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Vitro Results (vitro + result)
Selected AbstractsThe combination of epigallocatechin gallate and curcumin suppresses ER,-breast cancer cell growth in vitro and in vivoINTERNATIONAL JOURNAL OF CANCER, Issue 9 2008Tiffany J. Somers-Edgar Abstract Both epigallocatechin gallate (EGCG) and curcumin have shown efficacy in various in vivo and in vitro models of cancer. This study was designed to determine the efficacy of these naturally derived polyphenolic compounds in vitro and in vivo, when given in combination. Studies in MDA-MB-231 cells demonstrated that EGCG + curcumin was synergistically cytotoxic and that this correlated with G2/M-phase cell cycle arrest. After 12 hr, EGCG (25 ,M) + curcumin (3 ,M) increased the proportion of cells in G2/M-phase to 263 ± 16% of control and this correlated with a 50 ± 4% decrease in cell number compared to control. To determine if this in vitro result would translate in vivo, athymic nude female mice were implanted with MDA-MB-231 cells and treated with curcumin (200 mg/kg/day, po), EGCG (25 mg/kg/day, ip), EGCG + curcumin, or vehicle control (5 ml/kg/day, po) for 10 weeks. Tumor volume in the EGCG + curcumin treated mice decreased 49% compared to vehicle control mice (p < 0.05), which correlated with a 78 ± 6% decrease in levels of VEGFR-1 protein expression in the tumors. Curcumin treatment significantly decreased tumor protein levels of EGFR and Akt, however the expression of these proteins was not further decreased following combination treatment. Therefore, these results demonstrate that the combination of EGCG and curcumin is efficacious in both in vitro and in vivo models of ER,- breast cancer and that regulation of VEGFR-1 may play a key role in this effect. © 2007 Wiley-Liss, Inc. [source] Fluoride down-regulates the expression of matrix metalloproteinase-20 in human fetal tooth ameloblast-lineage cells in vitroEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2006Yan Zhang Fluoride is associated with a decrease in the incidence of dental caries, but excessive fluoride intake during tooth enamel formation can result in enamel fluorosis. Fluorosed enamel has increased porosity, which has been related to a delay in the removal of amelogenin proteins as the enamel matures. This delay in protein removal suggests that fluoride may affect either the amount or the activity of enamel matrix proteinases. In this study, we investigated the role of fluoride in the synthesis and secretion of matrix metalloproteinase-20 (MMP-20), the proteinase primarily responsible for the initial hydrolysis of amelogenin during the secretory stage of enamel formation. Cultured human fetus tooth organ ameloblast-lineage cells were exposed to 10 µM fluoride and analyzed for synthesis of MMP-20. Immunoblotting showed that 10 µM NaF down-regulated the synthesis of MMP-20 by 21% compared with control cells, but did not alter the amount of amelogenin or kalikrein-4 (KLK-4) synthesized by the cells. Real-time polymerase chain reaction (PCR) showed that 10 µM NaF down-regulated MMP-20 mRNA expression to 28% of the levels found in the non-treated cells. These in vitro results suggest that fluoride can alter the expression of MMP-20 by ameloblasts, resulting in a disturbance of the balance between MMP-20 and its substrate that may contribute to the retention of amelogenins in the formation of fluorosed enamel. [source] A Hibiscus Abelmoschus seed extract as a protective active ingredient to favour FGF-2 activity in skinINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 6 2009D. Rival Synopsis In the skin, heparin, heparan sulphate and heparan sulphate proteoglycans control the storage and release of growth factors and protect them from early degradation. We developed a cosmetic active ingredient containing Hibiscus Abelmoschus seed extract (trade name LinefactorÔ) that can maintain the FGF-2 content in the skin by mimicking the protective effect of heparan sulphate proteoglycans. By preventing the natural degradation of FGF-2, Hibiscus Abelmoschus seed extract maintains the bioavailability of this growth factor for its target cells, i.e. skin fibroblasts. Our in vitro evaluations showed that this ingredient exhibited heparan sulphate-like properties and dose-dependently protected FGF-2 from thermal degradation. We could also show that, in turn, the protected FGF-2 could stimulate the synthesis of sulphated GAGs, the natural protective molecules for FGF-2, thus providing a double protection. Finally, the in vitro results were confirmed in vivo thanks to a clinical study in which skin biomechanical