Validation of an obstetric fistula screening questionnaire in rural Nepal: a community-based cross-sectional and nested case-control study with clinical examination.

OBJECTIVE: To validate a symptom-based fistula screening questionnaire and estimate obstetric fistula (OF) prevalence in rural Nepal. DESIGN: Cross-sectional and nested case-control study. SETTING: Sarlahi District, Nepal. POPULATION: Parous, reproductive age women. METHODS: The questionnaire assessed symptoms of vesicovaginal and rectovaginal fistula (VVF and RVF, respectively), stress and urge urinary incontinence (SUI and UUI, respectively), fecal incontinence (FI), and included interviewer observations on the smell and presence of urine and/or stool. All women who screened positive for OF and a randomly selected group of women who screened negative for OF were included in a nested case-control study (one case, four normal controls, and four incontinent controls) and underwent confirmatory clinical examinations. MAIN OUTCOME MEASURES: Clinically confirmed OF, and questionnaire sensitivity (Se) and specificity (Sp). RESULTS: Of the 16 893 women who completed cross-sectional screening, 68 were screened-positive cases. Fifty-five (82%) screened-positive cases, 203 screened-negative normal controls, and 203 screened-incontinent controls participated in the case-control study, which confirmed one case of VVF and one case of both VVF and RVF without any false-negative cases. For VVF, the screening tool demonstrated Se 100% (95% CI 34.2-100.0%), Sp 86.9% (95% CI 83.3-89.9%), and estimated VVF prevalence as 12 per 100 000 (95% CI 3-43); for RVF, it demonstrated Se 100% (95% CI 20.7-100.0), Sp 99.8% (95% CI 98.6-100.0), and estimated RVF prevalence as 6 per 100 000 (95% CI 1-34). CONCLUSIONS: The OF screening questionnaire demonstrated high sensitivity and specificity in this low-prevalence setting. TWEETABLE ABSTRACT: Community-based obstetric fistula screening tool validation study, Nepal, n = 16 893: High Se, Sp & feasibility.

First detection of spotted fever group rickettsiae in Ixodes ricinus and Dermacentor reticulatus ticks in the UK.

A preliminary study was conducted to determine the presence of spotted fever rickettsiae in two species of British tick (Ixodes ricinus and Dermacentor reticulatus). The 16S rRNA gene of Rickettsia spp. was detected in 39/401 (9·7%) of ticks tested, including 22/338 (6·5%) I. ricinus and 17/63 (27%) D. reticulatus. Some positive I. ricinus samples showed 100% homology with Rickettsia helvetica (10/22), and most positive D. reticulatus showed 100% homology with R. raoultii (13/17). Five other Rickettsia spp. were detected exhibiting 96-99% homology. Ticks positive for rickettsiae were collected from various hosts and from vegetation from eight counties across Great Britain. The distribution of R. helvetica in various engorged and unfed stages of I. ricinus suggests that R. helvetica is widespread. R. raoultii was found in questing adult D. reticulatus in Wales and England. This is the first evidence of potentially pathogenic spotted fever rickettsiae in British ticks.

[Physicians and scientific research: slight decline of the numbers of physicians with a doctoral degree]. / Artsen en wetenschappelijk onderzoek: lichte teruggang van het aantal gepromoveerde artsen.

