopheles gambiae s.s. (Diptera: Culicidae) from São Tomé Island

The swarming and mating behaviours of the forest cytoform of Anopheles gambiae s.s. were investigated on 194 evenings and 14 mornings between April 1997 and November 1999 in a peri-urban area of the island of São Tomé, West Africa. Males swarmed 2-3 m above markers of horizontal contrast such as those formed between grass areas and footpaths, or bushes. Evening swarms started 2 min before sunset in sheltered sites and a minute or two later in exposed ones. It took approximately 5 mins from the arrival of the first male for the swarm to reach estimated maximum numbers. Mating pairs were first seen 7 min after the start of swarming. Maximum numbers of pairs in copula were observed 8 min later. Up to 270 pairings were seen in the 20 min period before darkness. Removal of males had no effect on the number of females arriving at the swarm. Males were attracted to sounds that approximated the female flight tone but not to filter paper samples of squashed virgin females swung through the swarm. A much-reduced amount of swarming and a single mating were recorded at dawn. The same locations for swarming were used at different times and at different heights by ants, Culicoides sp. and Culex quinquefasciatus.

[General practitioners' knowledge of and attitude to assessment and treatment of women with urinary incontinence. A questionnaire among general practitioners in Denmark]

INTRODUCTION

Urinary incontinence is a common problem for adult women, and the need for assessment and treatment of incontinence is expected to increase in the future. The aim of this study was to elucidate the general practitioners' (GPs) knowledge about and attitude to women with urinary incontinence.

METHODS

A questionnaire was posted to 1700 randomly selected GPs in 1998 and 1999.

RESULTS

A total of 1071 (63%) GPs responded at least once. Five hundred (29%) returned the questionnaire both years. About 50% expressed a positive interest in the management of urinary incontinence. Only 24% felt that their knowledge was sufficient to manage incontinence. About 50% and 66% of the GPs would probably refer a patient with stress incontinence or urge incontinence to a specialist. The GPs' proposals for assessment and treatment were mainly consistent with good clinical practice. There were only minor changes in knowledge and attitude from 1998 to 1999.

DISCUSSION

GPs' interest in urinary incontinence is moderate and management is characterised by a high referral rate to a specialist. Most GPs. consider their knowledge to be inadequate. There is need for education to ensure sufficient knowledge and to change the attitude, so that first-line assessment and treatment of urinary incontinence is carried out in general practice.

Sensory changes during the ovulatory phase of the menstrual cycle in healthy women

This study compared the pain sensitivity in healthy women at the abdomen and lower back (presumed referral areas of menstrual pain), thigh and arm (control areas), in the menstrual, ovulatory, luteal and premenstrual phases of confirmed ovulatory cycles, with that of males. The pressure pain threshold (PPT) and pinch pain threshold (PiPT) was determined by an electronic pressure algometer, heat pain threshold (HPT) by a contact thermode and tactile threshold (TT) with von Frey hairs. The abdominal PPT was significantly lower in females in all menstrual phases as compared to the control sites ( p<0.0007). The abdominal and lower back HPT was significantly lower in females in all menstrual phases compared with control areas, and to the sites in males ( p<0.002). The TT was significantly reduced in females compared with males ( p< 0.013). There was no difference in the PiPT between females and males. In males, the HPT, PPT and TT were not different within any site. During the ovulatory phase, the HPT was significantly reduced at the abdomen and the PPT at the back compared with the menstrual, luteal and premenstrual phases (p<0.0002). There were no within-menstrual phase variations in the PiPT and TT at any site, or for the HPT and PPT at the control areas. The reduced thresholds in menstruating women may be due to the presence of latent uterine algogenic stimuli, and the increased levels of oestrogen and leuteinizing hormone at ovulation may enhance nociception by acting both at the peripheral and central level, resulting in the hypersensitivity changes at the abdomen and lower back areas.

Bulinus nyassanus is an intermediate host for Schistosoma haematobium in Lake Malawi

At Cape Maclear on the Nankumba Peninsula, close to the southern end of Lake Malawi, Schistosoma haematobium is highly prevalent in the local people and many tourists become infected with this parasite each year. A 'Bilharzia Control Programme' was initiated in this area in August 1998, as a development collaboration between the Government of Malawi, the Danish Agency for Development Assistance (Danida), and the Danish Bilharziasis Laboratory. Although Bulinus globosus is a known host for S. haematobium, B. nyassanus has not previously been incriminated as an intermediate host. However, schistosome-infected B. nyassanus were discovered in surveys to identify transmission sites on the peninsula. Experimental infections of wild-caught B. nyassanus with S. haematobium proved successful and S. haematobium eggs were found in hamsters experimentally exposed to cercariae retrieved from schistosome-infected, field-collected B. nyassanus. These are remarkable observations since, although there are very few reports of diploid members of this species group being experimentally infected with S. haematobium, B. nyassanus is a diploid member (2n = 36) of the truncatus/tropicus group. Bulinus nyassanus is probably responsible for transmission in Lake Malawi, along rather exposed shorelines, devoid of aquatic macrophytes, with a substrate of sand or gravel.

