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Gamma-secretase is an enzyme complex that mediates both Notch signaling and beta-amyloid precursor protein (APP) processing, resulting in the generation of Notch intracellular domain, APP intracellular domain, and the amyloid beta peptide (Abeta), the latter playing a central role in Alzheimer disease (AD). By a hitherto undefined mechanism, the activity of gamma-secretase gives rise to Abeta peptides of different lengths, where Abeta42 is considered to play a particular role in AD. In this study we have examined the role of the large hydrophilic loop (amino acids 320-374, encoded by exon 10) of presenilin 1 (PS1), the catalytic subunit of gamma-secretase, for gamma-secretase complex formation and activity on Notch and APP processing. Deletion of exon 10 resulted in impaired PS1 endoproteolysis, gamma-secretase complex formation, and had a differential effect on Abeta-peptide production. Although the production of Abeta38, Abeta39, and Abeta40 was severely impaired, the effect on Abeta42 was affected to a lesser extent, implying that the production of the AD-related Abeta42 peptide is separate from the production of the Abeta38, Abeta39, and Abeta40 peptides. Interestingly, formation of the intracellular domains of both APP and Notch was intact, implying a differential cleavage activity between the epsilon/S3 and gamma sites. The most C-terminal amino acids of the hydrophilic loop were important for regulating APP processing. In summary, the large hydrophilic loop of PS1 appears to differentially regulate the relative production of different Abeta peptides without affecting Notch processing, two parameters of significance when considering gamma-secretase as a target for pharmaceutical intervention in AD.

The rapid development of the care makes it important to have relevant cost information for cost-effectiveness assessments. The aim of this study is to estimate the health care cost of a disseminated breast cancer relapse in Sweden. A retrospective cohort study of women with disseminated breast cancer in Sweden was done. The individual case records were reviewed and all data concerning treatments, hospitalisation, examinations and palliative care were collected. The study included 53 patients with a total mean cost of euro93,700 (95% Confidence Interval (CI): euro78,500-euro109,600). Drugs and hospitalisations were the largest single cost sources. HER2-positive patients had slightly higher mean costs (euro123,300), while triple negative patients had slightly lower mean costs (euro70,600). The current costs for patients with disseminated breast cancer are considerably higher than those previously shown, which may have important consequences for economic evaluations of interventions aimed at reducing the risk of disseminated breast cancer.

Background: Acute renal failure after contrast-induced nephropathy is a clinically important and costly complication after the use of iodine-based contrast media. We investigated the cost and cost-effectiveness of 2 contrast media in patients at high risk of contrast-induced nephropathy. Methods: The analyses were based on a randomized, prospective, multinational clinical study comparing the nephrotoxic effects of an isosmolar nonionic contrast medium, iodixanol, with those of a low-osmolar nonionic contrast medium, iohexol. Resource utilization data were obtained from the study and from a retrospective review of patients' hospital records. Swedish, German, and French unit prices were applied to resources used. Between-group differences in average costs were analyzed using a nonparametric bootstrap method. Results: Resource utilization data for 125 patients were analyzed. Seven contrast media-related serious adverse reactions, of which 6 were acute renal failures, were noted in 6 patients receiving iohexol. Two patients in the iodixanol group had 1 nonserious reaction each. The mean hospitalization cost per patient was €489, €573, and €393 lower after iodixanol than after iohexol using Swedish, German, and French unit prices, respectively. The mean per-patient costs of treating adverse drug reactions were €371, €399, and €445 lower after iodixanol than after iohexol, using the respective unit prices (P = 0.01). Iodixanol was cost-effective compared with iohexol, with both lower costs and better effects related to fewer adverse drug reactions. Conclusions: The isosmolar contrast medium iodixanol appears to be cost-effective when compared with a low-osmolar contrast medium, iohexol, in diabetic patients with renal impairment undergoing angiography. © 2005, Elsevier Inc. All rights reserved.

