Repeated use of the emergency department: qualitative study of the patient's perspective

OBJECTIVE

To explore what lies behind repeated emergency department (ED) use, from the patients' own perspectives.

METHODS

Qualitative study based on in depth interviews with frequent users of the ED at the Huddinge University Hospital, Sweden. Ten adult patients having visited the ED 6-17 times in the previous 12 months were interviewed. The personal meaning they attached to the symptoms and their encounters at the ED were inductively analysed, thereby relating patient behaviour to life conditions.

RESULTS

The frequent ED visitors perceive pain or other symptoms as a threat to life or to personal autonomy. Irrespective of whether or not the patients relate their health problems to a traumatic event, overwhelming anxiety compels them to seek urgent help. Clear cut diagnoses are seldom mentioned. Although none of the patients is homeless or totally lacking in means, the narratives reveal struggles with adverse life circumstances and medical, psychological and/or social problems, including alcohol or other substance misuse. Occasional referrals from the ED to a psychiatrist seem not to lead to any continuous treatment or to a change in the patients' health seeking behaviour. Satisfaction with care becomes adversely affected when the patients perceive that the ED staff classifies their use of the ED as inappropriate or when their symptoms are belittled.

CONCLUSIONS

From their own perspectives, frequent ED visitors are in need of urgent care. It is particularly important to these patients that the personal meaning they attach to their symptoms is attended to and respected by the ED staff.

Genotypes of clustered cases of Pneumocystis carinii pneumonia

Reports of outbreaks of Pneumocystis carinii pneumonia (PCP) among human immunodeficiency virus-negative immunocompromised patients have suggested a person-to-person transmission of P. carinii. In this study, 17 bronchoalveolar lavage isolates from patients in 3 PCP outbreaks were genotyped, 2 in renal transplant recipients and 1 outbreak among patients with haematological disorders. Genotypes in the P. carinii sp. f. hominis (P. carinii f.sp. hominis) mt large subunit ribosomal RNA site 85 were detected by 2 methods: direct sequencing and 3 different allele-specific polymerase chain reaction assays. Although limited data on patient contacts were available, the detected P. c. hominis genotypes do not support person-to-person transmission as the predominant transmission route of P. carinii in humans.

Fluorescence correlation spectroscopy detects galanin receptor diversity on insulinoma cells

Fluorescence correlation spectroscopy (FCS) allows the study of interactions of fluorescently labeled ligand with receptors in living cells at single-molecule detection sensitivity. From the autocorrelation functions of fluorescence intensity fluctuations, the diffusion time of molecules through the confocal volume is analyzed, and from that, the molecular weights of free and bound molecules can be calculated. We have applied FCS to study the receptor diversity for the neuropeptide galanin (GAL) in cultured cells. FCS measurement of the fluorophore rhodamine-labeled GAL (Rh-GAL) has been performed in 0.2-fL confocal volume elements of the laser beam. The analysis of autocorrelation functions of Rh-GAL in solution above cells and at cell membranes demonstrates that the diffusion time of unbound Rh-GAL is 0.16 ms, whereas diffusion times of membrane-bound Rh-GAL are 22 and 700 ms. Because both of the diffusion times (22 and 700 ms) are much longer as compared to that of unbound Rh-GAL, they correspond to slow-diffusing complexes when Rh-GAL is bound to the cell membranes. Addition of excess nonlabeled GAL is accompanied by competitive displacement. Full saturation of the GAL binding is obtained at nanomolar concentrations. Scatchard analysis of binding data reveal one binding process, assuming one binding site per Rh-GAL (n = 1). On the other hand, the appearance of two diffusion times, 22 and 700 ms, suggests the existence of two subpopulations of GAL receptor complexes or two subtypes of GAL receptor not detected before. This makes an important point that FCS permits the identification of receptors, which were not possible to detect before by conventional binding techniques. The inhibitory effect of pertussis toxin on the GAL binding considers a G-protein-involved allosteric system, important for the clarification of essential steps in the G-protein-related signal transduction. This study is of pharmaceutical significance, since it will provide insights into how FCS can be used as a rapid technique for studying ligand-receptor interactions in living cells, which is one step forward for large-scale drug screening in cell cultures.

Clinical significance of nested polymerase chain reaction and immunofluorescence for detection of Pneumocystis carinii pneumonia

OBJECTIVE

To study the clinical significance of a nested polymerase chain reaction (PCR) method compared to immunofluorescence (IF) for detection of Pneumocystis carinii.

METHODS

The medical records of 89 patients with 91 episodes of pneumonia were scrutinised retrospectively. The pneumonia episodes were divided into categories according to the likelihood that the patient had had clinical Pneumocystis carinii pneumonia (PCP). All respiratory tract samples from the 89 patients (34 broncho-alveolar lavage (BAL) and 57 sputa) were tested for Pneumocystis carinii by IF and nested PCR.

RESULTS

Fifteen episodes, as diagnosed by IF, were classified as true PCP (combination of the groups with definite and probable PCP; sensitivity 60%, specificity 97%). Among the P. carinii DNA-positive episodes, detected with nested PCR, 24 were classified as true PCP (combination of the groups with definite and probable PCP; sensitivity 96%, specificity 59%), since all IF-positive samples were nested PCR positive. Only one pneumonia episode classified as a probable PCP, was negative with both methods, as applied to a BAL sample.