Drug prescribing among Danish children: a population-based study

OBJECTIVES

To characterise the pattern of drug prescribing in Danish children below 19 years of age.

METHODS

We used the Odense Pharmacoepidemiologic Database to identify all individual prescriptions for 0- to 19-year-olds in the County of Funen, Denmark, in 1998. The drug consumption was analysed by the defined daily dose methods and anatomical chemical classification system, using analytical templates for individual-based drug utilisation statistics.

RESULTS

Of the examined population, 52.6% had one or more prescriptions issued. Overall, 10% of the children accounted for 67.5% of drug prescriptions. Approximately 40% of the children had a prescription issued before they were 1 year old. In 1- to 2-year-olds, 85% received a prescription. Thereafter, the 1-year prevalence of drug use declined to 40%. The total drug consumption was similar between boys and girls until the early teens; thereafter the girls had a prescription issued twice as often as boys. In all age groups, respiratory drugs dominated and drugs used in dermatology was the second largest group. The third largest group was systemic anti-infective agents for children below 12 years of age, whereas it was psychotropic drugs among the oldest children.

CONCLUSION

There is the same skewness of drug consumption among Danish children as among Danish adults, but the types of medication differ. Drug use is most extensive among children below 2 years but drug prescribing was considerable in all age groups.

Antibacterial properties of human amnion and chorion in vitro

OBJECTIVE

The purpose of the present study was to explore the direct effects of amnion and chorion on bacterial growth in vitro including the antibacterial spectrum. Chorioamniotic membranes were obtained under sterile conditions from 13 healthy women undergoing elective cesarean section at term. Likewise, chorioamniotic membranes were obtained from 10 healthy women with spontaneous vaginal delivery at term. Five strains of Hemolytic streptococci group B (GBS) were tested and one clinical isolate of the following species or bacterial groups: Hemolytic streptococcus group A, Staphylococcus aureus, Staphylococcus saprophyticus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter calcoaceticus and Lactobacillus species. Bacteriological media included (1) blood-agar medium; (2) a transparent agar medium for submerged cultures; and (3) a nutrient broth medium.

RESULTS

An inhibitory effect of fetal membranes against a range of bacteria was found. Consistent results were obtained in experiments with cultures on agar and cultures suspended in agar (membranes from eight women in both studies). In experiments with liquid cultures (seven women) only chorion showed a marginal inhibitory effect. All strains were inhibited, but the most pronounced inhibition was obtained for streptococcus group A, S. aureus and S. saprophyticus by both chorion and amnion.

CONCLUSION

This study demonstrated an inhibitory effect of the fetal membranes on a diverse panel of bacteria

Fluvoxamine inhibits the CYP2C9 catalyzed biotransformation of tolbutamide

OBJECTIVE

Our objective was to examine the interaction between fluvoxamine and tolbutamide to confirm that fluvoxamine inhibits CYP2C9.

METHODS

The study was carried out as an open, randomized, crossover design with 14 healthy participants. In period A, all volunteers took 500 mg of tolbutamide orally. In period B, the volunteers were randomly assigned to one of two groups. Each group took either 150 mg or 75 mg of fluvoxamine a day for 5 days (day -3 to day 2). The groups then took 500 mg of tolbutamide as a single dose (day 0). In both periods, blood and urine were sampled at regular intervals. Plasma was analyzed for tolbutamide, and urine was analyzed for tolbutamide and its two metabolites, 4-hydroxytolbutamide and carboxytolbutamide by means of HPLC.

RESULTS

During treatment with fluvoxamine, there was a statistically significant decrease in the median of the total clearance of tolbutamide, from 845 mL/h to 688 mL/h, among the volunteers who received 75 mg/d. There was a reduction that reached borderline statistical significance in the group that received 150 mg/d of tolbutamide. The clearance by means of 4-hydroxytolbutamide and carboxytolbutamide was significantly reduced in both groups (ie, from 901 mL/h to 318 mL/h in the group that received 150 mg of tolbutamide per day and from 723 mL/h to 457 mL/h in the group that received 75 mg of tolbutamide per day). Thus there was a tendency toward a more pronounced inhibition of the 4-hydroxylation during treatment with 150 mg/d of fluvoxamine compared with 75 mg/d, but the difference was not statistically significant.