Objective. To analyse the variation between primary care centres (PCCs) with regard to prescribing antibiotics and to investigate whether the variation can be explained by factors related to patient satisfaction and to socio-demographic characteristics of the populations in the catchment areas of the PCCs. Methods. The frequency of prescription of antibiotics by GPs at the PCCs was used as the dependent variable in a multivariate regression analysis. Questionnaire data for patient satisfaction and register data for socio-demographic characteristics were used as explanatory variables. The study was set in a county in south-east Sweden, and 6734 patients consulting GPs at 39 out of the 41 PCCs in the county participated. Variables correlating with the frequency of antibiotics prescription at PCC level and with patient satisfaction were the main outcome measures. Results. A seven-fold variation in the extent of the prescription of antibiotics between the PCCs was observed. In the multivariate analysis, a high antibiotic prescription rate relates to high overall patient satisfaction with GP consultation as well as to the share of males in the listed population but to low satisfaction with the time spent by the GP on listening to the patient. Conclusion. A high frequency of prescription of antibiotics at a PCC may reflect a general disposition among GPs to give priority to maintaining good relations with the patients. However, a low level of prescription may be consistent with patient satisfaction if more time is spent on listening to and informing the patients. Thus more time spent on listening to the patients may reduce the prescription of antibiotics without reducing patient satisfaction.

The interleukin-1 (IL-1) receptor antagonist (IL-1ra) is an endogenous antagonist that blocks the effects of the proinflammatory cytokines IL-1alpha and IL-1beta by occupying the type I IL-1 receptor. Here we describe transgenic mice with astrocyte-directed overexpression of the human secreted IL-1ra (hsIL-1ra) under the control of the murine glial fibrillary acidic protein (GFAP) promoter. Two GFAP-hsIL-1ra strains have been generated and characterized further: GILRA2 and GILRA4. These strains show a brain-specific expression of the hsIL-1ra at the mRNA and protein levels. The hsIL-1ra protein was approximated to approximately 50 ng/brain in cytosolic fractions of whole brain homogenates, with no differences between male and female mice or between the two strains. Furthermore, the protein is secreted, inasmuch as the concentration of hsIL-1ra in the cerebrospinal fluid was 13 (GILRA2) to 28 (GILRA4) times higher in the transgenic mice than in the control animals. To characterize the transgenic phenotype, GILRA mice and nontransgenic controls were injected with recombinant human IL-1beta (central injection) or lipopolysaccharide (LPS, peripheral injection). The febrile response elicited by IL-1beta (50 ng/mouse icv) was abolished in hsIL-1ra-overexpressing animals, suggesting that the central IL-1 receptors were occupied by antagonist. The peripheral LPS injection (25 micrograms/kg ip) triggered a fever in overexpressing and control animals. Moreover, no differences were found in LPS-induced (100 and 1,000 micrograms/kg ip; 1 and 6 h after injection) IL-1beta and IL-6 serum levels between GILRA and wild-type mice. On the basis of these results, we suggest that binding of central IL-1 to central IL-1 receptors is not important in LPS-induced fever or LPS-induced IL-1beta and IL-6 plasma levels.

The occurrence of the endogenous receptor antagonist for the cytokine interleukin-1 in the rat adrenal gland was analyzed y polymerase chain reaction and by immunohistochemistry using a rabbit polyclonal antiserum. Expression of interleukin-1 receptor antagonist mRNA was demonstrated in both adrenal medulla and cortex, and a marked increase in the transcription was observed after systemic administration of lipopolysaccharides. Interleukin-1 receptor antagonist immunoreactivity was seen in the adrenal medulla, and the immunofluorescence intensity was stronger in the adrenergic, phenylethanolamine N-methyltransferase-positive cells than in the noradrenergic chromaffin cells. The distribution of interleukin-1 receptor antagonist protein is complementary to that of interleukin-1 alpha-like immunoreactivity found in phenylethanolamine N-methyltransferase-negative cells and overlaps with and resembles the distribution of interleukin-1 beta-immunoreactive material. The expression of the interleukin-1 receptor antagonist in the adrenal gland complements previous findings of large constitutive pools of interleukin-1 alpha and interleukin-1 beta in this neuroendocrine organ and also suggests participation of adrenal interleukin-1 receptor antagonist in neuroimmune modulation.