OBJECTIVE: To establish whether the number of physicians interested in a career in academia (i.e. research) is declining. DESIGN: Descriptive. METHOD: The researchers analysed the pre- and post-doctoral careers of PhD students at 3 university medical centres (VU Amsterdam, Nijmegen and Maastricht) in 4 separate reference years (1989, 1994, 1999 and 2003), using information from doctoral dissertations and the Dutch medical address book. The researchers recorded the gender of the students and the timing of the doctorate in relation to specialist training, university education and employment, as applicable. RESULTS: The total number of dissertations produced at the 3 medical faculties in the 4 reference years increased gradually by nearly a factor of 2 (1989: 112; 1994: 152; 1999: 198; 2003: 213). In terms of absolute numbers, the number of dissertations authored by physicians increased from 1989 to 1994 and again in 1999 (64, 90 and 105), but decreased slightly in 2003 (96). The percentage of female physicians obtaining a doctorate doubled during this period (1989: 9/64 (14); 2003: 28/96 (29)). Increasingly, physicians prepared their dissertation before or during their training as specialists or general practitioners (1989: 15/64 (23%); 2003: 51/96 (53%)). Ofthe clinical specialists who had received their doctorate, approximately half continued to work in an academic setting after obtaining their degree. This percentage remained approximately the same in all reference years (1989: 13/26 (50); 1994:19/35 (54); 1999: 21/45 (47); 2003: 21/40 (53)). CONCLUSION: Although the number of physicians performing scientific research as part of their doctoral degree project declined slightly in 2003 following an initial rise, our data indicate no cause for major concern. One reason may be increased interest in Clinical Research Fellow programmes. However, the future of medical research would look brighter if young physicians with doctorates had better career prospects within academic centres. To follow the academic careers of clinicians in The Netherlands, a national registry is needed to collect the type of data analysed in this study continually.

Different characteristics of ferrochelatase in cultured fibroblasts of erythropoietic protoporphyria patients and normal controls.

Ferrochelatase activity was measured in crude extracts of fibroblasts, obtained from erythropoietic protoporphyria patients and healthy controls. The enzyme activity in erythropoietic protoporphyria fibroblasts was about 50% lower, compared to the controls. The sulfhydryl-oxidising reagent diamide inhibited the normal enzyme by about 50%, whereas ferrochelatase from erythropoietic protoporphyria fibroblasts was completely insensitive to the reagent. Pb2+ inhibits ferrochelatase activity by reacting with essential sulfhydryl groups. Low concentrations of Pb2+ inhibited the normal enzyme by 56%, but the mutant enzyme by only 8%. The photodynamic activity of bound mesoporphyrin substrate caused a biphasic inactivation of the normal enzyme. During the first 5 min of illumination a fast decrease of enzyme activity occurred to about 60% of the initial value. Experimental evidence indicates that this first phase of inactivation is caused by photooxidation of sulfhydryl groups. During further illumination inactivation continued at a much slower rate. With ferrochelatase from erythropoietic protoporphyria fibroblasts only the second, slow phase of photodynamic inactivation was observed. These observations suggest a mutation of ferrochelatase in erythropoietic protoporphyria, affecting the reactivity of sulfhydryl groups, involved in the catalytic activity of the enzyme.

[Dutch medical specialists as authors of scientific publications in English on clinical drug research (1997/'03)]. / Nederlandse medisch specialisten als auteur van artikelen over klinisch geneesmiddelenonderzoek in engelstalige tijdschriften, 1997/'03.

OBJECTIVE: To determine the number and type of medical specialists in Dutch hospitals that were authors of scientific papers published in English in the field of clinical drug research in the period 1997/'03. DESIGN: Descriptive. METHOD: PubMed was searched for articles on clinical drug research published in February 1997-January 2003. (Co)authors were included if they were registered in the Geneeskundig Adresboek 2002-2003 (Medical Address Book 2002-2003) as a medical specialist working in a hospital. Hospitals were categorized as academic, non-academic teaching, general or non-affiliated. Journals were categorized by the type of published research: fundamental or biomedical, disease-specific, or specialty-specific. RESULTS: A total of 1776 articles in 426 journals were retrieved with at least 1 medical specialist listed as a (co)author. 1728 medical specialists were identified as authors, which represents 11% of the 16.065 registered medical specialists in The Netherlands. Most authors were involved in the nonsurgical specialties, primarily internist subspecialties, followed by paediatrics, cardiology, and neurology. The authors were employed in nearly all Dutch hospitals. The 1728 specialists had a total of 4952 authorships; 57% of the authors and 70% of the authorships came from academic hospitals. The average impact factor, the number of articles and the number ofauthorships were greatest in the disease-specific journal category. In the period 1997/'03 the number of authorships from non-academic teaching hospitals and general hospitals decreased, while the number of authorships from academic hospitals increased, particularly with regard to the number of co-authorships.

