Corrigendum: Four new suomilides isolated from the cyanobacterium Nostoc sp. KVJ20 and proposal of their biosynthetic origin

[This corrects the article DOI: 10.3389/fmicb.2023.1130018.].

Four new suomilides isolated from the cyanobacterium Nostoc sp. KVJ20 and proposal of their biosynthetic origin

The suomilide and the banyasides are highly modified and functionalized non-ribosomal peptides produced by cyanobacteria of the order Nostocales. These compound classes share several substructures, including a complex azabicyclononane core, which was previously assumed to be derived from the amino acid tyrosine. In our study we were able to isolate and determine the structures of four suomilides, named suomilide B - E (1-4). The compounds differ from the previously isolated suomilide A by the functionalization of the glycosyl group. Compounds 1-4 were assayed for anti-proliferative, anti-biofilm and anti-bacterial activities, but no significant activity was detected. The sequenced genome of the producer organism Nostoc sp. KVJ20 enabled us to propose a biosynthetic gene cluster for suomilides. Our findings indicated that the azabicyclononane core of the suomilides is derived from prephenate and is most likely incorporated by a proline specific non-ribosomal peptide synthetase-unit.

Selective isolation of Arctic marine actinobacteria and a down-scaled fermentation and extraction strategy for identifying bioactive compounds

Actinobacteria are among the most prolific producers of bioactive secondary metabolites. In order to collect Arctic marine bacteria for the discovery of new bioactive metabolites, actinobacteria were selectively isolated during a research cruise in the Greenland Sea, Norwegian Sea and the Barents Sea. In the frame of the isolation campaign, it was investigated how different sample treatments, isolation media and sample-sources, such as animals and sediments, affected the yield of actinobacterial isolates to aid further isolation campaigns. Special attention was given to sediments, where we expected spores of spore forming bacteria to enrich. Beside actinobacteria a high share of bacilli was obtained which was not desired. An experimental protocol for down-scaled cultivation and extraction was tested and compared with an established low-throughput cultivation and extraction protocol. The heat-shock method proved suitable to enrich spore-, or endospore forming bacteria such as bacilli. Finally, a group bioactive compounds could be tentatively identified using UHPLC–MS/MS analysis of the active fractions.

Chlovalicin B, a Chlorinated Sesquiterpene Isolated from the Marine Mushroom Digitatispora marina

As part of our search for bioactive metabolites from understudied marine microorganisms, the new chlorinated metabolite chlovalicin B (1) was isolated from liquid cultures of the marine basidiomycete Digitatispora marina, which was collected and isolated from driftwood found at Vannøya, Norway. The structure of the novel compound was elucidated by spectroscopic methods including 1D and 2D NMR and analysis of HRMS data, revealing that 1 shares its molecular scaffold with a previously isolated compound, chlovalicin. This represents the first compound isolated from the Digitatispora genus, and the first reported fumagillin/ovalicin-like compound isolated from Basidiomycota. Compound 1 was evaluated for antibacterial activities against a panel of five bacteria, its ability to inhibit bacterial biofilm formation, for antifungal activity against Candida albicans, and for cytotoxic activities against malignant and non-malignant human cell lines. Compound 1 displayed weak cytotoxic activity against the human melanoma cell line A2058 (~50% survival at 50 µM). No activity was detected against biofilm formation or C. albicans at 50 µM, or against bacterial growth at 100 µM nor against the production of cytokines by the human acute monocytic leukemia cell line THP-1 at 50 µM.

Lulworthinone, a New Dimeric Naphthopyrone From a Marine Fungus in the Family Lulworthiaceae With Antibacterial Activity Against Clinical Methicillin-Resistant Staphylococcus aureus Isolates

The emergence of drug-resistant bacteria is increasing rapidly in all parts of the world, and the need for new antibiotics is urgent. In our continuous search for new antimicrobial molecules from under-investigated Arctic marine microorganisms, a marine fungus belonging to the family Lulworthiaceae (Lulworthiales, Sordariomycetes, and Ascomycota) was studied. The fungus was isolated from driftwood, cultivated in liquid medium, and studied for its potential for producing antibacterial compounds. Through bioactivity-guided isolation, a novel sulfated biarylic naphtho-α-pyrone dimer was isolated, and its structure was elucidated by spectroscopic methods, including 1D and 2D NMR and HRMS. The compound, named lulworthinone (1), showed antibacterial activity against reference strains of Staphylococcus aureus and Streptococcus agalactiae, as well as several clinical MRSA isolates with MICs in the 1.56-6.25 μg/ml range. The compound also had antiproliferative activity against human melanoma, hepatocellular carcinoma, and non-malignant lung fibroblast cell lines, with IC₅₀ values of 15.5, 27, and 32 μg/ml, respectively. Inhibition of bacterial biofilm formation was observed, but no eradication of established biofilm could be detected. No antifungal activity was observed against Candida albicans. During the isolation of 1, the compound was observed to convert into a structural isomer, 2, under acidic conditions. As 1 and 2 have high structural similarity, NMR data acquired for 2 were used to aid in the structure elucidation of 1. To the best of our knowledge, lulworthinone (1) represents the first new bioactive secondary metabolite isolated from the marine fungal order Lulworthiales.