properties and reduction in wrinkles were assessed. Résumé Dans la peau, l'héparane sulfate et les protéoglycanes à héparane sulfate contrôlent le stockage et la libération des facteurs de croissance et les protègent de la dégradation prématurée. Nous avons développé un actif cosmétique contenant un extrait de graines d'Hibiscus Abelmoschus capable de maintenir le contenu en FGF-2 de la peau en mimant l'effet protecteur des protéoglycanes à héparane sulfate. En prévenant la dégradation naturelle du FGF-2, l'extrait de graines d'Hibiscus Abelmoschus maintient la biodisponibilité de ce facteur de croissance pour ses cellules cibles que sont les fibroblastes de la peau. Les évaluations in vitro ont montré que cet ingrédient possédait des propriétés « héparane sulfate-like » et protégeait le FGF-2 de la dégradation thermique de façon dose-dépendante. Nous avons également pu montrer qu'en retour, le FGF-2 protégé pouvait stimuler la synthèse de GAGs sulfatés naturellement protecteurs du FGF-2, offrant ainsi une double protection. Enfin, les résultats in vitro ont été confirmés in vivo par une étude clinique au cours de laquelle les propriétés biomécaniques de la peau ainsi que la réduction des rides ont étéévaluées. [source] Effect of cyclosporin A in Lewis rats in vivo and HeLa cells in vitroJOURNAL OF APPLIED TOXICOLOGY, Issue 3 2002Andrea Sovcikova Abstract The aim of this study was to compare the effect of cyclosporin A (CsA) in inbred Lewis rats with published assessment of immunotoxicity in ,classical' outbred Wistar rats. A second purpose was to consider the contribution of a panel of in vitro assays in cell cultures when added to an immunotoxicity study in vivo. The in vivo effect of CsA was investigated in a 28-day subacute immunotoxicity study in male Lewis rats at three different concentrations: 1.25, 5 and 20 mg kg,1. The highest dose of CsA exceeded the maximum tolerated dose. A drop in body, spleen and popliteal lymph node weight of exposed animals displayed symptoms of toxicity. At a high toxic dose, haematological changes showed a decrease in the leucocyte count and in the percentage of lymphocytes, and an increase in the percentage of polymorphonuclear leucocytes. The haematocrit was significantly dose-dependently suppressed in all rats exposed to CsA. A similar dose-dependent depression of the mean cell volume of erythrocytes was found in rats given high and middle doses of CsA. The phagocytic activity of polymorphonuclear leucocytes and monocytes also was significantly dose-dependently suppressed. No significant changes in primary antibody response to sheep erythrocytes or in vitro proliferative response of spleen lymphocytes to mitogens were found in those rats. A battery of in vitro cytotoxicity methods was selected for the evaluation of metabolic and functional activity of subcellular organelles (mitochondria, lysosomes) and for the detection of drug-induced superoxide-mediated damage in HeLa cells. This cell line was chosen because it has a lower activity of superoxide dismutase (SOD) than normal cells and is sufficiently sensitive for the detection of the induction of oxygen radicals. The in vitro results indicated a direct relationship between CsA cytotoxicity and a change in the mitochondrial enzyme activity, as well as an induction of superoxide production. The results of the study indicated that a combination of selected in vivo and in vitro methods is an inexpensive way to obtain more complex information on cell status affected by xenobiotics. Copyright © 2002 John Wiley & Sons, Ltd. [source] Metabolic changes detected by proton magnetic resonance spectroscopy in vivo and in vitro in a murin model of Parkinson's disease, the MPTP-intoxicated mouseJOURNAL OF NEUROCHEMISTRY, Issue 3 2008Carine Chassain Abstract Parkinson's disease is a neurodegenerative disorder characterized by the progressive loss of the dopaminergic neurons in the substantia nigra pars compacta, which project to the striatum. The aim of this study was to analyze in vivo and in vitro consequences of dopamine depletion on amount of metabolites in a mouse model of Parkinson's disease using proton 1H magnetic resonance spectroscopy (MRS). The study was performed on control mice (n = 7) and MPTP-intoxicated mice (n = 7). All the experiments were performed at 9.4 T. For in vivo MRS acquisitions, mice were anesthetized and carefully placed on an animal handling system with the head centered in birdcage coil used for both excitation and signal reception. Spectra were acquired in a voxel (8 ,L) centered in the striatum, applying a point-resolved spectroscopy sequence (TR = 4000 