CONCLUSIONS

IF applied to BAL or sputum seems to be the most specific method for diagnosis of clinical PCP. Additional clinical cases can be found by nested PCR, although this then gives a high risk of detecting subclinical colonisation of P. carinii.

Frequent use of the hospital emergency department is indicative of high use of other health care services

STUDY OBJECTIVE

We sought to determine the proportion of emergency department patients who frequently use the ED and to compare their frequency of use of other health care services at non-ED sites.

METHODS

A computerized patient database covering all ambulatory visits and hospital admissions at all care facilities in the county of Stockholm, Sweden, was used. Frequent ED patients were defined as those making 4 or more visits in a 12-month period.

RESULTS

Frequent users comprised 4% of total ED patients, accounting for 18% of the ED visits. The ED was the only source of ambulatory care for 13% of frequent versus 27% of rare ED users (1 ED visit). Primary care visits were made by 72% of frequent ED users versus 57% by rare ED visitors. The corresponding figures for hospital admission were 80% and 36%, respectively. Frequent ED visitors were also more likely to use other care facilities repeatedly: their odds ratio (adjusted for age and sex) was 3.43 (95% confidence interval [CI] 3.10 to 3.78) for 5 or more primary care visits and 29.98 (95% CI 26.33 to 34.15) for 5 or more hospital admissions. In addition, heavy users had an elevated mortality (standardized mortality ratio 1.55; 95% CI 1.26 to 1.90).

CONCLUSION

High ED use patients are also high users of other health care services, presumably because they are sicker than average. A further indication of serious ill health is their higher than expected mortality. This knowledge might be helpful for care providers in their endeavors to find appropriate ways of meeting the needs of this vulnerable patient category.

The serotonin reuptake inhibitor fluoxetine reduces sex steroid-related aggression in female rats: an animal model of premenstrual irritability?

The aggressive behavior displayed by some (but not all) female Wistar rats when an unfamiliar rat is being introduced into their home cage (the resident intruder paradigm) was found to be higher in non-receptive phases (metestrus, diestrus) than in the receptive phases (proestrus, estrus) of the estrus cycle, and effectively reduced by ovariectomy. When removal of the ovaries was followed by administration of estradiol and progesterone, in a regimen mimicking the normal cyclical release of these hormones, aggressive behavior was elicited, two days after estrus, in animals that had displayed aggressive behavior before ovariectomy, but not in those that had not. Short-term administration of a serotonin reuptake inhibitor (fluoxetine hydrochloride; 10 mg/kg, i.p.; 4-5 days) reduced both the aggressive behavior displayed during the diestrus phase by normally cycling rats, and the aggressive behavior elicited by administration of estradiol plus progesterone after ovariectomy. It is suggested that the aggressive behavior displayed by the female Wistar rat in the resident intruder paradigm may serve as an animal model of premenstrual dysphoria.

Different domains in the third intracellular loop of the GLP-1 receptor are responsible for Galpha(s) and Galpha(i)/Galpha(o) activation

It has previously been shown that the GLP-1 receptor is primarily coupled to the adenylate cyclase pathway via activation of Galpha(s) proteins. Recent studies have shown that the third intracellular loop of the receptor is important in the stimulation of cAMP production. We have studied the effect of three synthetic peptide sequences derived from the third intracellular loop of the GLP-1 receptor on signal transduction in Rin m5F cell membranes. The whole third intracellular loop strongly stimulates both pertussis toxin and cholera toxin-sensitive G proteins, while the N-terminal half exclusively stimulates cholera toxin-sensitive G proteins and the C-terminal half only stimulates pertussis toxin-sensitive G-proteins as demonstrated by measurements of GTPase activity. These data confirm that the principal stimulatory G-protein interaction site resides in the third intracellular loop, but also suggest that the GLP-1 receptor is not only coupled to the Galpha(s) but also to the Galpha(i)/Galpha(o) type of G proteins and that distinct domains within the third intracellular loop are responsible for the activation of the different G-protein subfamilies.

Promiscuity in sand lizards (Lacerta agilis) and adder snakes (Vipera berus): causes and consequences

We review postcopulatory phenomena in the Swedish sand lizard (Lacerta agilis) and adder (Vipera berus), and in particular, links between female promiscuity, determinants of paternity, and offspring viability. In both species, females mate multiply and exhibit a positive relationship between the number of partners and offspring viability. We conclude that this relationship is most likely the result of variable genetic compatibility between mates arising from postcopulatory phenomena, predominantly assortative fertilization with respect to parental genotypes. However, males who were more successful at mate acquisition were also more successful in situations of sperm competition, suggesting a possible link between male (diploid and haploid) genetic quality per se and probability of fertilization. Neither the number of partners nor the number of matings influenced the risk of infertility in sand lizards, suggesting that selection for reduced risk of infertility is not a sufficient explanation for maintaining female promiscuity in this population. Finally, we conclude that the relatively low genetic variability exhibited by our study populations may have facilitated detection of genetic benefits compared to more outbred ones. However, recent work derived from outbred populations in other taxa suggest a greater generality of the principles we discuss than previously may have been appreciated.

Laparoscopy reduces unnecessary appendicectomies and improves diagnosis in fertile women. A randomized study

BACKGROUND

The aim of this study was to study the value of diagnostic laparoscopy prospectively in fertile women scheduled for acute appendectomy.

