Heroin impurity profiling. A harmonization study for retrospective comparisons

Three laboratories present a harmonised system for the retrospective comparison of south west Asian heroin. It consists of an improved gas chromatographic (GC) profiling method and a computerised data retrieval. The investigations of the GC were necessary with a view to improve the reproducibility of the system. The necessity of a strict quality control is emphasized. The peaks of the GC profile were investigated for abundance, intensity, GC behaviour (reproducibility) and correlations; 16 of them were selected for describing the heroin profile in the database. The results from intra-lab profile comparisons are reported. The reproducibility of the analysis was good and the variation between the samples was large, thus, allowing conclusions with a high degree of certainty. The criteria of similarity were defined. The system is successfully running in all three labs. In connection with inter-laboratory comparison, the aspects of method harmonisation and standardisation are discussed. It appeared that the GC method is a very subtile one, urging for a strict standardisation between the three labs. Despite a long cooperation between three well-equipped and experienced labs, a more or less serious loss of reproducibility was noticed in the inter-lab results in comparison with the intra-lab results. The loss could for the greater part be attributed to the (limits of the) GC technique; a number of compounds, necessary for making the discrimination between samples, showed difficult chromatographic behaviour, leading to insufficient inter-lab reproducibility. Using the actual variables, improvements in performance can hardly be expected in the near future. The loss of reproducibilty implies that the number of false positive matches in a database search increases. This may strongly reduce the value of a relatively large, international database. The study shows that so far, the best option for international comparison is the analysis in a central laboratory. The idea of local determination at a large number of national labs and the use of a common database is not a realistic aim for this type of analysis.

Health-related quality of life in patients with psoriasis and atopic dermatitis measured with SF-36, DLQI and a subjective measure of disease activity

The impact of skin diseases on health-related quality of life is considerable. It is important to quantify the patient's perspective of the severity of their disease. Health-related quality of life was measured in 366 patients with skin diseases attending the dermatology outpatient clinic in Uppsala, Sweden, from November 1996 to December 1997, with 1 generic (SF-36) and 1 disease-specific (DLQI) health-related quality of life instrument, and a subjective measure of disease activity. The SF-36 mean scores were below those of the age- and gender-matched general population in Sweden. No difference in health-related quality of life was found between men and women or between patients with atopic dermatitis and psoriatic patients. However, patients with psoriatic arthritis had significantly poorer health-related quality of life than both patients with atopic dermatitis and psoriatic patients. The estimated correlations between the instruments were in the expected direction and mostly significant. The results confirm that skin diseases have an adverse impact on patients' health-related quality of life.

Quality of life, health-state utilities and willingness to pay in patients with psoriasis and atopic eczema

Skin diseases have been shown to have a significant adverse impact on the health-related quality of life of patients that may be underestimated by objective assessments of clinical severity. The main aim of this study was to measure the health-state utilities on a scale between 0 (dead) and 1 (full health) of patients with psoriasis and atopic eczema, and to measure the willingness to pay for a cure for psoriasis and atopic eczema. A second aim was to analyse how these measures are related to different dimensions of health-related quality of life, as measured by general and disease-specific quality of life instruments and a subjective measure of disability activity. This study was based on data from a questionnaire administered to, and interviews conducted with, 366 patients with psoriasis and atopic eczema aged 17-73 years, attending the dermatology outpatient clinic in Uppsala, Sweden from November 1996 to December 1997. The survey included: a rating scale question, a time trade-off question, a standard gamble question, a dichotomous choice willingness to pay question, a bidding-game willingness to pay question, a generic quality of life instrument (SF-36), a disease-specific quality of life instrument (the Dermatology Life Quality Index) and a subjective measure of disease activity (on a visual analogue scale). The mean health-state utility was 0.69 (rating scale), 0.88 (time trade-off) and 0.97 (standard gamble) for patients with psoriasis. The corresponding health-state utilities for patients with atopic eczema were 0.73, 0.93 and 0.98. On average, patients were willing to pay between 1253 and 1956 Swedish crowns (SEK) per month for a psoriasis cure and between SEK 960 and 1083 per month for an atopic eczema cure ($1 = SEK 8.25 and pound1 = SEK 13.23). The health-state utilities were related to SF-36, the Dermatology Life Quality Index and disease activity in the expected direction and the correlations were strongest for rating scale and weakest for standard gamble. The willingness to pay was correlated with the Dermatology Life Quality Index and disease activity, but not with SF-36. The study indicates that it is feasible to measure health-state utilities and willingness to pay in this patient population, and the sizeable willingness to pay suggests that skin diseases are associated with substantial reductions in quality of life.