ms, TE = 8.8 ms). After in vivo MRS acquisitions, mice were killed; successful lesion verified by tyrosine hydroxylase immunolabeling on the substantia nigra pars compacta and in vitro MRS acquisitions performed on perchloric extracts of anterior part of mice brains. In vitro spectra were acquired using a standard one-pulse experiment. The absolute concentrations of metabolites were determined using jmrui (Lyon, France) from 1H spectra obtained in vivo on striatum and in vitro on perchloric extracts. Glutamate (Glu), glutamine (Gln), and GABA concentrations obtained in vivo were significantly increased in striatum of MPTP-lesioned mice (Glu: 15.5 ± 2.5 vs. 12.9 ± 1.0 mmol/L, p < 0.05; Gln: 2.3 ± 0.9 vs. 1.8 ± 0.6 mmol/L, p < 0.05; GABA: 2.3 ± 0.9 vs. 1.3 ± 0.6 mmol/L, p < 0.05). The in vitro results confirmed these results, Glu (10.9 ± 2.5 vs. 7.9 ± 1.7 ,mol/g, p < 0.05), Gln (6.8 ± 2.9 vs. 4.3 ± 1.0 ,mol/g, p < 0.05), and GABA (2.9 ± 0.9 vs. 1.5 ± 0.4 ,mol/g, p < 0.01). The present study strongly supports a hyperactivity of the glutamatergic cortico-striatal pathway hypothesis after dopaminergic denervation in association with an increase of striatal GABA levels. It further shows an increased of striatal Gln concentrations, perhaps as a strategy to protect neurons from Glu excitotoxic injury after striatal dopamine depletion. [source] Dopamine activates Nrf2-regulated neuroprotective pathways in astrocytes and meningeal cellsJOURNAL OF NEUROCHEMISTRY, Issue 1 2007Andy Y. Shih Abstract The transcription factor Nrf2 controls inducible expression of multiple antioxidant/detoxification genes. We previously found that Nrf2 -/- mice have increased sensitivity to in vivo mitochondrial stress and ischemia. Although Nrf2 regulated these forms of neuronal toxicity, it was unclear which injury-triggered signal(s) led to Nrf2 activation in vivo. In this study, we use primary cultures to test the hypothesis that excessive dopamine release can act as an endogenous Nrf2-inducing signal. We cultured two cell types that show increased Nrf2 activity during ischemia in vivo, astrocytes and meningeal cells. Cultures were infected with an adenovirus reporter of Nrf2 transcriptional activity. Dopamine-induced Nrf2 activity in both cell types by generating oxidative stressors, H2O2 and dopamine-quinones. Nrf2 activation in meningeal cells was significantly higher than astrocytes. The effect of dopamine was blocked by antioxidants, and by over-expression of either dominant-negative Nrf2 or Keap1. Nrf2 induction was specific to oxidative stress caused by catecholaminergic neurotransmitters as epinephrine also induced Nrf2, but the monoamine serotonin had no significant effect. These in vitro results suggest Nrf2 activity in astrocytes and meningeal cells link the neurotoxic actions of dopamine to neuroprotective pathways that may potentially modulate ischemic injury and neurodegeneration. [source] The natural compound n -butylidenephthalide derived from Angelica sinensis inhibits malignant brain tumor growth in vitro and in vivo3JOURNAL OF NEUROCHEMISTRY, Issue 4 2006Nu-Man Tsai Abstract The naturally-occurring compound, n -butylidenephthalide (BP), which is isolated from the chloroform extract of Angelica sinensis (AS-C), has been investigated with respect to the treatment of angina. In this study, we have examined the anti-tumor effects of n -butylidenephthalide on glioblastoma multiforme (GBM) brain tumors both in vitro and in vivo. In vitro, GBM cells were treated with BP, and the effects of proliferation, cell cycle and apoptosis were determined. In vivo, DBTRG-05MG, the human GBM tumor, and RG2, the rat GBM tumor, were injected subcutaneously or intracerebrally with BP. The effects on tumor growth were determined by tumor volumes, magnetic resonance imaging and survival rate. Here, we report on the potency of BP in suppressing growth of malignant brain tumor cells without simultaneous fibroblast cytotocixity. BP up-regulated the expression of Cyclin Kinase Inhibitor (CKI), including p21 and p27, to decrease phosphorylation of Rb proteins, and down-regulated the cell-cycle regulators, resulting in cell arrest at the G0/G1 phase for DBTRG-05MG and RG2 cells, respectively. The apoptosis-associated proteins were dramatically increased and activated by BP in DBTRG-05MG cells and RG2 cells, but RG2 cells did not express p53 protein. In vitro results showed that BP triggered both p53-dependent and independent pathways for apoptosis. In vivo, BP not only suppressed growth of subcutaneous rat and human brain tumors but also, reduced the volume of GBM tumors in situ, significantly prolonging