Two Novel Lyso-Ornithine Lipids Isolated from an Arctic Marine Lacinutrix sp. Bacterium

The Lacinutrix genus was discovered in 2005 and includes 12 Gram-negative bacterial species. To the best of our knowledge, the secondary metabolite production potential of this genus has not been explored before, and examination of Lacinutrix species may reveal novel chemistry. As part of a screening project of Arctic marine bacteria, the Lacinutrix sp. strain M09B143 was cultivated, extracted, fractionated and tested for antibacterial and cytotoxic activities. One fraction had antibacterial activity and was subjected to mass spectrometry analysis, which revealed two compounds with elemental composition that did not match any known compounds in databases. This resulted in the identification and isolation of two novel isobranched lyso-ornithine lipids, whose structures were elucidated by mass spectrometry and NMR spectroscopy. Lyso-ornithine lipids consist of a 3-hydroxy fatty acid linked to the alpha amino group of an ornithine amino acid through an amide bond. The fatty acid chains were determined to be iso-C15:0 (1) and iso-C16:0 (2). Compound 1 was active against the Gram-positive S. agalactiae, while 2 showed cytotoxic activity against A2058 human melanoma cells.

Genomic characterization of three marine fungi, including Emericellopsis atlantica sp. nov. with signatures of a generalist lifestyle and marine biomass degradation

Marine fungi remain poorly covered in global genome sequencing campaigns; the 1000 fungal genomes (1KFG) project attempts to shed light on the diversity, ecology and potential industrial use of overlooked and poorly resolved fungal taxa. This study characterizes the genomes of three marine fungi: Emericellopsis sp. TS7, wood-associated Amylocarpus encephaloides and algae-associated Calycina marina. These species were genome sequenced to study their genomic features, biosynthetic potential and phylogenetic placement using multilocus data. Amylocarpus encephaloides and C. marina were placed in the Helotiaceae and Pezizellaceae (Helotiales), respectively, based on a 15-gene phylogenetic analysis. These two genomes had fewer biosynthetic gene clusters (BGCs) and carbohydrate active enzymes (CAZymes) than Emericellopsis sp. TS7 isolate. Emericellopsis sp. TS7 (Hypocreales, Ascomycota) was isolated from the sponge Stelletta normani. A six-gene phylogenetic analysis placed the isolate in the marine Emericellopsis clade and morphological examination confirmed that the isolate represents a new species, which is described here as E. atlantica. Analysis of its CAZyme repertoire and a culturing experiment on three marine and one terrestrial substrates indicated that E. atlantica is a psychrotrophic generalist fungus that is able to degrade several types of marine biomass. FungiSMASH analysis revealed the presence of 35 BGCs including, eight non-ribosomal peptide synthases (NRPSs), six NRPS-like, six polyketide synthases, nine terpenes and six hybrid, mixed or other clusters. Of these BGCs, only five were homologous with characterized BGCs. The presence of unknown BGCs sets and large CAZyme repertoire set stage for further investigations of E. atlantica. The Pezizellaceae genome and the genome of the monotypic Amylocarpus genus represent the first published genomes of filamentous fungi that are restricted in their occurrence to the marine habitat and form thus a valuable resource for the community that can be used in studying ecological adaptions of fungi using comparative genomics.

Antimicrobial Activity of Securamines From the Bryozoan Securiflustra securifrons

Natural products and their derivatives have served as powerful therapeutics against pathogenic microorganisms and are the mainstay of our currently available treatment options to combat infections. As part of our ongoing search for antimicrobial natural products from marine organisms, one fraction prepared from the Arctic marine bryozoan Securiflustra securifrons was found to be active against the human pathogenic bacterium Streptococcus agalactiae (gr. B). Chemical investigation of the fraction revealed that it contained several variants of the highly modified secondary metabolites known as securamines. The securamines are alkaloids sharing a common isoprene-histamine-tryptamine backbone. In this study, we describe the antimicrobial activities of securamine C, E, and H – J (4, 5, and 1-3) and the attempt to deconvolute the mode of action of 1.