Maternal distress and congenital malformations: do mothers of malformed fetuses have more problems?

As compared with 580 randomly chosen pregnant women without malformed offspring. 161 women with malformed offspring at the index pregnancy had a more frequent history of previous multiple offspring deaths and somewhat increased maternal age but were not different on social class, marital or cohabitation status or parity. As compared with demographically similar reproducing women (n = 54) interviewed, malformation cases (n = 98) reported having had significantly more strong stress before identification of the malformation, as well as a clear tendency toward less appropriate timing of the pregnancy. Women with malformed offspring represent a psychosocially vulnerable group and should receive special clinical and personal support.

The relationship between health-state utilities and the SF-12 in a general population

It would be a major advance if quality-of-life instruments could be translated into health-state utilities. The aim with this study was to investigate the relationship between the SF-12 and health-state utilities, based on responses to a postal questionnaire sent to a random sample of 8,000 inhabitants, aged 20-84 years, in the general population. The questionnaire included the SF-12, a rating-scale (RS) question, and a time-tradeoff (TTO) question; the response rate was 68%. Age, gender, and the 12 items of the SF-12 were used as explanatory variables in a linear regression analysis of the health-state utilities. The regression models explained about 50% of the variance in the RS answers and about 25% of the variance in the TTO answers. Most of the SF-12 items were related to the health-state utilities in the expected ways, with especially strong results for the RS method. The results suggest that the SF-12 can be converted to health-state utilities, but that further work is needed to reliably estimate the conversion function.

The impact of over-the-counter availability of nasal sprays on sales, prescribing, and physician visits

OBJECTIVE

The aim was to study changes in sales and prescribing of nasal decongestants containing oxymetazoline or xylometazoline, changes in number of physician visits for rhinitis and sinusitis, and changes in public expenditures for physician visits due to the switch of these drugs from prescription to over-the-counter status in Sweden in 1989.

DESIGN

Retrospective registry study using the local sales statistics on medicines in the municipality of Tierp from The National Corporation of Swedish Pharmacies and the individual-based computerised registry in Tierp based on health care utilisation and drug use from the Centre for Primary Care. Analyses were carried out during the time period 1988-1995.

SETTING

The Swedish community of Tierp with about 20,000 inhabitants.

SUBJECTS

The population of Tierp.

MAIN OUTCOME MEASURE

Sales of nasal decongestants and dispensed prescriptions of nasal decongestants, physician visits for rhinitis and sinusitis, and public expenditures for these.

RESULTS

Sales of nasal sprays increased, while sales of nasal drops decreased. The number of dispensed prescriptions as well as physician visits decreased. The public expenditures estimated for physician visits decreased as well.

CONCLUSION

This study shows an increase in sales of nasal decongestants and a significant decrease in prescribing of nasal decongestants and the number of physician visits for rhinitis and sinusitis as well as the public expenditures estimated for these, after the switch from prescription to over-the counter status of nasal sprays in 1989.

A note on validating Wagstaff and van Doorslaer's health measure in the analysis of inequalities in health

The aim of this note is to validate Wagstaff and van Doorslaer's approach of constructing a continuous health measure to be used in the analysis of inequalities in health. We calculate health concentration indices for Uppsala County in Sweden based on three different health status measures: health measured according to the WvD approach based on a self-assessed categorical health measure, health measured by the rating scale method, and health measured by the time trade-off method. The concentration index does not differ significantly for the three health status measures, and our results thus support the validity of the WvD method.