survival rate. These in vitro and in vivo anti-cancer effects indicate that BP could serve as a new anti-brain tumor drug. [source] Adenosine A2a receptor-mediated inhibition of rod opsin mRNA expression in tiger salamanderJOURNAL OF NEUROCHEMISTRY, Issue 3 2002Peter D. Alfinito Abstract The neuromodulator adenosine mediates dark-adaptive changes in retinal photoreceptors through A2a receptors. In cold-blooded vertebrates, opsin mRNA expression is lower at night than during the day. In the present study, we tested whether adenosine could inhibit opsin mRNA expression in cultured rod cells and if endogenous adenosine acts to suppress opsin mRNA in the intact retina at night. Semi-quantitative in situ hybridization showed that treatment with 100 nm of the A2a/A2b agonist N,6 -[2-(3,5-dimethoxyphenyl)-2-(2-methylphenyl)-ethyl]adenosine (DPMA) reduced opsin mRNA 41% in cultured rod cells. The effect of DPMA was blocked by 10 µm of the A2a antagonist 8-(3-chlorostyryl)caffeine (CSC) but not by 10 µm of the A2b antagonist alloxazine. One micromolar adenosine alone had no effect on opsin mRNA. However, in the presence of the adenosine deaminase inhibitor erythro -9-(2-hydroxy-3-nonyl)adenine hydrochloride (EHNA), 1 µm adenosine reduced opsin mRNA 61%. EHNA alone reduced opsin mRNA by 26%. Consistent with an A2a receptor mechanism, 100 nm forskolin (adenylate cyclase agonist) decreased opsin mRNA 34%. Finally, northern blots showed that intravitreal injection of 10 µm CSC at night increased opsin I mRNA 38%. Thus, endogenous adenosine suppresses rod opsin I mRNA expression at night; in vitro results indicate this reduction occurs through A2a -like receptor binding and stimulation of adenylate cyclase activity. [source] Induction of apoptosis in the LNCaP human prostate carcinoma cell line and prostate adenocarcinomas of SV40T antigen transgenic rats by the Bowman,Birk inhibitorPATHOLOGY INTERNATIONAL, Issue 11 2009MingXi Tang The soybean-derived serine protease inhibitor, Bowman,Birk inhibitor (BBI), has been reported as a potent chemoprevention agent against several types of tumors. The present study was undertaken to evaluate the effects of BBI on androgen-sensitive/dependent prostate cancers using a human prostate cancer cell (LNCaP) and the transgenic rats developing adenocarcinoma of the prostate (TRAP) model. Treatment of LNCaP prostate cancer cells with 500 µg/mL BBI resulted in inhibition of viability measured on WST-1 assays, with induction of connexin 43 (C×43) and cleaved caspase-3 protein expression. Feeding of 3% roughly prepared BBI (BBIC) to TRAP from the age 3 weeks to 13 weeks resulted in significant reduction of the relative epithelial areas within the acinus and multiplicity of the adenocarcinomas in the lateral prostate lobes. C×43- and terminal deoxynucleotidyl transferase mediated dUTP-biotin end labeling of fragmented DNA (TUNEL)-positive apoptotic cancer cells were more frequently observed in the lateral prostates treated with BBIC than in the controls. These in vivo and in vitro results suggest that BBI possesses chemopreventive activity associated with induction of C×43 expression and apoptosis. [source] Upper susceptibility threshold limits with confidence intervals: a method to identify normal and abnormal population values for laboratory toxicological parameters, based on acetylcholinesterase activities in sea licePEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 3 2006Anders Fallang Abstract The interpretation and importance of comparing field values of susceptibility to pesticides with a laboratory reference strain that might bear little resemblance to the actual situation in the field are problematic and a continuing subject of debate. In this paper a procedure for defining a ,normal sensitive' population from a field study of 383 individuals to provide a basis for analysing and interpreting in vitro results is described and examined. Instead of using only the 95th percentile, the upper and lower confidence limits for the 95th percentile were also compared to select the best estimation of the limit for the normal material. A field population constrained by the upper confidence limit for the 95th percentile provides appropriate descriptions of the normal material in this study. This approach should prove useful in studies of pesticide resistance in field populations. Copyright © 2006 Society of Chemical Industry [source] WST11, A Novel Water-soluble Bacteriochlorophyll Derivative; Cellular Uptake, Pharmacokinetics, Biodistribution and Vascular-targeted Photodynamic Activity Using Melanoma Tumors as a Model,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2005Ohad