Bioactivity of Serratiochelin A, a Siderophore Isolated from a Co-Culture of Serratia sp. and Shewanella sp

Siderophores are compounds with high affinity for ferric iron. Bacteria produce these compounds to acquire iron in iron-limiting conditions. Iron is one of the most abundant metals on earth, and its presence is necessary for many vital life processes. Bacteria from the genus Serratia contribute to the iron respiration in their environments, and previously several siderophores have been isolated from this genus. As part of our ongoing search for medicinally relevant compounds produced by marine microbes, a co-culture of a Shewanella sp. isolate and a Serratia sp. isolate, grown in iron-limited conditions, was investigated, and the rare siderophore serratiochelin A (1) was isolated with high yields. Compound 1 has previously been isolated exclusively from Serratia sp., and to our knowledge, there is no bioactivity data available for this siderophore to date. During the isolation process, we observed the degradation product serratiochelin C (2) after exposure to formic acid. Both 1 and 2 were verified by 1-D and 2-D NMR and high-resolution MS/MS. Here, we present the isolation of 1 from an iron-depleted co-culture of Shewanella sp. and Serratia sp., its proposed mechanism of degradation into 2, and the chemical and biological characterization of both compounds. The effects of 1 and 2 on eukaryotic and prokaryotic cells were evaluated, as well as their effect on biofilm formation by Staphylococcus epidermidis. While 2 did not show bioactivity in the given assays, 1 inhibited the growth of the eukaryotic cells and Staphylococcus aureus.

Lysophosphatidylcholines and Chlorophyll-Derived Molecules from the Diatom Cylindrotheca closterium with Anti-Inflammatory Activity

Microalgae have been shown to be excellent producers of lipids, pigments, carbohydrates, and a plethora of secondary metabolites with possible applications in the pharmacological, nutraceutical, and cosmeceutical sectors. Recently, various microalgal raw extracts have been found to have anti-inflammatory properties. In this study, we performed the fractionation of raw extracts of the diatom Cylindrotheca closterium, previously shown to have anti-inflammatory properties, obtaining five fractions. Fractions C and D were found to significantly inhibit tumor necrosis factor alpha (TNF-⍺) release in LPS-stimulated human monocyte THP-1 cells. A dereplication analysis of these two fractions allowed the identification of their main components. Our data suggest that lysophosphatidylcholines and a breakdown product of chlorophyll, pheophorbide a, were probably responsible for the observed anti-inflammatory activity. Pheophorbide a is known to have anti-inflammatory properties. We tested and confirmed the anti-inflammatory activity of 1-palmitoyl-sn-glycero-3-phosphocholine, the most abundant lysophosphatidylcholine found in fraction C. This study demonstrated the importance of proper dereplication of bioactive extracts and fractions before isolation of compounds is commenced.

Kinase Chemodiversity from the Arctic: The Breitfussins

In this work, we demonstrate that the indole-oxazole-pyrrole framework of the breitfussin family of natural products is a promising scaffold for kinase inhibition. Six new halogenated natural products, breitfussin C-H (3 - 8) were isolated and characterized from the Arctic, marine hydrozoan Thuiaria breitfussi. The structures of two of the new natural products were also confirmed by total synthesis. Two of the breitfussins (3 and 4) were found to selectively inhibit the survival of several cancer cell lines, with the lowest IC₅₀ value of 340 nM measured against the drug-resistant triple negative breast cancer cell line MDA-MB-468, while leaving the majority of the tested cell lines not or significantly less affected. When tested against panels of protein kinases, 3 gave IC₅₀ and K_d values as low as 200 and 390 nM against the PIM1 and DRAK1 kinases, respectively. The activity was confirmed to be mediated through ATP competitive binding in the ATP binding pocket of the kinases. Furthermore, evaluation of potential off-target and toxicological effects, as well as relevant in vitro ADME parameters for 3 revealed that the breitfussin scaffold holds promise for the development of selective kinase inhibitors.

Anti-Bacterial Effect and Cytotoxicity Assessment of Lipid 430 Isolated from Algibacter sp

Two bacterial isolates from the Barents Sea, both belonging to the genus Algibacter, were found to yield extracts with anti-bacterial bioactivity. Mass spectrometry guided dereplication and purification of the active extracts lead to the isolation of the same active principle in both extracts. The structure of the bioactive compound was identified via mass spectrometry and nuclear resonance spectroscopy and it turned out to be the known lipopeptide Lipid 430. We discovered and determined its previously unknown anti-bacterial activity against Streptococcus agalactiae and revealed a cytotoxic effect against the A2058 human melanoma cell line at significantly lower concentrations compared to its anti-bacterial concentration. Flow cytometry and microscopy investigations of the cytotoxicity against the melanoma cell line indicated that Lipid 430 did not cause immediate cell lysis. The experiments with melanoma cells suggest that the compound functions trough more complex pathways than acting as a simple detergent.

