312 research outputs found

    Modeling the effect of flow-induced mechanical erosion during coffee filtration

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    The espresso extraction process involves a complex transport inside a geometry-changing porous medium. Large solid grains forming the majority of the porous medium can migrate, swell, and consolidate, and they can also morphologically change during flow, i.e., being mechanically eroded by hydrodynamic forces. These processes can, in turn, have a significant back-effect on the flow and the related coffee extraction profiles. In this article, we devise a bottom–up erosion model in the framework of smoothed dissipative particle dynamics to consider flow-induced morphological changes of the coffee grains. We assume that the coffee grains are not completely wetted and remain brittle. We found that heterogeneity in both the filtration direction and the transverse direction can be induced. The former is controlled by the angle of internal friction while the latter is controlled by both the cohesion parameter and the angle of internal friction. Not restricted to the modeling of espresso extraction, our model can also be applied to other eroding porous media. Our results suggest that, under ideal porous flow conditions, we can control the heterogeneity (in both the pressure drop direction and the transverse direction) of an eroding medium by tuning the yield characteristics of the eroding material

    Simultaneous quantification of antioxidants paraxanthine and caffeine in human saliva by electrochemical sensing for CYP1A2 phenotyping

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    The enzyme CYP1A2 is responsible for the metabolism of numerous antioxidants in the body, including caffeine, which is transformed into paraxanthine, its main primary metabolite. Both molecules are known for their antioxidant and pro-oxidant characteristics, and the paraxanthine-to-caffeine molar ratio is a widely accepted metric for CYP1A2 phenotyping, to optimize dose\u2013 response effects in individual patients. We developed a simple, cheap and fast electrochemical based method for the simultaneous quantification of paraxanthine and caffeine in human saliva, by differential pulse voltammetry, using an anodically pretreated glassy carbon electrode. Cyclic voltammetry experiments revealed for the first time that the oxidation of paraxanthine is diffusion controlled with an irreversible peak at ca. +1.24 V (vs. Ag/AgCl) in a 0.1 M H2 SO4 solution, and that the mechanism occurs via the transfer of two electrons and two protons. The simultaneous quantification of paraxanthine and caffeine was demonstrated in 0.1 M H2 SO4 and spiked human saliva samples. In the latter case, limits of detection of 2.89 \ub5M for paraxanthine and 5.80 \ub5M for caffeine were obtained, respectively. The sensor is reliable, providing a relative standard deviation within 7% (n = 6). Potential applicability of the sensing platform was demonstrated by running a small scale trial on five healthy volunteers, with simultaneous quantification by differential pulse voltammetry (DPV) of paraxanthine and caffeine in saliva samples collected at 1, 3 and 6 h postdose administration. The results were validated by ultra-high pressure liquid chromatography and shown to have a high correlation factor (r = 0.994)

    Estimation of cost-of-illness in patients with psoriasis in Switzerland

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    BACKGROUND: Evaluation of the current clinical treatment of psoriasis in Switzerland remains to be measured with the parameters cost-of-illness and quality of life. Objective: To obtain data on out-of-pocket expenses, costs of outpatient/office-based care and inpatient care for psoriasis, and to extrapolate total costs by state of severity to the entire Swiss population. METHODS: 1200 retrospective surveys were distributed to patient members of the Swiss Psoriasis and Vitiligo Society, and 400 surveys to office-/hospital-based Swiss dermatologists. The reference year for data collection was 2005. Patients were stratified into three subgroups according to severity of disease. Costs of inpatient care were measured by the amount of hospital days of psoriatic patients from the Swiss Federal Hospital Statistics. RESULTS: 383 patient questionnaires, and 170 cases documented by 57 dermatologists were analyzed. Out-of-pocket expenses/costs for ambulatory care per patient and year ranged from CHF 600-1100 for mild psoriasis to CHF 2400-9900 for severe psoriasis. Including costs for inpatient care of approximately CHF 60 million, the total annual costs for psoriasis in Switzerland in 2004/5 amounted to approximately CHF 314-458 million. CONCLUSIONS: Moderate-to-severe psoriasis is associated with a significant impact on the quality of life and at least 4-fold higher costs than mild psoriasis, indicating the need for efficient control of the disease. This cost-of-illness study provides specific health economic data for future healthcare decision making, particularly with the advent of new therapeutic agents for effective psoriasis control