Mazor ABSTRACT WST11 is a novel negatively charged water-soluble palladiumbacteriochlorophyll derivative that was developed for vascular-targeted photodynamic therapy (VTP) in our laboratory. The in vitro results suggest that WST11 cellular uptake, clearance and phototoxicity are mediated by serum albumin trafficking. In vivo, WST11 was found to clear rapidly from the circulation (t1/2= 1.65 min) after intravenous bolus injection in the mouse, whereas a longer clearance time (t1/2= 7.5 min) was noted in rats after 20 min of infusion. The biodistribution of WST11 in mouse tissues indicates hepatic clearance (t1/2= 20 min), with minor (kidney, lung and spleen) or no intermediary accumulation in other tissues. As soon as 1 h after injection, WST11 had nearly cleared from the body of the mouse, except for a temporal accumulation in the lungs from which it cleared within 40 min. On the basis of these results, we set the VTP protocol for a short illumination period (5 min), delivered immediately after WST11 injection. On subjecting M2R melanoma xenografts to WST11-VTP, we achieved 100% tumor flattening at all doses and a 70% cure with 9 mg/kg and a light exposure dose of 100 mW/cm2. These results provide direct evidence that WST11 is an effective agent for VTP and provide guidelines for further development of new candidates. [source] In Vitro Phototoxic Properties of Triamcinolone 16,17-acetonide and Its Main Photoproducts,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 5 2003Giorgia Miolo ABSTRACT The phototoxicity of triamcinolone 16,17-acetonide has been estimated through a panel of,in vitro tests. The main target involved in phototoxicity induced by triamcinolone appeared to be the cell membrane. Oxygen-independent photohemolysis was observed. A photochemical study in water and buffered solutions supported the conclusion that this is related to the action of radicals formed upon UV irradiation (in particular UV-B) by Norrish Type-I fragmentation of the C-20 ketone group. Peroxy radicals were formed in the presence of oxygen and were the active species in that case. Three photoproducts, isolated from the photodegradation of the drug, were submitted to the same toxicity tests. Two of them were proved to possess toxic or phototoxic properties on erythrocytes, primarily induced by UV-B light, and may participate in the photosensitizing activity of triamcinolone 16,17-acetonide. Our in vitro results suggest that the drug can elicit weak photosensitizing properties in vivo. [source] Antispasmodic activity of extracts and compounds of Acalypha phleoides Cav.,PHYTOTHERAPY RESEARCH, Issue 2 2004Adela Astudillo Abstract The aerial parts of Acalypha phleoides are usually prescribed in the Mexican traditional medicine for a variety of gastrointestinal complaints. The MeOH,CHCl3 (1:1) extract of the aerial part of A. phleoides showed an inhibitory effect on the gastrointestinal propulsion of a charcoal meal in mice. In isolated guinea-pig ileum, this extract produced a concentration dependent inhibition of the contractions induced by 5-hydroxytryptamine, but it was unable to inhibit the contractions elicited by acetylcholine, histamine, KCl and BaCl2. This extract produced also a concentration dependent inhibition of the spontaneous pendular movement of the isolated rabbit jejunum. This inhibitory activity was partially blocked by propranolol. The essential oil, obtained from the aerial part of this plant, was more potent than the MeOH,CHCl3 (1:1) extract in inhibiting the spontan-eous pendular movement of the rabbit jejunum. Thymol, camphor and , -terpinene were identi,ed from the essential oil by GC-MS. These monoterpenes showed antispasmodic activity in the rabbit jejunum preparation, thymol was the most active compound, followed by camphor and , -terpinene. Thymol and camphor in high concentrations also showed tracheal relaxant properties, but , -terpinene did not. These in vivo and in vitro results tend to support the traditional use of A. phleoides as an antispasmodic agent. Copyright © 2004 John Wiley & Sons, Ltd. [source] Cryotolerance of Bovine Blastocysts is Affected by Oocyte Maturation in Media Containing Palmitic or Stearic AcidREPRODUCTION IN DOMESTIC ANIMALS, Issue 1 2009MA Shehab-El-Deen Contents In this study, non-esterified fatty acids (NEFAs) were added during in vitro maturation at concentrations measured previously in follicular fluid (FF) of high-producing dairy cows in a negative energy status to evaluate their subsequent effect on the embryos cryotolerance. Oocytes were matured for 24 h in serum-free media with or