CONCLUSION

Fluvoxamine is a moderate inhibitor of CYP2C9 in vivo.

[Takayasu's arteritis. A rare differential diagnosis in fever of unknown origin]

We report a case of Takayasu's arteritis as a cause of fever of unknown origin in a woman from Somalia. In patients with fever of unknown origin, it is important to consider the rare differential diagnoses and repeat physical examination despite easy access to high-technological examination methods.

New challenges in schistosomiasis control in Morocco

Cases of schistosomiasis were first detected in 1914. However, there is strong evidence that it was prevailing in the southern part of Morocco long before then. As reported from different African countries, over the last three decades, the development of irrigation has led to the spread of the disease to the north and centre of the country. Thereafter, a national programme of schistosomiasis control was launched by the Ministry of Health in 1983. The programme was based on case detection and treatment, snail control using chemicals, and health education. It has succeeded in reducing the prevalence and intensity of infection to a level low enough to allow an elimination programme to be launched in 1994. The aim is to reach a complete elimination of the disease by the year 2004 in all provinces affected. Though substantial progress was made since the programme started, there is a potential risk of outbreaks in many affected provinces. Therefore, an integrated approach including measures against the intermediate host is needed to reach the goal of elimination. The present paper sheds some light on the features of schistosomiasis in Morocco and presents an evaluation of environmental methods of control of Bulinus truncatus in Tessaout Amont and Akka oasis irrigation schemes. The role of community involvement in planning and implementing environmental measures against the snail intermediate host in modern and traditional irrigation schemes is also discussed.

Evaluation of environmental methods to control snails in an irrigation system in Central Morocco

The Moroccan Ministry of Public Health has launched a programme to eliminate schistosomiasis. One of the components in this process is the control of Bulinus truncatus, the intermediate host snail of Schistosoma haematobium. We evaluated three environmentally safe measures to control B. truncatus in siphon boxes, the main breeding sites for these snails in the Tessaout Amont irrigation system. The first method involved covering the siphon boxes to exclude light and reduce algal growth, the second consisted of increasing the frequency of emptying and cleaning the siphon boxes, and the third method increased water velocity to hinder the establishment of the intermediate hosts. The results showed that covering had a pronounced effect on snail and egg mass density, was accepted by the local community and prevented water contact. Cleaning the siphons three times during the irrigation season led to a reduction in snail density although it was not statistically significant and recolonization was rapid. Increasing water velocity by reducing the dimensions of siphon boxes delayed recolonization, but such a control measure can be applied only in specific situations where it does not pose hydraulic problems. The three interventions were selectively effective against B. truncatus, whereas other snails such as Physa acuta and Lymnaea peregra were hardly affected. Covering, the most promising control measure, could be useful in the Moroccan schistosomiasis eradication programme. However, further investigations are needed to assess its impact on water quality.

Schistosoma haematobium in Morocco: moving from control to elimination

In this article, Hammou Laamrani and colleagues summarize the Moroccan schistosomiasis control programme and discuss the challenges ahead for schistosomiasis elimination. In 1994, a programme was initiated by the Moroccan Ministry of Health to eliminate schistosomiasis from Morocco by the year 2004. In 1997, this objective had been achieved in three out of 20 affected provinces. This article discusses the background and strategies of this programme, as well as the achievements, the problems encountered and the challenges ahead, along with suggestions as to how to reach the goal of elimination of urinary schistosomiasis in Morocco, and possibly elsewhere in Africa.

A prospective study of the discrete fascial defect rectocele repair

BACKGROUND

The aim of this study is to describe the results of the discrete fascial defect rectocele repair with special emphasis on dyspareunia after the operation.

METHODS

Sixty-seven women underwent rectocele repair from October 1997 to January 1999. Repair was limited to reapproximation of discrete defects in the rectovaginal fascia when possible and a small perineorrhaphy. Each patient was evaluated as to whether or not a discrete defect was present and the location of the fascial defect. Outcome measures were complications, recurrent prolapse after 3 months, changes in defecation problems and dyspareunia after the operation.

RESULTS

In 96% (64/67) of the patients a discrete defect was present. Before the operation 40% (27/67) reported problems with evacuation of the rectum and 12% (8/67) dyspareunia or problems with intercourse because of the prolapse. The patients were evaluated 3 months after the operation. Only three patients still complained of evacuation problems and only two patients with prior dyspareunia still had problems, which were cured after a further 3 months. Two patients had de novo dyspareunia but in only one patient was an anatomical defect found.

CONCLUSIONS

The discrete defect rectocele repair offers an anatomical correction of the rectocele, which alleviates the symptoms but, most important, does not give the woman dyspareunia. Long term results of the operation are awaited.