736 research outputs found

    Measurement of adsorption of a single component from the liquid phase : modelling investigation and sensitivity analysis

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    In this work, we consider an alternative approach for the measurement of adsorption from the liquid phase. Consider a mixture consisting of a non-adsorbed component (B) and an adsorbed component (A) present at some low concentration. Initially, a feed of component B only flows through a column packed with an adsorbent. Then, the feed is switched to the mixture of A and B. As soon as the mixture enters the column, there will be a reduction in the outlet flow rate as component A leaves the liquid phase and passes into the adsorbed phase. There are three stages to this work. The first is to develop overall and component balances to show how the amount adsorbed of component A can be determined from the variation in the column outlet flow rate. The second is to determine the actual variation in the column outlet flow rate for both plug flow and axial-dispersed plug flow. The final stage is to consider the suitability of a gravity-fed system to deliver the feed to the column. An analysis of the results shows that the experimental arrangement should be able to accurately monitor adsorption from the liquid phase where the mass fraction of the solute is of the order of 1%: the limiting experimental factor is how constant the volumetric flow rate of the liquid feed can be maintained

    Quantitative analysis of videokymography in normal and pathological vocal folds: a preliminari study.

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    Videokymography (VKG) captures high-speed images of the vocal folds independently of the periodicity of the acoustic signal. The aim of this study was to preliminarily assess a software package that can objectively measure specific parameters of vocal fold vibration. From August 2009 until December 2010, we prospectively evaluated 40 subjects (Group A, 18 normal subjects; Group B, 14 patients with benign lesions of the middle third of the vocal fold, such as polyps and cysts; Group C, 8 patients treated by endoscopic excision of vocal fold benign lesions) by videoendoscopy, videolaryngostroboscopy, and VKG. A VKG camera was coupled to a 70 telescope and video was recorded during phonation. Images were objectively analyzed by a post-processing software tool (VKG-Analyser) with a user-friendly interface developed by our group. Different parameters were considered, including the ratio between the amplitude of the vibration of one vocal fold with respect to the contralateral (Ramp), the ratio between the period of one vocal fold vibration and the opposite one (Rper), and the ratio between the duration of the open and closed phase within a glottal cycle (Roc). Mean values for Ramp, Rper, and Roc in Group A were 1.05, 1.04, and 1.35, respectively; in Group B were 1.63, 0.92, and 0.97, respectively; and in Group C were 1.13, 0.91, and 1.85, respectively. Quantitative analysis of videokymograms by the herein presented tool, named VKG-Analyser, is useful for objective evaluation of the vibratory pattern in normal and pathologic vocal folds. Important future developments of this tool for the study of both physiologic and pathologic patterns of vocal fold vibration can be expected

    Behaviour and Degenerative Changes in the Basal Forebrain Systems of Aged Rats (12 Months Old) after Levo-Acetyl-Carnitine Treatments

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    One group of six male control rats [12 months old] and one group of six male rats of the same age, singularly maintained in a cage, and treated with acetyl-L-carnitine-HCl [(gamma-trimethyl-beta-acetyl-butyrobetaine-HCl: Sigma-Tau code ST200 or ALCAR: 60 mg/kg/day[7]/po)] for six months were tested in the spatial learning/memory Morris mazewater task and for atrophy and cell loss in seven myelo- and cytostructurally defined basal forebrain (BF) cholinergic regions [Freddi et al., 2009]. Coronal sections 25 ?m thick were cut through the BF regions and processed every 200 ?m for choline acetyltransferase (ChAT) immunohistochemistry. The ALCAR-treated rats had significantly shorter exit times on the Morris maze-water task test than the control rats (average \ub1 SD 28.3 \ub1 12.4 s vs. 61.16 \ub1 4.67 s; t = 6.07, DOF = 10, P = 0.0001). Degenerative morphological changes in the BF ChAT-positive cells were observed in the substantia innominata pars anterior of the control rats but not in the treated animals (P < 0.05). In the BF, the counted and estimated average number of ChAT + cells in the 12-month-old ALCAR-treated rats (ChAT-ALCAR-12+ [Nos. 2,3,4]) was higher but not significantly (15.288 \ub1 3281) than that counted and estimated in the 12-month-old control rats [(ChAT-CT-12 [Nos. 1,2,3]) (11.508 \ub1 3868), t = 1.82, DOF = 10, P = 0.319]. In the substantia innominata pars posterior, the ChAT+ cells were significantly more numerous (P < 0.05) in the 12-month-old ALCAR-treated rats (ChAT-ALCAR-12 + [Nos. 2,3,4]) than in the control rats (ChAT-CT-12 [Nos. 1,2,3]). Above all, these results dem-onstrate that treatment with ALCAR from the age of 6 up to 12 months significantly attenuated spatial learning/memory impairment on the Morris maze-water behavioral task (P < 0.001) and also importantly reduced degeneration in size and number of cholinergic cells in the nucleus basalis magnocellularis of the BF. Accordingly, the surviving cholinergic neurons found in the BF of the ALCAR-treated rats might play an important role in modulating cortical activity and facilitating processes of attention, learning and memory

