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The aim of the current research project was to explore the possibilities of combining pressurized carbon dioxide with hot stage extrusion during manufacturing of solid dispersions of itraconazole and polyvinylpyrrolidone-co-vinyl acetate 64 (PVP-VA 64) and to evaluate the ability of the pressurized gas to act as a temporary plasticizer as well as to produce a foamed extrudate. Pressurized carbon dioxide was injected into a Leistritz Micro 18 intermeshing co-rotating twin-screw melt extruder using an ISCO 260D syringe pump. The physicochemical characteristics of the extrudates with and without injection of carbon dioxide were evaluated with reference to the morphology of the solid dispersion and dissolution behaviour and particle properties. Carbon dioxide acted as plasticizer for itraconazole/PVP-VA 64, reducing the processing temperature during the hot stage extrusion process. Amorphous dispersions were obtained and the solid dispersion was not influenced by the carbon dioxide. Release of itraconazole from the solid dispersion could be controlled as a function of processing temperature and pressure. The macroscopic morphology changed to a foam-like structure due to expansion of the carbon dioxide at the extrusion die. This resulted in increased specific surface area, porosity, hygroscopicity and improved milling efficiency.  相似文献   
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Usher syndrome type II (USH2) is characterised by moderate to severe high-frequency hearing impairment, progressive visual loss due to retinitis pigmentosa and intact vestibular responses. Three loci are known for USH2, however, only the gene for USH2a (USH2A) has been identified. Mutation analysis of USH2A was performed in 70 Dutch USH2 families. Ten mutations in USH2A were detected, of which three are novel, c.949C>A, c.2242C>T (p.Gln748X) and c.4405C>T (p.Gln1468X). Including 9 previously published Dutch USH2a families, estimates of the prevalence of USH2a in the Dutch USH2 population were made. Mutations were identified in 62% of the families. In 28% both mutated alleles were identified, whereas in 34% the mutation in only one allele was found. It is estimated that about 28% of the Dutch USH2 families have a different causative gene. Analysis of deduced haplotypes suggests that c.1256G>T (p.Cys419Phe) is a Dutch ancestral mutation, occurring in 16% of the alleles.  相似文献   
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Hepatic stellate cell (HSC) activation is a key event in the natural process of wound healing as well as in fibrosis development in liver. Current in vitro models for HSC activation contribute significantly to the understanding of HSC biology and fibrogenesis but still fall far short of recapitulating in vivo intercellular functional and anatomic relationships. In addition, when cultured on uncoated plastic, HSC spontaneously activate, which makes HSC activation difficult to regulate or analyze. We have examined whether the use of precision-cut liver slices might overcome these limitations. Liver slices (8 mm diameter, 250 microm thickness) were generated from normal rat liver and incubated for 3 or 16 h with increasing doses of carbon tetrachloride (CCl4). Rat liver slices remained viable during incubation, as shown by minimal enzyme leakage. Expression of markers for HSC activation and the onset of fibrogenesis in the liver slices was studied using real-time PCR and Western blotting. In unstimulated liver slices, mRNA and protein levels of desmin, heat shock protein 47, and alpha B-crystallin remained constant, indicating quiescence of HSC, whereas Krüppel-like factor 6 expression was increased. In contrast, incubation with CCl4 led to a time- and dose-dependent increase in mRNA expression of all markers and an increased alpha B-crystallin protein expression. In conclusion, we have developed a technique to induce activation of quiescent HSC in rat liver slices. This model permits the study of toxicity-induced HSC activation within a physiological milieu, not only in animal but ultimately also in human tissue, and could contribute to the reduction of animal experiments.  相似文献   
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The aim of this study was to evaluate the effect of selective feticide (SF) compared to expectant management (EM) on perinatal outcome in dichorionic and monochorionic twins discordant for anencephaly. For this purpose, we conducted a systematic review of literature and added ten unpublished cases. As a result, we found that in dichorionic twins, mean gestational age (GA) at birth in the SF group was 38.0 weeks versus 34.9 weeks (P = 0.0002). Mean birth weight was 2922 g in the SF group versus 2474 g (P = 0.03). In monochorionic twins, mean GA at birth was 35.2 weeks versus 32.7 weeks (P = 0.1). Mean birth weight was 2711 g versus 1667 g (P = 0.0001).We conclude that while SF does not reduce perinatal mortality, it does result in significantly longer gestations and higher birth weight, and appears to be the management of choice in dichorionic twins discordant for anencephaly. In monochorionic twins, SF also increases birth weight, but in view of the complexity of this group, no clear recommendations can be made.  相似文献   
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OBJECTIVES: To analyse the effect of a dose increase in patients with severe rheumatoid arthritis (RA) with insufficient clinical response to 3 mg/kg infliximab every 8 weeks. METHODS: Patients suffering from active refractory RA despite methotrexate, were treated with i.v. infusions of infliximab (3 mg/kg) on week 0, 2, 6 and every 8 weeks thereafter. Based on the clinical judgement at week 22, patients received a dose increase of 100 mg from week 30 on. The American College of Rheumatology (ACR) core set for disease activity measures was regularly assessed. RESULTS: Five hundred and eleven RA patients were included. At week 22, 61.4, 34 and 14.1% of all patients met ACR 20, ACR 50 and ACR 70 criteria, respectively, and 6.1% of patients were in remission. A low swollen joint count at baseline was correlated with improvement at week 22 for ACR 20 (P < 0.06), ACR 50 (P < 0.06) and ACR 70 (P < 0.005). The change in HAQ score between weeks 0 and 22 was predictive for response at week 54 (P < 0.01). The dose of infliximab was increased by 100 mg in 22% of the patients. Most baseline values of patients requiring dose increase were higher (P < or = 0.001) than the baseline values of the remaining patients. Increasing the dose of infliximab by one vial from week 30 on could circumvent the partial loss of response in these patients. CONCLUSION: Infliximab use in this large out-patient cohort resulted in a significant clinical improvement. A subgroup that partially lost response during the first 22 weeks could regain response by adding 100 mg of infliximab to the subsequent doses. Due to the current study design, however, a regression to the mean like effect could not be ruled out.  相似文献   
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Objective

Participation in society of persons with chronic diseases receives increasing attention. However, little is known about which components of participation are most relevant to life satisfaction. This study examines the association between several aspects of social role participation and satisfaction with life (SWL) in patients with ankylosing spondylitis (AS) compared to population controls.

Methods

In a cross‐sectional study, participants completed the Social Role Participation Questionnaire (SRPQ) and SWL scale. The SRPQ assesses several dimensions of participation (importance, satisfaction with performance, and satisfaction with time and physical difficulty) in 11 roles representing 3 domains (interpersonal relations, leisure, and work). For individuals with AS and controls, the association between role domains and SWL was examined using linear regression for each participation dimension separately, in the total and the employed population, adjusting for age, sex, education, and income.

Results

A total of 246 AS patients (mean ± SD age 51 ± 12 years, 62% males, mean ± SD disease duration 17 ± 12 years) and 510 controls (mean ± SD age 42 ± 15 years, 70% males) were included. AS patients were more frequently (extremely) dissatisfied with life (17.9% versus 8.6%; P < 0.05). In the total and the employed population, less physical difficulty and higher satisfaction with interpersonal relations and leisure were associated with higher SWL, and this was somewhat stronger in patients than in controls (P < 0.1). In employed controls, but not in employed patients, satisfaction with work was independently associated with SWL.

Conclusion

These findings highlight the importance of supporting persons with AS in ameliorating social role participation, particularly in areas like close relationships and leisure activities, which are typically ignored when treating AS.
  相似文献   
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