Serious adverse events reported for antiobesity medicines: postmarketing experiences from the EU adverse event reporting system EudraVigilance

BACKGROUND

Use of antiobesity medicines has been linked with serious cardiac and psychiatric adverse events (AEs). Spontaneous reports can provide information about serious, rare and unknown AEs occurring after the time of marketing. In Europe, information about AEs reported for antiobesity medicines can be accessed in the EudraVigilance (EV) database. Therefore, we aimed to identify and characterise AEs associated with the use of antiobesity medicines in Europe.

METHODS

AE reports submitted for antiobesity medicines (Anatomical Therapeutic Chemical (ATC) group A08A) from 2007 to 2014 and located in the EV database were analysed. AE data were categorised with respect to time, age and sex of patient/consumer, type of reporter, category and seriousness of reported AEs and medicines. Consumer AE reports were compared with reports from other types of reporters with respect to age and sex of consumer, seriousness, system organ class and medicine. The unit of analysis was one AE and one AE report, respectively.

RESULTS

We located 4941 AE reports corresponding to 13 957 AEs for antiobesity medicines in the EV database. More than 90% of all AE cases were serious, including 159 deaths. The majority of AE cases were reported for female adults. The majority of serious AEs was reported for orlistat (37%) and rimonabant (22%). The largest share of serious AEs was of the type 'cardiac disorders' (19%) and 'psychiatric disorders' (18%). Consumer AEs reporting differed from other sources with respect to share and seriousness of AEs, type of AEs (system organ class) and medicines (ATC level 5).

CONCLUSIONS

Many serious AEs were found for antiobesity medicines in EV, and consumers contributed with a relatively high share of reports. Although several products have been withdrawn from the market and new medicines are being marketed, the utilisation of antiobesity medicines is widespread, and therefore systematic monitoring of the safety of these medicines is necessary.

Socio-economic status and adherence to tuberculosis treatment: a case-control study in a district of Nepal

SETTING

A western hill district in Nepal, where tuberculosis (TB) treatment under DOTS was offered by the regional tuberculosis centre, two primary health centres, eight health posts, three sub-health posts and one ward of sub-metropolitan Pokhara.

OBJECTIVE

To analyse the contribution of socioeconomic status to non-adherence to DOTS.

DESIGN

Case-control study. Data were collected by questionnaire-based face-to-face interviews. The study sample consisted of 50 cases and 100 controls. The participation rate was 80% for cases (non-adherents) and 95% for controls.

RESULTS

Logistic regression analysis showed that the risk of non-adherence to TB treatment was significantly associated with unemployment (odds ratio [OR] 9.2), low status occupation (OR 4.4), low annual income (OR 5.4), and cost of travel to the TB treatment facility (OR 3.0). Factors significant in the bivariate analyses--living conditions, literacy and difficulty in financing treatment--were not found to be significantly associated with non-adherence when adjusted for other risk factors in the multivariate regression model.

CONCLUSION

Low socio-economic status and particularly lack of money are important risk factors for non-adherence to TB treatment in a poor country such as Nepal.

Use of six main drug therapeutic groups across educational groups: self-reported survey and prescription records

OBJECTIVES

To assess whether the use of six main therapeutic groups was congruent with the occurrence of related diseases across educational groups.

METHODS

Two data sources were analysed: (i) Interview data from The Danish Health and Morbidity Survey 2000 on a representative sample of the Danish population ages 16 years and above (n = 16,690); (ii) Prescription records linked to a health survey on a representative sample of the population of Funen County 2000-2001 (n = 3,422). The use of six therapeutic main groups (ATC groups A, B, C, M, N and R) and related diseases in educational groups was analysed by indirect standardization. Age and gender standardized prevalence ratios (SPRs) and 95% confidence intervals were calculated on the basis of the total study population.

RESULTS

In general, respondents in the two least educated groups used medicines more frequently and a higher proportion of them reported the related disease than could be expected from indirect standardization. The opposite picture appeared for respondents in the two highest educational groups (SPR < 100). The overall patterns were similar for the six medicine groups, although some of the SPRs were not significant.

CONCLUSION

The results show the uneven distribution of disease in the general population. The distribution of medicine use generally followed this pattern, which means that those in the greatest medical need used the most medicine. Hence, individual co-payment for medicine did not seem to be a barrier to access to medicine in any of the educational groups.

Effect of environmental and physiological factors on the antibacterial activity of Curvularia haloperoxidase system against Escherichia coli

AIMS

The aim of this study was to investigate the influence of environmental and physiological factors on the susceptibility of Escherichia coli to the Curvularia haloperoxidase system.