    Gemcitabine plus vinorelbine in elderly or unfit patients with non-small cell lung cancer

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    Cisplatin-based combinations are efficacious in increasing the overall survival of patients with non-small cell lung cancer (NSCLC), but their toxicity makes them unsuitable for elderly and unfit patients. The primary objective of this non-randomized phase II study was to evaluate the feasibility and activity of the gemcitabine plus vinorelbine combination in previously untreated elderly and/or unfit patients with measurable stage III or IV NSCLC. Forty-three patients aged ≄ 65 years or with contraindications against cisplatin treatment (36 males and seven females: median age 66 years; range 48–75: PS 0 = 11, PS 1 = 19, PS 2 = 13) received intravenous (i.v.) gemcitabine 1000 mg m–2, followed by vinorelbine 25 mg m–2i.v. on day 1 and 8 every 21 days. Fifteen patients (34.9%) achieved partial remission (confidence interval: 27.6–42.2%) for a median duration of 6 months; the median survival of these patients has not yet been reached. A further 15 had stable disease for a median of 4 months and a median survival of 7 months. The 10 patients (23.2%) who experienced disease progression had a median survival of 4 months. Three patients are not evaluable. The 1-year actuarial survival rate is 31.1%. The treatment was well tolerated: only 35% of the patients had grade 3 or 4 granulocytopenia on day 14, none experienced episodes of neutropenic fever, and there was no evidence of severe haematological toxicity upon recycling. Only 9% of the patients suffered from gastrointestinal toxicity (grade 3); increased but reversible transaminase levels were observed in 11.6%. In conclusion, the results of this phase II study show that the combination of gemcitabine and vinorelbine is active and well tolerated in NSCLC, and thus encourage its use in elderly or unfit patients. © 2000 Cancer Research Campaig

    Transplantation of Skeletal Muscle-Derived Sca-1âș/PW1âș/Pax7⁻ Interstitial Cells (PICs) Improves Cardiac Function and Attenuates Remodeling in Mice Subjected to Myocardial Infarction

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    We have previously shown that skeletal muscle-derived Sca-1âș/PW1âș/Pax7⁻ interstitial cells (PICs) are multi-potent and enhance endogenous repair and regeneration. Here, we investigated the regenerative potential of PICs following intramyocardial transplantation in mice subjected to an acute myocardial infarction (MI). MI was induced through the ligation of the left anterior descending coronary artery in 8-week old male C57BL/6 mice. 5 × 10⁔ eGFP-labelled PICs (MI + PICs; n = 7) or PBS (MI-PBS; n = 7) were injected intramyocardially into the border zone. Sham mice (n = 8) were not subjected to MI, or the transplantation of PICs or PBS. BrdU was administered via osmotic mini-pump for 14 days. Echocardiography was performed prior to surgery (baseline), and 1-, 3- and 6-weeks post-MI and PICs transplantation. Mice were sacrificed at 6 weeks post-MI + PICs transplantation, and heart sections were analysed for fibrosis, hypertrophy, engraftment, proliferation, and differentiation of PICs. A significant (\u1d631 < 0.05) improvement in ejection fraction (EF) and fractional shortening was observed in the MI-PICs group, compared to MI + PBS group at 6-weeks post MI + PICs transplantation. Infarct size/fibrosis of the left ventricle significantly (\u1d631 < 0.05) decreased in the MI-PICs group (14.0 ± 2.5%), compared to the MI-PBS group (32.8 ± 2.2%). Cardiomyocyte hypertrophy in the border zone significantly (\u1d631 < 0.05) decreased in the MI-PICs group compared to the MI-PBS group (330.0 ± 28.5 ”M2 vs. 543.5 ± 26.6 ”m2), as did cardiomyocyte apoptosis (0.6 ± 0.9% MI-PICs vs. 2.8 ± 0.8% MI-PBS). The number of BrdU+ cardiomyocytes was significantly (\u1d631 < 0.05) increased in the infarct/border zone of the MI-PICs group (7.0 ± 3.3%), compared to the MI-PBS group (1.7 ± 0.5%). The proliferation index (total BrdU+ cells) was significantly increased in the MI-PICs group compared to the MI-PBS group (27.0 ± 3.4% vs. 7.6 ± 1.0%). PICs expressed and secreted pro-survival and reparative growth factors, supporting a paracrine effect of PICs during recovery/remodeling. Skeletal muscle-derived PICs show significant reparative potential, attenuating cardiac remodelling following transplantation into the infarcted myocardium. PICs can be easily sourced from skeletal muscle and therefore show promise as a potential cell candidate for supporting the reparative and regenerative effects of cell therapie
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