without (negative control) the addition of NEFAs dissolved in ethanol or ethanol alone (positive control). Matured oocytes were fertilized and cultured for 7 days in synthetic oviduct fluid medium supplemented with 5% FCS. Embryos that had at least reached the blastocyst stage were vitrified by open pulled straw (OPS) vitrification. Addition of palmitic (C16 : 0) or stearic acid (C18 : 0) during oocyte maturation had significant negative effects on embryo cryotolerance, whereas ethanol or oleic acid (C18 : 1) had no effect. These in vitro results suggest that high NEFA concentrations in FF during a period of negative energy balance in high-yielding dairy cows can have carry-over effects on embryo quality. [source] Nuclear-targeted minicircle to enhance gene transfer with non-viral vectors in vitro and in vivoTHE JOURNAL OF GENE MEDICINE, Issue 6 2006Laurence Vaysse Abstract Background To develop more efficient non-viral vectors, we have previously described a novel approach to attach a nuclear localisation signal (NLS) to plasmid DNA, by generating a fusion protein between the tetracycline repressor protein TetR and an SV40 NLS peptide (TetR-NLS). The high affinity of TetR for the DNA sequence tetO is used to bind the NLS to DNA. We have now investigated the ability of this system displaying the SV40 NLS or HIV-1 TAT peptide to enhance nuclear import of a minimised DNA construct more suitable for in vivo gene delivery: a minicircle. Methods We have produced a new LacZ minicircle compatible with the TetR system. After transfection of the minicircle in combination with TetR-NLS or TetR-TAT using different transfection agents, we first measured ,-galactosidase activity in vitro. We then used a special delivery technique, in which DOTAP/cholesterol liposomes and DNA/protein complexes are sequentially injected intravenously, to evaluate the activity of this system in vivo. Results In vitro results showed a 30-fold increase in transfection efficiency of the nuclear-targeted minicircle compared to normal plasmid lipofection. Results on cell cycle arrested cells seem to indicate a different mechanism between the TetR-NLS and TetR-TAT. Finally, we demonstrate a more than 6-fold increase in ,-galactosidase expression in the mouse lung using the minicircle and the TetR-TAT protein. This increase is specific for the peptide sequence and is not observed with the control protein TetR. Conclusions Our results indicate that the combination of a minicircle DNA construct with a TetR nuclear-targeting system is able to potentiate gene expression of non-viral vectors. Copyright © 2006 John Wiley & Sons, Ltd. [source] Influence of topical antifungal drugs on ciliary beat frequency of human nasal mucosa,THE LARYNGOSCOPE, Issue 7 2010An In Vitro Study Abstract Objectives/Hypothesis: Topical antifungal treatment is a subject of discussion in the treatment of chronic rhinosinusitis. The aim of this research was to study the effects of antifungal drugs on ciliary beat frequency (CBF) of human nasal mucosa under in vitro conditions. Study Design: Case series of in vitro experiments and in vitro study of cultured ciliated cells of human nasal mucosa. Methods: Human nasal mucosa was acquired during routine endoscopic sinus surgery. Cells were cultivated on object slides and exposed to different antifungal drugs in a newly developed test system. This system allowed continuous and reproducible exposure to different drugs at constant temperature, pH value, and osmolarity. The drugs were amphotericin B in two different concentrations and itraconazole. Results: Rinsing with higher concentrations of amphotericin B led to an immediate decrease of CBF, with a total stop after 15 minutes. A different result was seen in the group with lower concentrations; CBF decreased again quickly after rinsing with the test drug, but all of them recovered after rinsing with neutral solution. When using itraconazole a decline in CBF was observed again; one half of the samples returned to activity. Conclusions: Our in vitro results demonstrate a dose-dependent effect of the antifungal drugs amphotericin B and itraconazole on ciliary beat frequency of human nose epithelium. Laryngoscope, 2010 [source] Numerical Simulation of Thrombus Aspiration in Two Realistic Models of Catheter TipsARTIFICIAL ORGANS, Issue 4 2010Giancarlo Pennati Abstract Thrombus aspiration catheters are devices used to remove a blood clot from a vessel, usually prior to angioplasty or stent implantation. However, in vitro results showed that the use of different commercial devices could produce very different thrombus removals, suggesting a primary