METHODS AND RESULTS

The Curvularia haloperoxidase system is a novel enzyme system that produces reactive oxygen species which have an antimicrobial effect. Escherichia coli MG1655 was exposed to the Curvularia haloperoxidase system under different temperatures and NaCl concentrations and after exposure to different stress factors. Temperature clearly affected enzymatic activity with increasing antibacterial effect at increasing temperature. The presence of NaCl interfered with the enzyme system and in the presence of 1% NaCl, no antibacterial effect could be observed at pH 7. Cells grown at pH 8.0 were in one experiment more resistant than cells grown at pH 6.5, whereas cells grown in the presence of 2% NaCl were more susceptible to the Curvularia haloperoxidase system.

CONCLUSIONS

Environmental and physiological factors can affect the antibacterial activity of the Curvularia haloperoxidase system.

SIGNIFICANCE AND IMPACT OF THE STUDY

The study demonstrates a systematic approach in assessing the effect of environmental and physiological factors on microbial susceptibility to biocides. Such information is crucial for prediction of application as well as potential side-effects.

The provision of pharmaceutical care in Denmark: a cross-sectional survey

BACKGROUND

Pharmaceutical care was a concept initially defined in the early 1990s. It had its roots within clinical pharmacy, in the USA. In Denmark, pharmaceutical care has been part of the professional standards of practice for community pharmacy since 1995.

OBJECTIVE

The objective of the present study was to investigate the provision of pharmaceutical care in community practice in Denmark. A focus of the study was the estimation of the frequency of medicine-related problem identification and the process of problem management in the Danish pharmacies.

METHODS

A cross-sectional questionnaire-based survey of all Danish community pharmacies was conducted (n = 288). The variables included: detection and identification of medicine-related problems, goal-setting for solving medicine-related problems, and documentation of efforts to solve these. The response rate was 75.7%. A non-respondent analysis was performed.

RESULTS

On average three medicine-related problems per pharmacy were found within the working week prior to the survey. For two-thirds of those cases the type of problem involved was identified. For the other third, goals had been set to resolve the problem. Minimal documentation of these activities was reported. The primary collaborators in problem management were general practitioners and patients.

CONCLUSION

Pharmaceutical care, in its fullest sense, as defined in policy documents in Denmark, was not evident in practice. While some aspects of pharmaceutical care were being performed, almost no documentation of efforts was taking place in community pharmacy.

Ethical dilemmas in antibiotic prescribing: analysis of everyday practice

OBJECTIVE

To explore general practitioners' (GP's) views on their obligations with respect to diagnosing infections and prescribing antibiotics.

METHODS

The GP's reflections and prioritization were studied by means of interviews and observations. We analysed how their prioritization complied with an ethical guidance that ranked patient autonomy and welfare highest, then competence obligations and obligations to society, followed by fraternal obligations.

RESULTS

Balancing of pros and cons was prominent in our informants' decision making but often resulted in decisions that deviated from the ethical guidance. The ranking varied much between the GPs. The highest priorities in the GPs' practice were related to the patient's everyday life (sometimes autonomy, sometimes beneficence in a broad sense), doctor-patient relationship (communication competence), the patient's perceived importance on the job market (society) and relationship with colleagues (fraternal). Perceived lack of resources and uncertainty with respect to both diagnostic and treatment decisions frequently influenced decision making.

Treatment of upper respiratory tract infections--a comparative study of dispensing and non-dispensing doctors

BACKGROUND

The reported results are part of an overall evaluation of drug management by dispensing (DDs) and non-dispensing doctors (NDDs). This study focuses on appropriate prescription. Other studies assess good pharmacy practice. Whereas rationality of prescription has been studied based on simple indicators, appropriate prescription in relation to diagnoses and symptoms has not been assessed.

OBJECTIVE

To analyse prescriptions by DDs and NDDs for patients diagnosed with upper respiratory tract infection.

METHODS

Cohort study of 28 private sector DDs and 28 NDDs, using retrospective registry data from a mean of 14.5 and 16.0 patient records per practice, respectively.

OUTCOME MEASURES

Drug choice, frequency of the drugs being used, use of antibiotics and dosages for respiratory infections where antibiotics are/are not justified.

RESULTS

DDs were associated with a greater number of drugs per encounter (P < = 0.001), a greater number of injections (P = < 0.002), more use of analgesic drugs (P = < 0.001), cough and cold preparations (P < 0.001) and psycholeptics (P = < 0.03). The choice of antibiotics for upper respiratory tract infection (URTI) was assessed as rational, although different for the two practices, but both practices over-prescribe antibiotics frequently. Dispensing doctors frequently prescribe sub-curative dosages and fewer curative dosages (P = < 0.001), compared with NDDs.

CONCLUSION

Irrational prescription for URTI is widespread by both dispensing doctors and to a lesser extent, by NDDs. Symptomatic treatments with 'a drug for each symptom' was common, particularly by the DDs. There was also over-prescription of antibiotics and use of sub-therapetitic dosages. This poly-pharmacy, poses a safety risk, a risk of development of resistance and, unnecessarily costly treatment.