Effects of user charges on the use of prescription medicines in different socio-economic groups

This study examined the sensitivity towards increases in user charges for different types of drugs and among different socio-economic groups. It was based on responses by 2008 consumers of prescription drugs to a self-administered postal questionnaire sent to a random sample of 8000 inhabitants in Uppsala County in Sweden. The questionnaire included a question about whether the respondents would use fewer prescription drugs if the user charges increased by a specific amount. The increase in user charges was varied between 9 and 150% in five different subsamples. Logistic regression analysis was used to estimate the probability that a respondent would reduce consumption of prescription drugs as a function of the size of the user charges increase, socio-economic characteristics and the type of drug used. Results showed that the price sensitivity decreased with increasing age, income, education and self-rated health status. Price sensitivity was highest for antitussives and lowest for climacteric drugs. If the user charges doubled, 40% of antitussives users would reduce their consumption whereas only 11% of climacteric drugs users would reduce their consumption. It is concluded that sensitivity to increases in user charges varied greatly between different types of drugs and between socio-economic groups. The young, those with poor health status, low education and low income are most likely to decrease consumption of prescription drugs when user charges increase.

Naturally occurring variants of human milk bile salt-stimulated lipase

Analysis of milk samples from a number of lactating women revealed molecular variants of bile salt-stimulated lipase (BSSL) of both lower and higher molecular mass than that commonly occurring. In contrast to previous observations, we report on individuals having only a variant of lower mass, both one of lower and one of common mass, or both one of lower and one of higher mass of the lipase. From two individuals we purified the lower molecular mass BSSL variant and characterized it. The amount of lipase in the milk of these two individuals was considerably less than average (mean of 10 women with BSSL of the most common molecular mass). The BSSL variant of lower mass showed the same bile salt activation, pH dependency, temperature stability as those most commonly occurring. We could localize the difference in mass to the large O-glycosylated repeat sequence close to the C-terminus of the protein. With respect to all characteristics studied, the BSSL variant of higher mass was also similar to that most commonly ocurring. Again, the difference in mass could be localized to the repeat region of the protein. Hence, it appears as if the repeat region, normally carrying 16 repeats of 11 amino acids each, varies in size between individuals.

Subunit G of the vacuolar proton pump. Molecular characterization and functional expression

The vacuolar type proton pump of clathrin-coated vesicles has a multisubunit ATP hydrolytic center that is peripheral to the membrane. Polypeptides present in this domain include the well characterized subunits A, B, C, D, E, and F; SFD, a dimer composed of 50- and 57-kDa polypeptides; and polypeptides termed G and H. Of these, subunits A, B, C, and E have been shown to be necessary but not sufficient for significant ATPase activity; in addition, either polypeptide G or H is also required for ATP hydrolysis (Xie, X.-S. (1996) J. Biol. Chem. 271, 30980-30985). In this study, the polypeptides G and H were purified and directly sequenced. Subsequent molecular analysis has revealed that these proteins are isoforms, which we designate G1 and G2. The cDNAs encoding the rat and bovine brain and chicken osteoclast forms of G1 have been cloned. The open reading frames of the rat and bovine clones encode hydrophilic proteins of 118 amino acids that differ at only five residues; bovine G1 has 36% identity with VMA10, a component of the proton channel of yeast. Northern blot analysis revealed a 1. 0-kilobase pair transcript encoding G1 in bovine brain, kidney, heart, and spleen. The cDNA encoding bovine polypeptide H was cloned and sequenced, revealing this protein to be 64% identical to G1, constituting isoform G2. In Northern blot analysis, a single 1. 7-kilobase pair transcript hybridized with a probe to G2 in brain, but not in heart, kidney, or spleen. An antibody against a bovine G1-specific domain reacts with V pump from bovine brain, kidney, and chromaffin granule, whereas an anti-G2 antibody reacts only with proton pump from brain. The bovine forms of G1 and G2 were subsequently expressed in Escherichia coli and Sf9 cells, respectively, and purified to homogeneity. Reconstitution of ATP hydrolysis was achieved by combination of recombinant subunits A, B, C, and E with either recombinant G1 or G2, demonstrating the role of these isoforms in pump function.