dependence on the distal tip configuration of the catheter. A computational methodology based on realistic catheter tip modeling was developed to investigate the factors affecting the thrombus suction. Two different designs were considered, either with a single central lumen or a combination of central and side holes. First, steady-state aspiration of distilled water from a reservoir was simulated and compared with experimental tests. Subsequently, the aspiration of a totally occlusive thrombus, modeled as a high viscous fluid, was simulated solving a complex two-phase (blood and thrombus) problem. In particular, the benefit of additional openings was investigated. Good matching between the steady-state experimental and numerically simulated hydraulic behaviors allowed a validation of the numerical models. Numerical results of thrombus aspiration showed that the catheter with central and side holes had a worse performance if compared with the single central lumen catheter. Indeed, the inlets in contact with both blood and thrombus preferentially aspirate blood due to its much lower viscosity. This effect hindered the aspiration of thrombus. The amount of aspirated thrombus highly depends on the complex, two-phase fluid dynamics occurring across the catheter tips. Results suggested that location of additional holes is crucial in the catheter aspiration performance. [source] Functional and Biocompatibility Performances of an Integrated Maglev Pump-OxygenatorARTIFICIAL ORGANS, Issue 1 2009Tao Zhang Abstract To provide respiratory support for patients with lung failure, a novel compact integrated pump-oxygenator is being developed. The functional and biocompatibility performances of this device are presented. The pump-oxygenator is designed by combining a magnetically levitated pump/rotor with a uniquely configured hollow fiber membrane bundle to create an assembly free, ultracompact, all-in-one system. The hemodynamics, gas transfer and biocompatibility performances of this novel device were investigated both in vitro in a circulatory flow loop and in vivo in an ovine animal model. The in vitro results showed that the device was able to pump blood flow from 2 to 8 L/min against a wide range of pressures and to deliver an oxygen transfer rate more than 300 mL/min at a blood flow of 6 L/min. Blood damage tests demonstrated low hemolysis (normalized index of hemolysis [NIH],0.04) at a flow rate of 5 L/min against a 100-mm Hg afterload. The data from five animal experiments (4 h to 7 days) demonstrated that the device could bring the venous blood to near fully oxygen-saturated condition (98.6% ± 1.3%). The highest oxygen transfer rate reached 386 mL/min. The gas transfer performance was stable over the study duration for three 7-day animals. There was no indication of blood damage. The plasma free hemoglobin and platelet count were within the normal ranges. No gross thrombus is found on the explanted pump components and fiber surfaces. Both in vitro and in vivo results demonstrated that the newly developed pump-oxygenator can achieve sufficient blood flow and oxygen transfer with excellent biocompatibility. [source] Species differences in enantioselective 2-oxidations of RS-8359, a selective and reversible MAO-A inhibitor, and cinchona alkaloids by aldehyde oxidaseBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 3 2006Kunio Itoh Abstract The 2-oxidation activity on the pyrimidine ring of RS-8359, a MAO-A inhibitor, is the major metabolic pathway catalysed by aldehyde oxidase. This study investigated the species differences in the 2-oxidation activity by using liver cytosolic fractions from rats, mice, guinea-pigs, rabbits, dogs, monkeys and humans. The Vmax/Km value for the (S)-enantiomer of RS-8359 was extremely high in monkeys and humans, moderate in guinea-pigs, and low in rats and mice. Dogs were deficient in 2-oxidation activity. The (R)-enantiomer was only oxidized at a very low rate in guinea-pigs, monkeys and humans, and not oxidized in rats, mice and rabbits. Thus, marked species differences and enantioselectivity were obvious for the 2-oxidation of the (S)-enantiomer of RS-8359. The in vitro results were in good accordance with previously reported in vivo excretion data of the 2-keto metabolite and the non-detectable plasma concentrations of the (S)-enantiomer in monkeys and humans after administration of racemic RS-8359. Enantioselectivity was also observed for the oxidation of cinchona alkaloids catalysed by aldehyde oxidase. Among the four cinchona alkaloids studied, the oxidation activity of cinchonidine, which has no substituents at the 6-hydroxy