Telephone prescribing of antibiotics. General practitioners' views and reflections

BACKGROUND

In this era of increasing problems with resistance, rational prescribing of antibiotics is extremely important. Therefore, rationales for prescribing require analyses. The objective of this study was to explore general practitioners' (GPs') reasons for prescribing antibiotics by telephone.

METHODS

Qualitative analysis of semistructured interviews with and observations of GPs in Iceland enquiring about the rationale for prescribing antibiotics was used. Ten GPs were interviewed for 45 min to 2 h each including three who were observed between 3 and 10 h.

RESULTS

The GPs generally indicated a restrictive attitude to telephone prescribing, although they all gave examples of their prescribing by telephone. The prescribing was mostly but not always based on some kind of diagnosis. The factors influencing diagnosis and prescribing were largely non-clinical: knowledge of the patients as persons, including their complaint threshold, confidence in their descriptions, the GPs' communication strategies and the travelling distance between patients and GPs. The clinical factors were the patients' description of signs and symptoms and knowledge of their history. Prescriptions not based on diagnosis were 'therapeutic trial' or GP-approved self-medication. Sometimes, the GPs requested to see a patient even though the diagnosis was based on history, signs and symptoms.

CONCLUSIONS

Multiple factors affected the decision-making process when antibiotics were prescribed by telephone, most of which were non-clinical. The diagnosis, if there was one, was generally presumptive. GPs' general attitudes correlated well with current knowledge but were contrasted by the reality of their daily work conditions.

Experiences of long-term tranquillizer use: a psychodynamic perspective

The aim of the article is to analyse narrative descriptions and experiences of long-term tranquillizer use. The analysis is based on a Danish in-depth study of 50 informants with a self-diagnosed dependency on tranquillizers. The theoretical analysis is dependent on psychodynamic reasoning. Further, the psychodynamic perspective is integrated within a multi-dimensional model that considers biological, cognitive, identity, gender and social learning factors. The analysis reveals the possibility of achieving a detailed understanding of the dynamic processes involved in the development of long-term tranquillizer use. Important themes frequently mentioned in the clients' descriptions are traumatic childhood experiences, identity problems, life crises in adulthood and difficulties in stopping taking psychotropic drugs.

Quality assessment of drug sales data: the case of antibacterials in Iceland

BACKGROUND

Two sets of drug sales data, published by the Icelandic Ministry of Health, did not match for antibacterials in 1989. The search for causes turned out to be a project in itself.

OBJECTIVE

To analyze quality problems in the sales data on antibacterials and describe a method for systematic quality assessment of drug sales data.

METHODS

Documentary analysis based on the following sources: 1) Nordic Statistics on Medicines, 1975-95; 2) Drug Use (Notkun Iyfja), 1975-93; 3) Icelandic Drug Market, 1975-94; 4) Unpublished data from the Icelandic Ministry of Health. The following framework was developed to evaluate the quality of drug sales data: 1. Completeness of registration; 2. Accuracy and degree of completeness of data; 3. Size and coverage of the data source; 4. Data format; 5. Data accessibility, availability and cost.

RESULTS

Four discrepancies were found, two due to changes in DDD, and two larger ones stemming from errors in calculating DDD, resulting in an overestimation of the contribution of the respective products to the total DDD/1000 inhabitants/day. Errors were detected in available sales data at least back to 1980, resulting in sales being overestimated by up to 13%. The reasons for the discrepancies were found mostly under point 2 in the framework.

CONCLUSION

The errors uncovered by this study indicate a possible low quality of drug statistics which might lead to wrong conclusions about the level and development of sales of drugs. As a tool, the framework might be used for quality assessment of drug sales data.

The quality of immunization data from routine primary health care reports: a case from Nepal

Reported high immunization coverage achieved in Nepal over the last ten years is expected to reduce child mortality in the country. The present study, carried out in hill district in mid-west Nepal, aimed to assess the quality of immunization data in Nepal. The number of children who received different vaccines during one year was obtained from three sources: 1) the Immunization REgister of three Primary Health Care Service Outlets (PHCSOs) where each immunized child is recorded; 2) monthly PHC Reports, which are based on the Immunization Register; 3) monthly DHO Reports, which are based on the above PHC Reports (the DHO reports are the source of official statistics). The number of children in the PHC Reports was higher than the number in the Immunization REgisters for all vaccines. The number of immunizations in the DHO Reports was higher than the number in the PHC Reports for BCG, DPT, and measles; the number was lower for poliomyelitis. The overall number of immunizations was higher in the DHO Reports than in the Immunization Registers, by 31% for BCG, 44% for DPT, 155% for polio, and 71% for measles. We conclude that the official report overestimates the immunization coverage in the district. The immunization programme, therefore, might not result in the expected reduction of morbidity and mortality despite the investment in the programme and reported high coverage.