Recombinant human bile salt-stimulated lipase: an example of defective O-glycosylation of a protein produced in milk of transgenic mice

The expression of recombinant human bile salt-stimulated lipase (bssl) was targeted to the lactating mammary gland of transgenic mice. Expression of recombinant genes comprising bsslcDNA, or alternatively genomic bssl DNA, under control of regulatory elements derived from the murine whey acidic protein (wap) gene was achieved and evaluated. Constructs containing genomic bssl sequences mediated high levels (0.5-1 mg ml-1) of recombinant human BSSL in the milk. The recombinant BSSL produced was purified, biochemically characterized and compared to native BSSL and recombinant BSSL produced in mouse C127 and hamster CHO cells. Recombinant BSSL derived from transgenic mice showed a different migration and distribution after SDS-PAGE electrophoresis, lower apparent molecular mass on size-exclusion chromatography and no detectable interactions with a panel of lectins. These results indicate a significantly lower degree of O-glycosylation of recombinant BSSL in milk from transgenic mice than was found for the native enzyme or recombinant CHO- or C127 cell-produced BSSL. Despite these differences, mouse-milk-derived recombinant BSSL exhibited similar lipase activity, the same stability to low pH and similar sensitivity to elevated temperatures as the native enzyme. The observation that mouse-C127-cell-produced recombinant BSSL is heavily O-glycosylated makes species-related restrictions less attractive as an explanation for the reduced O-glycosylation.

Long-term experience of self-injection therapy with prostaglandin E1 for erectile dysfunction

A total of 42 evaluable patients 36-80 years old were treated with intracavernous injection of prostaglandin E1 for erectile dysfunction. They reported retrospectively via a questionnaire their long-term experience of this method. Twenty-four patients (57%) were after 46.9 months still using the technique, while 18 patients (43%) had abandoned the method after 21.4 months of use. No major complications were observed or reported.

Molecular cloning and characterization of the mouse carboxyl ester lipase gene and evidence for expression in the lactating mammary gland

DNA hybridization was used to isolate a 2.04-kb cDNA encoding carboxyl ester lipase (CEL) from a mouse lactating mammary gland, lambda gt10 cDNA library. The cDNA sequence translated into a protein of 599 amino acids, including 20 amino acids of a putative signal peptide. Comparison of the deduced amino acid sequence of the mouse CEL with CEL from five other species revealed that there is a high degree of homology between the different species. The mouse CEL gene was also isolated and found to span approximately 7.2 kb and to include 11 exons. This organization is similar to those of the recently reported human and rat CEL genes. We have also analyzed expression of the CEL gene in the mammary glands from other species by performing a Northern blot analysis with RNA from goat and cow. The results show that the gene is expressed in both species.

Recombinant human-milk bile-salt-stimulated lipase. Functional properties are retained in the absence of glycosylation and the unique proline-rich repeats

Human milk bile-salt-stimulated lipase ensures efficient utilization of milk lipid in breast-fed infants. The N-terminal two-thirds of the peptide chain is highly conserved and shows striking similarities to typical esterases. In contrast, the remaining C-terminal part consists of a unique sequence of 16 proline-rich O-glycosylated repeats of 11 residues each. Recently we could show, using recombinant lipase variants, that neither these repeats nor the single N-linked sugar chain are essential for catalytic efficiency. In the present study, we report on the lack of importance of glycosylation and the unique repeats for other important functional properties, i.e. bile-salt activation, heparin binding, heat stability, stability at low pH and resistance to proteolytic inactivation. Compared to native enzyme, recombinant full-length lipase produced in two mammalian cell lines differed slightly in glycosylation pattern with no effects on the functional properties. Moreover, a variant lacking all repeats and the C-terminal tail following the last repeat exhibited the same functional characteristics as purified native milk enzyme. Thus, the structural basis for all the typical and functionally important properties reside in the N-terminal conserved part, in spite of the fact that none of these properties are shared by typical esterases. We could however, demonstrate that the C-terminal repeats are responsible for the unusual behaviour of the enzyme in size-exclusion chromatography, resulting in a considerably higher than expected apparent molecular mass.