METHODS

For this study, 110 women, with acute abdominal pain ages 15 to 47 years, in whom the surgeon had decided to perform an appendectomy, were randomized to either open appendectomy or diagnostic laparoscopy, then open appendectomy if necessary.

RESULTS

Appendicitis was diagnosed in 66% of the women after open surgery, and in 73% after laparoscopy. During laparoscopy, was appendicitis misdiagnosed in only 7% of the women, from whom the appendix unnecessarily removed, whereas 34% in the open surgery group had a healthy appendix removed. No appendicitis was missed in the laparoscopic group. The relative risk of removing a healthy appendix in open surgery was 6.6 relative risk (range, 2-21 C.I.) as compared with laparoscopy. Among the women with a healthy appendix, a gynecologic diagnosis was found in 73% after laparoscopy, as compared with 17% after open surgery.

CONCLUSIONS

Laparoscopy reduces unnecessary appendectomies and improves diagnosis in fertile women.

The otter (Lutra lutra) in Sweden--population trends in relation to sigma DDT and total PCB concentrations during 1968-99

Polychlorinated biphenyl (PCB) has been suggested as the major cause of the European otter (Lutra lutra) population decline. This study investigates temporal and geographical changes in otter numbers as well as total PCB and sigma DDT concentrations in otters and their food in different parts of Sweden with various pollution impacts during three decades. In Sweden, rare species belong to the State and carcasses of such specimens are sent to the authorities. Two-hundred and eight specimens have been used to investigate temporal and spatial variation in the otter populations during 1968 and 1999. One-hundred and twenty-five of them have been chemically analysed. The population trends in northern Sweden coincide with the temporal trends of the contaminants. When concentrations of PCBs decrease in the environment, otter population increases. Neither aldrin/dieldrin nor mercury pollution seem to explain why the Swedish otter populations decreased dramatically during the 1960s-1980s. In southern Sweden total PCB concentrations are still high and the indications of improvement of the population are weak.

Testosterone, ticks and travels: a test of the immunocompetence-handicap hypothesis in free-ranging male sand lizards

The immunocompetence-handicap hypothesis suggests that androgen-dependent male characters constitute honest signals of mate and/or rival quality because of the imposed costs through immune suppression associated with elevated testosterone levels. We demonstrate in a field experiment that male sand lizards (Lacerta agilis) exposed to elevated testosterone suffered from increased mass loss and tick load compared to control males. Although the first of these two results could be due to an elevated basal metabolic rate from increased plasma testosterone levels, the increased parasite load was statistically independent of the loss in body condition and is likely to be due to compromised immune function. Testosterone-treated males showed greater mobility than control males, and greater mobility resulted in higher mating success. Our experiment thus lends support to the immunocompetence-handicap hypothesis, suggesting that male testosterone levels have been moderated by balancing selection for reproductive success and sustained immune function.

[Atrial septal defect--catheter-based closure now feasible!]

Atrial septal defects (ASD) of hemodynamic significance are usually treated surgically in early childhood. However, many cases will not be detected until the patient has become an adult. As there is a risk of development of pulmonary hypertension and tachyarrythmia in hemodynamically significant defects, closure is necessary. Although surgery is considered a safe procedure with very low perioperative mortality, there is a risk of complications and prolonged hospitalization, and postoperative convalescence is two months. Today we are able to offer patients with ASD of the secundum type an alternative treatment using catheter technique. The devices used are self expanding and easy to deploy, with a high success rate and low complication rate. Post-procedural convalescence is two days.

Differential expression of mouse laminin gamma2 and gamma2* chain transcripts

Laminins are large heterotrimeric basement membrane proteins that consist of alpha, beta, and gamma chains. We have previously shown that the human gamma2 and gamma2* transcripts result from the alternative use of the LAMC2 gene 3'-end exons. To explore the biological significance of the alternative gamma2 transcripts, we isolated the cDNA coding for the mouse laminin gamma2* transcript, characterized the 3'-end of the murine LAMC2 gene, and studied the expression of alternative gamma2 transcripts in several mouse tissues. The sequence reported here is the first one containing a full-length gamma2* 3'-UTR from any species. The mouse gamma2* transcript is 4110 bases and encodes a putative polypeptide of 1110 amino acids. This polypeptide lacks the C-terminal cysteine residue thought to be important for heterotrimer formation. The mouse gamma2* transcript was found to be expressed in several tissues by polymerase chain reaction (PCR), but at very low levels. The clearest signals were obtained on embryonic day 7, and in heart and testis of adult tissues. When the laminin gamma2* transcript expression pattern was compared with that of the gamma2 chain, a similar tissue distribution was observed. There was, however, a significant difference in expression levels. The longer gamma2 transcript was found to be much more abundant than the shorter gamma2* variant. Moreover, by whole-mount in situ hybridization, the shorter gamma2* form was localized in the mesenchyme of the developing kidney whereas the longer gamma2 form was exclusively present in the epithelium of the Wolffian (nephric) duct and ureteric bud. The results indicate different functions for the gamma2 variants.

cDNA cloning and embryonic expression of mouse nuclear pore membrane glycoprotein 210 mRNA

BACKGROUND

In embryonic kidneys, mesenchymal cells convert into epithelium in response to an induction by the tip of the ureter bud. Metanephric mesenchyme can also be induced to convert into epithelium in vitro. It is a model system to identify genes that could be important for epithelial development.