The effect of hyperbaric oxygen on irradiated oral tissues: transmucosal oxygen tension measurements

PURPOSE

This study measured the effect of hyperbaric oxygen (HBO) treatment on transmucosal oxygen tension in irradiated human oral mucosa.

PATIENTS AND METHODS

Ten patients received 30 dives of HBO as part of their treatment for mandibular osteoradionecrosis. A noninvasive, nonheated oxygen electrode was used to measure the tissue surface transmucosal oxygen tension directly on the attached gingiva. Measurements were done before, during, and after HBO treatment. The normal level of gingival surface transmucosal oxygen tension was measured in five healthy volunteers.

RESULTS

During HBO treatment, the transmucosal oxygen tension increased significantly after five dives of HBO (P < .05). After 30 dives, the increases were from a mean of 50% to a mean of 86% of the transmucosal oxygen tension of normal healthy gingiva.

CONCLUSION

An increase in the transmucosal oxygen tension is based on neo-angiogenesis. Patients with subischemic tissues, such as the study population with postirradiation mucosal and osseous necrosis, therefore may benefit from treatment with HBO.

Principles and applications of flow injection analysis in biosensors

In practical applications biosensors are often forced to operate under less than optimal conditions. Because of their construction, and the physical processes and chemical reactions involved in their operation, compromise conditions are frequently required to synchronize all events taking place. Therefore, and in order to implement functions such as periodic calibration, conditioning and possible regeneration of the biosensor, and, very importantly, to yield the freedom to select the optimum detection means, it is advantageous to use these devices in a flow-through mode, particularly by employing the flow injection (FI) approach. The capacity of FI, as offering itself as a complementary facility to augment the performance of biosensors, and in many cases as an attractive alternative, is demonstrated by reference to selected examples, comprising assays based on enzymatic procedures with optical and thermal detection procedures, and via description of a recently introduced technique for immunoassays, termed flow injection renewable surface immunoassays, which promises to entail powerful potentials and to yield compatible or better economy of operation than existing approaches.

Determination of minute amounts of ATP by flow injection analysis using enzyme amplification reactions and fluorescence detection

A flow-injection system for assay of trace levels of ATP is described that incorporates a small column reactor containing co-immobilized hexokinase, pyruvate kinase and glucose-6-phosphate dehydrogenase. In the presence of appropriate cofactors, ATP is by the synergistic operation of the enzymes repeatedly recycled, resulting in substrate amplification. The ultimately generated NADH is measured fluorometrically. By this approach, where the enzymatic degradation step and the detection step are completely separated, it is possible to operate them individually under optimal conditions. The amplification factor is directly proportional to the residence time of the sample zone within the enzyme reactor, which time might be manipulated by altering the flow-rate and in the extreme by performing stopped-flow experiments. Amplification factors between 15 and 1000 were obtained, but it was found that increased amplifications did not lead to significantly lower detection limits; thus, it appears that a practical lower limit of detection is of the order of 1-5 nM. An investigation of this paradoxical feature, and a possible explanation for it, is given.

Technology assessment in a user perspective--experiences with drug technology

Drugs have a central place among medical technologies, and medical technology assessment can learn from the established regulation of drug technology. This article outlines how users' experiences are not part of the basis on which decisions are made today, although this knowledge is imperative for identifying the problems that are not uncovered or foreseen by today's drug assessments. Further, users' interests might not be part of assessments that are based on the controlled clinical trial. A framework for drug technology assessments based on a user perspective is suggested.

Spectrophotometric flow injection determination of trace amounts of thiocyanate based on its reaction with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol and dichromate: assay of the thiocyanate level in saliva from smokers and non-smokers

A simple and very sensitive spectrophotometric flow injection (FI) procedure for the determination of trace amounts of thiocyanate is described. The proposed method is based on the reaction between thiocyanate and 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol, which, in 2 mol dm-3 acidic media in the presence of a strong oxidizing agent, produces an intensely coloured product. Several oxidants are potentially applicable, but it is shown that dichromate is preferable. As the reaction product formed is unstable and the signal inherently is recorded on a high background level, it is demonstrated that FI constitutes an ideal method in order to monitor reproducibly and repeatedly the kinetically transient signal that is obtained. Based on optimization by a factorial experimental design, the detection limit of the procedure was found to be 3.5 mumol dm-3, and the standard deviation between samples was 0.16 mumol dm-3. No significant interferences were observed; a 1000-fold excess of cyanide could readily be tolerated within the experimental error. With a sample volume of 50 microliters being injected, the sampling frequency was 60 samples h-1. The system was tested with saliva samples from non-smokers and smokers, and the results show that it is possible to distinguish between these two categories of individuals. As an added benefit, the detection limit of the analytical procedure allows the samples to be diluted 100-fold, so that centrifugation for 5 min is the only preliminary sample preparation that is necessary.