group but bears (8S,9R)-configurations, was highest. As opposed to the (S)-enantiomer, an extremely high catalytic activity of cinchonidine was confirmed in rabbits, but not in monkeys or humans. Rabbit liver aldehyde oxidase was suggested to have characteristic properties around the active site. Copyright © 2006 John Wiley & Sons, Ltd. [source] A model to quantify encrustation on ureteric stents, urethral catheters and polymers intended for urological useBJU INTERNATIONAL, Issue 4 2000S.K.S. Choong Objective To validate an encrustation model and to quantify encrustation on currently used urological devices and polymers intended for urological use. Materials and methods An encrustation model was validated: (i) to measure the amount of calcium leaching from the glass model and from the polymer used; (ii) to determine whether the use of a single-source or pooled urine produced similar results; (iii) to determine in vitro encrustation; and (iv) to compare the results of in vivo implantation of the same materials into the bladders of rodents with the in vitro results. A test polymer (a ureteric stent, a urethral catheter or a biomaterial) and a control silicone polymer were housed separately but received human urine from the same reservoir and under the same conditions (pH 6.0 and 37 °C) for 5 days. The amount of calcium encrustation on each polymer was measured using atomic absorption spectroscopy. Each experiment was repeated at least four times and the results expressed as an encrustation index, defined as the ratio of encrustation of the test and reference polymers. Results The amount of calcium leaching from the glass model and polymers tested was insignificant. The use of a single-source or pooled urine gave the same results in the encrustation model. The in vitro results correlated with in vivo implantation of disks into the bladders of rats. Among the commonly used ureteric stents tested, the Cook C-Flex ureteric stents encrusted least. Hydrogel-coated ureteric stents encrusted more than uncoated stents. The Bard polytetrafluoroethylene short-term urethral catheter encrusted more than the Bard hydrogel-coated long-term catheter. A plasma-activated surface modification of a synthetic biomaterial with hyaluronic acid encrusted less than silicone, a long-term biomaterial widely regarded as the ,gold standard'. Conclusion This validated encrustation model is the first to quantify encrustation on currently available ureteric stents and urethral catheters. A novel coating for a biomaterial was identified using the encrustation model, and which encrusted less than silicone. [source] Expression of HNFs and C/EBP, is correlated with immunocytochemical differentiation of cell lines derived from human hepatocellular carcinomas, hepatoblastomas and immortalized hepatocytesCANCER SCIENCE, Issue 9 2003Tadashi Ishiyama Objective assessment of the differentiation grade of hepatocellular carcinomas (HCCs) is important for evaluation of the pathological diagnosis, prognosis and therapeutic treatment. Differentiation of hepatocytes is reflected by their expression of hepatic functional proteins in the mouse embryo, and liver-enriched transcription factors (LETFs) have been shown to regulate hepatic functional genes strictly. Previous reports demonstrated that the level of LETF expression is altered in HCC or preneoplastic nodules compared with noncancerous tissues. Therefore, LETF expression levels might be useful as a measure of HCC maturation. In this study, to clarify the correlation between the expression of LETFs and the differentiation grade of HCCs, we performed a quantitative analysis of the mRNA expressions of HNFs and C/EBP, using real-time reverse-transcription PCR and immunocytochemical analysis for hepatic functional proteins in twelve cell lines. Furthermore, we examined orthotopic transplantations of the HCC cell lines in C.B-17/Icrj-scid/scid mice and characterized the histologic and cytologic differentiation of the tumors that developed. Our results showed that comprehensive expressions of HNF-3,, HNF-4,, HNF-1,, and C/EBP, were specific to HCCs with well-differentiated function and morphology. Furthermore, among these four transcription factors, HNF-4, and HNF-1, expressions showed synchronism and had a close relation with HCC differentiation. These in vitro results were confirmed in tumors developed in SCID mice in vivo. These findings suggested that HNF-4, and HNF-1, are useful markers to assess the degree of HCC differentiation, which we suggest could be evaluated objectively by the quantitative analysis of HNFs and C/EBP, in HCCs. [source] | ||||||||||||||||