METHODS

By differential screening of a cDNA library made from mesenchymes induced in transfilter cultures by embryonic spinal cord for 24 hours, we selected cDNA clones representing genes that were preferentially expressed in 24-hour-induced mesenchyme and not in uninduced mesenchyme. The sequence of one clone was determined and used to obtain the sequence of a complete open reading frame. By Northern blotting and in situ hybridization, the expression of the mRNA in embryonic kidneys was determined.

RESULTS

We report the sequence and expression pattern of a marker for the 24-hour-induced state, mouse nuclear pore membrane glycoprotein 210 (mPOM210). The deduced 1886 amino acid sequence shows a 95% identity to the sequence of rat gp210. Northern blotting revealed a single 7.5 kb mRNA in 24-hour-induced mesenchyme, whereas message levels were fourfold to fivefold lower in uninduced mesenchyme. In situ hybridization of in vivo development confirmed the preferential expression of mPOM210 in epithelial cells. In the kidney, expression was seen in both the epithelium derived from the ureteric tree and the mesenchyme-derived epithelium. In other tissues of 13-day-old embryos, expression was also confined to the epithelium. In nervous tissues, the olfactory epithelium and walls of the lateral ventricle were the most prominently stained. Weak expression was seen in the heart.

CONCLUSIONS

mPOM210 mRNA is an early marker for developing epithelial cells. Furthermore, our results suggest that nuclear pore membrane proteins could be more cell-type specific than previously anticipated.

Increased luminal nitric oxide concentrations in the small intestine of patients with coeliac disease

BACKGROUND

Inflammation is known to be associated with enhanced nitric oxide production. A role for nitric oxide in coeliac disease has been suggested because of increased expression of the inducible isoform of nitric oxide synthase in the small intestine of patients with untreated coeliac disease.

DESIGN

During small bowel endoscopy in 11 control subjects, 10 patients with untreated coeliac disease and seven patients with treated coeliac disease, gas was aspirated from different parts of the upper gastrointestinal tract and immediately analysed using a chemiluminescence technique. Luminal nitric oxide concentrations were also quantified in 13 control subjects who had undergone colonoscopy.

RESULTS

Jejunal luminal nitric oxide concentrations were more than 20 times higher in patients with coeliac disease than in normal control subjects (mean 755 +/- 173 ppb, range 215-1690 ppb, vs. mean 31 +/- 9 ppb, range 1-83 ppb, P < 0.001). Jejunal luminal nitric oxide levels in patients with treated coeliac disease (mean 54 +/- 18 ppb, range 3-126 ppb) did not differ from those of control subjects.

CONCLUSIONS

This study shows that intraluminal jejunal nitric oxide concentrations are significantly increased in patients with untreated active coeliac disease.

[Oats can be included in gluten-free diet]

In the management of coeliac disease, it has been widely accepted that oats must also be excluded from the diet, along with wheat, rye and barley. The article consists in a review of published reports, and an account of our experience of including oats in the gluten-free diets of adults. Oats were found to be safe and well tolerated by adults with coeliac disease and dermatitis herpetiformis, though the risk of wheat contamination of commercial oat products remains a cause of concern. Similar findings were reported from a study of adolescents, but no such studies have been made of small children. Thus, the inclusion of oats, known to be a fibre-rich, naturally gluten-free food, would broaden the range of foodstuffs tolerable to coeliac patients, though for safety reasons they should be used only by adults until more information is available.

A parametric estimation procedure for relapse time distributions

In a relapse clinical trial patients who have recovered from some recurrent disease (e.g., ulcer or cancer) are examined at a number of predetermined times. A relapse can be detected either at one of these planned inspections or at a spontaneous visit initiated by the patient because of symptoms. In the first case the observations of the time to relapse, X, is interval-censored by two predetermined time-points. In the second case the upper endpoint of the interval is an observation of the time to symptoms, Y. To model the progression of the disease we use a partially observable Markov process. This approach results in a bivariate phase-type distribution for the joint distribution of (X, Y). It is a flexible model which contains several natural distributions for X, and allows the conditional distributions of the marginals to smoothly depend on each other. To estimate the distributions involved we develop an EM-algorithm. The estimation procedure is evaluated and compared with a non-parametric method in a couple of example based on simulated data.

Tooth-implant and implant supported fixed partial dentures: a 10-year report

PURPOSE

The use of implants for prosthetic rehabilitation of partially edentulous patients is increasing. However, the possibilities of placing implants in the posterior part of the mandible are often limited. The purpose of this longitudinal study with 10 years of follow-up was to evaluate the use of short implants supporting fixed partial dentures (FPD) in the posterior part of the mandible, and to compare implant supported FPDs to tooth-implant supported FPDs.

MATERIALS AND METHODS

The patient material comprised 23 patients with residual mandibular anterior teeth, and each patient received FPDs unilaterally. On one side the FPD was supported by two implants, and on the other side by one implant and one tooth, thus permitting intraindividual comparison. The distribution of the two types of FPDs in each jaw was randomized. Implant success rates, marginal bone changes, and mechanical complications were studied.

RESULTS

The tooth-implant connection did not demonstrate any negative influences on the overall success rates for the 10-year period, nor were the shorter implants found to be less favorable.

CONCLUSION

It is suggested that a prosthetic construction supported by both a tooth and an implant may be recommended as a predictable and reliable treatment alternative in the posterior mandible.