The prevalence of circulating anti-tubular basement membrane-antibody in renal diseases, and clinical observations

Anti-tubular basement membrane antibodies were determined by ELISA in 217 patients with different renal diseases. The assay for antibodies in serum was based on a 58 kD bovine tubular basement membrane antigen. Sera were studied from 69 patients with different forms of interstitial nephritis; 15 patients (10 women, 5 men) had anti-tubular basement membrane titers above the normal (compared with a reference group of healthy blood donors). Three patients are presented in greater detail. Thirty-four patients with pyelonephritis (confirmed by intravenous urogram) were investigated; one serum was positive. Sera from 114 patients with renal glomerular and/or vascular disease were studied; 12 had positive titers for tubular basement membrane and glomerular basement membrane or other kidney disease antibodies. This study supports the opinion that damage in the renal medulla can be caused by an autoimmune process. Circulating anti-TBM antibodies may be of value in the investigation of patients with tubulo-interstitial diseases but the cause and prognosis of this condition is, however, not known.

Backdiffusion or bicarbonate may stimulate complement activation during haemodialysis with low-flux membranes

Backdiffusion of dialysate during haemodialysis with low-flux membranes and the use of bicarbonate dialysatebase, may increase the risk for contamination. The influence on the complement system was studied by altering the flux of acetate or bicarbonate dialysate base across the membrane. Eight patients were dialysed with a transmembrane pressure of 100 mm Hg (group I) during the first 60 min to standardize the ultrafiltration (UF) and acetate as dialysate. In eight other patients (group II) the UF was "set at zero" ml during the first 60 min using an FCM 10-1 monitor (Gambro) and bicarbonate as base. The groups were dialysed three times on two hollow-fiber membranes made of Hemophan and cellulose acetate (CA). Blood samples were taken at 0, 15, 60 and 180 min, and analysed for plasma protein, haematocrit and complement C3d. In group II there was a reduction in plasma protein concentration at 15 and 60 min (p < 0.002) for Hemophan and at 60 min (p < 0.01) using CA. C3d was increased at 15 min for both filters (p < 0.03). The reduction of protein in group II was followed by changes in the haematocrit, indicating a backdiffusion of dialysate, which may contribute to the concomittant increase in C3d.

Recombinant human milk bile salt-stimulated lipase. Catalytic activity is retained in the absence of glycosylation and the unique proline-rich repeats

Human milk bile salt-stimulated lipase ensures efficient utilization of triacylglycerol by breast-fed infants. Cloning and sequencing of cDNA have revealed that the peptide chain consists of 722 amino acid residues showing only little homology to typical lipases. The sequence is identical to that of pancreatic carboxylic-ester hydrolase. The COOH-terminal part contains 16 proline-rich repeats of 11 residues with O-linked carbohydrate. The only N-linked sugar chain is situated close to the active-site serine. Using C127 cells and a bovine papilloma virus vector, high and stable expression of full-length lipase and of several variants, obtained by site-directed mutagenesis, was achieved. The produced proteins were purified and further characterized. Variants lacking all, or all but two, repeats were active with similar specific activity and the same bile salt dependence as the native milk enzyme. Changing the asparagine necessary for N-glycosylation gave the same principal results. Active recombinant full-length lipase was also produced in a bacterial system. We conclude that neither glycosylation (N- or O-linked) nor the proline-rich repeats are essential for catalytic activity or bile salt activation of human milk bile salt-stimulated lipase.