Synthesis of fusion proteins with multiple copies of an antigenic determinant of foot-and-mouth disease virus.

A series of four expression plasmids coding for fusion proteins containing foot-and-mouth disease virus (FMDV) sequences was constructed. The fusion proteins contain a large part of beta-galactosidase from Escherichia coli preceded (N-terminal) by 1, 2, 4 or 8 repeats of the antigenic determinant of FMDV consisting of amino acids 137-162 of the capsid polypeptide VP1. All four fusion proteins were efficiently produced in E. coli host bacteria. Immunization of rabbits resulted in FMDV-specific, neutralizing antibodies, the response being dependent on the number of repeats. With enzyme-linked immunosorbent-assay techniques it was shown that the FMDV antigenic determinants are exposed on the surface of the fusion proteins under non-denaturing conditions.

The effect of divalent and univalent binding on antibody titration curves in solid-phase ELISA.

This paper describes the influence of antigen coating concentration, epitope density per antigen molecule and anti-immunoglobulin reagents on antibody titration curves in solid-phase ELISA. Based on results obtained with fluorescein as the hapten and monoclonal anti-fluorescein antibody, which were confirmed in another antigen-antibody system, it is concluded that: (a) Antibody titration curves are independent of antigen-coating concentration in a limited range of concentrations only. (b) The complex between one antibody and two epitopes ('divalent binding') is more stable than the complex between one antibody and one epitope ('univalent binding). The ratio between divalent and univalent binding depends on the epitope density per antigen molecule and on the antigen-coating concentration. (c) The prozone phenomenon can be explained by an increased instability of plate bound antibodies due to a shift from divalent to univalent binding. (d) In solid-phase ELISA a correct evaluation of the antiserum specificity can be performed only if it is ascertained that all target antigens are coated under saturating conditions.

Development of a screening system for detection of somatic mutations. I. Enzyme immunoassay for detection of antibodies against specific hemoglobin determinants.

A solid-phase enzyme immunoassay for the detection of antibodies, specific for hemoglobin (Hb) is described. The application of glutaraldehyde resulted in a sensitive assay and allowed the use of urea, which is an important advantage if polypeptides not soluble in aqueous buffers are to be used. Mutation-carrying Hb chains can be purified, solubilized in urea and used in the immunoassay to monitor the purification and selection of antibodies specific for these variants. Specific antibodies are the main tools for the development of a hemoglobin-locus mutation system for detection of potentially mutagenic environmental agents. With erythrocytes as target cells, this system permits in vivo monitoring of subjects under exposure. Conventional antibody production, however, frequently turns out to be unsuccessful. The production of monoclonal antibodies has several advantages over conventional antibody production, but a sensitive antibody screening system is essential. Because of the sensitivity and the ease with which a large panel of antibody fractions against a vast panel of Hb antigens can be examined, the described immunoassay has potential value for the screening of hybridoma cultures.

Development of a screening system for detection of somatic mutations. II. The use of peptides and insoluble protein fragments in a non-competitive solid-phase enzyme immunoassay.

A system proposed for measurement of mutational risk consists in detection of hemoglobin mutations expressed in erythrocytes. For this detection the production of antibodies specific for Hb variants is essential. Recently we reported a sensitive solid-phase EIA for the production and selection of polyclonal and monoclonal antibodies specific for hemoglobin determinants. An important characteristic of this EIA was the coating of water-insoluble proteins to polystyrene microtiter plates. Here we report that with this system, insoluble protein fragments and small peptides may also be covalently coated to a polystyrene surface. Coating is independent of the length of the peptides. This allows direct, non-competitive titration of the antibody response to small peptides and avoids the drawbacks of competitive assay.

Use of bispecific hybrid antibodies for the development of a homogeneous enzyme immunoassay.