Presence of oxidized low density lipoprotein in nonrheumatic stenotic aortic valves

The aim of the present study was to analyze if LDL particles trapped in stenotic aortic valve tissue undergo oxidative modification. Degenerative aortic stenosis affects >3% of the population >75 years of age in the Western world. Recent studies have revealed the presence of a chronic inflammatory process similar to what has been described in other degenerative diseases such as atherosclerosis. However, the underlying disease mechanisms of degenerative aortic stenosis still remain largely unknown. Six tricuspid stenotic valves, obtained at valve replacement, were compared with 3 control valves collected from hearts taken out during transplantation. The stenotic valves and the control valves were examined by immunohistochemistry, using antibodies against apoB, 4-hydroxynonenal-modified LDL, leukocytes, and HLA-DR. All valves were also stained with oil red O for neutral lipids. Extracellular neutral lipids were found in all stenotic valves, extending from the bases along the fibrosa layer. This lipid colocalized with apoB- and 4-hydroxynonenal-modified LDL immunoreactivity. 4-Hydroxynonenal-modified LDLs were present around calcium deposits, subendothelially, and in the deeper layer of the fibrosa. There was also a colocalization with macrophages, T lymphocytes, and HLA-DR expression. Control valves had a thin area of neutral lipid accumulation, a small amount of apoB, but no signs of inflammation. A distinct colocalization between oxidized LDLs, T-lymphocyte accumulation, and calcium deposits suggests that oxidized lipids may play a role in the disease process.

[Pneumocystis carinii is still a dangerous opportunist. The infection is continuously a threat to immunocompromised patients]

Despite recent decrease in the incidence of Pneumocystis carinii pneumonia (PCP) among patients infected with HIV (human immunodeficiency virus), PCP remains a threat to other categories of immunocompromised patients. The article provides an outline of recent, mainly molecular genetic, findings in P. carinii research, including its new classification as a primitive fungus, host specificity and verified de novo infection in HIV-infected subjects. As the pathogen still defies propagation in vitro, laboratory diagnosis is dependent on microscopic demonstration of the organism. Diagnostic specificity can be enhanced by generating specific PCR (polymerase chain reaction) products which can be sequenced for genotyping. Findings in animal studies and epidemiological observations (e.g., in outbreaks of PCP among immunocompromised hospital patients), suggest transmission of PCP infection to be airborne. Genetic methods have been used to study the mode of P. carinii transmission. Nucleic acids of the human form of P. carinii (P. carinii f. sp. hominis) have been detected in the air of hospital wards, indicating susceptible patients to be at risk. By contrast, findings obtained with the same methods in studies of person-to-person transmission of P. carinii among clustered cases of PCP in hospitals suggest infection to be environmentally acquired. Thus, many questions remain to be answered regarding the occurrence and transmission of P. carinii infection.

Successful extracorporeal membrane oxygenation in four children with malignant disease and severe Pneumocystis carinii pneumonia

BACKGROUND

Toxic deaths due to intensified treatment are of increasing concern in view of the generally improved prognosis for children with malignancies. Pneumocystis carinii pneumonia (PCP) during immunosuppressive treatment in children with malignancies is a severe complication with a poor prognosis if mechanical ventilation is required. Extracorporeal membrane oxygenation (ECMO) is a recognized technique that provides temporary respiratory support for patients with intractable respiratory failure.

PROCEDURE

We here report successful ECMO support in four children with PCP, secondary to chemotherapy-induced immunosuppression, in whom the respiratory situation deteriorated despite pharmacological treatment and mechanical ventilation. The duration of ECMO was 7-43 days.

RESULTS

Three children with acute lymphoblastic leukemia recovered from their PCP to continue chemotherapy and are now in complete continuous remission. Their pulmonary function normalized completely during 6-12 months after ECMO therapy. One child with a primitive neuroectodermal tumor survived the PCP and was off ECMO for 11 days before succumbing to unrelated complications.

CONCLUSIONS

We conclude that ECMO offers an important means of respiratory support in children with severe PCP that can also be adopted during treatment for malignant disease.

[A survey of "heavy consumers" of emergency care services in Stockholm. Six per cent of the patients accounted for a quarter of emergency consultations]

A small subgroup of patients accounts for a substantial proportion of emergency room (ER) consultations. Of the 479,956 consultations at ER facilities at Stockholm hospitals in 1996, a quarter were accounted for by six per cent of the patients, a subgroup characterised by at least four ER consultations during the year. Some 1,500 patients consulted 12-233 times. Analysis of the care-seeking habits of five extremely heavy ER-facility consumers showed them also to be heavy consumers of other health care services such as primary and tertiary facilities. Since previous studies have shown heavy ER-facility consumers to be a vulnerable subgroup both medically and socially, co-ordination and planning of their care might well be beneficial.

Development and preliminary application of a new scale for assessing dysfunctional working models of self and others (DWM-S) in severely disturbed patients

Although several suggestions have been made concerning the content and characteristics of cognitive/emotive schemata held by people with different disorders, there is still a scarcity of suitable instruments for verifying or measuring such constructs. This is particularly true of schemata postulated to be present in patients with personality disorders or a schizophrenic disorder. This article deals with the development of a new scale for assessing dysfunctional internal working models of self and others (DWM-S) in psychiatric patients. Preliminary results obtained in a sample of patients (n=110) and healthy subjects (n=40) suggest that the scale has a highly satisfactory internal consistency (Cronbach's alpha=0.97), and satisfactory test-retest reliability (rho coefficient=0.90 in healthy subjects and 0.86 in patients). Moreover, the DWM-S is able to discriminate between patients and healthy subjects and between patients suffering from various disorders. Further studies are in progress to assess the cross-national generalizability of the findings obtained so far.