Circulatory basophilia in guinea pigs with delayed-type hypersensitivity. Topical antigenic provocation induces circulatory basophilia

Circulatory basophilia could be induced in inbred guinea pigs systematically immunized with ovalbumin and consequently provoked repeatedly with dissolved ovalbumin applied onto the mucosa of the nares or the outer eye. The degree of the increase in circulatory basophil granulocytes depended on the adjuvant used and was significantly more pronounced after immunization with Freund's complete adjuvant than with alhydrogel (Al(OH)3). The degree of basophilia was also dependent on the animal strain, but different in two strains selected for high-asthma trait.

Immunologically induced purulent anterior segment inflammation of the guinea pig eye

A single conjunctival application of ovalbumin to inbred guinea pigs (IMM/S 209) immunized with the same antigen in Freund's complete adjuvant provoked an acute purulent inflammation of the anterior segment of the eyes with a duration of up to 1 week. Intense conjunctival injection and chemosis were followed by a purulent discharge. A corneal haze was observed regularly, and a considerable proportion of the animals developed a pronounced pannus and corneal ulcers. Tear fluid cytology revealed a rapid increase in cell concentration, from the normal level (less than 10(8)/l) to greater than 10(11)/l. Seventy to 95% of the cells were polymorphonuclear leukocytes. Histological examination revealed an acute inflammatory reaction which radiated from the conjunctival fornices to the entire anterior segments of the eyes. The process was characterized by an intense oedema, vasodilation and perivascular aggregations of polymorphonuclear leukocytes, and to a lesser extent eosinophilic granulocytes which characteristically infiltrated and penetrated the epithelial layers. Neovascularization could be observed early after challenge in the stroma of all parts of the outer eye. Ulcerations of the conjunctival and corneal epithelia were observed frequently. After a number of reiterations of the antigenic challenge, a marked infiltration with lymphocytes and basophils/mast cells was observed, and significant scarring of the conjunctival mucosa developed. In several animals, a slight, but significant co-reaction of the contra-lateral, non-challenged eye was observed.

Genetic control of eosinophilia in guinea pig strains inbred for high or low bronchial allergic reactivity

Development of eosinophilia was studied in four strains of guinea pigs (gp), selectively bred for either high or low respiratory anaphylactic reactivity. One high-asthma strain (IMM/S 209) and one low-asthma strain (IMM/R 203) developed spontaneous high blood eosinophilia. The 2 other gp strains - one high-asthma strain (IMM/S 740) and one low-asthma strain (IMM/R 201-16) - maintained normal low levels of eosinophilic granulocytes (eos). The levels of eos in various tissues showed similar differences between the gp strains. Following immunization with ovalbumin/Al(OH)3 the levels of blood eos increased significantly only in gp of strain 209. The blood eos levels in gp of all 4 strains decreased significantly following immunization with ovalbumin in Freund's complete adjuvant (FCA).

Histamine-induced bronchoconstriction in conscious guinea pigs measured by strain-gauge transduction. A new method

A new objective method for measuring histaminedihydrochloride-induced bronchoconstriction in conscious guinea pigs has been developed. The aim of the present work was to investigate whether identical results could be obtained when the clinical observation of conscious guinea pigs with symptoms of respiratory distress (bronchoconstriction) was compared to an objective measuring technique of this parameter. An evaluation of the repeatability of the method was made and the respiration frequence (fR) and histaminedihydrochloride challenge concentration were compared to see whether there was a correlation between the two. Consequently, an apparatus was built that allowed simultaneous recording of breathing pattern and clinical observation of the animal being challenged. The breathing pattern was recorded by a strain-gauge transducer, connected to a measuring bridge, and the curves obtained on a jet ink x-y writer were used for calculating changes in duration of expiratory phase (Te) and fR. During the attacks of histaminedihydrochloride-induced bronchoconstriction a significantly prolonged Te could be calculated from the respiration curves. A high degree of agreement was found between this objective measure and clinically observed respiratory distress. The repeatability of the method was comparable to that of corresponding methods used for histaminedihydrochloride challenge in man. No obvious correlation was found between changes in fR and histaminedihydrochloride challenge concentration.