    Estimation of cost-of-illness in patients with psoriasis in Switzerland

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    BACKGROUND: Evaluation of the current clinical treatment of psoriasis in Switzerland remains to be measured with the parameters cost-of-illness and quality of life. Objective: To obtain data on out-of-pocket expenses, costs of outpatient/office-based care and inpatient care for psoriasis, and to extrapolate total costs by state of severity to the entire Swiss population. METHODS: 1200 retrospective surveys were distributed to patient members of the Swiss Psoriasis and Vitiligo Society, and 400 surveys to office-/hospital-based Swiss dermatologists. The reference year for data collection was 2005. Patients were stratified into three subgroups according to severity of disease. Costs of inpatient care were measured by the amount of hospital days of psoriatic patients from the Swiss Federal Hospital Statistics. RESULTS: 383 patient questionnaires, and 170 cases documented by 57 dermatologists were analyzed. Out-of-pocket expenses/costs for ambulatory care per patient and year ranged from CHF 600-1100 for mild psoriasis to CHF 2400-9900 for severe psoriasis. Including costs for inpatient care of approximately CHF 60 million, the total annual costs for psoriasis in Switzerland in 2004/5 amounted to approximately CHF 314-458 million. CONCLUSIONS: Moderate-to-severe psoriasis is associated with a significant impact on the quality of life and at least 4-fold higher costs than mild psoriasis, indicating the need for efficient control of the disease. This cost-of-illness study provides specific health economic data for future healthcare decision making, particularly with the advent of new therapeutic agents for effective psoriasis control

    Arsenic trioxide down-regulates antiapoptotic genes and induces cell death in mycosis fungoides tumors in a mouse model

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    Background: Mycosis fungoides (MF) is the most frequent cutaneous T-cell lymphoma (CTCL). Arsenic trioxide (As2O3) has recently been shown to be effective against leukemias, so we studied whether As2O3 induces apoptosis of CTCL cells in vitro. We further investigated if As2O3 is effective in a MF mouse model. Material and methods: Annexin V/7-amino-actinomycin-D stainings were carried out to investigate if As2O3 induced apoptosis of CTCL cell lines. To study the underlying mechanisms, the effects of As2O3 on various transcription factors and apoptosis regulating proteins were analyzed by western blots, electrophoretic mobility shift assays and transcription factor enzyme-linked immunosorbent assays. The ability of As2O3 to induce tumor regression was investigated in a MF mouse model. Results: As2O3-induced apoptosis was paralleled by a reduction of the DNA-binding activities of transcription factors of the NFkB and signal transducer and activator of transcription gene families and reduced expression of the antiapoptotic proteins bcl-1, bcl-xL and mcl-1. Local injections of 200 μM As2O3 into tumors caused complete remissions in five of six mice and one partial remission. Conclusions: As2O3 induced apoptosis of CTCL cells by the down-regulation of transcription factors that stimulate the expression of antiapoptotic genes. Local injection of As2O3 into MF tumor-bearing mice resulted in tumor regressio

    The limits of inter-religious dialogue and the form of football rituals: The case of Bosnia-Herzegovina

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    The difficulties with interfaith dialogue are linked, at least in part, to the lack of ritual forms (consisting of rules, ceremonial idioms, liturgy, and repertoires of action) designed to unite and integrate the "meta-group "formed by the various religious communities. By means of ethnographic research conducted in Bosnia-Herzegovina, the author studied the mechanisms with which, under particular conditions, some forms of collective ritual were able to create opportunities for the re-integration of the Bosnian population, which had been profoundly divided after the terrible war of 199295. Comparing the forms of religious rituals and those of sports ritualsin particular, of football ritualsthe author develops some considerations that can be applied to the general debate about inter-religious dialogue. The comparison brings to light some of the limits and difficulties that religious institutions encounter in giving life to an interfaith dialogue that directly and concretely involves the members of different communities. © 2007 Social Compass

    Tofacitinib May Inhibit Myofibroblast Differentiation from Rheumatoid-Fibroblast-like Synoviocytes Induced by TGF-β and IL-6

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    During rheumatoid arthritis (RA), the pathogenic role of resident cells within the synovial membrane is suggested, especially for a population frequently referred to as fibroblast-like synoviocytes (FLSs). In this study, we assess the markers of myofibroblast differentiation of RA-FLSs by ex vivo observations and in vitro evaluations following the stimulation with both TGF-β and IL-6. Furthermore, we investigated the possible inhibiting role of tofacitinib, a JAK inhibitor, in this context. Myofibroblast differentiation markers were evaluated on RA synovial tissues by immune-fluorescence or immune-histochemistry. RA-FLSs, stimulated with transforming growth factor (TGF-β) and interleukin-6 (IL-6) with/without tofacitinib, were assessed for myofibroblast differentiation markers expression by qRT-PCR and Western blot. The same markers were evaluated following JAK-1 silencing by siRNA assay. The presence of myofibroblast differentiation markers in RA synovial tissue was significantly higher than healthy controls. Ex vivo, α-SMA was increased, whereas E-Cadherin decreased. In vitro, TGF-β and IL-6 stimulation of RA-FLSs promoted a significant increased mRNA expression of collagen I and α-SMA, whereas E-Cadherin mRNA expression was decreased. In the same conditions, the stimulation with tofacitinib significantly reduced the mRNA expression of collagen I and α-SMA, even if the Western blot did not confirm this finding. JAK-1 gene silencing did not fully prevent the effects of stimulation with TGF-β and IL-6 on these features. TGF-β and IL-6 stimulation may play a role in mediating myofibroblast differentiation from RA-FLSs, promoting collagen I and α-SMA while decreasing E-Cadherin. Following the same stimulation, tofacitinib reduced the increases of both collagen I and α-SMA on RA-FLSs, although further studies are needed to fully evaluate this issue and confirm our results
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