A second European collaborative study on polymerase chain reaction for Toxoplasma gondii, involving 15 teams

In order to investigate the accuracy and practicability of the polymerase chain reaction (PCR) in the antenatal diagnosis of congenital toxoplasmosis, a collaborative study involving 15 European laboratories was performed under the auspices of the Biomed 2 Programme of the European Community. Each team received 12 aliquots (four negative, eight positive) of 'artificial samples' made of amniotic fluid spiked with tachyzoites of the RH strain of Toxoplasma gondii. Each team performed its own PCR protocol (all were different). Nine of the 15 laboratories were able to detect a single parasite, but two of the 15 found all samples negative. Four of the 15 laboratories found one or more control samples to be falsely positive. This study highlights the lack of homogeneity between PCR protocols and performance and underlines the need for an external quality assurance scheme which could provide 'reference' samples that could be used by any laboratory wanting to establish and maintain an accurate diagnostic test based on PCR.

Incorporation and glial differentiation of mouse EGF-responsive neural progenitor cells after transplantation into the embryonic rat brain

In vitro, epidermal growth factor (EGF)-responsive neural progenitor cells exhibit multipotent properties and can differentiate into both neurons and glia. Using an in utero xenotransplantation approach we examined the developmental potential of EGF-responsive cells derived from E14 mouse ganglionic eminences, cortical primordium, and ventral mesencephalon, after injection into the E15 rat forebrain ventricle. Cell cultures were established from control mice or from mice carrying the lacZ transgene under control of the promoters for nestin, glial fibrillary acidic protein (GFAP), or myelin basic protein (MBP). The grafted cells, visualized with mouse-specific markers or staining for the reporter gene product, displayed widespread incorporation into distinct forebrain and midbrain structures and differentiated predominantly into glial cells. The patterns of incorporation of cells from all three regions were very similar without preference for the homotopic brain areas. These results suggest that EGF-responsive progenitor cells can respond to host derived environmental cues, differentiate into cells with glial-like features, and become integrated in the developing recipient brain.

Region-specific migration of embryonic glia grafted to the neonatal brain

Cell fate determination and region-specific migration among neurons from the developing brain have been widely studied. Because similar attributes have been mostly unexplored in reference to glia, the present study has characterized the migratory responses of glia from diverse regions of the embryonic mouse brain after their transplantation to the brains of early postnatal (still developing) rats. Through the use of the mouse-specific, glial-specific marker M2, immunocytochemical processing of host tissues three to four weeks after transplantation revealed notable difference in the migratory patterns of phylogenetically diverse populations of glia. While glia from the ventral mesencephalon, cerebral cortex, and cerebellar neuroepithelium all showed a similar affinity for the nigropallidal tract after grafting to the internal capsule, only ventral mesencephalon-derived glia showed restricted migration toward and into the substantia nigra after transplantation to the thalamus or pontine tegmentum. These results suggest the presence of a highly favourable substrate for glial migration along developing fibre tracts, but, more importantly, indicates the potential for certain glia to respond to particular (region-specific) distal cues within the developing brain.

Early specification of striatal projection neurons and interneuronal subtypes in the lateral and medial ganglionic eminence

The striatum is thought to be generated from two transient swellings in the ventral telencephalon, the lateral and medial ganglionic eminences, present at mid-stages of embryonic rat development. We have studied the relative contribution of these structures to the specific generation of striatal neuronal subtypes such as projection neurons and cholinergic and somatostatin-containing interneurons at an early stage and a mid stage in striatal neurogenesis. Dissociated progenitors isolated from the embryonic day 12.5 and embryonic day 15.5 rat lateral ganglionic eminence grafted into the previously ibotenic acid lesioned adult striatum, produce grafts containing extensive numbers of neurons expressing messenger RNA for the striatal projection neuron marker, DARPP-32, whereas grafts of the embryonic day 12.5 and embryonic day 15.5 medial ganglionic eminences do not. While preprosomatostatin messenger RNA-expressing neurons were observed in grafts from each of the lateral ganglionic eminence and medial ganglionic eminence at both embryonic day 12.5 and embryonic day 15.5, choline acetyltransferase messenger RNA-expressing cholinergic neurons were largely found in grafts derived from the embryonic day 12.5 medial ganglionic eminence. These results suggest that the neuronal diversity of the adult striatum may derive both from the lateral ganglionic eminence, providing DARPP-32-expressing projection neurons as well as somatostatin-containing interneurons, and the early stage medial ganglionic eminence specifically contributing the cholinergic interneurons.