Hybrid bispecific monoclonal antibodies reacting with carcinoembryonal antigen (CEA) and with the E. coli enzyme beta-galactosidase (GZ) were produced by fusion of hybridomas or chemical linkage of half-antibodies. Since the original anti-GZ antibody used in these experiments was capable of protecting GZ from thermal denaturation, it was possible, by hybridizing it with two different non-competitive anti-CEA antibodies, to design a homogeneous enzyme immunoassay for quantitation of CEA. In fact, a mathematical analysis of the reaction indicates that, under appropriate concentrations of the reactants, circular complexes can be formed which contain the two hybrid antibodies, the GZ enzyme and the CEA antigen. The stability of these complexes can be expected to be substantially greater than that of the more labile CEA-free GZ-antibody complexes, prompting a significant increase in the amount of enzyme molecules which are bound to antibody and are consequently protected from thermal denaturation. These expectations were supported by experimental results: under appropriate conditions, heat-resistant enzyme activity was indeed proportional to concentration of CEA in the range up to 75 ng/ml. As predicted by theory, however, in the presence of excess CEA - in fact at CEA concentrations which are higher than those of possible clinical relevance - circular complexes tended to open up, leading to a marked prozone effect.

The flaccid lung syndrome and alpha 1-protease inhibitor deficiency.

We examined breathing mechanics and alpha 1PI deficiency in 1,850 unrelated male subjects with various lung complaints. The loss in lung elasticity appeared to be significantly more pronounced in ZZ individuals as compared to MM, MS and also MZ individuals. The MZ group did not differ significantly in this respect from MM individuals. This implies that the excess risk of developing a flaccid lung (C greater than 1 kPa-1) due to the partial alpha 1-antitrypsin deficiency is negligible. PI MZ and PI ZZ frequencies are significantly higher in the population with flaccid lung compared to control subjects. Furthermore, it was found that the increase in residual volume in smokers is independent of the PI type.

Clearance of alpha 1-antitrypsin isoelectric focusing patterns in blood samples treated with heparin.

Plasma samples, whose typing for alpha 1-AT is made difficult or impossible because of an excess of heparin used as anticoagulant, can be treated very effectively with protamine sulphate. The addition of this heparin antagonist results in complete clearance of the isoelectric focusing pattern.

Detection of alpha-1-antitrypsin deficiency variants by synthetic oligonucleotide hybridization.

Oligonucleotide probes, specific for the two most common deficiency variants, Z and S, of alpha-1-antitrypsin have been successfully applied for the diagnosis at the DNA-level. The possible presence of silent alleles necessitates a careful study of the parents both at the protein- and DNA-level in prenatal diagnostic cases.

[Research proposals submitted to the Dutch Investigative Medicine Fund; evaluation of the scientific quality by the Council for Scientific Research (NWO)]. / Aanvragen Ontwikkelingsgeneeskunde: de beoordeling van de wetenschappelijke kwaliteit door de Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO).

The Council for Medical and Health Research (MW-NWO) assessed the scientific quality of research proposals submitted to the Dutch Investigative Medicine Fund, and analysed if there had been changes over time in the proportion of proposals which the MW-NWO advised to reject, the role of reports of external reviewers and the most important methodological flaws. In the period 1995-1999 'reject' had been advised for an average of 50% of the proposals, with a tendency to a smaller proportion in recent years. In nearly half of the proposals the judgements of external reviewers were not in agreement with each other. There was only a weak correlation between the judgements of the reviewers and the final advice of NWO. Among the most important flaws mentioned in the NWO advice were: efficacy not proven (a prerequisite for the Fund), proposed study not needed to solve the policy problem and methodological flaws, e.g. design and power calculation not adequate, deficiencies of inclusion and exclusion criteria.

[Reporting of scientific misconduct in health care research]. / Melden van wetenschappelijk wangedrag in gezondheidsonderzoek.