Development, use and evaluation of drugs: the dominating technology in the health care system

The article presents various perspectives of drug technology and health care policy in Denmark. Drugs dominate as the most widely used treatment technology in the health care system and the use of drugs is steadily increasing. The pharmaceutical industry's development of drugs is based on an economic estimate of developments, expenditures, marketing costs and the anticipated share of the market. Controlled clinical trials have become the main form of documentation required by the health authorities. This method is insufficient to evaluate the (side) effects of the drugs when in actual use. Drugs fit perfectly the technical perception of disease, a perception which prevails in the pharmaceutical industry, medical science and in the treatment of disease. This perception believes that a disease is due to an attack or dysfunction in the biological-mechanical conditions of the individual. Drugs offer a standard solution to health problems independent of the individuals' social life. Thus drugs become a tool which function in agreement with the disintegrated and achievement-orientated approach to disease as it is organized today. In general the statements in this article are not limited to special Danish circumstances but are valid for other countries as well [1, 2]. (Norris R. Pills, Pesticides & Profits. North River Press, 1982; Braithwaite J. Corporate Crime in the Pharmaceutical Industry. Routledge & Kegan Paul, London, 1984) The empirical data in this article derive from Denmark, however.

The active medicine user

The purpose of the study is to analyse medicine behaviour seen from the user's point of view. The study intends to generate ideas to specify topics of problems and to try out a combination of qualitative research methods. The practitioners and four asthmatic patients attached to a health centre in Billund, Denmark, were interviewed. The patients kept a diary based on topics, the notes of which were elaborated by weekly telephone interviews. In a final interview all participants evaluated the course of the study. The combination of qualitative methods has been very suitable to provide the perspective of the user. The results of the study question the ideal picture of the patient as a passive user of medicine. The main trends show that: the users develop different strategies to evaluate medication therapy; it has negative consequences to the patient when medication is changed regardless of patient experience; the therapy improves when the doctor draws on the experience of the patient. The study contributes to the present, sparse knowledge about the consciously acting user of medicine and indicates the importance of incorporating the user's experience and life situation in the health care system's handling of health problems.

Number and type of psychotropic drugs on the Scandinavian market in 1950-1977

This article describes the number and types of psychotropic drugs on the market in Denmark, Finland, Norway, and Sweden from 1950-1977. The total number of drugs on the market in each country depended greatly on how psychotropic drugs were defined, but trends with time and differences between the countries were less affected by this definition. The number of drugs was highest in Finland and lowest in Norway. In all countries, the number of drugs increased from 1950 to the mid-1960s, most abruptly in Finland. They then quickly decreased in Finland and Sweden, but remained fairly constant in Denmark and Norway. The number of different active substances was much smaller than the number of drugs, and the differences between the countries were also smaller. The proportions of combination and hidden psychotropic drugs in relation to all psychotropics were considerable in Finland and Sweden, and the varying numbers of combination drugs contributed greatly to the wide differences in the number of drugs. From the medical point of view, far too many drugs were on the market in that period.

Hydroxychloroquine sulphate in prevention of deep venous thrombosis following fracture of the hip, pelvis, or thoracolumbar spine

One hundred and fifty-three patients, forty-eight to ninety-seven years old, were included in a double-blind placebo-controlled investigation of the usefulness of hydroxychloroquine sulphate for the prevention of deep venous thrombosis in patients with fractures of the hip, pelvis, or thoracolumbar spine. The results indicated that this drug can reduce the number of thrombeombolic complications significantly (p less than 0.005), a finding that corresponds to the results obtained with other drugs such as coumarin derivatives or dextran 70.

Intra-arterial infusion of prostaglandin E1 in normal subjects and patients with peripheral arterial disease

Acute vasodilatation was produced by infusion of prostaglandin E1 (PGE1) in the femoral artery in 6 patients with occlusive arterial disease of the legs and in 3 normal subjects. The effect on blood flow and on blood pressure was measured at different segments of the leg with the strain gauge technique, isotope clearance technique, and photoelectric technique. Skin temperature was measured at different levels by using thermocouples. The blood pressure on the legs decreased at all segments during vasodilatation as well in patients as in controls. The blood flow increased in all segments in normal controls. In patients the blood flow increased proximally in the legs. Distally, however, no increase could be demonstrated. As a good effect of PGE1, on ischaemic rest pains has been reported, mechanisms other than vasodilatation should probably be considered.