Identification of Pneumocystis carinii f. sp. hominis gene sequences in filtered air in hospital environments

To evaluate the risk of a nosocomial spread of Pneumocystis carinii f. sp. hominis (P. carinii hominis), air filter samples from rooms of P. carinii pneumonia (PCP) patients, adjacent corridors, and other hospital environments have been investigated for the presence of P. carinii hominis. Amplified DNA from air filters and sputum or bronchoalveolar lavage samples from the PCP patients have been genotyped with the P. carinii hominis genes of the mitochondrial large-subunit (mtLSU) rRNA and the internal transcribed spacers (ITS1 and ITS2) of the rRNA. Genotypes of the two loci were identified by direct sequencing, and for site 85 of the mtLSU locus, three allele-specific PCR assays were used. P. carinii hominis DNA was identified in the air of five of seven PCP patient rooms and in the air of two of four air filtrations from the ward corridors. The P. carinii hominis genotypes were the same in four of the five room air samples as those in the corresponding patients, suggesting a risk of person-to-person transmission of P. carinii hominis from PCP patients. Three of 16 air samples collected in infectious disease wards without the presence of PCP patients and one sample from a cardiology unit in a separate hospital building were also positive, which further strengthens the possibility of acquisition of P. carinii hominis from the environment.

Update on Pneumocystis carinii f. sp. hominis typing based on nucleotide sequence variations in internal transcribed spacer regions of rRNA genes

Pneumocystis carinii f. sp. hominis isolates from 207 clinical specimens from nine countries were typed based on nucleotide sequence variations in the internal transcribed spacer regions I and II (ITS1 and ITS2, respectively) of rRNA genes. The number of ITS1 nucleotides has been revised from the previously reported 157 bp to 161 bp. Likewise, the number of ITS2 nucleotides has been changed from 177 to 192 bp. The number of ITS1 sequence types has increased from 2 to 15, and that of ITS2 has increased from 3 to 14. The 15 ITS1 sequence types are designated types A through O, and the 14 ITS2 types are named types a through n. A total of 59 types of P. carinii f. sp. hominis were found in this study.

In utero gene transfer reveals survival effects of nerve growth factor on rat brain cholinergic neurones during development

Nerve growth factor (NGF) is a maintenance factor for cholinergic neurones in the brain, but its properties as a developmental survival factor are largely unknown. The low accessibility of the developing mammalian brain to experimental manipulation makes it difficult to increase NGF levels during the early phases of brain development. In the present study we have used an in utero, ex-vivo gene transfer approach to explore NGF actions during development of the cholinergic system in the rat brain. Significantly increased numbers of cholinergic neurones were found only in the mesopontine complex in animals receiving NGF-secreting transplants, whereas the cholinergic neurones in the basal forebrain and striatum were not clearly affected. The present results suggest that overexpression of NGF during development may promote the survival of distinct populations of central cholinergic neurones into adulthood.

Incorporation of mouse neural progenitors transplanted into the rat embryonic forebrain is developmentally regulated and dependent on regional and adhesive properties

During development, telencephalic neural progenitors acquire positional specification and give rise to distinct structures such as the striatum and cortex. Here, we examine, in vivo, the influence of developmental stage, cell-surface molecules and regional differences along the dorso-ventral and antero-posterior axes on the selective incorporation of neural progenitors derived from different regions of the developing brain, utilizing a cross-species in utero transplantation paradigm. Striatal progenitors derived from the embryonic day (E) 12-14 mouse lateral ganglionic eminence (LGE) were observed consistently to incorporate into the developing striatum as early as 24-48 h following intraventricular injection into the E15-17 rat host. By removing cell-surface molecules from the LGE progenitors, the pattern of incorporation was remarkably different with no preferential striatal incorporation. Cortical progenitors with intact cell-surface molecules, by contrast, displayed little telencephalic (including striatal) incorporation as compared with precursors from the LGE. However, both progenitors from cortex and LGE incorporated widely into diencephalic and mesencephalic structures. The capacity for integration of precursors derived from the LGE and cortex gradually decreased during development of the host and was minimal in the postnatal day (P) 1 host. Unlike the telencephalic precursors, the vast majority of progenitors derived from the midbrain and cerebellar primordium (with cell-surface molecules intact) incorporated into diencephalic and midbrain nuclei with only a few cells observed in the telencephalon. These results demonstrate that incorporation of neural progenitors across the ventricular wall in the embryonic host is strictly developmentally regulated, dependent on their position along the antero-posterior axes and in the case of progenitors from the LGE is mediated by cell-surface molecules expressed on the transplanted cells.

Temporal trends of organochlorines in Northern Europe, 1967-1995. Relation to global fractionation, leakage from sediments and international measures

The time trend monitoring of organochlorine pollution was carried out in Sweden since the late 1960s. This report presents data on concentrations of DDT, PCB, HCHs and HCB in biota samples collected and analysed annually. All the matrices and compounds studied show a significant decrease over time. The data cover severely polluted Swedish marine and fresh water in southern Sweden as well as locally unpolluted waters in remote northern Arctic regions of Sweden. A total of 13 time series representing different locations and species are presented for the different pollutants. The period studied covers the time when pollution was serious as well as the time of recovery. All monitoring activities were carried out at the same laboratories over the entire study period, which means that comparability over time is good in the sets of data presented. The various time trends show a convincing agreement with trends and annual change over time, although the concentrations differ between the species and locations investigated, the highest concentrations being in the south. Since the annual changes are normally similar regardless of locations and species, spatial variations in concentrations remain over time, although concentrations are lower today. The onset of changes in concentrations over time can be related to international measures or other circumstances that lowered releases into the environment. Similarities in the annual changes, as well as the time when changes began, are discussed with respect to suggested hypotheses on the fate of the investigated organochlorines. It was not possible to verify that the oxygenation of anoxic sediments mobilised old pollution in Baltic sediments. Neither was it possible to conclude that eutrophication has caused a measurable effect on the rate and timing of the decreases. Finally, long-range transport to Arctic regions seems to be due more to a one step transport than to the 'Grass-hopper' effect. The comprehensive database used, clearly shows how important it is to have datasets big enough to describe between-year variation before attempting to evaluate the time trend. In addition, if between-year variation is not known, it is then also difficult to evaluate spatial variation on the basis of single year observations.