The incidence of scientific dishonesty in the Netherlands is not known, yet experiences at both the NWO (the Netherlands Organization for Scientific Research) and Nederlands Tijdschrift voor Geneeskunde (Dutch Journal of Medicine) indicate that there must be several cases per year. For scientific fraud to be prevented students and researchers should receive thorough teaching, and in research laboratories an emphasis should be placed upon integrity. The Academic Medical Centre in Amsterdam has published a research protocol which is perfect for internal use. The Royal Netherlands Academy of Arts and Sciences publishes brochures on good research practice for researchers, teachers and students. The NWO and the Vereniging van Universiteiten (Dutch Association of Universities) have set up a committee for scientific integrity to function as a fallback mechanism and to assess the institutional procedures or to repeat the inquiries. As healthcare research institutions other than universities are involved since authorities are not always objective, an independent committee has been established to assess complaints about scientific dishonesty, the Scientific Integrity Health Research. Like the Committee on Publication Ethics it will publish its cases anonymously on an annual basis. Its judgments will be communicated to the people involved and the proper authorities.

[AGIKO (Clinical Research Fellow); a training model aimed at enhancement of clinical scientific research]. / 'Assistent-geneeskundige in opleiding tot klinisch onderzoeker' (AGIKO); opleidingsmodel ter versterking van klinisch-wetenschappelijk onderzoek door huisarts en specialist.

The enhancement of clinical scientific research in the Netherlands is being stimulated to a substantial extent by the introduction and stimulation of a training model aimed at the combined training of physicians to both a general practitioner or specialist and a clinical researcher, the AGIKO (Clinical Research Fellow). The model has been recognized by the Central College for Recognition and Registration of Medical Specialists. Extra stimulation by the section Medical Sciences of the Netherlands Organization for Scientific Research (MW-NWO) makes it possible to appoint AGIKOs on second or third flows of funds but also within the first flow of funds. During the last two years, 25 AGIKO applications from ten medical specialisms have been approved. The AGIKO model may help to meet (expected) needs for future clinical-medical research workers in specific research areas.

[A comparative study of the expenditures on health research in 7 western countries in 1997 places the Netherlands at the bottom of the list]. / Vergelijking van de uitgaven aan gezondheidsonderzoek in 7 westerse landen in 1997: Nederland op de laatste plaats.

OBJECTIVE: To compare the expenditures on health research in the Netherlands with those in other Western countries. DESIGN: Descriptive. METHOD: The expenditures on health research in 1997 were determined for the Netherlands, the United Kingdom, Germany, Norway, Denmark, Sweden and the USA and subsequently classified into: governmental funding for research in medical faculties or clusters; grants from MHRCs and other bodies; and private funding from industry and charities. The sources of information were the total research budgets 2002 of the Dutch Ministry of Education, Culture and Science, annual reports from charities, the Dutch Central Statistical Bureau and, for foreign countries, MHRCs or comparable institutions. RESULTS: In 1997, the Netherlands spent the equivalent of 855 million US dollars on health research (extremes of the investigated countries: 382 (Norway)-32,283 (USA)). This was less than in the other countries, whether calculated per capita, in US dollars (55 (Netherlands)-159 (Sweden)), as a promillage of the gross national product (2.27 (Netherlands)-5.84 (Sweden)), or as a percentage of the total expenditures for health care (2.62 (Netherlands)-7.54 (UK)). Especially the industrial expenditures on health research in the Netherlands were low, but the governmental expenditures were also lower than in the other countries.

[The SGO Health Research Promotion Program. XIV. Final evaluation]. / Het stimuleringsprogramma Gezondheidsonderzoek (SGO). XIV. Eindevaluatie.

In the Netherlands, the SGO Health Research Promotion Programme was carried out from 1986 until 1997. The aim of the programme was to strengthen patient-oriented clinical research in specific fields of medicine. Some of the programme sections certainly produced a number of good publications in established national and international journals, but the programme advisory committee's main objective was to bring about a cultural change in the field of health care investigation: awareness of the principle that scientific and notably patient-centred investigation has a place in its own right in research, education and care. This resulted in a large diversity of methods of stimulation ranging from stimulation of co-operation between researchers, training of physician researchers, support of methodology development, stimulation of education and postgraduate training, to establishment of actual institutes for clinical scientific research. Patient-oriented research is the necessary link within the continuum of health research, medical education and care. Changing social and demographic developments ask for continuous innovation of this type of research. Top-down steering, as practised by the SGO, can be necessary and effective to reach this innovation.