Intrathecal sufentanil compared with epidural bupivacaine analgesia in labour

Epidural analgesia for pain relief during labour has certain disadvantages including slow onset. However, intrathecal sufentanil provides rapid onset and well-controlled analgesia lasting 1-4 h. The aim of this study was to compare the analgesia and the side effects of intrathecal sufentanil with epidural bupivacaine during labour. In a randomized, double-blind and controlled trial 58 parturient women requesting analgesia during labour were studied. The patients received either intrathecal sufentanil 10 micrograms and epidural saline, or intrathecal saline and epidural bupivacaine 20 mg. Visual analogue scores (VAS) for pain, blood pressure, heart rate, respiratory rate, level of sedation and the incidence of pruritus and nausea were recorded. Pain scores were significantly lower between 5 and 90 min after injection in patients receiving intrathecal sufentanil. Pruritus was significantly more frequent among those receiving intrathecal sufentanil. The rapid onset and effective analgesia of intrathecal sufentanil may in certain situations be advantageous.

Efficient adenovirus-mediated gene transduction of normal and leukemic hematopoietic cells

We evaluated the efficiency of adenovirus-mediated gene transfer into normal and malignant human hematopoietic cells. An E-1 and E-3 deleted, replication-defective recombinant Ad.RSV beta gal vector was used and the transduction efficiency was studied at a multiplicity of infection of 13 p.f.u. per cell. Approximately 40-50% of normal monocytes were transduced, whereas purified normal resting T cells and B cells were resistant to infection. We showed that 50-80% of primary chronic myeloid leukemia cells (CML, n = 12) were efficiently transduced in contrast to CML, successful transduction of resting primary chronic B lymphocytic leukemia cells required appropriate preactivation of targeted cells. A novel protocol for the efficient transduction of adenovirus into B-CLL cells was presented. We showed that anti-CD40 mAb or CD40 ligand acts in synergy with rhIL-4 to enable the transduction of approximately 50-75% of B-CLL cells (B-CLL, n = 6). Expression of beta-galactosidase in transduced CML cells and B-CLL cells was detected for at least 15 days after transduction. The present studies underline the utility of adenovirus vectors for the construction of cytokine gene-modified tumor vaccines for the treatment of hematopoietic malignancies such as CML and B-CLL.

Specification of mouse telencephalic and mid-hindbrain progenitors following heterotopic ultrasound-guided embryonic transplantation

We have demonstrated the utility of ultrasound backscatter microscopy for targeted intraparenchymal injections into embryonic day (E) 13.5 mouse embryos. This system has been used to test the degree of commitment present in neural progenitors from the embryonic ventral telencephalon and mid-hindbrain region. Many E13.5 ventral telencephalic progenitors were observed to integrate and adopt local phenotypes following heterotopic transplantation into telencephalic or mid-hindbrain targets, whereas mid-hindbrain cells of the same stage were unable to integrate and change fate in the telencephalon. In contrast, many mid-hindbrain cells from an earlier developmental stage (E10.5) were capable of integrating and adopting a forebrain phenotype after grafting into the telencephalon, suggesting that mouse mid-hindbrain progenitors become restricted in their developmental potential between E10.5 and E13.5.

Microsatellites in the sand lizard (Lacerta agilis): description, variation, inheritance, and applicability

We developed microsatellite markers for the sand lizard (Lacerta agilis) to enable investigations of the genetic variability within and among populations with a heterogeneous spatial distribution in Sweden. The populations, which could not be characterized by variation in allozymes or mitochondrial DNA, had a substantial level of variability in microsatellite loci. However, the variability in Swedish populations was limited compared to a large, outbred Hungarian population. In the sand lizard, the number of (GT/CA)n repeats was approximately three times higher than that for (CT/GA)n. The number of repeats and the frequency of microsatellites were within the range reported for other species. Three of nine microsatellite loci showed alleles that could not be amplified, which is in agreement with recent reports describing microsatellite "null alleles" as a common occurrence. We discuss the caution which this calls for when calculating paternity probabilities and when estimating between-population allelic differentiation. A potential problem with different mutation rates for alleles within the same locus is discussed.

Mk II: the self-tapping Brånemark implant: 5-year results of a prospective 3-center study

The 5-year result of a prospective 3-center study is presented, comprising 103 patients with 288 Mk II self-tapping and 275 standard implants of the Brånemark System. Out of 363 mandibular and 200 maxillary fixtures, one Mk II was lost of the lower jaw and 13 of each implant type failed in maxillae during the study period. Cumulative prosthesis stability was 97%. Five patients accounted for more than 85% of the fixture losses. Marginal bone resorption was similar for both implant designs. Apart from the implant failures and one patient exhibiting disturbed nerve sensation of the mental nerve, no major complications were encountered. Overall, this study revealed equal cumulative success rates for standard and Mk II implants after 5 years of observation. Mandibular implants exhibited greater success rates (100%) for both tested implant types compared to maxillary implants (87%).